TY - JOUR A1 - Ungelenk, Johannes T1 - Émile Zola and the literary language of climate change JF - Nottingham French studies / University of Nottingham N2 - On 7 February 1861, John Tyndall, professor of natural philosophy, delivered a historical lecture: he could prove that different gases absorb heat to a very different degree, which implies that the temperate conditions provided for by the Earth's atmosphere are dependent on its particular composition of gases. The theoretical foundation of climate science was laid. Ten years later, on the other side of the Channel, a young and ambitious author was working on a comprehensive literary analysis of the French era under the Second Empire. Émile Zola had probably not heard or read of Tyndall's discovery. However, the article makes the case for reading Zola's Rougon-Macquart as an extensive story of climate change. Zola's literary attempts to capture the defining characteristic of the Second Empire led him to the insight that its various milieus were all part of the same ‘climate’: that of an all-encompassing warming. Zola suggests that this climate is man-made: the economic success of the Second Empire is based on heating, in a literal and metaphorical sense, as well as on stoking the steam-engines and creating the hypertrophic atmosphere of the hothouse that enhances life and maximises turnover and profit. In contrast to Tyndall and his audience, Zola sensed the catastrophic consequences of this warming: the Second Empire was inevitably moving towards a final débâcle, i.e. it was doomed to perish in local and ‘global’ climate catastrophes. The article foregrounds the supplementary status of Tyndall's physical and Zola's literary knowledge. As Zola's striking intuition demonstrates, literature appears to have a privileged approach to the phenomenon of man-induced climate change. N2 - Le 7 février 1861, le professeur de philosophie naturelle John Tyndall donna une communication historique: il pouvait prouver que des gaz différents absorbent la chaleur de manière différente, ce qui implique que les conditions tempérées fournies par l’atmosphère terrestre dépendent de sa composition particulière en gaz. Le fondement théorique de la science climatique était posé. Dix ans plus tard, de l'autre côté du Channel, un jeune auteur ambitieux était en train de faire une analyse littéraire globale de la France du Second Empire. Émile Zola n'avait probablement pas entendu parler de la découverte de Tyndall. Cependant, cet article propose de lire les Rougon Macquart de Zola comme une vaste histoire du changement climatique. Les tentatives littéraires entreprises par Zola pour capturer la caractéristique déterminante du Second Empire l'amena à réaliser que ses différents milieux faisaient tous partie du même « climat »: celui d'un réchauffement global. Zola suggère que ce climat est créé par l'humain et que le succès économique du Second Empire est basé sur l'action de chauffer dans un sens littéral et métaphorique, ainsi que sur l'alimentation des machines à vapeur et la création de l'atmosphère hypertrophiée d'une serre qui enrichit la vie et maximise l'écoulement et le profit. Contrairement à Tyndall et à son auditoire, Zola pressentit les conséquences catastrophiques d'un tel réchauffement: le Second Empire s'approchait inévitablement d'une débâcle finale, c'est-à-dire qu'il était voué à périr dans des catastrophes locales et « globales ». KW - Rougon-Macquart KW - climate change KW - John Tyndall KW - global warming KW - climate catastrophe KW - Second Empire KW - changement climatique KW - réchauffement planétaire KW - catastrophe climatique KW - Rougon-Macquart KW - Second Empire KW - John Tyndall Y1 - 2021 U6 - https://doi.org/10.3366/nfs.2021.0331 SN - 0029-4586 SN - 2047-7236 VL - 60 IS - 3 SP - 362 EP - 373 PB - Edinburgh University Press CY - Edinburgh ER - TY - JOUR A1 - Ungelenk, Johannes T1 - Émile Zola and the Literary Language of Climate Change JF - Nottingham French Studies N2 - On 7 February 1861, John Tyndall, professor of natural philosophy, delivered a historical lecture: he could prove that different gases absorb heat to a very different degree, which implies that the temperate conditions provided for by the Earth's atmosphere are dependent on its particular composition of gases. The theoretical foundation of climate science was laid. Ten years later, on the other side of the Channel, a young and ambitious author was working on a comprehensive literary analysis of the French era under the Second Empire. Émile Zola had probably not heard or read of Tyndall's discovery. However, the article makes the case for reading Zola's Rougon-Macquart as an extensive story of climate change. Zola's literary attempts to capture the defining characteristic of the Second Empire led him to the insight that its various milieus were all part of the same ‘climate’: that of an all-encompassing warming. Zola suggests that this climate is man-made: the economic success of the Second Empire is based on heating, in a literal and metaphorical sense, as well as on stoking the steam-engines and creating the hypertrophic atmosphere of the hothouse that enhances life and maximises turnover and profit. In contrast to Tyndall and his audience, Zola sensed the catastrophic consequences of this warming: the Second Empire was inevitably moving towards a final débâcle, i.e. it was doomed to perish in local and ‘global’ climate catastrophes. The article foregrounds the supplementary status of Tyndall's physical and Zola's literary knowledge. As Zola's striking intuition demonstrates, literature appears to have a privileged approach to the phenomenon of man-induced climate change. N2 - Le 7 février 1861, le professeur de philosophie naturelle John Tyndall donna une communication historique: il pouvait prouver que des gaz différents absorbent la chaleur de manière différente, ce qui implique que les conditions tempérées fournies par l’atmosphère terrestre dépendent de sa composition particulière en gaz. Le fondement théorique de la science climatique était posé. Dix ans plus tard, de l'autre côté du Channel, un jeune auteur ambitieux était en train de faire une analyse littéraire globale de la France du Second Empire. Émile Zola n'avait probablement pas entendu parler de la découverte de Tyndall. Cependant, cet article propose de lire les Rougon Macquart de Zola comme une vaste histoire du changement climatique. Les tentatives littéraires entreprises par Zola pour capturer la caractéristique déterminante du Second Empire l'amena à réaliser que ses différents milieux faisaient tous partie du même « climat »: celui d'un réchauffement global. Zola suggère que ce climat est créé par l'humain et que le succès économique du Second Empire est basé sur l'action de chauffer dans un sens littéral et métaphorique, ainsi que sur l'alimentation des machines à vapeur et la création de l'atmosphère hypertrophiée d'une serre qui enrichit la vie et maximise l'écoulement et le profit. Contrairement à Tyndall et à son auditoire, Zola pressentit les conséquences catastrophiques d'un tel réchauffement: le Second Empire s'approchait inévitablement d'une débâcle finale, c'est-à-dire qu'il était voué à périr dans des catastrophes locales et « globales ». KW - Rougon-Macquart KW - climate change KW - John Tyndall KW - global warming KW - climate catastrophe KW - Second Empire KW - changement climatique KW - réchauffement planétaire KW - catastrophe climatique KW - Second Empire Y1 - 2021 U6 - https://doi.org/https://doi.org/10.3366/nfs.2021.0331 VL - 60 IS - 3 SP - 362 EP - 373 ER - TY - JOUR A1 - Korup, Oliver A1 - Görüm, Tolga A1 - Hayakawa, Yuichi T1 - Without power? - Landslide inventories in the face of climate change JF - Earth surface processes and landforms : the journal of the British Geomorphological Research Group N2 - Projected scenarios of climate change involve general predictions about the likely changes to the magnitude and frequency of landslides, particularly as a consequence of altered precipitation and temperature regimes. Whether such landslide response to contemporary or past climate change may be captured in differing scaling statistics of landslide size distributions and the erosion rates derived thereof remains debated. We test this notion with simple Monte Carlo and bootstrap simulations of statistical models commonly used to characterize empirical landslide size distributions. Our results show that significant changes to total volumes contained in such inventories may be masked by statistically indistinguishable scaling parameters, critically depending on, among others, the size of the largest of landslides recorded. Conversely, comparable model parameter values may obscure significant, i.e. more than twofold, changes to landslide occurrence, and thus inferred rates of hillslope denudation and sediment delivery to drainage networks. A time series of some of Earth's largest mass movements reveals clustering near and partly before the last glacial-interglacial transition and a distinct step-over from white noise to temporal clustering around this period. However, elucidating whether this is a distinct signal of first-order climate-change impact on slope stability or simply coincides with a transition from short-term statistical noise to long-term steady-state conditions remains an important research challenge. KW - landslide KW - climate change KW - magnitude & frequency Y1 - 2012 U6 - https://doi.org/10.1002/esp.2248 SN - 0197-9337 VL - 37 IS - 1 SP - 92 EP - 99 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Šedová, Barbora A1 - Kalkuhl, Matthias T1 - Who are the climate migrants and where do they go? BT - Evidence from rural India JF - World development N2 - In this paper, we move from the large strand of research that looks at evidence of climate migration to the questions: who are the climate migrants? and where do they go? These questions are crucial to design policies that mitigate welfare losses of migration choices due to climate change. We study the direct and heterogeneous associations between weather extremes and migration in rural India. We combine ERAS reanalysis data with the India Human Development Survey household panel and conduct regression analyses by applying linear probability and multinomial logit models. This enables us to establish a causal relationship between temperature and precipitation anomalies and overall migration as well as migration by destination. We show that adverse weather shocks decrease rural-rural and international migration and push people into cities in different, presumably more prosperous states. A series of positive weather shocks, however, facilitates international migration and migration to cities within the same state. Further, our results indicate that in contrast to other migrants, climate migrants are likely to be from the lower end of the skill distribution and from households strongly dependent on agricultural production. We estimate that approximately 8% of all rural-urban moves between 2005 and 2012 can be attributed to weather. This figure might increase as a consequence of climate change. Thus, a key policy recommendation is to take steps to facilitate integration of less educated migrants into the urban labor market. KW - climate change KW - migration KW - household analysis KW - India KW - econometrics Y1 - 2020 U6 - https://doi.org/10.1016/j.worlddev.2019.104848 SN - 0305-750X SN - 1873-5991 VL - 129 PB - Elsevier Science CY - Amsterdam ER - TY - JOUR A1 - Markovic, Danijela A1 - Carrizo, Savrina F. A1 - Kaercher, Oskar A1 - Walz, Ariane A1 - David, Jonathan N. W. T1 - Vulnerability of European freshwater catchments to climate change JF - Global change biology N2 - Climate change is expected to exacerbate the current threats to freshwater ecosystems, yet multifaceted studies on the potential impacts of climate change on freshwater biodiversity at scales that inform management planning are lacking. The aim of this study was to fill this void through the development of a novel framework for assessing climate change vulnerability tailored to freshwater ecosystems. The three dimensions of climate change vulnerability are as follows: (i) exposure to climate change, (ii) sensitivity to altered environmental conditions and (iii) resilience potential. Our vulnerability framework includes 1685 freshwater species of plants, fishes, molluscs, odonates, amphibians, crayfish and turtles alongside key features within and between catchments, such as topography and connectivity. Several methodologies were used to combine these dimensions across a variety of future climate change models and scenarios. The resulting indices were overlaid to assess the vulnerability of European freshwater ecosystems at the catchment scale (18 783 catchments). The Balkan Lakes Ohrid and Prespa and Mediterranean islands emerge as most vulnerable to climate change. For the 2030s, we showed a consensus among the applied methods whereby up to 573 lake and river catchments are highly vulnerable to climate change. The anthropogenic disruption of hydrological habitat connectivity by dams is the major factor reducing climate change resilience. A gap analysis demonstrated that the current European protected area network covers <25% of the most vulnerable catchments. Practical steps need to be taken to ensure the persistence of freshwater biodiversity under climate change. Priority should be placed on enhancing stakeholder cooperation at the major basin scale towards preventing further degradation of freshwater ecosystems and maintaining connectivity among catchments. The catchments identified as most vulnerable to climate change provide preliminary targets for development of climate change conservation management and mitigation strategies. KW - catchment connectivity KW - climate change KW - exposure KW - freshwater biodiversity KW - gap analysis KW - resilience KW - sensitivity KW - vulnerability Y1 - 2017 U6 - https://doi.org/10.1111/gcb.13657 SN - 1354-1013 SN - 1365-2486 VL - 23 SP - 3567 EP - 3580 PB - Wiley CY - Hoboken ER - TY - GEN A1 - Pearce, Warren A1 - Özkula, Suay M. A1 - Greene, Amanda K. A1 - Teeling, Lauren A1 - Bansard, Jennifer S. A1 - Omena, Janna Joceli A1 - Rabello, Elaine Teixeira T1 - Visual cross-platform analysis BT - Digital methods to research social media images T2 - Zweitveröffentlichungen der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe N2 - Analysis of social media using digital methods is a flourishing approach. However, the relatively easy availability of data collected via platform application programming interfaces has arguably led to the predominance of single-platform research of social media. Such research has also privileged the role of text in social media analysis, as a form of data that is more readily gathered and searchable than images. In this paper, we challenge both of these prevailing forms of social media research by outlining a methodology for visual cross-platform analysis (VCPA), defined as the study of still and moving images across two or more social media platforms. Our argument contains three steps. First, we argue that cross-platform analysis addresses a gap in research methods in that it acknowledges the interplay between a social phenomenon under investigation and the medium within which it is being researched, thus illuminating the different affordances and cultures of web platforms. Second, we build on the literature on multimodal communication and platform vernacular to provide a rationale for incorporating the visual into cross-platform analysis. Third, we reflect on an experimental cross-platform analysis of images within social media posts (n = 471,033) used to communicate climate change to advance different modes of macro- and meso-levels of analysis that are natively visual: image-text networks, image plots and composite images. We conclude by assessing the research pathways opened up by VCPA, delineating potential contributions to empirical research and theory and the potential impact on practitioners of social media communication. T3 - Zweitveröffentlichungen der Universität Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe - 199 KW - research methodology KW - visual analysis KW - social media KW - climate change Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-515539 SN - 1867-5808 IS - 2 ER - TY - JOUR A1 - Pearce, Warren A1 - Özkula, Suay M. A1 - Greene, Amanda K. A1 - Teeling, Lauren A1 - Bansard, Jennifer S. A1 - Omena, Janna Joceli A1 - Rabello, Elaine Teixeira T1 - Visual cross-platform analysis JF - Information, Communication and Society: digital methods to research social media images N2 - Analysis of social media using digital methods is a flourishing approach. However, the relatively easy availability of data collected via platform application programming interfaces has arguably led to the predominance of single-platform research of social media. Such research has also privileged the role of text in social media analysis, as a form of data that is more readily gathered and searchable than images. In this paper, we challenge both of these prevailing forms of social media research by outlining a methodology for visual cross-platform analysis (VCPA), defined as the study of still and moving images across two or more social media platforms. Our argument contains three steps. First, we argue that cross-platform analysis addresses a gap in research methods in that it acknowledges the interplay between a social phenomenon under investigation and the medium within which it is being researched, thus illuminating the different affordances and cultures of web platforms. Second, we build on the literature on multimodal communication and platform vernacular to provide a rationale for incorporating the visual into cross-platform analysis. Third, we reflect on an experimental cross-platform analysis of images within social media posts (n = 471,033) used to communicate climate change to advance different modes of macro- and meso-levels of analysis that are natively visual: image-text networks, image plots and composite images. We conclude by assessing the research pathways opened up by VCPA, delineating potential contributions to empirical research and theory and the potential impact on practitioners of social media communication. KW - research methodology KW - visual analysis KW - social media KW - climate change Y1 - 2018 U6 - https://doi.org/10.1080/1369118X.2018.1486871 SN - 1468-4462 SN - 1369-118X VL - 23 IS - 2 SP - 161 EP - 180 PB - Routledge CY - London ER - TY - JOUR A1 - Tabares Jimenez, Ximena del Carmen A1 - Zimmermann, Heike Hildegard A1 - Dietze, Elisabeth A1 - Ratzmann, Gregor A1 - Belz, Lukas A1 - Vieth-Hillebrand, Andrea A1 - Dupont, Lydie A1 - Wilkes, Heinz A1 - Mapani, Benjamin A1 - Herzschuh, Ulrike T1 - Vegetation state changes in the course of shrub encroachment in an African savanna since about 1850 CE and their potential drivers JF - Ecology and evolution N2 - Shrub encroachment has far-reaching ecological and economic consequences in many ecosystems worldwide. Yet, compositional changes associated with shrub encroachment are often overlooked despite having important effects on ecosystem functioning. We document the compositional change and potential drivers for a northern Namibian Combretum woodland transitioning into a Terminalia shrubland. We use a multiproxy record (pollen, sedimentary ancient DNA, biomarkers, compound-specific carbon (delta C-13) and deuterium (delta D) isotopes, bulk carbon isotopes (delta(13)Corg), grain size, geochemical properties) from Lake Otjikoto at high taxonomical and temporal resolution. We provide evidence that state changes in semiarid environments may occur on a scale of one century and that transitions between stable states can span around 80 years and are characterized by a unique vegetation composition. We demonstrate that the current grass/woody ratio is exceptional for the last 170 years, as supported by n-alkane distributions and the delta C-13 