TY - THES A1 - Schönefeld, Romina T1 - Produktivität und Akzeptanz von Wortbildungsmustern bei Neologismen der 2000er Jahre N2 - Das Ziel der vorliegenden Masterarbeit ist es, die Interaktion zwischen der Produktivität und der Akzeptanz von Wortbildungsmustern sowie ihre mögliche Lexikalisierung zu zeigen. Es soll geklärt werden, wie die Produktivität von Wortbildungsmustern die Akzeptanz von Neologismen beeinflusst und inwiefern die Produktivität der gebildeten Neuwörter zu ihrer Lexikalisierung beiträgt. Dazu wurden in den 2000er Jahren im Deutschen aufgekommene Neologismen der Bereiche Bildung & Gesellschaft, Politik, Technik sowie Wirtschaft untersucht. Es wurde angenommen, dass ein neu gebildetes Wort durch die Sprecher eher akzeptiert wird, wenn dieses modellgerecht gebildet wurde. Dies befördert wiederum die Lexikalisierung, d. h. die Aufnahme des Neologismus in den Allgemeinwortschatz. Es konnte gezeigt werden, dass die betrachteten Neologismen vorwiegend nach produktiven und regulären Mustern gebildet wurden. Die Ergebnisse konnten die Annahmen folglich bestätigen: Neue Wortbildungen bzw. deren Etablierung und mögliche Lexikalisierung sowie ihre Akzeptanz hängen von der Produktivität ihrer Struktur ab. Weiterführende Forschung könnte sich mit Aspekten des Verstehensaufwands sowie mit Verarbeitungsstrategien bei der Lexikalisierung von Neologismen beschäftigen. N2 - The current paper is supposed to reveal the interaction between productivity and acceptability of word formation patterns as well as the lexicalization of them. It shall be clarified how the productivity affects the acceptability of neologisms and to what extent the productivity of the newly formed words contributes to their lexicalization. Therefore, neologisms which are emerged in the 2000s in German were explored, selected from the fields education & society (Bildung & Gesellschaft), politics (Politik), technology (Technik) and economy (Wirtschaft). The main assumption is that a newly formed word is more likely to be accepted if it would be formed modell-compliant. This in turn promotes lexicalization, i. e. this promotes the neologism‘s inclusion to the lexicon. It could be shown that the considered neologisms were mainly formed by productive and regular patterns. The results therefore confirm the assumptions: new word forms respectively their establishment and possible lexicalization as well as their acceptability depend on the productivity of their structure. Further research could consider aspects of cognitive effort or strategies of processing in lexicalization of neologisms. KW - Neologismus KW - Wortbildung KW - Produktivität KW - Akzeptanz KW - Lexikalisierung KW - neologism KW - word formation KW - productivity KW - acceptability KW - lexicalization Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-436853 ER - TY - JOUR A1 - Kayler, Zachary E. A1 - Premke, Katrin A1 - Gessler, Arthur A1 - Gessner, Mark O. A1 - Griebler, Christian A1 - Hilt, Sabine A1 - Klemedtsson, Leif A1 - Kuzyakov, Yakov A1 - Reichstein, Markus A1 - Siemens, Jan A1 - Totsche, Kai-Uwe A1 - Tranvik, Lars A1 - Wagner, Annekatrin A1 - Weitere, Markus A1 - Grossart, Hans-Peter T1 - Integrating Aquatic and Terrestrial Perspectives to Improve Insights Into Organic Matter Cycling at the Landscape Scale JF - Frontiers in Earth Science N2 - Across a landscape, aquatic-terrestrial interfaces within and between ecosystems are hotspots of organic matter (OM) mineralization. These interfaces are characterized by sharp spatio-temporal changes in environmental conditions, which affect OM properties and thus control OM mineralization and other transformation processes. Consequently, the extent of OM movement at and across aquatic-terrestrial interfaces is crucial in determining OM turnover and carbon (C) cycling at the landscape scale. Here, we propose expanding current concepts in aquatic and terrestrial ecosystem sciences to comprehensively evaluate OM turnover at the landscape scale. We focus on three main concepts toward explaining OM turnover at the landscape scale: the landscape spatiotemporal context, OM turnover described by priming and ecological stoichiometry, and anthropogenic effects as a disruptor of natural OM transfer magnitudes and pathways. A conceptual framework is introduced that allows for discussing the disparities in spatial and temporal scales of OM transfer, changes in environmental conditions, ecosystem connectivity, and microbial-substrate interactions. The potential relevance of priming effects in both terrestrial and aquatic systems is addressed. For terrestrial systems, we hypothesize that the interplay between the influx of OM, its corresponding elemental composition, and the elemental demand of the microbial communities may alleviate spatial and metabolic thresholds. In comparison, substrate level OM dynamics may be substantially different in aquatic systems due to matrix effects that accentuate the