@article{RodriguesRodriguesRaabeetal.2023,
  author    = {Rodrigues, Glauber Pontes and Rodrigues, {\´I}talo Sampaio and Raabe, Armin and Holstein, Peter and De Araujo, Jos{\`e} Carlos},
  title     = {Direct measurement of open-water evaporation},
  series = {Hydrological sciences journal},
  volume    = {68},
  journal   = {Hydrological sciences journal},
  number    = {3},
  publisher = {Taylor \& Francis},
  address   = {Abingdon, Oxon},
  issn      = {0262-6667},
  doi       = {10.1080/02626667.2022.2157278},
  pages     = {379 -- 394},
  year      = {2023},
  abstract  = {This study investigates the sensitivity and uncertainty of evaporation assessment in a tropical reservoir in northeastern Brazil. For this purpose, four approaches were used: Penman, a Dalton-modified equation, a pressure meter and a novel acoustic sensor. The main objective is to evaluate whether sensors can be employed to adequately assess lake evaporation. The sensors were installed in floating pans and the equations are based on variables collected from a raft. The wind-inducted waves in the reservoir often disturbed the measurements using both pressure (uncertainty of +/- 0.6 mm) and acoustic (uncertainty of +/- 0.1 mm) sensors, causing flaws and affecting continuous monitoring. The modified Dalton model, based on data collected with a floating station, estimated values over three-hour courses of evaporation similar to those measured by the pressure meter. These findings are important contributions to an accurate monitoring of water losses through evaporation and reservoir operation, particularly in dry regions.},
  language  = {en}
}
@article{TianQinZhangetal.2022,
  author    = {Tian, Fang and Qin, Wen and Zhang, Ran and Herzschuh, Ulrike and Ni, Jian and Zhang, Chengjun and Mischke, Steffen and Cao, Xianyong},
  title     = {Palynological evidence for the temporal stability of the plant community in the Yellow River Source Area over the last 7,400 years},
  series = {Vegetation history and archaeobotany},
  volume    = {31},
  journal   = {Vegetation history and archaeobotany},
  number    = {6},
  publisher = {Springer},
  address   = {New York},
  issn      = {0939-6314},
  doi       = {10.1007/s00334-022-00870-5},
  pages     = {549 -- 558},
  year      = {2022},
  abstract  = {The terrestrial ecosystem in the Yellow River Source Area (YRSA) is sensitive to climate change and human impacts, although past vegetation change and the degree of human disturbance are still largely unknown. A 170-cm-long sediment core covering the last 7,400 years was collected from Lake Xingxinghai (XXH) in the YRSA. Pollen, together with a series of other environmental proxies (including grain size, total organic carbon (TOC) and carbonate content), were analysed to explore past vegetation and environmental changes for the YRSA. Dominant and common pollen components-Cyperaceae, Poaceae, Artemisia, Chenopodiaceae and Asteraceae-are stable throughout the last 7,400 years. Slight vegetation change is inferred from an increasing trend of Cyperaceae and decreasing trend of Poaceae, suggesting that alpine steppe was replaced by alpine meadow at ca. 3.5 ka cal bp. The vegetation transformation indicates a generally wetter climate during the middle and late Holocene, which is supported by increased amounts of TOC and Pediastrum (representing high water-level) and is consistent with previous past climate records from the north-eastern Tibetan Plateau. Our results find no evidence of human impact on the regional vegetation surrounding XXH, hence we conclude the vegetation change likely reflects the regional climate signal.},
  language  = {en}
}
@phdthesis{Pfalz2024,
  author    = {Pfalz, Gregor},
  title     = {Advancing knowledge of Arctic lake system dynamics: A data-driven perspective on spatiotemporal patterns},
  doi       = {10.25932/publishup-63655},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-636554},
  school      = {Universit{\"a}t Potsdam},
  pages     = {xiii, 136},
  year      = {2024},
  abstract  = {Ecosystems play a pivotal role in addressing climate change but are also highly susceptible to drastic environmental changes. Investigating their historical dynamics can enhance our understanding of how they might respond to unprecedented future environmental shifts. With Arctic lakes currently under substantial pressure from climate change, lessons from the past can guide our understanding of potential disruptions to these lakes. However, individual lake systems are multifaceted and complex. Traditional isolated lake studies often fail to provide a global perspective because localized nuances—like individual lake parameters, catchment areas, and lake histories—can overshadow broader conclusions. In light of these complexities, a more nuanced approach is essential to