and delta(13)Corg records. Comparing vegetation records to environmental proxy data and census data, we infer a complex network of global and local drivers of vegetation change. While our delta D record suggests physiological adaptations of woody species to higher atmospheric pCO(2) concentration and drought, our vegetation records reflect the impact of broad-scale logging for the mining industry, and the macrocharcoal record suggests a decrease in fire activity associated with the intensification of farming. Impact of selective grazing is reflected by changes in abundance and taxonomical composition of grasses and by an increase of nonpalatable and trampling-resistant taxa. In addition, grain-size and spore records suggest changes in the erodibility of soils because of reduced grass cover. Synthesis. We conclude that transitions to an encroached savanna state are supported by gradual environmental changes induced by management strategies, which affected the resilience of savanna ecosystems. In addition, feedback mechanisms that reflect the interplay between management legacies and climate change maintain the encroached state. KW - climate change KW - fossil pollen KW - land-use change KW - savanna ecology KW - sedimentary ancient DNA KW - state and transition KW - tree-grass interactions Y1 - 2019 U6 - https://doi.org/10.1002/ece3.5955 SN - 2045-7758 VL - 10 IS - 2 SP - 962 EP - 979 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Wolf, Sabina A1 - Pham, My A1 - Matthews, Nathanial A1 - Bubeck, Philip T1 - Understanding the implementation gap BT - policy-makers’ perceptions of ecosystem-based adaptation in Central Vietnam JF - Climate & development N2 - In recent years, nature-based solutions are receiving increasing attention in the field of disaster risk reduction and climate change adaptation as inclusive, no regret approaches. Ecosystem-based adaptation (EbA) can mitigate the impacts of climate change, build resilience and tackle environmental degradation thereby supporting the targets set by the 2030 Agenda, the Paris Agreement and the Sendai Framework. Despite these benefits, EbA is still rarely implemented in practice. To better understand the barriers to implementation, this research examines policy-makers' perceptions of EbA, using an extended version of Protection Motivation Theory as an analytical framework. Through semi-structured interviews with policy-makers at regional and provincial level in Central Vietnam, it was found that EbA is generally considered a promising response option, mainly due to its multiple ecosystem-service benefits. The demand for EbA measures was largely driven by the perceived consequences of natural hazards and climate change. Insufficient perceived response efficacy and time-lags in effectiveness for disaster risk reduction were identified as key impediments for implementation. Pilot projects and capacity building on EbA are important means to overcome these perceptual barriers. This paper contributes to bridging the knowledge-gap on political decision-making regarding EbA and can, thereby, promote its mainstreaming into policy plans. KW - climate change KW - ecosystem-based adaptation KW - risk perception KW - protection KW - motivation theory KW - decision making Y1 - 2020 U6 - https://doi.org/10.1080/17565529.2020.1724068 SN - 1756-5529 SN - 1756-5537 VL - 13 IS - 1 SP - 81 EP - 94 PB - Taylor & Francis LTD CY - Abingdon ER - TY - JOUR A1 - Tape, Ken D. A1 - Jones, Benjamin M. A1 - Arp, Christopher D. A1 - Nitze, Ingmar A1 - Grosse, Guido T1 - Tundra be dammed BT - beaver colonization of the arctic JF - Global change biology N2 - Increasing air temperatures are changing the arctic tundra biome. Permafrost is thawing, snow duration is decreasing, shrub vegetation is proliferating, and boreal wildlife is encroaching. Here we present evidence of the recent range expansion of North American beaver (Castor canadensis) into the Arctic, and consider how this ecosystem engineer might reshape the landscape, biodiversity, and ecosystem processes. We developed a remote sensing approach that maps formation and disappearance of ponds associated with beaver activity. Since 1999, 56 new beaver pond complexes were identified, indicating that beavers are colonizing a predominantly tundra region (18,293km(2)) of northwest Alaska. It is unclear how improved tundra stream habitat, population rebound following overtrapping for furs, or other factors are contributing to beaver range expansion. We discuss rates and likely routes of tundra beaver colonization, as well as effects on permafrost, stream ice regimes, and freshwater and riparian habitat. Beaver ponds and associated hydrologic changes are thawing permafrost. Pond formation increases winter water temperatures in the pond and downstream, likely creating new and more varied aquatic habitat, but specific biological implications are unknown. Beavers create dynamic wetlands and are agents of disturbance that may enhance ecosystem responses to warming in the Arctic. KW - arctic tundra KW - beaver KW - climate change KW - permafrost KW - population recovery KW - salmon KW - shrub expansion KW - stream Y1 - 2018 U6 - https://doi.org/10.1111/gcb.14332 SN - 1354-1013 SN - 1365-2486 VL - 24 IS - 10 SP - 4478 EP - 4488 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Steffen, Will A1 - Röckstrom, Johan A1 - Richardson, Katherine A1 - Lenton, Timothy M. A1 - Folke, Carl A1 - Liverman, Diana A1 - Summerhayes, Colin P. A1 - Barnosky, Anthony D. A1 - Cornell, Sarah E. A1 - Crucifix, Michel A1 - Donges, Jonathan A1 - Fetzer, Ingo A1 - Lade, Steven J. A1 - Scheffer, Marten A1 - Winkelmann, Ricarda A1 - Schellnhuber, Hans Joachim T1 - Trajectories of the Earth System in the Anthropocene JF - Proceedings of the National Academy of Sciences of the United States of America N2 - We explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature rises and cause continued warming on a "Hothouse Earth" pathway even as human emissions are reduced. Crossing the threshold would lead to a much higher global average temperature than any interglacial in the past 1.2 million years and to sea levels significantly higher than at any time in the Holocene. We examine the evidence that such a threshold might exist and where it might be. If the threshold is crossed, the resulting trajectory would likely cause serious disruptions to ecosystems, society, and economies. Collective human action is required to steer the Earth System away from a potential threshold and stabilize it in a habitable interglacial-like state. Such action entails stewardship of the entire Earth System-biosphere, climate, and societies-and could include decarbonization of the global economy, enhancement of biosphere carbon sinks, behavioral changes, technological innovations, new governance arrangements, and transformed social values. KW - Earth System trajectories KW - climate change KW - Anthropocene KW - biosphere feedbacks KW - tipping elements Y1 - 2018 U6 - https://doi.org/10.1073/pnas.1810141115 SN - 0027-8424 VL - 115 IS - 33 SP - 8252 EP - 8259 PB - National Acad. of Sciences CY - Washington ER - TY - GEN A1 - Triet, Nguyen Van Khanh A1 - Dung, Nguyen Viet A1 - Merz, Bruno A1 - Apel, Heiko T1 - Towards risk-based flood management in highly productive paddy rice cultivation BT - concept development and application to the Mekong Delta T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Flooding is an imminent natural hazard threatening most river deltas, e.g. the Mekong Delta. An appropriate flood management is thus required for a sustainable development of the often densely populated regions. Recently, the traditional event-based hazard control shifted towards a risk management approach in many regions, driven by intensive research leading to new legal regulation on flood management. However, a large-scale flood risk assessment does not exist for the Mekong Delta. Particularly, flood risk to paddy rice cultivation, the most important economic activity in the delta, has not been performed yet. Therefore, the present study was developed to provide the very first insight into delta-scale flood damages and risks to rice cultivation. The flood hazard was quantified by probabilistic flood hazard maps of the whole delta using a bivariate extreme value statistics, synthetic flood hydrographs, and a large-scale hydraulic model. The flood risk to paddy rice was then quantified considering cropping calendars, rice phenology, and harvest times based on a time series of enhanced vegetation index (EVI) derived from MODIS satellite data, and a published rice flood damage function. The proposed concept provided flood risk maps to paddy rice for the Mekong Delta in terms of expected annual damage. The presented concept can be used as a blueprint for regions facing similar problems due to its generic approach. Furthermore, the changes in flood risk to paddy rice caused by changes in land use currently under discussion in the Mekong Delta were estimated. Two land-use scenarios either intensifying or reducing rice cropping were considered, and the changes in risk were presented in spatially explicit flood risk maps. The basic risk maps could serve as guidance for the authorities to develop spatially explicit flood management and mitigation plans for the delta. The land-use change risk maps could further be used for adaptive risk management plans and as a basis for a cost-benefit of the discussed land-use change scenarios. Additionally, the damage and risks maps may support the recently initiated agricultural insurance programme in Vietnam. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 931 KW - climate change KW - hazard analysis KW - sea level KW - Tho city KW - Vietnam KW - damage KW - uncertainty KW - models KW - floodplains KW - hydrology Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-446032 SN - 1866-8372 IS - 931 SP - 2859 EP - 2876 ER - TY - JOUR A1 - Hickmann, Thomas A1 - Widerberg, Oscar A1 - Lederer, Markus A1 - Pattberg, Philipp H. T1 - The United Nations Framework Convention on Climate Change Secretariat as an orchestrator in global climate policymaking JF - International review of administrative sciences : an international journal of comparative public administration N2 - Scholars have recently devoted increasing attention to the role and function of international bureaucracies in global policymaking. Some of them contend that international public officials have gained significant political influence in various policy fields. Compared to other international bureaucracies, the political leeway of the Secretariat of the United Nations Framework Convention on Climate Change has been considered rather limited. Due to the specific problem structure of the policy domain of climate change, national governments endowed this intergovernmental treaty secretariat with a relatively narrow mandate. However, this article argues that in the past few years, the United Nations Framework Convention on Climate Change Secretariat has gradually loosened its straitjacket and expanded its original spectrum of activity by engaging different sub-national and non-state actors into a policy dialogue using facilitative orchestration as a mode of governance. The present article explores the recent evolution of the United Nations Framework Convention on Climate Change Secretariat and investigates the way in which it initiates, guides, broadens and strengthens sub-national and non-state climate actions to achieve progress in the international climate negotiations.
Points for practitioners
The Secretariat of the United Nations Framework Convention on Climate Change has lately adopted new roles and functions in global climate policymaking. While previously seen as a rather technocratic body that, first and foremost, serves national governments, the Climate Secretariat increasingly interacts with sub-national governments, civil society organizations and private companies to push the global response to climate change forward. We contend that the Climate Secretariat can contribute to global climate policymaking by coordinating and steering the initiatives of non-nation-state actors towards coherence and good practice. KW - climate change KW - environmental policymaking KW - intergovernmental relations KW - international bureaucracies KW - sub-national and non-state actors Y1 - 2021 U6 - https://doi.org/10.1177/0020852319840425 SN - 0020-8523 SN - 1461-7226 VL - 87 IS - 1 SP - 21 EP - 38 PB - Sage CY - Los Angeles, Calif. [u.a.] ER - TY - JOUR A1 - De Frenne, Pieter A1 - Graae, Bente J. A1 - Brunet, Jörg A1 - Shevtsova, Anna A1 - De Schrijver, An A1 - Chabrerie, Olivier A1 - Cousins, Sara A. O. A1 - Decocq, Guillaume A1 - Diekmann, Martin A1 - Hermy, Martin A1 - Heinken, Thilo A1 - Kolb, Annette A1 - Nilsson, Christer A1 - Stanton, Sharon A1 - Verheyen, Kris T1 - The response of forest plant regeneration to temperature variation along a latitudinal gradient JF - Annals of botany N2 - The response of forest herb regeneration from seed to temperature variations across latitudes was experimentally assessed in order to forecast the likely response of understorey community dynamics to climate warming. Seeds of two characteristic forest plants (Anemone nemorosa and Milium effusum) were collected in natural populations along a latitudinal gradient from northern France to northern Sweden and exposed to three temperature regimes in growth chambers (first experiment). To test the importance of local adaptation, reciprocal transplants were also made of adult individuals that originated from the same populations in three common gardens located in southern, central and northern sites along the same gradient, and the resulting seeds were germinated (second experiment). Seedling establishment was quantified by measuring the timing and percentage of seedling emergence, and seedling biomass in both experiments. Spring warming increased emergence rates and seedling growth in the early-flowering forb A. nemorosa. Seedlings of the summer-flowering grass M. effusum originating from northern populations responded more strongly in terms of biomass growth to temperature than southern populations. The above-ground biomass of the seedlings of both species decreased with increasing latitude of origin, irrespective of whether seeds were collected from natural populations or from the common gardens. The emergence percentage decreased with increasing home-away distance in seeds from the transplant experiment, suggesting that the maternal plants were locally adapted. Decreasing seedling emergence and growth were found from the centre to the northern edge of the distribution range for both species. Stronger responses to temperature variation in seedling growth of the grass M. effusum in the north may offer a way to cope with environmental change. The results further suggest that climate warming might differentially affect seedling establishment of understorey plants across their distribution range and thus alter future understorey plant dynamics. KW - Anemone nemorosa KW - climate change KW - common garden KW - growth chambers KW - latitudinal gradient KW - local adaptation KW - Milium effusum KW - plant regeneration KW - range edges KW - recruitment KW - seedling establishment KW - temperature Y1 - 2012 U6 - https://doi.org/10.1093/aob/mcs015 SN - 0305-7364 VL - 109 IS - 5 SP - 1037 EP - 1046 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Schneider, Birgit A1 - Walsh, Lynda T1 - The politics of zoom BT - Problems with downscaling climate visualizations JF - Geo: Geography and Environment N2 - Following the mandate in the Paris Agreement for signatories to provide “climate services” to their constituents, “downscaled” climate visualizations are proliferating. But the process of downscaling climate visualizations does not neutralize the political problems with their synoptic global sources—namely, their failure to empower communities to take action and their replication of neoliberal paradigms of globalization. In this study we examine these problems as they apply to interactive climate‐visualization platforms, which allow their users to localize global climate information to support local political action. By scrutinizing the political implications of the “zoom” tool from the perspective of media studies and rhetoric, we add to perspectives of cultural cartography on the issue of scaling from our fields. Namely, we break down the cinematic trope of “zooming” to reveal how it imports the political problems of synopticism to the level of individual communities. As a potential antidote to the politics of zoom, we recommend a downscaling strategy of connectivity, which associates rather than reduces situated views of climate to global ones. KW - climate change KW - climate services KW - climate visualization KW - connectivity KW - downscaling KW - spherical KW - synopticism KW - zoom Y1 - 2019 U6 - https://doi.org/10.1002/geo2.70 SN - 2054-4049 VL - 6 IS - 1 PB - Wiley-Blackwell CY - Hoboken ER - TY - GEN A1 - Schneider, Birgit A1 - Walsh, Lynda T1 - The politics of zoom BT - Problems with downscaling climate visualizations T2 - Postprints der Universität Potsdam Philosophische Reihe N2 - Following the mandate in the Paris Agreement for signatories to provide “climate services” to their constituents, “downscaled” climate visualizations are proliferating. But the process of downscaling climate visualizations does not neutralize the political problems with their synoptic global sources—namely, their failure to empower communities to take action and their replication of neoliberal paradigms of globalization. In this study we examine these problems as they apply to interactive climate‐visualization platforms, which allow their users to localize global climate information to support local political action. By scrutinizing the political implications of the “zoom” tool from the perspective of media studies and rhetoric, we add to perspectives of cultural cartography on the issue of scaling from our fields. Namely, we break down the cinematic trope of “zooming” to reveal how it imports the political problems of synopticism to the level of individual communities. As a potential antidote to the politics of zoom, we recommend a downscaling strategy of connectivity, which associates rather than reduces situated views of climate to global ones. T3 - Zweitveröffentlichungen der Universität Potsdam : Philosophische Reihe - 159 KW - climate change KW - climate services KW - climate visualization KW - connectivity KW - downscaling KW - spherical KW - synopticism KW - zoom Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-424819 SN - 1866-8380 IS - 159 ER - TY - JOUR A1 - Levermann, Anders A1 - Clark, Peter U. A1 - Marzeion, Ben A1 - Milne, Glenn A. A1 - Pollard, David A1 - Radic, Valentina A1 - Robinson, Alexander T1 - The multimillennial sea-level commitment of global warming JF - Proceedings of the National Academy of Sciences of the United States of America N2 - Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sea-level rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m degrees C-1 and 1.2 m degrees C-1 of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m degrees C-1 within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales. KW - climate change KW - climate impacts KW - sea-level change Y1 - 2013 U6 - https://doi.org/10.1073/pnas.1219414110 SN - 0027-8424 VL - 110 IS - 34 SP - 13745 EP - 13750 PB - National Acad. of Sciences CY - Washington ER - TY - THES A1 - Fürstenau, Cornelia T1 - The impact of silvicultural strategies and climate change on carbon sequestration and other forest ecosystem functions T1 - Der Einfluss von Waldbewirtschaftungsstrategien und Klimawandel auf die Kohlenstoffspeicherung und andere Waldfunktionen N2 - Forests are a key resource serving a multitude of functions such as providing income to forest owners, supplying industries with timber, protecting water resources, and maintaining biodiversity. Recently much attention has been given to the role of forests in the global carbon cycle and their management for increased carbon sequestration as a possible mitigation option against climate change. Furthermore, the use of harvested wood can contribute to the reduction of atmospheric carbon through (i) carbon sequestration in wood products, (ii) the substitution of non-wood products with wood products, and (iii) through the use of wood as a biofuel to replace fossil fuels. Forest resource managers are challenged by the task to balance these multiple while simultaneously meeting economic requirements and taking into consideration the demands of stakeholder groups. Additionally, risks and uncertainties with regard to uncontrollable external variables such as climate have to be considered in the decision making process. In this study a scientific stakeholder dialogue with forest-related stakeholder groups in the Federal State of Brandenburg was accomplished. The main results of this dialogue were the definition of major forest functions (carbon sequestration, groundwater recharge, biodiversity, and timber production) and priority setting among them by the stakeholders using the pair-wise comparison technique. The impact of different forest management strategies and climate change scenarios on the main functions of forest ecosystems were evaluated at the Kleinsee management unit in south-east Brandenburg. Forest management strategies were simulated over 100 years using the forest growth model 4C and a wood product model (WPM). A current climate scenario and two climate change scenarios based on global circulation models (GCMs) HadCM2 and ECHAM4 were applied. The climate change scenario positively influenced stand productivity, carbon sequestration, and income. The impact on the other forest functions was small. Furthermore, the overall utility of forest management strategies were compared under the priority settings of stakeholders by a multi-criteria analysis (MCA) method. Significant differences in priority setting and the choice of an adequate management strategy were found for the environmentalists on one side and the more economy-oriented forest managers of public and private owned forests on the other side. From an ecological perspective, a conservation strategy would be preferable under all climate scenarios, but the business as usual management would also fit the expectations under the current climate. In contrast, a forest manager in public-owned forests or a private forest owner would prefer a management strategy with an intermediate thinning intensity and a high share of pine stands to enhance income from timber production while maintaining the other forest functions. The analysis served as an example for the combined application of simulation tools and a MCA method for the evaluation of management strategies under multi-purpose and multi-user settings with changing climatic conditions. Another focus was set on quantifying the overall effect of forest management on carbon sequestration in the forest sector and the wood industry sector plus substitution effects. To achieve this objective, the carbon emission reduction potential of material and energy substitution (Smat and Sen) was estimated based on a literature review. On average, for each tonne of dry wood used in a wood product substituting a non-wood product, 0.71 fewer tonnes of fossil carbon are emitted into to the atmosphere. Based on Smat and Sen, the calculation of the carbon emission reduction through substitution was implemented in the WPM. Carbon sequestration and substitution effects of management strategies were simulated at three local scales using the WPM and the forest growth models 4C (management unit level) or EFISCEN (federal state of Brandenburg and Germany). An investigation was conducted on the influence of uncertainties in the initialisation of the WPM, Smat, and basic conditions of the wood product sector on carbon sequestration. Results showed that carbon sequestration in the wood industry sector plus substitution effects exceeded sequestration in the forest sector. In contrast to the carbon pools in the forest sector, which acted as sink or source, the substitution effects continually reduced carbon emission as long as forests are managed and timber is harvested. The main climate protection function was investigated for energy substitution which accounted for about half of the total carbon sequestration, followed by carbon storage in landfills. In Germany, the absolute annual carbon sequestration in the forest and wood industry sector plus substitution effects was 19.9 Mt C. Over 50 years the wood industry sector contributed 70% of the total carbon sequestration plus substitution effects. N2 - Wälder beeinflussen in vielfältiger Weise unser Leben. Für den Waldbesitzer sind sie Einkommensquelle, die Holzindustrie versorgen sie mit dem Rohstoff, aus dem unzählige Dinge für den täglichen Bedarfs hergestellt werden, wie zum Beispiel Baumaterialien, Möbel, Gartengeräte, Spielzeug und Papier. Außerdem versorgen Wälder uns mit sauberem Grundwasser, sind Lebensraum für Pflanzen und Tiere und tragen somit zum Erhalt der Artenvielfalt bei. Nicht zuletzt beeinflussen Wälder das Klimasystem, da sie der Atmosphäre das Treibhausgas CO2 entziehen und Kohlenstoff in Biomasse und Boden speichern. Förster stehen nun vor der anspruchsvollen Aufgabe, eine Balance zwischen den vielfältigen und oft auch gegensätzlichen Waldfunktionen zu finden und die Ansprüche von Interessengruppen wahrzunehmen. Zusätzlich müssen im waldbaulichen Entscheidungsprozess Risiken und Unsicherheiten durch unberechenbare externe Faktoren, wie das Klima, beachtet werden. Ziel der Arbeit war es, den Einfluss von Klima und Waldbaustrategien auf Waldfunktionen zu untersuchen. Als Testgebiet fungierte das Revier Kleinsee im Südosten Brandenburgs, in dem Kiefern- und Eichenbestände vorherrschen. In einem wissenschaftlichen Dialog mit Angestellten der Forstbehörde, Privatwaldbesitzern, Vertretern von Naturschutzverbänden sowie Wissenschaftlern definierten die Teilnehmer die wichtigsten Waldfunktionen: Kohlenstoffspeicherung, Grundwasserneubildung, Biodiversität und Holzproduktion. Die Simulationen wurden mit Hilfe des Waldwachstumsmodells 4C und einem neu implementierten Holzproduktmodell (WPM) über einen Zeitraum von 100 Jahren durchgeführt. Dabei wurden den heutigen Klimabedingungen zwei Klimaänderungsszenarien gegenübergestellt, die auf den globalen Zirkulationsmodellen HadCM2 und ECHAM4 basieren. Es stellte sich heraus, dass unter den angenommenen Klimaänderungen das Wachstum der Bestände steigt und sich damit die Kohlenstoffspeicherung und der Ertrag aus Holzernten erhöht, wohingegen Biodiversität und Grundwasserneubildung nur sehr gering beeinflusst werden. Der Nutzen der Waldbewirtschaftungsstrategien für drei Interessensgruppen (Forstbehörde, private Waldbesitzer, Naturschutzvereine) wurde mit einer multikriteriellen Analysemethode bewertet. Dabei unterschieden sich die Rangfolge und Gewichtung der einzelnen Waldfunktionen sowie die daraus resultierende Wahl der Waldbaustrategien zwischen den Naturschützern einerseits sowie den stärker ökonomisch orientierten Landeswaldförstern und privaten Waldbesitzern anderseits. Naturschutzvereine bevorzugen das Einstellen der Waldbewirtschaftung, aber auch die aktuelle Waldbaustrategie, mit mäßiger Durchforstungsintensität und einem hohen Anteil an Eichenbeständen entspricht ihren Zielsetzungen. Dagegen lag die Präferenz der Landeswaldförster sowie privaten Waldbesitzer auf einer Walbaustrategie mit einem hohen Anteil an Kiefernbeständen, um den Ertrag unter Beachtung der anderen Waldfunktionen zu steigern. Als Fazit geht aus dieser Teilstudie hervor, dass die Bewertung von Waldbaustrategien hinsichtlich ihrer Eignung für eine multifunktionale Waldbewirtschaftung unter Beachtung von Ansprüchen verschiedener Interessengruppen und ungewissen klimatischen Bedingungen unter Verwendung von 4C und einer multikriteriellen Analysemethode sehr gut möglich ist. Besonderes Augenmerk galt dem Einfluss von Waldbaustrategien auf den Kohlenstoffkreislauf, wobei nicht nur die Kohlenstoffspeicherung im Wald, sondern auch in Holzprodukten, sowie die Verringerung von CO2-Emissionen durch energetische und stoffliche Nutzung von Holz betrachtet wurden. Die potentielle Reduktion von CO2-Emissionen durch das Ersetzen von Erzeugnissen und Energie aus nicht nachwachsenden Rohstoffen durch Holz (Smat und Sen) wurde basierend auf Daten verschiedener Studien geschätzt. Eine Sensitivitätsanalyse untersuchte Unsicherheiten bei der Initialisierung des WPMs und der Berechung von Smat. Verschiedene Szenarien führten zu einem besseren Verständnis dafür, wie sich Änderungen im Energiesektor und Holzproduktsektor auf das Potential, Kohlenstoff zu speichern bzw. CO2-Emissionen zu verringen auswirken. Die Ergebnisse zeigen, dass die Reduzierung von CO2-Emissionen im Holzproduktsektor durch die Nutzung von Holz als Werkstoff und Brennstoff höher ist als durch die Akkumulation von Kohlenstoff im Wald. Im Gegensatz zu den Kohlenstoffspeichern im Wald, die sowohl Quellen als auch Senken sein können, werden durch die Nutzung von Holz CO2-Emissionen verringert, solange im Zuge der Waldbewirtschaftung Holz für die Weiterverarbeitung zur Verfügung gestellt wird. Simulationen auf Bundesebene ergaben, dass in Deutschland die Forst- und Holzwirtschaft jährlich dazu beitragen die CO2-Emissionen um 19,9 Mt Kohlenstoff zu verringern, wobei 70% auf die Holzindustrie und den Substitutionseffekt entfallen. KW - Kohlenstoffspeicherung KW - Waldwachstumsmodell 4C KW - Holzprodukte KW - Klimawandel KW - carbon sequestration KW - forest growth model 4C KW - wood products KW - climate change Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-27657 ER - TY - JOUR A1 - Kalkuhl, Matthias A1 - Wenz, Leonie T1 - The impact of climate conditions on economic production BT - evidence from a global panel of regions JF - Journal of Environmental Economics and Management N2 - We present a novel data set of subnational economic output, Gross Regional Product (GRP), for more than 1500 regions in 77 countries that allows us to empirically estimate historic climate impacts at different time scales. Employing annual panel models, long-difference regressions and cross-sectional regressions, we identify effects on productivity levels and productivity growth. We do not find evidence for permanent growth rate impacts but we find robust evidence that temperature affects productivity levels considerably. An increase in global mean surface temperature by about 3.5°C until the end of the century would reduce global output by 7–14% in 2100, with even higher damages in tropical and poor regions. Updating the DICE damage function with our estimates suggests that the social cost of carbon from temperature-induced productivity losses is on the order of 73–142$/tCO2 in 2020, rising to 92–181$/tCO2 in 2030. These numbers exclude non-market damages and damages from extreme weather events or sea-level rise. KW - climate change KW - climate damages KW - climate impacts KW - growth regression KW - global warming KW - panel regression KW - cross-sectional regression KW - damage KW - function KW - social costs of carbon Y1 - 2020 U6 - https://doi.org/10.1016/j.jeem.2020.102360 SN - 0095-0696 SN - 1096-0449 VL - 103 PB - Elsevier CY - San Diego ER - TY - JOUR A1 - Stiegler, Jonas A1 - Pahl, Janice A1 - Guillen, Rafael Arce A1 - Ullmann, Wiebke A1 - Blaum, Niels T1 - The heat is on BT - impacts of rising temperature on the activity of a common European mammal JF - Frontiers in Ecology and Evolution N2 - Climate conditions severely impact the activity and, consequently, the fitness of wildlife species across the globe. Wildlife can respond to new climatic conditions, but the pace of human-induced change limits opportunities for adaptation or migration. Thus, how these changes affect behavior, movement patterns, and activity levels remains unclear. In this study, we investigate how extreme weather conditions affect the activity of European hares (Lepus europaeus) during their peak reproduction period. When hares must additionally invest energy in mating, prevailing against competitors, or lactating, we investigated their sensitivities to rising temperatures, wind speed, and humidity. To quantify their activity, we used the overall dynamic body acceleration (ODBA) calculated from tri-axial acceleration measurements of 33 GPS-collared hares. Our analysis revealed that temperature, humidity, and wind speed are important in explaining changes in activity, with a strong response for high temperatures above 25 & DEG;C and the highest change in activity during temperature extremes of over 35 & DEG;C during their inactive period. Further, we found a non-linear relationship between temperature and activity and an interaction of activity changes between day and night. Activity increased at higher temperatures during the inactive period (day) and decreased during the active period (night). This decrease was strongest during hot tropical nights. At a stage of life when mammals such as hares must substantially invest in reproduction, the sensitivity of females to extreme temperatures was particularly pronounced. Similarly, both sexes increased their activity at high humidity levels during the day and low wind speeds, irrespective of the time of day, while the effect of humidity was stronger for males. Our findings highlight the importance of understanding the complex relationships between extreme weather conditions and mammal behavior, critical for conservation and management. With ongoing climate change, extreme weather events such as heat waves and heavy rainfall are predicted to occur more often and last longer. These events will directly impact the fitness of hares and other wildlife species and hence the population dynamics of already declining populations across Europe. KW - activity KW - ODBA KW - animal tracking KW - European hare KW - extreme weather events KW - climate change Y1 - 2023 U6 - https://doi.org/10.3389/fevo.2023.1193861 SN - 2296-701X VL - 11 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Hickmann, Thomas A1 - Stehle, Fee T1 - The Embeddedness of Urban Climate Politics in Multilevel Governance BT - a Case Study of South Africa’s Major Cities JF - The journal of environment & development : a review of international policy N2 - Numerous scholars have lately highlighted the importance of cities in the global response to climate change. However, we still have little systematic knowledge on the evolution of urban climate politics in the Global South. In particular, we lack empirical studies that examine how local climate actions arise in political-administrative systems of developing and emerging economies. Therefore, this article adopts a multilevel governance perspective to explore the climate mitigation responses of three major cities in South Africa by looking at their vertical and horizontal integration in the wider governance framework. In the absence of a coherent national climate policy, Johannesburg, Cape Town, and Durban have developed distinct climate actions within their jurisdictions. In their effort to address climate change, transnational city networks have provided considerable technical support to these cities. Yet, substantial domestic political-economic obstacles hinder the three cities to develop a more ambitious stance on climate change. KW - climate change KW - developing and emerging economies KW - local climate policy making KW - multilevel governance KW - South Africa KW - transnational city networks Y1 - 2018 U6 - https://doi.org/10.1177/1070496518819121 SN - 1070-4965 SN - 1552-5465 VL - 28 IS - 1 SP - 54 EP - 77 PB - Sage Publ. CY - Thousand Oaks ER - TY - JOUR A1 - van Kleunen, Mark A1 - Essl, Franz A1 - Pergl, Jan A1 - Brundu, Giuseppe A1 - Carboni, Marta A1 - Dullinger, Stefan A1 - Early, Regan A1 - Gonzalez-Moreno, Pablo A1 - Groom, Quentin J. M. A1 - Hulme, Philip E. A1 - Kueffer, Christoph A1 - Kühn, Ingolf A1 - Maguas, Cristina A1 - Maurel, Noelie A1 - Novoa, Ana A1 - Parepa, Madalin A1 - Pysek, Petr A1 - Seebens, Hanno A1 - Tanner, Rob A1 - Touza, Julia A1 - Verbrugge, Laura A1 - Weber, Ewald A1 - Dawson, Wayne A1 - Kreft, Holger A1 - Weigelt, Patrick A1 - Winter, Marten A1 - Klonner, Guenther A1 - Talluto, Matthew V. A1 - Dehnen-Schmutz, Katharina T1 - The changing role of ornamental horticulture in alien plant invasions JF - Biological reviews N2 - The number of alien plants escaping from cultivation into native ecosystems is increasing steadily. We provide an overview of the historical, contemporary and potential future roles of ornamental horticulture in plant invasions. We show that currently at least 75% and 93% of the global naturalised alien flora is grown in domestic and botanical gardens, respectively. Species grown in gardens also have a larger naturalised range than those that are not. After the Middle Ages, particularly in the 18th and 19th centuries, a global trade network in plants emerged. Since then, cultivated alien species also started to appear in the wild more frequently than non-cultivated aliens globally, particularly during the 19th century. Horticulture still plays a prominent role in current plant introduction, and the monetary value of live-plant imports in different parts of the world is steadily increasing. Historically, botanical gardens - an important component of horticulture - played a major role in displaying, cultivating and distributing new plant discoveries. While the role of botanical gardens in the horticultural supply chain has declined, they are still a significant link, with one-third of institutions involved in retail-plant sales and horticultural research. However, botanical gardens have also become more dependent on commercial nurseries as plant sources, particularly in North America. Plants selected for ornamental purposes are not a random selection of the global flora, and some of the plant characteristics promoted through horticulture, such as fast growth, also promote invasion. Efforts to breed non-invasive plant cultivars are still rare. Socio-economical, technological, and environmental changes will lead to novel patterns of plant introductions and invasion opportunities for the species that are already cultivated. We describe the role that horticulture could play in mediating these changes. We identify current research challenges, and call for more research efforts on the past and current role of horticulture in plant invasions. This is required to develop science-based regulatory frameworks to prevent further plant invasions. KW - botanical gardens KW - climate change KW - horticulture KW - naturalised plants KW - ornamental plants KW - pathways KW - plant invasions KW - plant nurseries KW - trade KW - weeds Y1 - 2018 U6 - https://doi.org/10.1111/brv.12402 SN - 1464-7931 SN - 1469-185X VL - 93 IS - 3 SP - 1421 EP - 1437 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Wischnewski, Juliane A1 - Kramer, Annette A1 - Kong, Zhaochen A1 - Mackay, Anson W. A1 - Simpson, Gavin L. A1 - Mischke, Steffen A1 - Herzschuh, Ulrike T1 - Terrestrial and aquatic responses to climate change and human impact on the southeastern Tibetan Plateau during the past two centuries JF - Global change biology N2 - Rapid population growth and economic development have led to increased anthropogenic pressures on the Tibetan Plateau, causing significant land cover changes with potentially severe ecological consequences. To assess whether or not these pressures are also affecting the remote montane-boreal lakes on the SE Tibetan Plateau, fossil pollen and diatom data from two lakes were synthesized. The interplay of aquatic and terrestrial ecosystem response was explored in respect to climate variability and human activity over the past 200 years. Nonmetric multidimensional scaling and Procrustes rotation analysis were undertaken to determine whether pollen and diatom responses in each lake were similar