analyze lake systems in a global context. A key to addressing this challenge lies in the data-driven analysis of sedimentological records from various northern lake systems. This dissertation emphasizes lake systems in the northern Eurasian region, particularly in Russia (n=59). For this doctoral thesis, we collected sedimentological data from various sources, which required a standardized framework for further analysis. Therefore, we designed a conceptual model for integrating and standardizing heterogeneous multi-proxy data into a relational database management system (PostgreSQL). Creating a database from the collected data enabled comparative numerical analyses between spatially separated lakes as well as between different proxies. When analyzing numerous lakes, establishing a common frame of reference was crucial. We achieved this by converting proxy values from depth dependency to age dependency. This required consistent age calculations across all lakes and proxies using one age-depth modeling software. Recognizing the broader implications and potential pitfalls of this, we developed the LANDO approach ("Linked Age and Depth Modelling"). LANDO is an innovative integration of multiple age-depth modeling software into a singular, cohesive platform (Jupyter Notebook). Beyond its ability to aggregate data from five renowned age-depth modeling software, LANDO uniquely empowers users to filter out implausible model outcomes using robust geoscientific data. Our method is not only novel but also significantly enhances the accuracy and reliability of lake analyses. Considering the preceding steps, this doctoral thesis further examines the relationship between carbon in sediments and temperature over the last 21,000 years. Initially, we hypothesized a positive correlation between carbon accumulation in lakes and modelled paleotemperature. Our homogenized dataset from heterogeneous lakes confirmed this association, even if the highest temperatures throughout our observation period do not correlate with the highest carbon values. We assume that rapid warming events contribute more to high accumulation, while sustained warming leads to carbon outgassing. Considering the current high concentration of carbon in the atmosphere and rising temperatures, ongoing climate change could cause northern lake systems to contribute to a further increase in atmospheric carbon (positive feedback loop). While our findings underscore the reliability of both our standardized data and the LANDO method, expanding our dataset might offer even greater assurance in our conclusions.},
  language  = {en}
}
@article{WalchSinghSoreideetal.2022,
  author    = {Walch, Daniela M. R. and Singh, Rakesh K. and Soreide, Janne E. and Lantuit, Hugues and Poste, Amanda},
  title     = {Spatio-temporal variability of suspended particulate matter in a high-arctic estuary (Adventfjorden, Svalbard) using sentinel-2 time-series},
  series = {Remote sensing},
  volume    = {14},
  journal   = {Remote sensing},
  number    = {13},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2072-4292},
  doi       = {10.3390/rs14133123},
  pages     = {22},
  year      = {2022},
  abstract  = {Arctic coasts, which feature land-ocean transport of freshwater, sediments, and other terrestrial material, are impacted by climate change, including increased temperatures, melting glaciers, changes in precipitation and runoff. These trends are assumed to affect productivity in fjordic estuaries. However, the spatial extent and temporal variation of the freshwater-driven darkening of fjords remain unresolved. The present study illustrates the spatio-temporal variability of suspended particulate matter (SPM) in the Adventfjorden estuary, Svalbard, using in-situ field campaigns and ocean colour remote sensing (OCRS) via high-resolution Sentinel-2 imagery. To compute SPM concentration (C-SPMsat), a semi-analytical algorithm was regionally calibrated using local in-situ data, which improved the accuracy of satellite-derived SPM concentration by similar to 20\% (MRD). Analysis of SPM concentration for two consecutive years (2019, 2020) revealed strong seasonality of SPM in Adventfjorden. Highest estimated SPM concentrations and river plume extent (\% of fjord with C-SPMsat > 30 mg L-1) occurred during June, July, and August. Concurrently, we observed a strong relationship between river plume extent and average air temperature over the 24 h prior to the observation (R-2 = 0.69). Considering predicted changes to environmental conditions in the Arctic region, this study highlights the importance of the rapidly changing environmental parameters and the significance of remote sensing in analysing fluxes in light attenuating particles, especially in the coastal Arctic Ocean.},
  language  = {en}
}
@article{VehLuetzowKharlamovaetal.2022,