and synchronous. Detrended canonical correspondence analysis was used to develop quantitative estimates of compositional species turnover. Despite instrumental evidence of significant climatic warming on the southeastern Plateau, the pollen and diatom records indicate very stable species composition throughout their profiles and show only very subtle responses to environmental changes over the past 200 years. The compositional species turnover (0.36-0.94 SD) is relatively low in comparison to the species reorganizations known from the periods during the mid-and early-Holocene (0.64-1.61 SD) on the SE Plateau, and also in comparison to turnover rates of sediment records from climate-sensitive regions in the circum arctic. Our results indicate that climatically induced ecological thresholds are not yet crossed, but that human activity has an increasing influence, particularly on the terrestrial ecosystem in our study area. Synergistic processes of post-Little Ice Age warming, 20th century climate warming and extensive reforestations since the 19th century have initiated a change from natural oak-pine forests to seminatural, likely less resilient pine-oak forests. Further warming and anthropogenic disturbances would possibly exceed the ecological threshold of these ecosystems and lead to severe ecological consequences. KW - climate change KW - compositional species turnover KW - diatoms KW - human impact KW - pollen KW - Procrustes rotation KW - Tibetan Plateau Y1 - 2011 U6 - https://doi.org/10.1111/j.1365-2486.2011.02474.x SN - 1354-1013 VL - 17 IS - 11 SP - 3376 EP - 3391 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Mtilatila, Lucy Mphatso Ng'ombe A1 - Bronstert, Axel A1 - Vormoor, Klaus Josef T1 - Temporal evaluation and projections of meteorological droughts in the Greater Lake Malawi Basin, Southeast Africa JF - Frontiers in water N2 - The study examined the potential future changes of drought characteristics in the Greater Lake Malawi Basin in Southeast Africa. This region strongly depends on water resources to generate electricity and food. Future projections (considering both moderate and high emission scenarios) of temperature and precipitation from an ensemble of 16 bias-corrected climate model combinations were blended with a scenario-neutral response surface approach to analyses changes in: (i) the meteorological conditions, (ii) the meteorological water balance, and (iii) selected drought characteristics such as drought intensity, drought months, and drought events, which were derived from the Standardized Precipitation and Evapotranspiration Index. Changes were analyzed for a near-term (2021-2050) and far-term period (2071-2100) with reference to 1976-2005. The effect of bias-correction (i.e., empirical quantile mapping) on the ability of the climate model ensemble to reproduce observed drought characteristics as compared to raw climate projections was also investigated. Results suggest that the bias-correction improves the climate models in terms of reproducing temperature and precipitation statistics but not drought characteristics. Still, despite the differences in the internal structures and uncertainties that exist among the climate models, they all agree on an increase of meteorological droughts in the future in terms of higher drought intensity and longer events. Drought intensity is projected to increase between +25 and +50% during 2021-2050 and between +131 and +388% during 2071-2100. This translates into +3 to +5, and +7 to +8 more drought months per year during both periods, respectively. With longer lasting drought events, the number of drought events decreases. Projected droughts based on the high emission scenario are 1.7 times more severe than droughts based on the moderate scenario. That means that droughts in this region will likely become more severe in the coming decades. Despite the inherent high uncertainties of climate projections, the results provide a basis in planning and (water-)managing activities for climate change adaptation measures in Malawi. This is of particular relevance for water management issues referring hydro power generation and food production, both for rain-fed and irrigated agriculture. KW - meteorological drought KW - drought intensity KW - climate change KW - drought KW - events KW - Lake Malawi KW - Shire River KW - drought projections KW - South-Eastern KW - Africa Y1 - 2022 U6 - https://doi.org/10.3389/frwa.2022.1041452 SN - 2624-9375 VL - 4 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Mtilatila, Lucy Mphatso Ng'ombe A1 - Bronstert, Axel A1 - Vormoor, Klaus Josef T1 - Temporal evaluation and projections of meteorological droughts in the Greater Lake Malawi Basin, Southeast Africa JF - Frontiers in Water N2 - The study examined the potential future changes of drought characteristics in the Greater Lake Malawi Basin in Southeast Africa. This region strongly depends on water resources to generate electricity and food. Future projections (considering both moderate and high emission scenarios) of temperature and precipitation from an ensemble of 16 bias-corrected climate model combinations were blended with a scenario-neutral response surface approach to analyses changes in: (i) the meteorological conditions, (ii) the meteorological water balance, and (iii) selected drought characteristics such as drought intensity, drought months, and drought events, which were derived from the Standardized Precipitation and Evapotranspiration Index. Changes were analyzed for a near-term (2021–2050) and far-term period (2071–2100) with reference to 1976–2005. The effect of bias-correction (i.e., empirical quantile mapping) on the ability of the climate model ensemble to reproduce observed drought characteristics as compared to raw climate projections was also investigated. Results suggest that the bias-correction improves the climate models in terms of reproducing temperature and precipitation statistics but not drought characteristics. Still, despite the differences in the internal structures and uncertainties that exist among the climate models, they all agree on an increase of meteorological droughts in the future in terms of higher drought intensity and longer events. Drought intensity is projected to increase between +25 and +50% during 2021–2050 and between +131 and +388% during 2071–2100. This translates into +3 to +5, and +7 to +8 more drought months per year during both periods, respectively. With longer lasting drought events, the number of drought events decreases. Projected droughts based on the high emission scenario are 1.7 times more severe than droughts based on the moderate scenario. That means that droughts in this region will likely become more severe in the coming decades. Despite the inherent high uncertainties of climate projections, the results provide a basis in planning and (water-)managing activities for climate change adaptation measures in Malawi. This is of particular relevance for water management issues referring hydro power generation and food production, both for rain-fed and irrigated agriculture. KW - meteorological drought KW - drought intensity KW - climate change KW - drought events KW - Lake Malawi KW - Shire River KW - drought projections KW - South-Eastern Africa Y1 - 2022 U6 - https://doi.org/10.3389/frwa.2022.1041452 SN - 2624-9375 SP - 1 EP - 16 PB - Frontiers Media S.A. CY - Lausanne, Schweiz ER - TY - GEN A1 - Mtilatila, Lucy Mphatso Ng'ombe A1 - Bronstert, Axel A1 - Vormoor, Klaus Josef T1 - Temporal evaluation and projections of meteorological droughts in the Greater Lake Malawi Basin, Southeast Africa T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The study examined the potential future changes of drought characteristics in the Greater Lake Malawi Basin in Southeast Africa. This region strongly depends on water resources to generate electricity and food. Future projections (considering both moderate and high emission scenarios) of temperature and precipitation from an ensemble of 16 bias-corrected climate model combinations were blended with a scenario-neutral response surface approach to analyses changes in: (i) the meteorological conditions, (ii) the meteorological water balance, and (iii) selected drought characteristics such as drought intensity, drought months, and drought events, which were derived from the Standardized Precipitation and Evapotranspiration Index. Changes were analyzed for a near-term (2021–2050) and far-term period (2071–2100) with reference to 1976–2005. The effect of bias-correction (i.e., empirical quantile mapping) on the ability of the climate model ensemble to reproduce observed drought characteristics as compared to raw climate projections was also investigated. Results suggest that the bias-correction improves the climate models in terms of reproducing temperature and precipitation statistics but not drought characteristics. Still, despite the differences in the internal structures and uncertainties that exist among the climate models, they all agree on an increase of meteorological droughts in the future in terms of higher drought intensity and longer events. Drought intensity is projected to increase between +25 and +50% during 2021–2050 and between +131 and +388% during 2071–2100. This translates into +3 to +5, and +7 to +8 more drought months per year during both periods, respectively. With longer lasting drought events, the number of drought events decreases. Projected droughts based on the high emission scenario are 1.7 times more severe than droughts based on the moderate scenario. That means that droughts in this region will likely become more severe in the coming decades. Despite the inherent high uncertainties of climate projections, the results provide a basis in planning and (water-)managing activities for climate change adaptation measures in Malawi. This is of particular relevance for water management issues referring hydro power generation and food production, both for rain-fed and irrigated agriculture. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1287 KW - meteorological drought KW - drought intensity KW - climate change KW - drought events KW - Lake Malawi KW - Shire River KW - drought projections KW - South-Eastern Africa Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-571284 SN - 1866-8372 IS - 1287 ER - TY - GEN A1 - Epp, Laura Saskia A1 - Kruse, Stefan A1 - Kath, Nadja J. A1 - Stoof-Leichsenring, Kathleen Rosemarie A1 - Tiedemann, Ralph A1 - Pestryakova, Luidmila Agafyevna A1 - Herzschuh, Ulrike T1 - Temporal and spatial patterns of mitochondrial haplotype and species distributions in Siberian larches inferred from ancient environmental DNA and modeling T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Changes in species' distributions are classically projected based on their climate envelopes. For Siberian forests, which have a tremendous significance for vegetation-climate feedbacks, this implies future shifts of each of the forest-forming larch (Larix) species to the north-east. However, in addition to abiotic factors, reliable projections must assess the role of historical biogeography and biotic interactions. Here, we use sedimentary ancient DNA and individual-based modelling to investigate the distribution of larch species and mitochondrial haplotypes through space and time across the treeline ecotone on the southern Taymyr peninsula, which at the same time presents a boundary area of two larch species. We find spatial and temporal patterns, which suggest that forest density is the most influential driver determining the precise distribution of species and mitochondrial haplotypes. This suggests a strong influence of competition on the species' range shifts. These findings imply possible climate change outcomes that are directly opposed to projections based purely on climate envelopes. Investigations of such fine-scale processes of biodiversity change through time are possible using paleoenvironmental DNA, which is available much more readily than visible fossils and can provide information at a level of resolution that is not reached in classical palaeoecology. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1052 KW - ecological genetics KW - ecological modelling KW - palaeoecology KW - plant ecology KW - climate change KW - introgression KW - temperature KW - treeline KW - vegetation KW - mitochondrial haplotypes KW - Siberian larch KW - larch species KW - range shifts KW - vegetation-climate feedbacks KW - ecosystems KW - impacts KW - dynamics Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-468352 SN - 1866-8372 IS - 1052 ER - TY - JOUR A1 - Huber, Veronika A1 - Krummenauer, Linda A1 - Peña-Ortiz, Cristina A1 - Lange, Stefan A1 - Gasparrini, Antonio A1 - Vicedo-Cabrera, Ana Maria A1 - Garcia-Herrera, Ricardo A1 - Frieler, Katja T1 - Temperature-related excess mortality in German cities at 2 °C and higher degrees of global warming JF - Environmental Research N2 - Background: Investigating future changes in temperature-related mortality as a function of global mean temperature (GMT) rise allows for the evaluation of policy-relevant climate change targets. So far, only few studies have taken this approach, and, in particular, no such assessments exist for Germany, the most populated country of Europe. Methods: We assess temperature-related mortality in 12 major German cities based on daily time-series of all-cause mortality and daily mean temperatures in the period 1993-2015, using distributed-lag non-linear models in a two-stage design. Resulting risk functions are applied to estimate excess mortality in terms of GMT rise relative to pre-industrial levels, assuming no change in demographics or population vulnerability. Results: In the observational period, cold contributes stronger to temperature-related mortality than heat, with overall attributable fractions of 5.49% (95%CI: 3.82-7.19) and 0.81% (95%CI: 0.72-0.89), respectively. Future projections indicate that this pattern could be reversed under progressing global warming, with heat-related mortality starting to exceed cold-related mortality at 3 degrees C or higher GMT rise. Across cities, projected net increases in total temperature-related mortality were 0.45% (95%CI: -0.02-1.06) at 3 degrees C, 1.53% (95%CI: 0.96-2.06) at 4 degrees C, and 2.88% (95%CI: 1.60-4.10) at 5 degrees C, compared to today's warming level of 1 degrees C. By contrast, no significant difference was found between projected total temperature-related mortality at 2 degrees C versus 1 degrees C of GMT rise. Conclusions: Our results can inform current adaptation policies aimed at buffering the health risks from increased heat exposure under climate change. They also allow for the evaluation of global mitigation efforts in terms of local health benefits in some of Germany's most populated cities. KW - temperature-related mortality KW - climate change KW - Future projections KW - Germany KW - global mean temperature Y1 - 2020 U6 - https://doi.org/10.1016/j.envres.2020.109447 SN - 0013-9351 SN - 1096-0953 VL - 186 SP - 1 EP - 10 PB - Elsevier CY - San Diego, California ER - TY - GEN A1 - Huber, Veronika A1 - Krummenauer, Linda A1 - Peña-Ortiz, Cristina A1 - Lange, Stefan A1 - Gasparrini, Antonio A1 - Vicedo-Cabrera, Ana Maria A1 - Garcia-Herrera, Ricardo A1 - Frieler, Katja T1 - Temperature-related excess mortality in German cities at 2 °C and higher degrees of global warming T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Background: Investigating future changes in temperature-related mortality as a function of global mean temperature (GMT) rise allows for the evaluation of policy-relevant climate change targets. So far, only few studies have taken this approach, and, in particular, no such assessments exist for Germany, the most populated country of Europe. Methods: We assess temperature-related mortality in 12 major German cities based on daily time-series of all-cause mortality and daily mean temperatures in the period 1993-2015, using distributed-lag non-linear models in a two-stage design. Resulting risk functions are applied to estimate excess mortality in terms of GMT rise relative to pre-industrial levels, assuming no change in demographics or population vulnerability. Results: In the observational period, cold contributes stronger to temperature-related mortality than heat, with overall attributable fractions of 5.49% (95%CI: 3.82-7.19) and 0.81% (95%CI: 0.72-0.89), respectively. Future projections indicate that this pattern could be reversed under progressing global warming, with heat-related mortality starting to exceed cold-related mortality at 3 degrees C or higher GMT rise. Across cities, projected net increases in total temperature-related mortality were 0.45% (95%CI: -0.02-1.06) at 3 degrees C, 1.53% (95%CI: 0.96-2.06) at 4 degrees C, and 2.88% (95%CI: 1.60-4.10) at 5 degrees C, compared to today's warming level of 1 degrees C. By contrast, no significant difference was found between projected total temperature-related mortality at 2 degrees C versus 1 degrees C of GMT rise. Conclusions: Our results can inform current adaptation policies aimed at buffering the health risks from increased heat exposure under climate change. They also allow for the evaluation of global mitigation efforts in terms of local health benefits in some of Germany's most populated cities. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1430 KW - temperature-related mortality KW - climate change KW - Future projections KW - Germany KW - global mean temperature Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-516511 SN - 1866-8372 ER - TY - JOUR A1 - De Frenne, Pieter A1 - Brunet, Jorg A1 - Shevtsova, Anna A1 - Kolb, Annette A1 - Graae, Bente J. A1 - Chabrerie, Olivier A1 - Cousins, Sara Ao A1 - Decocq, Guillaume A1 - De Schrijver, An A1 - Diekmann, Martin A1 - Gruwez, Robert A1 - Heinken, Thilo A1 - Hermy, Martin A1 - Nilsson, Christer A1 - Stanton, Sharon A1 - Tack, Wesley A1 - Willaert, Justin A1 - Verheyen, Kris T1 - Temperature effects on forest herbs assessed by warming and transplant experiments along a latitudinal gradient JF - Global change biology N2 - Slow-colonizing forest understorey plants are probably not able to rapidly adjust their distribution range following large-scale climate change. Therefore, the acclimation potential to climate change within their actual occupied habitats will likely be key for their short-and long-term persistence. We combined transplant experiments along a latitudinal gradient with open-top chambers to assess the effects of temperature on phenology, growth and reproductive performance of multiple populations of slow-colonizing understorey plants, using the spring flowering geophytic forb Anemone nemorosa and the early summer flowering grass Milium effusum as study species. In both species, emergence time and start of flowering clearly advanced with increasing temperatures. Vegetative growth (plant height, aboveground biomass) and reproductive success (seed mass, seed germination and germinable seed output) of A. nemorosa benefited from higher temperatures. Climate warming may thus increase future competitive ability and colonization rates of this species. Apart from the effects on phenology, growth and reproductive performance of M. effusum generally decreased when transplanted southwards (e. g., plant size and number of individuals decreased towards the south) and was probably more limited by light availability in the south. Specific leaf area of both species increased when transplanted southwards, but decreased with open-top chamber installation in A. nemorosa. In general, individuals of both species transplanted at the home site performed best, suggesting local adaptation. We conclude that contrasting understorey plants may display divergent plasticity in response to changing temperatures which may alter future understorey community dynamics. KW - climate change KW - common garden experiment KW - forest understorey KW - latitude KW - local adaptation KW - open-top chambers KW - phenotypic plasticity KW - pot experiment Y1 - 2011 U6 - https://doi.org/10.1111/j.1365-2486.2011.02449.x SN - 1354-1013 VL - 17 IS - 10 SP - 3240 EP - 3253 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Wenz, Leonie A1 - Kalkuhl, Matthias A1 - Steckel, Jan Christoph A1 - Creutzig, Felix T1 - Teleconnected food supply shocks JF - Environmental research letters N2 - The 2008-2010 food crisis might have been a harbinger of fundamental climate-induced food crises with geopolitical implications. Heat-wave-induced yield losses in Russia and resulting export restrictions led to increases in market prices for wheat across the Middle East, likely contributing to the Arab Spring. With ongoing climate change, temperatures and temperature variability will rise, leading to higher uncertainty in yields for major nutritional crops. Here we investigate which countries are most vulnerable to teleconnected supply-shocks, i.e. where diets strongly rely on the import of wheat, maize, or rice, and where a large share of the population is living in poverty. We find that the Middle East is most sensitive to teleconnected supply shocks in wheat, Central America to supply shocks in maize, and Western Africa to supply shocks in rice. Weighing with poverty levels, Sub-Saharan Africa is most affected. Altogether, a simultaneous 10% reduction in exports of wheat, rice, and maize would reduce caloric intake of 55 million people living in poverty by about 5%. Export bans in major producing regions would put up to 200 million people below the poverty line at risk, 90% of which live in Sub-Saharan Africa. Our results suggest that a region-specific combination of national increases in agricultural productivity and diversification of trade partners and diets can effectively decrease future food security risks. KW - food security KW - trade shocks KW - vulnerability KW - climate change KW - teleconnections Y1 - 2016 U6 - https://doi.org/10.1088/1748-9326/11/3/035007 SN - 1748-9326 VL - 11 PB - IOP Publ. Ltd. CY - Bristol ER - TY - THES A1 - Lohmann, Dirk T1 - Sustainable management of semi-arid African savannas under environmental and political change T1 - Nachhaltige Nutzung semiarider Savannen in Afrika unter dem Einfluss von klimatischem und politischem Wandel N2 - Drylands cover about 40% of the earth’s land surface and provide the basis for the livelihoods of 38% of the global human population. Worldwide, these ecosystems are prone to heavy degradation. Increasing levels of dryland degradation result a strong decline of ecosystem services. In addition, in highly variable semi-arid environments changing future environmental conditions will potentially have severe consequences for productivity and ecosystem dynamics. Hence, global efforts have to be made to understand the particular causes and consequences of dryland degradation and to promote sustainable management options for semi-arid and arid ecosystems in a changing world. Here I particularly address the problem of semi-arid savanna degradation, which mostly occurs in form of woody plant encroachment. At this, I aim at finding viable sustainable management strategies and improving the general understanding of semi-arid savanna vegetation dynamics under conditions of extensive livestock production. Moreover, the influence of external forces, i.e. environmental change and land reform, on the use of savanna vegetation and on the ecosystem response to this land use is assessed. Based on this I identify conditions and strategies that facilitate a sustainable use of semi-arid savanna rangelands in a changing world. I extended an eco-hydrological model to simulate rangeland vegetation dynamics for a typical semi-arid savanna in eastern Namibia. In particular, I identified the response of semi-arid savanna vegetation to different land use strategies (including fire management) also with regard to different predicted precipitation, temperature and CO2 regimes. Not only environmental but also economic and political constraints like e.g. land reform programmes are shaping rangeland management strategies. Hence, I aimed at understanding the effects of the ongoing process of land reform in southern Africa on land use and the semi-arid savanna vegetation. Therefore, I developed and implemented an agent-based ecological-economic modelling tool for interactive role plays with land users. This tool was applied in an interdisciplinary empirical study to identify general patterns of management decisions and the between-farm cooperation of land reform beneficiaries in eastern Namibia. The eco-hydrological simulations revealed that the future dynamics of semi-arid savanna vegetation strongly depend on the respective climate change scenario. In particular, I found that the capacity of the system to sustain domestic livestock production will strongly depend on changes in the amount and temporal distribution of precipitation. In addition, my simulations revealed that shrub encroachment will become less likely under future climatic conditions although positive effects of CO2 on woody plant growth and transpiration have been considered. While earlier studies predicted a further increase in shrub encroachment due to increased levels of atmospheric CO2, my contrary finding is based on the negative impacts of temperature increase on the drought sensitive seedling germination and establishment of woody plant species. Further simulation experiments revealed that prescribed fires are an efficient tool for semi-arid rangeland management, since they suppress woody plant seedling establishment. The strategies tested have increased the long term productivity of the savanna in terms of livestock production and decreased the risk for shrub encroachment (i.e. savanna degradation). This finding refutes the views promoted by existing studies, which state that fires are of minor importance for the vegetation dynamics of semi-arid and arid savannas. Again, the difference in predictions is related to the bottleneck at the seedling establishment stage of woody plants, which has not been sufficiently considered in earlier studies. The ecological-economic role plays with Namibian land reform beneficiaries showed that the farmers made their decisions with regard to herd size adjustments according to economic but not according to environmental variables. Hence, they do not manage opportunistically by tracking grass biomass availability but rather apply conservative management strategies with low stocking rates. This implies that under the given circumstances the management of these farmers will not per se cause (or further worsen) the problem of savanna degradation and shrub encroachment due to overgrazing. However, as my results indicate that this management strategy is rather based on high financial pressure, it is not an indicator for successful rangeland management. Rather, farmers struggle hard to make any positive revenue from their farming business and the success of the Namibian land reform is currently disputable. The role-plays also revealed that cooperation between farmers is difficult even though obligatory due to the often small farm sizes. I thus propose that cooperation needs to be facilitated to improve the success of land reform beneficiaries. N2 - Semiaride (halbtrockene) Savannen bedecken große Teile der Erdoberfläche und sichern die Lebensgrundlage von vielen Millionen Menschen. Die häufigste Form der Landnutzung in diesen Trockengebieten ist die Produktion von Vieh in extensiver Weidelandbewirtschaftung. In Folge klimatischer Veränderungen und als Konsequenz aus der teils intensiven Beweidung dieser Trockengebiete kommt es häufig zur Degradierung derselben in Form einer Zunahme von ‚unerwünschter‘ holziger Vegetation auf Kosten von futterverwertbaren Gräsern. Dieser als Verbuschung bezeichnete Prozess hat schwere negative Auswirkungen auf die betroffenen Ökosysteme und ist die Ursache für einen zunehmenden Rückgang der ökonomischen Leistungsfähigkeit der betroffenen Betriebe. In meiner Dissertation befasse ich mich mit den Auswirkungen von Klimawandel und politischen Veränderungen auf die Savannenvegetation im südlichen Afrika und auf die Möglichkeiten für die Nutzung dieser Ökosysteme in Form von Viehwirtschaft. Hierbei möchte ich sowohl das allgemeine Verständnis der ökologischen Zusammenhänge verbessern, als auch Strategien für die nachhaltige Nutzung der Savannen identifizieren und bewerten. Da nicht nur ökologische, sondern auch ökonomische und politische Einflussfaktoren, wie zum Beispiel die umfangreichen Landumverteilungen im Rahmen der Bodenreform im südlichen Afrika auf die tatsächliche Landnutzung wirken, habe ich im Rahmen der Dissertation zudem untersucht, nach welchen Umwelt und Kapitalvariablen sich die Farmer, welche Ihr Land im Rahmen der Bodenreform zugeteilt bekommen haben, bei Ihren Entscheidungen richten. Methodisch verwende ich verschiedene Simulationsmodelle, welche zur Untersuchung der langfristigen Veränderungen von verschiedensten Szenarien (Klimawandel, Landnutzung) geeignet sind. Hierbei habe ich teilweise bestehende Modelle angepasst, aber auch ein neues Modell, welches zur Befragung von Farmern in Namibia verwendet wurde, entwickelt. Meine Dissertation führt im Wesentlichen zu vier Erkenntnissen: Erstens, zeigen meine Ergebnisse, welche große Bedeutung die spezifischen ökologischen Eigenschaften der Bäume und Sträucher in semiariden Savannen für die Vorhersage der Entwicklung dieser Systeme unter Klimawandel hat. Hierbei zeigte sich, dass insbesondere die Sensitivität der Keimlinge gegenüber Trockenheit und Feuer eine entscheidende Rolle spielt. Daraus folgt die zweite wesentliche Erkenntnis: Feuer eignet sich in herausragender Weise, um halbtrockene Savannen vor der Verbuschung zu bewahren. Drittens haben die Rollenspiele mit Farmern in Namibia gezeigt, dass deren Entscheidungen im Wesentlichen von finanziellen Schwierigkeiten und nicht von Umwelteinflüssen getrieben werden. Dennoch zeigten meine Ergebnisse, dass diese Farmer mit Ihrem derzeitigen Verhalten wahrscheinlich nicht zur weiteren Degradierung der Savannenvegetation beitragen. Die vierte, und mit am bedeutendste Erkenntnis aus meiner Arbeit ist, dass konservative Beweidungsstrategien mit geringen und konstanten Viehdichten notwendig sind um semiaride Savannen dauerhaft in ökologisch und ökonomisch nachhaltiger Weise zu Nutzen. KW - Savanne KW - nachhaltige Landnutzung KW - ökohydrologische Modellierung KW - Land Reform KW - Klimawandel KW - Savanna KW - sustainable land use KW - eco-hydrological modelling KW - land reform KW - climate change Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-65069 ER - TY - JOUR A1 - Huber, Robert A1 - Rigling, Andreas A1 - Bebi, Peter A1 - Brand, Fridolin Simon A1 - Briner, Simon A1 - Buttler, Alexandre A1 - Elkin, Che A1 - Gillet, Francois A1 - Gret-Regamey, Adrienne A1 - Hirschi, Christian A1 - Lischke, Heike A1 - Scholz, Roland Werner A1 - Seidl, Roman A1 - Spiegelberger, Thomas A1 - Walz, Ariane A1 - Zimmermann, Willi A1 - Bugmann, Harald T1 - Sustainable land use in Mountain Regions under global change synthesis across scales and disciplines JF - Ecology and society : a journal of integrative science for resilience and sustainability N2 - Mountain regions provide essential ecosystem goods and services (EGS) for both mountain dwellers and people living outside these areas. Global change endangers the capacity of mountain ecosystems to provide key services. The Mountland project focused on three case study regions in the Swiss Alps and aimed to propose land-use practices and alternative policy solutions to ensure the provision of key EGS under climate and land-use changes. We summarized and synthesized the results of the project and provide insights into the ecological, socioeconomic, and political processes relevant for analyzing global change impacts on a European mountain region. In Mountland, an integrative approach was applied, combining methods from economics and the political and natural sciences to analyze ecosystem functioning from a holistic human-environment system perspective. In general, surveys, experiments, and model results revealed that climate and socioeconomic changes are likely to increase the vulnerability of the EGS analyzed. We regard the following key characteristics of coupled human-environment systems as central to our case study areas in mountain regions: thresholds, heterogeneity, trade-offs, and feedback. Our results suggest that the institutional framework should be strengthened in a way that better addresses these characteristics, allowing for (1) more integrative approaches, (2) a more network-oriented management and steering of political processes that integrate local stakeholders, and (3) enhanced capacity building to decrease the identified vulnerability as central elements in the policy process. Further, to maintain and support the future provision of EGS in mountain regions, policy making should also focus on project-oriented, cross-sectoral policies and spatial planning as a coordination instrument for land use in general. KW - adaptive management KW - climate change KW - ecosystem services KW - experiments KW - interdisciplinary research KW - land-use change KW - modeling KW - transdisciplinary research Y1 - 2013 U6 - https://doi.org/10.5751/ES-05499-180336 SN - 1708-3087 VL - 18 IS - 3 PB - Resilience Alliance CY - Wolfville ER - TY - JOUR A1 - Coch, Caroline A1 - Lamoureux, Scott F. A1 - Knoblauch, Christian A1 - Eischeid, Isabell A1 - Fritz, Michael A1 - Obu, Jaroslav A1 - Lantuit, Hugues T1 - Summer rainfall dissolved organic carbon, solute, and sediment fluxes in a small Arctic coastal catchment on Herschel Island (Yukon Territory, Canada) JF - Artic science N2 - Coastal ecosystems in the Arctic are affected by climate change. As summer rainfall frequency and intensity are projected to increase in the future, more organic matter, nutrients and sediment could bemobilized and transported into the coastal nearshore zones. However, knowledge of current processes and future changes is limited. We investigated streamflow dynamics and the impacts of summer rainfall on lateral fluxes in a small coastal catchment on Herschel Island in the western Canadian Arctic. For the summer monitoring periods of 2014-2016, mean dissolved organic matter flux over 17 days amounted to 82.7 +/- 30.7 kg km(-2) and mean total dissolved solids flux to 5252 +/- 1224 kg km(-2). Flux of suspended sediment was 7245 kg km(-2) in 2015, and 369 kg km(-2) in 2016. We found that 2.0% of suspended sediment was composed of particulate organic carbon. Data and hysteresis analysis suggest a limited supply of sediments; their interannual variability is most likely caused by short-lived localized disturbances. In contrast, our results imply that dissolved organic carbon is widely available throughout the catchment and exhibits positive linear relationship with runoff. We hypothesize that increased projected rainfall in the future will result in a similar increase of dissolved organic carbon fluxes. KW - permafrost KW - hydrology KW - lateral fluxes KW - hysteresis KW - climate change Y1 - 2018 U6 - https://doi.org/10.1139/as-2018-0010 SN - 2368-7460 VL - 4 IS - 4 SP - 750 EP - 780 PB - Canadian science publishing CY - Ottawa ER - TY - GEN A1 - Köchy, Martin T1 - Stochastic time series of daily precipitation for the interior of Israel N2 - This contribution describes a generator of stochastic time series of daily precipitation for the interior of Israel from c. 90 to 900 mm mean annual precipitation (MAP) as a tool for studies of daily rain variability. The probability of rainfall on a given day of the year is described by a regular Gaussian peak curve function. The amount of rain is drawn randomly from an exponential distribution whose mean is the daily mean rain amount (averaged across years for each day of the year) described by a flattened Gaussian peak curve. Parameters for the curves have been calculated from monthly aggregated, long-term rain records from seven meteorological stations. Parameters for arbitrary points on the MAP gradient are calculated from a regression equation with MAP as the only independent variable. The simple structure of the generator allows it to produce time series with daily rain patterns that are projected under climate change scenarios and simultaneously control MAP. Increasing within-year variability of daily precipitation amounts also increases among-year variability of MAP as predicted by global circulation models. Thus, the time series incorporate important characteristics for climate change research and represent a flexible tool for simulations of daily vegetation or surface hydrology dynamics. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 029 KW - stochastische Zeitreihen KW - täglicher Niederschlag KW - Israel KW - Klimawandel KW - stochastic time series KW - daily precipitation KW - Israel KW - climate change Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-13155 ER - TY - THES A1 - Schibalski, Anett T1 - Statistical and process-based models for understanding species distributions in changing environments T1 - Statistische und prozessbasierte Modelle für die Verbreitung von Arten unter Umweltänderungen N2 - Understanding the distribution of species is fundamental for biodiversity conservation, ecosystem management, and increasingly also for climate impact assessment. The presence of a species in a given site depends on physiological limitations (abiotic factors), interactions with other species (biotic factors), migratory or dispersal processes (site accessibility) as well as the continuing effects of past events, e.g. disturbances (site legacy). Existing approaches to predict species distributions either (i) correlate observed species occurrences with environmental variables describing abiotic limitations, thus ignoring biotic interactions, dispersal and legacy effects (statistical species distribution model, SDM); or (ii) mechanistically model the variety of processes determining species distributions (process-based model, PBM). SDMs are widely used due to their easy applicability and ability to handle varied data qualities. But they fail to reproduce the dynamic response of species distributions to changing conditions. PBMs are expected to be superior in this respect, but they need very specific data unavailable for many species, and are often more complex and require more computational effort. More recently, hybrid models link the two approaches to combine their respective strengths. In this thesis, I apply and compare statistical and process-based approaches to predict species distributions, and I discuss their respective limitations, specifically for applications in changing environments. Detailed analyses of SDMs for boreal tree species in Finland reveal that nonclimatic predictors - edaphic properties and biotic interactions - are important limitations at the treeline, contesting the assumption of unrestricted, climatically induced range expansion. While the estimated SDMs are successful within their training data range, spatial and temporal model transfer fails. Mapping and comparing sampled predictor space among data subsets identifies spurious extrapolation as the plausible explanation for limited model transferability. Using these findings, I analyze the limited success of an established PBM (LPJ-GUESS) applied to the same problem. Examination of process representation and parameterization in the PBM identifies implemented processes to adjust (competition between species, disturbance) and missing processes that are crucial in boreal forests (nutrient limitation, forest management). Based on climatic correlations shifting over time, I stress the restricted temporal transferability of bioclimatic limits used in LPJ-GUESS and similar PBMs. By critically assessing the performance of SDM and PBM in this application, I demonstrate the importance of understanding the limitations of the applied methods. As a potential solution, I