  author    = {Veh, Georg and L{\"u}tzow, Natalie and Kharlamova, Varvara and Petrakov, Dmitry and Hugonnet, Romain and Korup, Oliver},
  title     = {Trends, breaks, and biases in the frequency of reported glacier lake outburst floods},
  series = {Earth's future},
  volume    = {10},
  journal   = {Earth's future},
  number    = {3},
  publisher = {American Geophysical Union},
  address   = {Washington},
  issn      = {2328-4277},
  doi       = {10.1029/2021EF002426},
  pages     = {14},
  year      = {2022},
  abstract  = {Thousands of glacier lakes have been forming behind natural dams in high mountains following glacier retreat since the early 20th century. Some of these lakes abruptly released pulses of water and sediment with disastrous downstream consequences. Yet it remains unclear whether the reported rise of these glacier lake outburst floods (GLOFs) has been fueled by a warming atmosphere and enhanced meltwater production, or simply a growing research effort. Here we estimate trends and biases in GLOF reporting based on the largest global catalog of 1,997 dated glacier-related floods in six major mountain ranges from 1901 to 2017. We find that the positive trend in the number of reported GLOFs has decayed distinctly after a break in the 1970s, coinciding with independently detected trend changes in annual air temperatures and in the annual number of field-based glacier surveys (a proxy of scientific reporting). We observe that GLOF reports and glacier surveys decelerated, while temperature rise accelerated in the past five decades. Enhanced warming alone can thus hardly explain the annual number of reported GLOFs, suggesting that temperature-driven glacier lake formation, growth, and failure are weakly coupled, or that outbursts have been overlooked. Indeed, our analysis emphasizes a distinct geographic and temporal bias in GLOF reporting, and we project that between two to four out of five GLOFs on average might have gone unnoticed in the early to mid-20th century. We recommend that such biases should be considered, or better corrected for, when attributing the frequency of reported GLOFs to atmospheric warming.},
  language  = {en}
}
@article{AndreevRaschkeBiskabornetal.2021,
  author    = {Andreev, Andrei and Raschke, Elena and Biskaborn, Boris and Vyse, Stuart Andrew and Courtin, J{\´e}r{\´e}my and B{\"o}hmer, Thomas and Stoof-Leichsenring, Kathleen R. and Kruse, Stefan and Pestryakova, Luidmila Agafyevna and Herzschuh, Ulrike},
  title     = {Late Pleistocene to Holocene vegetation and climate changes in northwestern Chukotka (Far East Russia) deduced from lakes Ilirney and Rauchuagytgyn pollen records},
  series = {Boreas : an international journal of quaternary research},
  volume    = {50},
  journal   = {Boreas : an international journal of quaternary research},
  number    = {3},
  publisher = {Wiley-Blackwell},
  address   = {Oxford [u.a.]},
  issn      = {0300-9483},
  doi       = {10.1111/bor.12521},
  pages     = {652 -- 670},
  year      = {2021},
  abstract  = {This paper presents two new pollen records and quantitative climate reconstructions from northern Chukotka documenting environmental changes over the last 27.9 ka. Open tundra- and steppe-like habitats dominated between 27.9 and 18.7 cal. ka BP. Betula and Alnus shrubs might have grown in sheltered microhabitats but disappeared after 18.7 cal. ka BP. Although the climate was rather harsh, local herb-dominated communities supported herbivores as is evident by the presence of coprophilous spores in the sediments. The increase in Salix and Cyperaceae similar to 16.1 cal. ka BP suggests climate amelioration. Shrub Betula appeared similar to 15.9 cal. ka BP, and became dominant after similar to 15.52 cal. ka BP, whilst typical steppe communities drastically reduced. Very high presence of Botryococcus in the Lateglacial sediments reflects widespread shallow habitats, probably due to lake level increase. Shrub Alnus became common after similar to 13 cal. ka BP reflecting further climate amelioration. Simultaneously, herb communities gradually decreased in the vegetation reaching a minimum similar to 11.8 cal. ka BP. A gradual decrease of algae remains suggests a reduction of shallow-water habitats. Shrubby and graminoid tundra was dominant similar to 11.8-11.1 cal. ka BP, later Salix stands significantly decreased. The forest-tundra ecotone established in the Early Holocene, shortly after 11.1 cal. ka BP. Low contents of green algae in the Early Holocene sediments likely reflect deeper aquatic conditions. The most favourable climate conditions were between similar to 10.6 and 7 cal. ka BP. Vegetation became similar to the modern after similar to 7 cal. ka BP but Pinus pumila came to the Ilirney area at about 1.2 cal. ka BP. It is important to emphasize that the study area provided refugia for Betula and Alnus during MIS 2. It is also notable that our records do not reflect evidence of Younger Dryas cooling, which is inconsistent with some regional environmental records but in good accordance with some others.},
  language  = {en}
}
@article{ZhangCaoXuetal.2022,
  author    = {Zhang, Naimeng and Cao, Xianyong and Xu, Qinghai and Huang, Xiaozhong and Herzschuh, Ulrike and Shen, Zhongwei and Peng, Wei and Liu, Sisi and Wu, Duo and Wang, Jian and Xia, Huan and Zhang, Dongju and Chen, Fahu},
  title     = {Vegetation change and human-environment interactions in the Qinghai Lake Basin, northeastern Tibetan Plateau, since the last deglaciation},
  series = {Catena},
  volume    = {210},
  journal   = {Catena},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0341-8162},
  doi       = {10.1016/j.catena.2021.105892},
  pages     = {14},
  year      = {2022},
  abstract  = {The nature of the interaction between prehistoric humans and their environment, especially the vegetation, has long been of interest. The Qinghai Lake Basin in North China is well-suited to exploring the interactions between prehistoric humans and vegetation in the Tibetan Plateau, because of the comparatively dense distribution of archaeological sites and the ecologically fragile environment. Previous pollen studies of Qinghai Lake have enabled a detailed reconstruction of the regional vegetation, but they have provided relatively little information on vegetation change within the Qinghai Lake watershed. To address the issue we conducted a pollen-based vegetation reconstruction for an archaeological site (YWY), located on the southern shore of Qinghai Lake. We used high temporal-resolution pollen records from the YWY site and from Qinghai Lake, spanning the interval since the last deglaciation (15.3 kyr BP to the present) to quantitatively reconstruct changes in the local and regional vegetation using Landscape Reconstruction Algorithm models. The results show that, since the late glacial, spruce forest grew at high altitudes in the surrounding mountains, while the lakeshore environment was occupied mainly by shrub-steppe. From the lateglacial to the middle Holocene, coniferous woodland began to expand downslope and reached the YWY site at 7.1 kyr BP. The living environment of the local small groups of Paleolithic-Epipaleolithic humans (during 15.3-13.1 kyr BP and 9-6.4 kyr BP) changed from shrub-steppe to coniferous forest-steppe. The pollen record shows no evidence of pronounced changes in the vegetation community corresponding to human activity. However, based on a comparison of the local and regional vegetation reconstructions, low values of biodiversity and a significant increase in two indicators of vegetation degradation, Chenopodiaceae and Rosaceae, suggest that prehistoric hunters-gatherers likely disturbed the local vegetation during 9.0-6.4 kyr BP. Our findings are a preliminary attempt to study human-environment interactions at Paleolithic-Epipaleolithic sites in the region, and they contribute to ongoing environmental archaeology research in the Tibetan Plateau.},
  language  = {en}
}
@article{DietzeBellOeztuerketal.2022,
  author    = {Dietze, Michael and Bell, Rainer and {\"O}zt{\"u}rk, Ugur and Cook, Kristen L. and Andermann, Christoff and Beer, Alexander R. and Damm, Bodo and Lucia, Ana and Fauer, Felix S. and Nissen, Katrin M. and Sieg, Tobias and Thieken, Annegret H.},
  title     = {More than heavy rain turning into fast-flowing water - a landscape perspective on the 2021 Eifel floods},
  series = {Natural hazards and earth system sciences},
  volume    = {22},
  journal   = {Natural hazards and earth system sciences},
  number    = {6},
  publisher = {Copernicus},
  address   = {G{\"o}ttingen},
  issn      = {1561-8633},
  doi       = {10.5194/nhess-22-1845-2022},
  pages     = {1845 -- 1856},
  year      = {2022},
  abstract  = {Rapidly evolving floods are rare but powerful drivers of landscape reorganisation that have severe and long-lasting impacts on both the functions of a landscape's subsystems and the affected society. The July 2021 flood that particularly hit several river catchments of the Eifel region in western Germany and Belgium was a drastic example. While media and scientists highlighted the meteorological and hydrological aspects of this flood, it was not just the rising water levels in the main valleys that posed a hazard, caused damage, and drove environmental reorganisation. Instead, the concurrent coupling of landscape elements and the wood, sediment, and debris carried by the fast-flowing water made this flood so devastating and difficult to predict. Because more intense floods are able to interact with more landscape components, they at times reveal rare non-linear feedbacks, which may be hidden during smaller events due to their high thresholds of initiation. Here, we briefly review the boundary conditions of the 14-15 July 2021 flood and discuss the emerging features that made this event different from previous floods. We identify hillslope processes, aspects of debris mobilisation, the legacy of sustained human land use, and emerging process connections and feedbacks as critical non-hydrological dimensions of the flood. With this landscape scale perspective, we develop requirements for improved future event anticipation, mitigation, and fundamental system understanding.},