add a novel approach to the repertoire of existing hybrid models. By simulation experiments with an individual-based PBM which reproduces community dynamics resulting from biotic factors, dispersal and legacy effects, I assess the resilience of coastal vegetation to abrupt hydrological changes. According to the results of the resilience analysis, I then modify temporal SDM predictions, thereby transferring relevant process detail from PBM to SDM. The direction of knowledge transfer from PBM to SDM avoids disadvantages of current hybrid models and increases the applicability of the resulting model in long-term, large-scale applications. A further advantage of the proposed framework is its flexibility, as it is readily extended to other model types, disturbance definitions and response characteristics. Concluding, I argue that we already have a diverse range of promising modelling tools at hand, which can be refined further. But most importantly, they need to be applied more thoughtfully. Bearing their limitations in mind, combining their strengths and openly reporting underlying assumptions and uncertainties is the way forward. N2 - Wissen über die Verbreitung von Arten ist fundamental für die Erhaltung von Biodiversität, das Management von Ökosystemen und zunehmend auch für die Abschätzung der Folgen des Klimawandels. Das Vorkommen einer Art an einem Standort hängt ab von: physiologischen Grenzwerten (abiotischen Faktoren), Interaktionen mit anderen Arten (biotischen Faktoren), Ausbreitungsprozessen (Erreichbarkeit des Standorts) sowie Nachwirkungen vergangener Ereignisse, z.B. Störungen (Standortgeschichte). Modellansätze zur Vorhersage von Artverbreitungen (i) korrelieren entweder beobachtete Artvorkommen mit abiotischen Umweltvariablen und ignorieren damit biotische Interaktionen, Ausbreitung und Nachwirkungen (statistische Artverbreitungsmodelle, SDM); oder (ii) sie modellieren mechanistisch, wie sich die verschiedenen Prozesse auf Arten auswirken (prozessbasierte Modelle, PBM). SDMs sind weitverbreitet, da sie einfach anzuwenden sind und verschiedenste Datenqualitäten akzeptieren. Aber sie beschreiben nicht korrekt, wie Arten dynamisch auf Umweltänderungen reagieren. PBMs sind ihnen in dieser Hinsicht überlegen. Allerdings benötigen diese sehr spezifische Daten, welche für viele Arten nicht verfügbar sind. Zudem sind sie oft komplexer und benötigen mehr Rechenkapazität. Relativ neu ist der Ansatz des Hybridmodells, welches statistische und prozessbasierte Modelle verknüpft und so ihre jeweiligen Stärken vereint. In dieser Arbeit, nutze ich sowohl statistische als auch prozessbasierte Modelle, um die Verbreitung von Arten vorherzusagen, und ich diskutiere ihre jeweiligen Schwächen, besonders für die Anwendung im Klimawandelkontext. Eine detaillierte Analyse der SDMs für boreale Baumarten in Finnland zeigt, dass nicht-klimatische Variablen - Bodeneigenschaften und biotische Interaktionen - wichtige Faktoren an der Baumgrenze sind und daher die Reaktion von Arten auf Klimaänderungen beeinflussen. Während die SDMs innerhalb der Wertebereiche ihrer Trainingsdatensätze erfolgreich sind, scheitern Versuche, die Modelle auf andere Regionen oder in die Zukunft zu übertragen. Die Visualisierung und der Vergleich des abgedeckten Umweltraums zwischen den Teildatensätzen liefert eine plausible Erklärung: Extrapolation. Basierend auf diesen Ergebnissen, analysiere ich den bedingten Erfolg eines etablierten PBMs (LPJ-GUESS), das ich auf dieselbe Fragestellung anwende. Die Untersuchung der Prozessbeschreibungen im Modell sowie der Parametrisierung zeigen, dass bereits implementierte Prozesse angepasst werden müssen (Konkurrenz, Störungen) und dass für boreale Wälder entscheidende Prozesse fehlen (Nährstoffe, Bewirtschaftung). Mithilfe von klimatischen Schwellenwerten, die sich über die Zeit verschieben, betone ich die eingeschränkte Übertragbarkeit von bioklimatischen Grenzwerten in LPJ-GUESS und ähnlichen PBMs. Indem ich die Performance beider Methoden in dieser Anwendung kritisch beleuchte, zeige ich, wie wichtig es ist, sich der Grenzen jedes Modellansatzes bewusst zu sein. Als Lösungsmöglichkeit füge ich dem bestehenden Repertoire der Hybridmodelle einen neuen Ansatz hinzu. Mithilfe von Simulationsexperimenten mit einem individuenbasierten PBM, das erfolgreich die Dynamik von Artgemeinschaften beschreibt (resultierend aus biotischen Faktoren, Ausbreitung und Nachwirkungen), untersuche ich die Resilienz von Küstenvegetation auf abrupte Änderungen der Hydrologie. Entsprechend der Ergebnisse dieser Resilienzanalyse passe ich die zeitlichen Vorhersagen eines SDMs an und übertrage so das nötige Prozesswissen von PBM zu SDM. Die Übertragungsrichtung von PBM zu SDM umgeht die Nachteile bestehender Hybridmodelle und verbessert die Anwendbarkeit für langfristige, großflächige Berechnungen. Ein weiterer Vorteil des vorgestellten Konzepts ist seine Flexibilität, denn es lässt sich einfach auf andere Modellarten, andere Definitionen von Umweltstörungen sowie andere Vorhersagegrößen anwenden. Zusammenfassend argumentiere ich, dass uns bereits vielfältige, erfolgversprechende Modellansätze zur Verfügung stehen, die noch weiterentwickelt werden können. Vor allem aber müssen sie mit mehr Bedacht angewendet werden. Voran kommen wir, indem wir die Schwächen der Ansätze berücksichtigen, ihre Stärken in Hybridmodellen kombinieren und die zugrunde liegenden Annahmen und damit verbundene Unsicherheiten deutlich machen. KW - species distribution KW - Artverbreitung KW - climate change KW - Klimawandel KW - hybrid model KW - Hybridmodell Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-401482 ER - TY - THES A1 - Hanschmann, Raffael Tino T1 - Stalling the engine? EU climate politics after the ‘Great Recession’ T1 - Den Motor abgewürgt? EU-Klimapolitik nach der Großen Rezession BT - investigating the impact of economic shocks on EU climate policy-making in three case studies BT - eine Untersuchung des Einflusses von Wirtschaftskrisen auf Prozesse in der EU-Klimapolitik in drei Fallstudien N2 - This dissertation investigates the impact of the economic and fiscal crisis starting in 2008 on EU climate policy-making. While the overall number of adopted greenhouse gas emission reduction policies declined in the crisis aftermath, EU lawmakers decided to introduce new or tighten existing regulations in some important policy domains. Existing knowledge about the crisis impact on EU legislative decision-making cannot explain these inconsistencies. In response, this study develops an actor-centred conceptual framework based on rational choice institutionalism that provides a micro-level link to explain how economic crises translate into altered policy-making patterns. The core theoretical argument draws on redistributive conflicts, arguing that tensions between ‘beneficiaries’ and ‘losers’ of a regulatory initiative intensify during economic crises and spill over to the policy domain. To test this hypothesis and using social network analysis, this study analyses policy processes in three case studies: The introduction of carbon dioxide emission limits for passenger cars, the expansion of the EU Emissions Trading System to aviation, and the introduction of a regulatory framework for biofuels. The key finding is that an economic shock causes EU policy domains to polarise politically, resulting in intensified conflict and more difficult decision-making. The results also show that this process of political polarisation roots in the industry that is the subject of the regulation, and that intergovernmental bargaining among member states becomes more important, but also more difficult in times of crisis. N2 - Diese Dissertation untersucht den Einfluss der in 2008 beginnenden globalen Wirtschaftskrise auf die Prozesse der EU-Klimapolitik. Während die Zahl der verabschiedeten Gesetze zur Treibhausgasreduktion nach Krisenausbruch insgesamt sank, entschieden die EU-Gesetzgeber, in mehreren wichtigen Politikfeldern neue Regulierungen einzuführen oder existierende zu verschärfen. Bestehendes Wissen zum Einfluss der Krise auf EU-Gesetzgebungsprozesse kann diese Inkonsistenzen nicht erklären. Daher entwickelt diese Arbeit ein auf Rational-Choice-Institutionalismus basierendes konzeptionelles Gerüst, das auf der Mikro-Ebene eine kausale Verbindung zwischen Wirtschaftskrise und veränderten Politikprozessen herstellt. Das zentrale theoretische Argument beruht auf Verteilungskonflikten innerhalb der regulierten Wirtschaftsbranchen: Die Spannung zwischen „Nutznießern“ und „Verlierern“ einer geplanten Regulierung intensiviert sich in Krisenzeiten und setzt sich im politischen Raum fort. Diese Hypothese wird an drei Fallstudien mittels sozialer Netzwerkanalyse getestet. Die drei Fallstudien untersuchen politische Entscheidungsprozesse in den folgenden EU-Politikfeldern: Kohlenstoffdioxid-Emissionsgrenzen für PKW, die Ausweitung des Emissionshandels auf Flugverkehr und die Einführung eines Regulierungsrahmens für Biokraftstoffe. Die wichtigste Erkenntnis der Untersuchung ist, dass makroökonomische Schocks eine Polarisierung der politischen Interessen innerhalb eines Politikfeldes auslösen, dadurch Konflikte intensivieren und letztlich Entscheidungsfindungen erschweren. Die Ergebnisse zeigen zudem, dass dieser Polarisierungsprozess in der regulierten Wirtschaftsbranche wurzelt. Außerdem werden Verhandlungen zwischen den Regierungen der Mitgliedsstaaten in Krisenzeiten wichtiger, aber auch schwieriger.  KW - EU KW - European Union KW - policy-making KW - network analysis KW - policy preferences KW - economic crisis KW - crisis KW - climate KW - climate change KW - climate policy KW - climate politics KW - environmental policy KW - EU KW - Europäische Union KW - Politikgestaltung KW - Netzwerkanalyse KW - Politikpräferenzen KW - Wirtschaftskrise KW - Krise KW - Klima KW - Klimawandel KW - Klimapolitik KW - Umweltpolitik Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-440441 ER - TY - JOUR A1 - Grimm-Seyfarth, Annegret A1 - Mihoub, Jean-Baptiste A1 - Gruber, Bernd A1 - Henle, Klaus T1 - Some like it hot BT - from individual to population responses of an arboreal arid-zone gecko to local and distant climate JF - Ecological monographs N2 - Accumulating evidence has demonstrated considerable impact of climate change on biodiversity, with terrestrial ectotherms being particularly vulnerable. While climate-induced range shifts are often addressed in the literature, little is known about the underlying ecological responses at individual and population levels. Using a 30-yr monitoring study of the long-living nocturnal gecko Gehyra variegata in arid Australia, we determined the relative contribution of climatic factors acting locally (temperature, rainfall) or distantly (La Nina induced flooding) on ecological processes ranging from traits at the individual level (body condition, body growth) to the demography at population level (survival, sexual maturity, population sizes). We also investigated whether thermoregulatory activity during both active (night) and resting (daytime) periods of the day can explain these responses. Gehyra variegata responded to local and distant climatic effects. Both high temperatures and high water availability enhanced individual and demographic parameters. Moreover, the impact of water availability was scale independent as local rainfall and La Nina induced flooding compensated each other. When water availability was low, however, extremely high temperatures delayed body growth and sexual maturity while survival of individuals and population sizes remained stable. This suggests a trade-off with traits at the individual level that may potentially buffer the consequences of adverse climatic conditions at the population level. Moreover, hot temperatures did not impact nocturnal nor diurnal behavior. Instead, only cool temperatures induced diurnal thermoregulatory behavior with individuals moving to exposed hollow branches and even outside tree hollows for sun-basking during the day. Since diurnal behavioral thermoregulation likely induced costs on fitness, this could decrease performance at both individual and population level under cool temperatures. Our findings show that water availability rather than high temperature is the limiting factor in our focal population of G.variegata. In contrast to previous studies, we stress that drier rather than warmer conditions are expected to be detrimental for nocturnal desert reptiles. Identifying the actual limiting climatic factors at different scales and their functional interactions at different ecological levels is critical to be able to predict reliably future population dynamics and support conservation planning in arid ecosystems. KW - behavioral adaptation KW - body condition KW - body growth rate KW - climate change KW - El Nino Southern Oscillation (ENSO) KW - Gehyra variegata KW - population dynamics KW - population size KW - survival KW - thermoregulation Y1 - 2018 U6 - https://doi.org/10.1002/ecm.1301 SN - 0012-9615 SN - 1557-7015 VL - 88 IS - 3 SP - 336 EP - 352 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Mielke, Jahel T1 - Signals for 2 degrees C BT - the influence of policies, market factors and civil society actions on investment decisions for green infrastructure JF - Journal of Sustainable Finance & Investment N2 - The targets of the Paris Agreement make it necessary to redirect finance flows towards sustainable, low-carbon infrastructures and technologies. Currently, the potential of institutional investors to help finance this transition is widely discussed. Thus, this paper takes a closer look at influence factors for green investment decisions of large European insurance companies. With a mix of qualitative and quantitative methods, the importance of policy, market and civil society signals is evaluated. In summary, respondents favor measures that promote green investment, such as feed-in tariffs or adjustments of capital charges for green assets, over ones that make carbon-intensive investments less attractive, such as the phase-out of fossil fuel subsidies or a carbon price. While investors currently see a low impact of the carbon price, they rank a substantial reform as an important signal for the future. Respondents also emphasize that policy signals have to be coherent and credible to coordinate expectations. KW - Green infrastructure investment KW - policy signals KW - green finance KW - climate change KW - institutional investors Y1 - 2019 U6 - https://doi.org/10.1080/20430795.2018.1528809 SN - 2043-0795 SN - 2043-0809 VL - 9 IS - 2 SP - 87 EP - 115 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Reibold, Kerstin T1 - Settler Colonialism, Decolonization, and Climate Change JF - Journal of applied philosophy N2 - The article proposes that climate change makes enduring colonial injustices and structures visible. It focuses on the imposition and dominance of colonial concepts of land and self-determination on Indigenous peoples in settler states. It argues that if the dominance of these colonial frameworks remains unaddressed, the progressing climate change will worsen other colonial injustices, too. Specifically, Indigenous self-determination capabilities will be increasingly undermined, and Indigenous peoples will experience the loss of what they understand as relevant land from within their own ontologies of land. The article holds that even if settler states strive to repair colonial injustices, these efforts will be unsuccessful if climate change occurs and decolonization is pursued within the framework of a settler colonial ontology of land. Therefore, the article suggests, decolonization of the ontologies of land and concepts of self-determination is a precondition for a just response to climate change. KW - territorial rights KW - indigenous rights KW - climate change KW - colonialism Y1 - 2022 U6 - https://doi.org/10.1111/japp.12573 SN - 0264-3758 SN - 1468-5930 PB - Wiley-Blackwell CY - Oxford ER - TY - THES A1 - Bittermann, Klaus T1 - Semi-empirical sea-level modelling T1 - Semiempirische Meeresspiegelmodellierung N2 - Semi-empirical sea-level models (SEMs) exploit physically motivated empirical relationships between global sea level and certain drivers, in the following global mean temperature. This model class evolved as a supplement to process-based models (Rahmstorf (2007)) which were unable to fully represent all relevant processes. They thus failed to capture past sea-level change (Rahmstorf et al. (2012)) and were thought likely to underestimate future sea-level rise. Semi-empirical models were found to be a fast and useful tool for exploring the uncertainties in future sea-level rise, consistently giving significantly higher projections than process-based models. In the following different aspects of semi-empirical sea-level modelling have been studied. Models were first validated using various data sets of global sea level and temperature. SEMs were then used on the glacier contribution to sea level, and to infer past global temperature from sea-level data via inverse modelling. Periods studied encompass the instrumental period, covered by tide gauges (starting 1700 CE (Common Era) in Amsterdam) and satellites (first launched in 1992 CE), the era from 1000 BCE (before CE) to present, and the full length of the Holocene (using proxy data). Accordingly different data, model formulations and implementations have been used. It could be shown in Bittermann et al. (2013) that SEMs correctly predict 20th century sea-level when calibrated with data until 1900 CE. SEMs also turned out to give better predictions than the Intergovernmental Panel on Climate Change (IPCC) 4th assessment report (AR4, IPCC (2007)) models, for the period from 1961–2003 CE. With the first multi-proxy reconstruction of global sea-level as input, estimate of the human-induced component of modern sea-level change and projections of future sea-level rise were calculated (Kopp et al. (2016)). It turned out with 90% confidence that more than 40 % of the observed 20th century sea-level rise is indeed anthropogenic. With the new semi-empirical and IPCC (2013) 5th assessment report (AR5) projections the gap between SEM and process-based model projections closes, giving higher credibility to both. Combining all scenarios, from strong mitigation to business as usual, a global sea-level rise of 28–131 cm relative to 2000 CE, is projected with 90% confidence. The decision for a low carbon pathway could halve the expected global sea-level rise by 2100 CE. Present day temperature and thus sea level are driven by the globally acting greenhouse-gas forcing. Unlike that, the Milankovich forcing, acting on Holocene timescales, results mainly in a northern-hemisphere temperature change. Therefore a semi-empirical model can be driven with northernhemisphere temperatures, which makes it possible to model the main subcomponent of sea-level change over this period. It showed that an additional positive constant rate of the order of the estimated Antarctic sea-level contribution is then required to explain the sea-level evolution over the Holocene. Thus the global sea level, following the climatic optimum, can be interpreted as the sum of a temperature induced sea-level drop and a positive long-term contribution, likely an ongoing response to deglaciation coming from Antarctica. N2 - Semiempirische Meeresspiegelmodelle (SEMe) nutzen die physikalisch motivierte, empirische Beziehung des globalen Meeresspiegels zu einem bestimmten Antrieb. Im Folgenden ist das die mittlere globale Temperatur. Diese Modellklasse entstand als Ergänzung zu prozeßbasierten Modellen, die nicht alle relevanten Prozesse abbilden konnten (Rahmstorf (2007)) und die deshalb weder den beobachteten Meeresspiegel erklären konnten (Rahmstorf et al. (2012)) noch vertrauenswürdige Zukunftsprojektionen lieferten. Semiempirische Modelle sind eine gute und schnelle Option, die Unsicherheit im zukünftigen Meeresspiegelanstieg auszuloten, wobei sie konsistent höhere Zukunftsprojektionen lieferten als prozeßbasierte Modelle. Im Folgenden wurden verschiedene Aspekte der semiempirischen Meeresspiegelmodellierung untersucht. Modelle wurden erst mit verschiedenen globalen Temperatur- und Meeresspiegeldatensätzen validiert. SEMe wurden dann auf den Meeresspiegelbeitrag von Gletschern angewandt und genutzt, um die globale Temperatur aus Meeresspiegeldaten abzuleiten. Die untersuchten Zeiträume variieren zwischen dem instrumentellen Abschnitt mit Pegelstandsmessungen (seit dem Jahr 1700 in Amsterdam) und Satellitendaten (seit 1992), dem Zeitraum seit 1000 vor Christus und dem gesamten Holozän (mittels Proxydaten). Entsprechend wurden verschiedene Daten, Modellformulierungen und -implementationen benutzt. Es konnte in Bittermann et al. (2013) gezeigt werden, dass SEMe den beobachteten Meeresspiegel des 20sten Jahrhunderts korrekt vorhersagen können, wenn sie bis zum Jahr 1900 kalibriert wurden. Auch für den Zeitraum 1961 bis 2003 lieferten SEMe bessere Vorhersagen als der vierte Sachstandsbericht des Intergovernmental Panel on Climate Change (AR4, IPCC (2007)). Mit der ersten globalen multi-proxy Rekonstruktion des globalen Meeresspiegels als Input konnten sowohl der anthropogene Anteil des modernen Meeresspiegelanstiegs als auch Zukunftsprojektionen berechnet werden (Kopp et al. (2016)). Es zeigt sich mit 90% Sicherheit, dass mehr als 40 % des beobachteten Meeresspiegelanstiegs im 20sten Jahrhundert anthropogenen Ursprungs sind. Mit den neuen semiempirischen Zukunftsprojektionen und denen des fünften Sachstandsberichtes (AR5) des IPCC (2013) läßt sich die Kluft zwischen SEMen und prozeßbasierten Modellen schließen, was beide vertrauenswürdiger macht. Über alle Szenarien hinweg, von starker Treibhausgaseinsparung bis zum ungebremsten Ausstoß, ergibt sich, mit 90% Sicherheit, zwischen 2000 und 2100 ein Meeresspiegelanstieg von 28 bis 131 cm. Die Entscheidung starker Treibhausgaseinsparungen kann den erwarteten globalen Meeresspiegelanstieg im Jahr 2100 halbieren. Die gegenwärtige globale Temperatur, und damit der globale Meeresspiegel, werden von dem global wirkenden Treibhausgasforcing bestimmt. Im Gegensatz dazu wirkt das orbitale Forcing, welches über Holozän-Zeitskalen dominiert, hauptsächlich auf die Nordhemisphäre. Deshalb kann man ein SEM mit Nordhemisphärentemperaturen antreiben und dadurch die Hauptkomponente der Meeresspiegeländerung über das Holozän simulieren. Es stellte sich heraus, dass eine zusätzliche konstante Rate, von der Größenordnung des antarktischen Beitrags zum Meeresspiegel, nötig ist, um den Meeresspiegelverlauf des Holozäns zu erklären. Der Meeresspiegel seit dem Holozän-Klimaoptimum kann also als eine Summe von temperaturbedingtem Fallen und einem langfristigen positiven Beitrag, wahrscheinlich einer andauernden Reaktion auf die Deglaziation der Antarktis, interpretiert werden. KW - sea level KW - Meeresspiegel KW - climate change KW - Klimawandel KW - projections KW - Projektionen KW - anthropogenic sea level KW - anthropogener Meeresspiegel KW - Holocene KW - Holozän KW - semi-empirical models KW - semiempirische Modelle Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-93881 ER - TY - THES A1 - Wulf, Hendrik T1 - Seasonal precipitation, river discharge, and sediment flux in the western Himalaya T1 - Saisonaler Niederschlag, Wasserabfluss und Sedimentationsfluss im westlichen Himalaya N2 - Rainfall, snow-, and glacial melt throughout the Himalaya control river discharge, which is vital for maintaining agriculture, drinking water and hydropower generation. However, the spatiotemporal contribution of these discharge components to Himalayan rivers is not well understood, mainly because of the scarcity of ground-based observations. Consequently, there is also little known about the triggers and sources of peak sediment flux events, which account for extensive hydropower reservoir filling and turbine abrasion. We therefore lack basic information on the distribution of water resources and controls of erosion processes. In this thesis, I employ various methods to assess and quantify general characteristics of and links between precipitation, river discharge, and sediment flux in the Sutlej Valley. First, I analyze daily precipitation data (1998-2007) from 80 weather stations in the western Himalaya, to decipher the distribution of rain- and snowfall. Rainfall magnitude frequency analyses indicate that 40% of the summer rainfall budget is attributed to monsoonal rainstorms, which show higher variability in the orogenic interior than in frontal regions. Combined analysis of rainstorms and sediment flux data of a major Sutlej River tributary indicate that monsoonal rainfall has a first order control on erosion processes in the orogenic interior, despite the dominance of snowfall in this region. Second, I examine the contribution of rainfall, snow and glacial melt to river discharge in the Sutlej Valley (s55,000 km2), based on a distributed hydrological model, which covers the period 2000-2008. To achieve high spatial and daily resolution despite limited ground-based observations the hydrological model is forced by daily remote sensing data, which I adjusted and calibrated with ground station data. The calibration shows that the Tropical Rainfall Measuring Mission (TRMM) 3B42 rainfall product systematically overestimates rainfall in semi-arid and arid regions, increasing with aridity. The model results indicate that snowmelt-derived discharge (74%) is most important during the pre-monsoon season (April to June) whereas rainfall (56%) and glacial melt (17%) dominate the monsoon season (July-September). Therefore, climate change most likely causes a reduction in river discharge during the pre-monsoon season, which especially affects the orogenic interior. Third, I investigate the controls on suspended sediment flux in different parts of the Sutlej catchments, based on daily gauging data from the past decade. In conjunction with meteorological data, earthquake records, and rock strength measurements I find that rainstorms are the most frequent trigger of high-discharge events with peaks in suspended sediment concentrations (SSC) that account for the bulk of the suspended sediment flux. The suspended sediment flux increases downstream, mainly due to increases in runoff. Pronounced erosion along the Himalayan Front occurs throughout the monsoon season, whereas efficient erosion of the orogenic interior is confined to single extreme events. The results of this thesis highlight the importance of snow and glacially derived melt waters in the western Himalaya, where extensive regions receive only limited amounts of monsoonal rainfall. These regions are therefore particularly susceptible to global warming with major implications on the hydrological cycle. However, the sediment discharge data show that infrequent monsoonal rainstorms that pass the orographic barrier of the Higher Himalaya are still the primary trigger of the highest-impact erosion events, despite being subordinate to snow and glacially–derived discharge. These findings may help to predict peak sediment flux events and could underpin the strategic development of preventative measures for hydropower infrastructures. N2 - Regen, Schnee- und Gletscherschmelze speisen die Flüsse des Himalajas, die eine große Bedeutung für die Landwirtschaft, Trinkwasserversorgung und Wasserkraftnutzung in Südasien aufweisen. Welchen Anteil die einzelnen Abflusskomponenten am Gesamtabfluss in Raum und Zeit besitzen, ist jedoch kaum quantifiziert, da es in der entlegenen Region an Bodenmessstationen mangelt. Aus diesem Grund ist auch wenig über die Auslöser und Herkunftsgebiete von hohen Sedimentaustragsereignissen bekannt, die im erheblichen Maße dazu beitragen, dass die Kapazität vonWasserkraftreservoiren abnimmt undWasserkraftturbinen abradieren. Daher fehlen bisher grundlegende Informationen zur räumlichen Verteilung von Wasserressourcen und zu den Ursachen von Erosionsprozessen. In dieser Arbeit benutze ich verschiedene Methoden um die Eigenschaften von und die Beziehungen zwischen Niederschlag, Abflussmenge und Sedimentaustrag im Sutlej-Tal zu untersuchen. In einer ersten Studie analysiere ich Tagesniederschläge (1998-2007) von 80 Wetterstationen aus dem westlichen Himalaja, um die räumliche Verteilung von Regen- und Schneeniederschlägen zu charakterisieren. Die weitere Analyse der Magnituden-Häufigkeitsverteilung von Regenfällen zeigt, dass 40% der sommerlichen Niederschläge auf monsunale Starkregenereignisse zurückgehen, die eine höhere Variabilität im Gebirgsinneren aufweisen als an der Gebirgsfront. Die Kombination von Niederschlagsdaten mit Sedimentaustragsdaten für einen der größten Zuflüsse des Sutlejs zeigt, dass monsunaler Niederschlag der primäre Auslöser von Erosionsprozessen im Gebirgsinneren ist, ungeachtet größerer Abflussmengen durch Schnee- und Gletscherschmelze. In einer zweiten Studie untersuche ich den Beitrag von Regen, Schnee- und Gletscherschmelze zur Abflussmenge im Sutlej-Tal (s55.000 km2) mit Hilfe eines hydrologischen Modells für den Jahreszeitraum 2000-2008. Um trotz der begrenzten Bodenmessungen eine hohe räumliche und zeitliche Auflösung zu erzielen, basiert das Modell auf täglichen Fernerkundungsdaten, die ich mit allen verfügbaren Bodenstationsdaten kalibriert und an diese angepasst habe. Die Kalibrierung zeigt, dass das Regenniederschlagsprodukt 3B42 der „Tropical Rainfall Measuring Mission“ (TRMM) den Bodenniederschlag in den semi-ariden bis ariden Gebirgsregionen mit zunehmender Trockenheit systematisch überschätzt. Die Modellierungsergebnisse verdeutlichen, dass die Schneeschmelze den bedeutendsten Beitrag zur Abflussmenge (74 %) zwischen April und Juni aufbringt, während Regen (56%) und Gletscherschmelze (17%) die Monsunsaison (Juli-September) prägen. Daher ist anzunehmen, dass der Klimawandel zu einer Verringerung der Abflussmenge zwischen April und Juni führen wird, was sich besonders auf das Gebirgsinnere auswirkt. In einer dritten Studie untersuche ich mit Hilfe von täglichen Messdaten der letzten Dekade die Ursachen und Eigenschaften des Sedimentaustrags in verschiedenen Bereichen des Sutlej-Einzugsgebietes. Auf der Grundlage von meteorologischen Daten, Erdbebenaufzeichnungen und Gesteinsfestigkeitsmessungen identifiziere ich Starkregenereignisse als häufigste Ursache für extreme Erosionsereignisse, die einen Großteil des gesamten Sedimentaustrags ausmachen. Großräumig betrachtet nimmt der Sedimentaustrag flussabwärts zu, was hauptsächlich auf den Anstieg der Abflussmenge zurückzuführen ist. Zur Monsunzeit treten Erosionsprozesse entlang der Himalajafront besonders häufig auf, während im Gebirgsinneren die Erosion auf einzelne Extremereignisse beschränkt ist. Die Ergebnisse dieser Arbeit untersteichen die Bedeutung von Schnee- und Gletscherschmelze im westlichen Himalaja, in dem große Gebiete nur vereinzelt von monsunalen Niederschlägen erreicht werden. Diese Gebiete sind daher besonders anfällig für den Klimawandel mit weitreichenden Konsequenzen für den Wasserhaushalt in der Region. Die Analyse von Sedimentaustragsdaten zeigt jedoch, dass vereinzelte monsunale Regenstürme, welche die topographische Barriere des Himalaja überqueren, die primäre Ursache von extremen Erosionsereignissen sind, trotz der größeren Abflussmengen von Schnee- und Gletscherschmelze im Gebirgsinneren. Diese Ergebnisse können dazu beitragen, große Erosionsereignisse vorherzusagen und vorbeugende Maßnahmen zum Schutz von Wasserkraftanlagen zu entwickeln. KW - Klimawandel KW - Erosion KW - Monsun KW - Regensturm KW - Suspendsionsfracht KW - climate change KW - erosion KW - monsoon KW - rainstorm KW - suspended sediment Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-57905 ER - TY - JOUR A1 - van Rees, Charles B. A1 - Waylen, Kerry A. A1 - Schmidt-Kloiber, Astrid A1 - Thackeray, Stephen J. A1 - Kalinkat, Gregor A1 - Martens, Koen A1 - Domisch, Sami A1 - Lillebo, Ana A1 - Hermoso, Virgilio A1 - Grossart, Hans-Peter A1 - Schinegger, Rafaela A1 - Decleer, Kris A1 - Adriaens, Tim A1 - Denys, Luc A1 - Jaric, Ivan A1 - Janse, Jan H. A1 - Monaghan, Michael T. A1 - De Wever, Aaike A1 - Geijzendorffer, Ilse A1 - Adamescu, Mihai C. A1 - Jähnig, Sonja C. T1 - Safeguarding freshwater life beyond 2020 BT - recommendations for the new global biodiversity framework from the European experience JF - Conservation letters N2 - Plans are currently being drafted for the next decade of action on biodiversity-both the post-2020 Global Biodiversity Framework of the Convention on Biological Diversity (CBD) and Biodiversity Strategy of the European Union (EU). Freshwater biodiversity is disproportionately threatened and underprioritized relative to the marine and terrestrial biota, despite supporting a richness of species and ecosystems with their own intrinsic value and providing multiple essential ecosystem services. Future policies and strategies must have a greater focus on the unique ecology of freshwater life and its multiple threats, and now is a critical time to reflect on how this may be achieved. We identify priority topics including environmental flows, water quality, invasive species, integrated water resources management, strategic conservation planning, and emerging technologies for freshwater ecosystem monitoring. We synthesize these topics with decades of first-hand experience and recent literature into 14 special recommendations for global freshwater biodiversity conservation based on the successes and setbacks of European policy, management, and research. Applying and following these recommendations will inform and enhance the ability of global and European post-2020 biodiversity agreements to halt and reverse the rapid global decline of freshwater biodiversity. KW - climate change KW - conservation KW - ecosystem services KW - rivers KW - sustainable KW - development goals KW - water resources KW - wetlands Y1 - 2020 U6 - https://doi.org/10.1111/conl.12771 SN - 1755-263X VL - 14 IS - 1 PB - Wiley CY - Hoboken ER - TY - THES A1 - Kornhuber, Kai T1 - Rossby wave dynamics and changes in summertime weather extremes T1 - Rossby Wellendynamik und Veränderungen von Extremwetter im Sommer N2 - Extreme weather events like heatwaves and floods severely affect societies with impacts ranging from economic damages to losses in human lifes. Global warming caused by anthropogenic greenhouse gas emissions is expected to increase their frequency and intensity, particularly in the warm season. Next to these thermodynamic changes, climate change might also impact the large scale atmospheric circulation.Such dynamic changes might additionally act on the occurence of extreme weather events, but involved mechanisms are often highly non-linear. Therefore, large uncertainty exists on the exact nature of these changes and the related risks to society. Particularly in the densely populated mid-latitudes weather patterns are governed by the large scale circulation like the jet-streams and storm tracks. Extreme weather in this region is often related to persistent weather systems associated with a strongly meandering jet-stream. Such meanders are called Rossby waves. Under specific conditions they can become slow moving, stretched around the entire hemisphere and generate simultaneaous heat- and rainfall extremes in far-away regions. This thesis aims at enhancing the understanding of synoptic-scale, circumglobal Rossby waves and the associated risks of dynamical changes to society. More specific, the analyses investigate their relation to extreme weather, regions at risk, under which conditions they are generated, and the influence of anthropogenic climate change on those conditions now, in the past and in the future. I find that circumglobal Rossby waves promoted simultaneous occuring weather extremes across the northern hemisphere in several recent summers. Further, I present evidence that they are often linked to quasiresonant-amplification of planetary waves. These events include the 2003 European heatwave and the Moscow heatwave of 2010. This non-linear mechanism acts on the upper level flow through trapping and amplification of stationary synoptic scale waves. I show that this resonance mechanism acts in both hemispheres and is related to extreme weather. A main finding is that circumglobal Rossby waves primarily occur as two specific teleconnection patterns associated with a wave 5 and wave 7 pattern in the northern hemisphere, likely due to the favourable longitudinal distance of prominent mountain ridges here. Furthermore, I identify those regions which are particularly at risk: The central United States, western Europe and the Ukraine/Russian region. Moreover, I present evidence that the wave 7 pattern has and extreme weather in these regions. My results suggest that the increase in frequency can be linked to favourable changes in large scale temperature gradients, which I show to be largely underestimated by model simulations. Using surface temperature fingerprint as proxy for investigating historic and future model ensembles, evidence is presented that anthropogenic warming has likely increased the probability for the occurence of circumglobal Rossby waves. Further it is shown that this might lead to a doubling of such events until the end of the century under a high-emission scenario. Overall, this thesis establishes several atmosphere-dynamical pathways by which changes in large scale temperature gradients might link to persistent boreal summer weather. It highlights the societal risks associated with the increasing occurence of a newly discovered Rossby wave teleconnection pattern, which has the potential to cause simultaneaous heat-extremes in the mid-latitudinal bread-basket regions. In addition, it provides further evidence that the traditional picture by which quasi-stationary Rossby waves occur only in the low wavenumber regime, should be reconsidered. N2 - Extreme Wetterereignisse haben oft katastrophale Folgen für Menschen und Umwelt. Die zuletzt beobachtete Zunahme von Hitzewellen und Überschwemmungen im Sommer lässt sich zum Teil mit dem Klimawandel, verursacht durch den Ausstoß von Treibhausgasen aus fossilen Brennstoffen, erkären. Allerdings übetrafen einige Extremereignisse der jüngeren Vergangenheit in ihrer Intensität, das was allein durch die Erwärmung im globalen Mittel zu erwarten wäre. Der Klimawandel wirkt sich ebenfalls auf die atmosphärische Zirkulation, wie beispielsweise den Jetstream aus. Es wird hier vermutet, dass Änderungen in der Dynamik Extrem-Ereignisse verstärken, indem sie beispielsweise langanhaltender werden. Allerdings sind die entsprechenden Mechanismen komplex und stark nicht-linear, was die Unsicherheiten in Bezug auf zuünftige Risiken vergrößert. Ein Mechanismus der mit extremen Wetter in den mittleren Breiten in Verbindung gebracht wurde, ist ein stark mäandernder Jet-Stream. Dieser führt zu ungewöhnlichen Temperaturen in den mittleren Breiten weile dies Mänder, genannt Rossby-Wellen, den Transport von ungewöhnlich warmer beziehungsweise kalter Luft entlang der Breiten erlauben. Unter bestimmten Bedingungen erstrecken sich diese Rossby Wellen über die gesamte Hemisphäre und führen zum synchronen auftreten von Wetterextremen entlang den mittleren Breiten. Extreme treten insbesondere dann auf wenn sie lang über bestimmten Regionen verharren. Diese Dissertation erforscht den Zusammenhang dieser quasi-stationären Rossby-Wellen und Wetter-Extremen: In welchem Maße können diese durch Rossby-Wellen erklärt werden, welche Regionen sind besonders betroffen und welchen Bedingungen sind für ihr Entstehen förderlich und wie wirkt sich der Klimawandel auf diese Bedingungen aus? Ich zeige, dass einige der verheerendsten Wetterextreme der jüngeren Vergangenheit durch hemisphärische Rossby-Wellenmuster erzeugt wurden und dass diese zumeist synchron mit anderen ungewöhnlichen Wettersituationen in den mittleren Breiten auftraten. Desweiteren zeige ich, dass einige dieser Ereignisse mit dem resonanten