  language  = {en}
}
@article{YadavSenMaoetal.2022,
  author    = {Yadav, Anshul and Sen, Sumit and Mao, Luca and Schwanghart, Wolfgang},
  title     = {Evaluation of flow resistance equations for high gradient rivers using geometric standard deviation of bed material},
  series = {Journal of hydrology},
  volume    = {605},
  journal   = {Journal of hydrology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0022-1694},
  doi       = {10.1016/j.jhydrol.2021.127292},
  pages     = {16},
  year      = {2022},
  abstract  = {A dataset of 2184 field measurements reported in the literature was used to evaluate the predictive capability of eight conventional flow resistance equations to predict the mean flow velocity in gravel-bed rivers. The results reveal considerable disagreement with the observed flow velocities for relative submergence less than 4 and for the non-uniformity of the bed material greater than 7.5 for all the equations. However, the predictions made using the Smart and Jaggi (1983), Ferguson (2007), and Rickenmann and Recking (2011) equations were closer to the observed values. Furthermore, bedload sediment transport also reduces the predictive capability of the equations considered in this study except for the Recking et al. (2008) equation, which was developed consid- ering active bedload transport. The performance of flow resistance equations improves when corrected by considering the geometric standard deviation of the bed material. Here we present an empirical approach using the whole dataset and its subsets for accounting for the additional energy losses occurring due to the wake vortices, spill losses, and free surface instabilities occurring due to the protrusions from the bed. The results obtained using the validation dataset shows the importance and usefulness of this approach to account for the additional energy losses, especially for the Strickler (1923) and Keulegan (1938) equations.},
  language  = {en}
}
@article{AndreevNazarovaLenzetal.2022,
  author    = {Andreev, Andrei and Nazarova, Larisa B. and Lenz, Marlene M. and B{\"o}hmer, Thomas and Syrykh, Ludmila and Wagner, Bernd and Melles, Martin and Pestryakova, Luidmila A. and Herzschuh, Ulrike},
  title     = {Late Quaternary paleoenvironmental reconstructions from sediments of Lake Emanda (Verkhoyansk Mountains, East Siberia)},
  series = {Journal of quaternary science : JQS},
  volume    = {37},
  journal   = {Journal of quaternary science : JQS},
  number    = {5},
  publisher = {Wiley},
  address   = {New York, NY [u.a.]},
  issn      = {0267-8179},
  doi       = {10.1002/jqs.3419},
  pages     = {884 -- 899},
  year      = {2022},
  abstract  = {Continuous pollen and chironomid records from Lake Emanda (65 degrees 17'N, 135 degrees 45'E) provide new insights into the Late Quaternary environmental history of the Yana Highlands (Yakutia). Larch forest with shrubs (alders, pines, birches) dominated during the deposition of the lowermost sediments suggesting its Early Weichselian [Marine Isotope Stage (MIS) 5] age. Pollen- and chironomid-based climate reconstructions suggest July temperatures (T-July) slightly lower than modern. Gradually increasing amounts of herb pollen and cold stenotherm chironomid head capsules reflect cooler and drier environments, probably during the termination of MIS 5. T-July dropped to 8 degrees C. Mostly treeless vegetation is reconstructed during MIS 3. Tundra and steppe communities dominated during MIS 2. Shrubs became common after similar to 14.5 ka BP but herb-dominated habitats remained until the onset of the Holocene. Larch forests with shrub alder and dwarf birch dominated after the Holocene onset, ca. 11.7 ka BP. Decreasing amounts of shrub pollen during the Lateglacial are assigned to the Older Dryas and Younger Dryas with T-July similar to 7.5 degrees C. T-July increased up to 13 degrees C. Shrub stone pine was present after similar to 7.5 ka BP. The vegetation has been similar to modern since ca. 5.8 ka BP. Chironomid diversity and concentration in the sediments increased towards the present day, indicating the development of richer hydrobiological communities in response to the Holocene thermal maximum.},
  language  = {en}
}