Aufschaukeln einiger Wellenkomponenten erklärt werden könnnen (engl. Quasi-resonant Amplification of Planetary Waves, kurz: QRA). Diesem nicht-linearen Mechanismus zufolge verhindert ein starker Jet, dass bestimmte Wellen ihre Energie in Richung Äquator oder Pol verlieren und so förmlich in den mittleren Breiten gefangen werden. Diese Wellen können dann resonant mit dem stationären thermischen und orographischen Störungen interagieren und gewinnen so an Intensität. Ich zeige, dass dieser Mechanismus sowohl in der Nord- als auch in der Südhemisphäre wirkt. Desweiteren zeige ich, dass die Rossby-Wellen in der Nordhemisphäre als zwei wiederkehrende örtlich festgelegte Wellenmuster, charakterisiert durch Welle 5 und Welle 7, auftreten. Dies erkläre ich mit dem relativen Abstand markanter Gebirgskämme entlang der Längengrade in den mittleren Breiten. Dieses Ergebnis ermöglicht es jene Regionen zu identifizieren, welche während solcher Ereignisse besonders gefährdet sind: das Zentrum der USA, Westeuropa und die Region Ukraine / Russland. Ich zeige, dass das Welle-7-Muster in den letzten Jahrzehnten in seiner Häufigkeit zugenommen hat, was die beobachtete Zunahme von extremen Wetter in diesen Regionen erklären könnte. Diese Zunahme führe ich auf die Veränderungen der groß-skaligen Temperaturgradienten entlang der Längen und Breitengrade zurück. Ich zeige zudem, dass diese Veränderungen durch Modelle weitestgehend unterschätzt werden. Über ein charakteristisches Temperaturprofil als Proxy untersuchen wir Modeldaten von historische und Projektionen. Diese Analyse zeigt, dass die anthropogene Erwärmung mit einiger Wahrscheinlichkeit die Bedingungen für die erzeugung solcher Rossby-Wellen verändert hat. Desweiteren kommt es unter der Annahme ungestoppter Emissionen vermutlich zu einer Verdopplung dieser Ereignisse führen zum Ende des Jahrhunderts. In dieser Dissertation zeige ich auf wie die Veränderung großskaliger Oberflächen-Temperatur-Gradienten mit dem vermehrten Aufkommen langanhaltender und oft extremen Wetterereignisse zusammenhängt. Ich indentifiziere die Regionen, die durch das Welle 7 Muster besonders gefärdet sind. Desweiteren, geben meine Ergebnisse weitere Hinweise darauf, dass die traditionell Sicht, aus der quasi-stationäre-Rossby-Wellen nur in Form von niedrigen Wellenzahlen vorkommen, überdacht werden muss. KW - Telekonnektionen KW - Atmosphärendynamik KW - Jetstream KW - Klimawandel KW - Hitzewellen KW - teleconnections KW - atmosphere dynamics KW - jet stream KW - climate change KW - heatwaves Y1 - 2017 ER - TY - THES A1 - Kemter, Matthias T1 - River floods in a changing world T1 - Flusshochwasser in einer sich ändernden Welt N2 - River floods are among the most devastating natural hazards worldwide. As their generation is highly dependent on climatic conditions, their magnitude and frequency are projected to be affected by future climate change. Therefore, it is crucial to study the ways in which a changing climate will, and already has, influenced flood generation, and thereby flood hazard. Additionally, it is important to understand how other human influences - specifically altered land cover - affect flood hazard at the catchment scale. The ways in which flood generation is influenced by climatic and land cover conditions differ substantially in different regions. The spatial variability of these effects needs to be taken into account by using consistent datasets across large scales as well as applying methods that can reflect this heterogeneity. Therefore, in the first study of this cumulative thesis a complex network approach is used to find 10 clusters of similar flood behavior among 4390 catchments in the conterminous United States. By using a consistent set of 31 hydro-climatological and land cover variables, and training a separate Random Forest model for each of the clusters, the regional controls on flood magnitude trends between 1960-2010 are detected. It is shown that changes in rainfall are the most important drivers of these trends, while they are regionally controlled by land cover conditions. While climate change is most commonly associated with flood magnitude trends, it has been shown to also influence flood timing. This can lead to trends in the size of the area across which floods occur simultaneously, the flood synchrony scale. The second study is an analysis of data from 3872 European streamflow gauges and shows that flood synchrony scales have increased in Western Europe and decreased in Eastern Europe. These changes are attributed to changes in flood generation, especially a decreasing relevance of snowmelt. Additionally, the analysis shows that both the absolute values and the trends of flood magnitudes and flood synchrony scales are positively correlated. If these trends persist in the future and are not accounted for, the combined increases of flood magnitudes and flood synchrony scales can exceed the capacities of disaster relief organizations and insurers. Hazard cascades are an additional way through which climate change can influence different aspects of flood hazard. The 2019/2020 wildfires in Australia, which were preceded by an unprecedented drought and extinguished by extreme rainfall that led to local flooding, present an opportunity to study the effects of multiple preceding hazards on flood hazard. All these hazards are individually affected by climate change, additionally complicating the interactions within the cascade. By estimating and analyzing the burn severity, rainfall magnitude, soil erosion and stream turbidity in differently affected tributaries of the Manning River catchment, the third study shows that even low magnitude floods can pose a substantial hazard within a cascade. This thesis shows that humanity is affecting flood hazard in multiple ways with spatially and temporarily varying consequences, many of which were previously neglected (e.g. flood synchrony scale, hazard cascades). To allow for informed decision making in risk management and climate change adaptation, it will be crucial to study these aspects across the globe and to project their trajectories into the future. The presented methods can depict the complex interactions of different flood drivers and their spatial variability, providing a basis for the assessment of future flood hazard changes. The role of land cover should be considered more in future flood risk modelling and management studies, while holistic, transferable frameworks for hazard cascade assessment will need to be designed. N2 - Flusshochwasser gehören zu den verheerendsten Naturkatastrophen weltweit. Ihre Entstehung hängt von klimatischen Bedingungen ab, weshalb vorhergesagt wird, dass sich ihre Magnituden und Häufigkeit durch den Klimawandel ändern werden. Daher ist es notwendig zu untersuchen, auf welche Art sich ein verändertes Klima - auch im Vergleich mit Effekten durch Landbedeckungsänderungen - auf Hochwasserentstehung und -gefahr auswirken könnte und das bereits getan hat. Diese kumulative Arbeit beleuchtet drei Teilaspekte dieses Themas. In der ersten Studie werden mittels maschinellen Lernens die wichtigsten Variablen entdeckt und untersucht, die die Änderungen von Hochwassermagnituden in 4390 Einzugsgebieten in den USA von 1960-2010 kontrolliert haben. Es wird gezeigt, dass Änderungen der Regenmengen der entscheidende Faktor waren, während Landnutzung regional von großer Bedeutung war. Die zweite Studie untersucht von 1960-2010 Änderungen in der Distanz innerhalb welcher Hochwasser in verschiedenen Flüssen gleichzeitig auftreten. Daten von 3872 europäischen Flusspegeln zeigen, dass sich die Fläche der gleichzeitigen Überflutung in Westeuropa vergrößert und in Osteuropa verkleinert hat, was auf abnehmende Relevanz der Schneeschmelze bei der Hochwasserentstehung zurückzuführen ist. Die dritte Studie behandelt die Auswirkungen kaskadierender Naturkatastrophen auf Hochwasser am Beispiel der australischen Waldbrände 2019/2020. Die Untersuchung der verschieden stark betroffenen Nebenflüsse des Manning River zeigt, dass in einer Naturgefahrenkaskade selbst gewöhnliche Hochwasser substantielle Auswirkungen haben können. Diese Arbeit zeigt, dass die Menschheit Hochwassergefahren auf verschiedene Arten und mit räumlich sowie zeitlich variablen Resultaten beeinflusst. Diese Aspekte müssen zukünftig global näher untersucht und ihre Entwicklung für die Zukunft modelliert werden, um fundierte Entscheidungen in Hochwasserschutz treffen zu können. Für Hochwassermagnituden und die Fläche gleichzeitiger Überflutung können hierfür die präsentierten Methoden adaptiert werden. KW - hydrology KW - climate change KW - flood KW - Hydrologie KW - Klimawandel KW - Hochwasser Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-558564 ER - TY - JOUR A1 - Kuhla, Kilian A1 - Willner, Sven N. A1 - Otto, Christian A1 - Geiger, Tobias A1 - Levermann, Anders T1 - Ripple resonance amplifies economic welfare loss from weather extremes JF - Environmental research letters : ERL / Institute of Physics N2 - The most complex but potentially most severe impacts of climate change are caused by extreme weather events. In a globally connected economy, damages can cause remote perturbations and cascading consequences-a ripple effect along supply chains. Here we show an economic ripple resonance that amplifies losses when consecutive or overlapping weather extremes and their repercussions interact. This amounts to an average amplification of 21% for climate-induced heat stress, river floods, and tropical cyclones. Modeling the temporal evolution of 1.8 million trade relations between >7000 regional economic sectors, we find that the regional responses to future extremes are strongly heterogeneous also in their resonance behavior. The induced effect on welfare varies between gains due to increased demand in some regions and losses due to demand or supply shortages in others. Within the current global supply network, the ripple resonance effect of extreme weather is strongest in high-income economies-an important effect to consider when evaluating past and future economic climate impacts. KW - consecutive disasters KW - economic ripple resonance KW - repercussion resonance KW - weather extremes KW - supply network KW - climate impacts KW - climate change Y1 - 2021 U6 - https://doi.org/10.1088/1748-9326/ac2932 SN - 1748-9326 VL - 16 IS - 11 PB - IOP Publ. Ltd. CY - Bristol ER - TY - GEN A1 - Köchy, Martin A1 - Mathaj, Martin A1 - Jeltsch, Florian A1 - Malkinson, Dan T1 - Resilience of stocking capacity to changing climate in arid to Mediterranean landscapes N2 - Small livestock is an important resource for rural human populations in dry climates. How strongly will climate change affect the capacity of the rangeland? We used hierarchical modelling to scale quantitatively the growth of shrubs and annual plants, the main food of sheep and goats, to the landscape extent in the eastern Mediterranean region. Without grazing, productivity increased in a sigmoid way with mean annual precipitation. Grazing reduced productivity more strongly the drier the landscape. At a point just under the stocking capacity of the vegetation, productivity declined precipitously with more intense grazing due to a lack of seed production of annuals. We repeated simulations with precipitation patterns projected by two contrasting IPCC scenarios. Compared to results based on historic patterns, productivity and stocking capacity did not differ in most cases. Thus, grazing intensity remains the stronger impact on landscape productivity in this dry region even in the future. N2 - Kleinvieh ist eine wichtige Lebensgrundlage für die Landbevölkerung in trockenen Regionen. Wie stark wird sich der Klimawandel auf die Tragfähigkeit der Weideflächen auswirken? Wir benutzten hierarchische Modellierung, um das Wachstum von Sträuchern und einjährigen Kräutern, das wichtigste Futter für Ziegen und Schafe, quantitativ auf die Fläche von Landschaften in der östlichen Mittelmeerregion zu dimensionieren. Die Produktivität ohne Beweidung stieg sigmoidal mit dem mittleren Jahresniederschlag. Je trockener die Landschaft, desto stärker verminderte Beweidung die Produktion. An einem Punkt knapp unter der Tragfähigkeit der Vegetation, sank die Produktion stark mit zunehmender Beweidung, weil die Samenproduktion der Kräuter zu gering war. Wir wiederholten die Simulationen mit Niederschlagsverteilungsmustern gemäß zweier gegensätzlicher IPCC-Szenarien. Zukünftige Produktivität und Tragfähigkeit unterschieden sich in den meisten Fällen nicht von Ergebnissen auf Grund von historischer Niederschlagsverteilung. Allerdings war die zukünftige Produktivität in trockenen Habitaten der semiariden und trocken-mediterranen Regionen niedriger. Somit hat auch in Zukunft die Besatzdichte die größere Auswirkung auf die Produktivität dieser trockenen Landschaft als das Klima. "This abstract is provided by the authors, and is for convenience of the users only. The author certifies that the translation faithfully represents the official version in the language of the journal, which is the published Abstract of record and is the only Abstract to be used for reference and citation." T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 066 KW - topography KW - spatially explicit model KW - climate change KW - Middle East KW - stocking capacity Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-18720 ER - TY - JOUR A1 - Kong, Xiangzhen A1 - Ghaffar, Salman A1 - Determann, Maria A1 - Friese, Kurt A1 - Jomaa, Seifeddine A1 - Mi, Chenxi A1 - Shatwell, Tom A1 - Rinke, Karsten A1 - Rode, Michael T1 - Reservoir water quality deterioration due to deforestation emphasizes the indirect effects of global change JF - Water research : a journal of the International Association on Water Quality (IAWQ) N2 - Deforestation is currently a widespread phenomenon and a growing environmental concern in the era of rapid climate change. In temperate regions, it is challenging to quantify the impacts of deforestation on the catchment dynamics and downstream aquatic ecosystems such as reservoirs and disentangle these from direct climate change impacts, let alone project future changes to inform management. Here, we tackled this issue by investigating a unique catchment-reservoir system with two reservoirs in distinct trophic states (meso- and eutrophic), both of which drain into the largest drinking water reservoir in Germany. Due to the prolonged droughts in 2015-2018, the catchment of the mesotrophic reservoir lost an unprecedented area of forest (exponential increase since 2015 and ca. 17.1% loss in 2020 alone). We coupled catchment nutrient exports (HYPE) and reservoir ecosystem dynamics (GOTM-WET) models using a process-based modeling approach. The coupled model was validated with datasets spanning periods of rapid deforestation, which makes our future projections highly robust. Results show that in a short-term time scale (by 2035), increasing nutrient flux from the catchment due to vast deforestation (80% loss) can turn the mesotrophic reservoir into a eutrophic state as its counterpart. Our results emphasize the more prominent impacts of deforestation than the direct impact of climate warming in impairment of water quality and ecological services to downstream aquatic ecosystems. Therefore, we propose to evaluate the impact of climate change on temperate reservoirs by incorporating a time scale-dependent context, highlighting the indirect impact of deforestation in the short-term scale. In the long-term scale (e.g. to 2100), a guiding hypothesis for future research may be that indirect effects (e.g., as mediated by catchment dynamics) are as important as the direct effects of climate warming on aquatic ecosystems. KW - deforestation KW - climate change KW - temperate regions KW - reservoir KW - eutrophication KW - process-based modeling Y1 - 2022 U6 - https://doi.org/10.1016/j.watres.2022.118721 SN - 0043-1354 SN - 1879-2448 VL - 221 PB - Elsevier Science CY - Amsterdam [u.a.] ER - TY - GEN A1 - Geiger, Tobias A1 - Frieler, Katja A1 - Levermann, Anders T1 - Reply to Comment on: High-income does not protect against hurricane losses (Environmental research letters. - 12 (2017)) T2 - Environmental research letters N2 - Recently a multitude of empirically derived damage models have been applied to project future tropical cyclone (TC) losses for the United States. In their study (Geiger et al 2016 Environ. Res. Lett. 11 084012) compared two approaches that differ in the scaling of losses with socio-economic drivers: the commonly-used approach resulting in a sub-linear scaling of historical TC losses with a nation's affected gross domestic product (GDP), and the disentangled approach that shows a sub-linear increase with affected population and a super-linear scaling of relative losses with per capita income. Statistics cannot determine which approach is preferable but since process understanding demands that there is a dependence of the loss on both GDP per capita and population, an approach that accounts for both separately is preferable to one which assumes a specific relation between the two dependencies. In the accompanying comment, Rybski et al argued that there is no rigorous evidence to reach the conclusion that high-income does not protect against hurricane losses. Here we affirm that our conclusion is drawn correctly and reply to further remarks raised in the comment, highlighting the adequateness of our approach but also the potential for future extension of our research. KW - climate change KW - tropical cyclones KW - damage KW - meteorological extremes KW - vulnerability Y1 - 2017 U6 - https://doi.org/10.1088/1748-9326/aa88d6 SN - 1748-9326 VL - 12 PB - IOP Publ. Ltd. CY - Bristol ER - TY - JOUR A1 - Tesselaar, Max A1 - Botzen, W. J. Wouter A1 - Haer, Toon A1 - Hudson, Paul A1 - Tiggeloven, Timothy A1 - Aerts, Jeroen C. J. H. T1 - Regional inequalities in flood insurance affordability and uptake under climate change JF - Sustainability N2 - Flood insurance coverage can enhance financial resilience of households to changing flood risk caused by climate change. However, income inequalities imply that not all households can afford flood insurance. The uptake of flood insurance in voluntary markets may decline when flood risk increases as a result of climate change. This increase in flood risk may cause substantially higher risk-based insurance premiums, reduce the willingness to purchase flood insurance, and worsen problems with the unaffordability of coverage for low-income households. A socio-economic tipping-point can occur when the functioning of a formal flood insurance system is hampered by diminishing demand for coverage. In this study, we examine whether such a tipping-point can occur in Europe for current flood insurance systems under different trends in future flood risk caused by climate and socio-economic change. This analysis gives insights into regional inequalities concerning the ability to continue to use flood insurance as an instrument to adapt to changing flood risk. For this study, we adapt the "Dynamic Integrated Flood and Insurance" (DIFI) model by integrating new flood risk simulations in the model that enable examining impacts from various scenarios of climate and socio-economic change on flood insurance premiums and consumer demand. Our results show rising unaffordability and declining demand for flood insurance across scenarios towards 2080. Under a high climate change scenario, simulations show the occurrence of a socio-economic tipping-point in several regions, where insurance uptake almost disappears. A tipping-point and related inequalities in the ability to use flood insurance as an adaptation instrument can be mitigated by introducing reforms of flood insurance arrangements. KW - climate change KW - flood risk management KW - insurance KW - socio-economic KW - tipping-point KW - adaptation KW - partial equilibrium modeling Y1 - 2020 U6 - https://doi.org/10.3390/su12208734 SN - 2071-1050 VL - 12 IS - 20 PB - MDPI CY - Basel ER -