role of abiotic conditions, substrate quality, and microbial community dynamics. We highlight the disproportionate impact anthropogenic activities can have on OM cycling across the landscape. This includes reversing natural OM flows through the landscape, disrupting ecosystem connectivity, and nutrient additions that cascade across the landscape. This knowledge is crucial for a better understanding of OM cycling in a landscape context, in particular since terrestrial and aquatic compartments may respond differently to the ongoing changes in climate, land use, and other anthropogenic interferences. KW - landscape connectivity KW - organic matter mineralization KW - priming effects KW - ecological stoichiometry KW - aquatic-terrestrial interfaces KW - anthropogenic interferences Y1 - 2019 U6 - https://doi.org/10.3389/feart.2019.00127 SN - 2296-6463 VL - 7 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Lundgreen, Regitze B. C. A1 - Jaspers, Cornelia A1 - Traving, Sachia J. A1 - Ayala, Daniel J. A1 - Lombard, Fabien A1 - Grossart, Hans-Peter A1 - Nielsen, Torkel G. A1 - Munk, Peter A1 - Riemann, Lasse T1 - Eukaryotic and cyanobacterial communities associated with marine snow particles in the oligotrophic Sargasso Sea JF - Scientific reports N2 - Marine snow aggregates represent heterogeneous agglomerates of dead and living organic matter. Composition is decisive for their sinking rates, and thereby for carbon flux to the deep sea. For oligotrophic oceans, information on aggregate composition is particularly sparse. To address this, the taxonomic composition of aggregates collected from the subtropical and oligotrophic Sargasso Sea (Atlantic Ocean) was characterized by 16S and 18S rRNA gene sequencing. Taxonomy assignment was aided by a collection of the contemporary plankton community consisting of 75 morphologically and genetically identified plankton specimens. The diverse rRNA gene reads of marine snow aggregates, not considering Trichodesmium puffs, were dominated by copepods (52%), cnidarians (21%), radiolarians (11%), and alveolates (8%), with sporadic contributions by cyanobacteria, suggesting a different aggregate composition than in eutrophic regions. Composition linked significantly with sampling location but not to any measured environmental parameters or plankton biomass composition. Nevertheless, indicator and network analyses identified key roles of a few rare taxa. This points to complex regulation of aggregate composition, conceivably affected by the environment and plankton characteristics. The extent to which this has implications for particle densities, and consequently for sinking rates and carbon sequestration in oligotrophic waters, needs further interrogation. Y1 - 2019 U6 - https://doi.org/10.1038/s41598-019-45146-7 SN - 2045-2322 VL - 9 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Masigol, Hossein A1 - Khodaparast, Seyed Akbar A1 - Woodhouse, Jason Nicholas A1 - Rojas Jiménez, Keilor A1 - Fonvielle, Jeremy Andre A1 - Rezakhani, Forough A1 - Mostowfizadeh-Ghalamfarsa, Reza A1 - Neubauer, Darshan A1 - Goldhammer, Tobias A1 - Grossart, Hans-Peter T1 - The contrasting roles of aquatic fungi and oomycetes in the degradation and transformation of polymeric organic matter JF - Limnology and oceanography N2 - Studies on the ecological role of fungi and, to a lesser extent, oomycetes, are receiving increasing attention, mainly due to their participation in the cycling of organic matter in aquatic ecosystems. To unravel their importance in humification processes, we isolated several strains of fungi and oomycetes from Anzali lagoon, Iran. We then performed taxonomic characterization by morphological and molecular methods, analyzed the ability to degrade several polymeric substrates, performed metabolic fingerprinting with Ecoplates, and determined the degradation of humic substances (HS) using liquid chromatography-organic carbon detection. Our analyses highlighted the capacity of aquatic fungi to better degrade a plethora of organic molecules, including complex polymers. Specifically, we were able to demonstrate not only the utilization of these complex polymers, but also the role of fungi in the production of HS. In contrast, oomycetes, despite some morphological and physiological similarities with aquatic fungi, exhibited a propensity toward opportunism, quickly benefitting from the availability of small organic molecules, while exhibiting sensitivity toward more complex polymers. Despite their contrasting roles, our study highlights the importance of both oomycetes and fungi in aquatic organic matter transformation and cycling with potential implications for the global carbon cycle. Y1 - 2019 SN - 0024-3590 SN - 1939-5590 VL - 64 IS - 6 SP - 2662 EP - 2678 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Numberger, Daniela A1 - Ganzert, Lars A1 - Zoccarato, Luca A1 - Mühldorfer, Kristin A1 - Sauer, Sascha A1 - Grossart, Hans-Peter A1 - Greenwood, Alex D. T1 - Characterization of bacterial communities in wastewater with enhanced taxonomic resolution by full-length 16S rRNA sequencing JF - Scientific reports N2 - Wastewater treatment is crucial to environmental hygiene in urban environments. However, wastewater treatment plants (WWTPs) collect chemicals, organic matter, and microorganisms including pathogens and multi-resistant bacteria from various sources which may be potentially released into the environment via WWTP effluent. To better understand microbial dynamics in WWTPs, we characterized and compared the bacterial community of the inflow and effluent of a WWTP in Berlin, Germany using full-length 16S rRNA gene sequences, which allowed for species level determination in many cases and generally resolved bacterial taxa. Significantly distinct bacterial communities were identified in the wastewater inflow and effluent samples. Dominant operational taxonomic units (OTUs) varied both temporally and spatially. Disease associated bacterial groups were efficiently reduced in their relative abundance from the effluent by the WWTP treatment process, except for Legionella and Leptospira species which demonstrated an increase in relative proportion from inflow to effluent. This indicates that WWTPs, while effective against enteric bacteria, may enrich and release other potentially pathogenic bacteria into the environment. The taxonomic resolution of full-length 16S rRNA genes allows for improved characterization of potential pathogenic taxa and other harmful bacteria which is required to reliably assess health risk. Y1 - 2019 U6 - https://doi.org/10.1038/s41598-019-46015-z SN - 2045-2322 VL - 9 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Numberger, Daniela A1 - Dreier, Carole A1 - Vullioud, Colin A1 - Gabriel, Gülsah A1 - Greenwood, Alex D. A1 - Grossart, Hans-Peter T1 - Recovery of influenza a viruses from lake water and sediments by experimental inoculation JF - PLoS one N2 - Influenza A viruses (IAV) are zoonotic pathogens relevant to human, domestic animal and wildlife health. Many avian IAVs are transmitted among waterfowl via a faecal-oral-route. Therefore, environmental water where waterfowl congregate may play an important role in the ecology and epidemiology of avian IAV. Water and sediment may sustain and transmit virus among individuals or species. It is unclear at what concentrations waterborne viruses are infectious or remain detectable. To address this, we performed lake water and sediment dilution experiments with varying concentrations or infectious doses of four IAV strains from seal, turkey, duck and gull. To test for infectivity of the IAV strains in a concentration dependent manner, we applied cultivation to specific pathogen free (SPF) embryonated chicken eggs and Madin-Darby Canine Kidney (MDCK) cells. IAV recovery was more effective from embryonated chicken eggs than MDCK cells for freshwater lake dilutions, whereas, MDCK cells were more effective for viral recovery from sediment samples. Low infectious dose (1 PFU/200 mu L) was sufficient in most cases to detect and recover IAV from lake water dilutions. Sediment required higher initial infectious doses (>= 100 PFU/200 mu L). Y1 - 2019 U6 - https://doi.org/10.1371/journal.pone.0216880 SN - 1932-6203 VL - 14 IS - 5 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Tang, Kam W. A1 - Backhaus, Liv A1 - Riemann, Lasse A1 - Koski, Marja A1 - Grossart, Hans-Peter A1 - Munk, Peter A1 - Nielsen, Torkel Gissel T1 - Copepod carcasses in the subtropical convergence zone of the Sargasso Sea BT - implications for microbial community composition, system respiration and carbon flux JF - Journal of plankton research N2 - The oligotrophic subtropical gyre covers a vast area of the Atlantic Ocean. Decades of time-series monitoring have generated detailed temporal information about zooplankton species and abundances at fixed locations within the gyre, but their live/dead status is often omitted, especially in the dynamic subtropical convergence zone (STCZ) where the water column stratification pattern can change considerably across the front as warm and cold water masses converge. We conducted a detailed survey in the North Atlantic STCZ and showed that over 85% of the copepods were typically concentrated in the upper 200 m. Copepod carcasses were present in all samples and their proportional numerical abundances increased with depth, reaching up to 91% at 300-400 m. Overall, 14-19% of the copepods within the upper 200 m were carcasses. Shipboard experiments showed that during carcass decomposition, microbial respiration increased, and the bacterial community associated with the carcasses diverged from that in the ambient water. Combining field and experimental data, we estimated that decomposing copepod carcasses constitute a negligible oxygen sink in the STCZ, but sinking carcasses may represent an overlooked portion of the passive carbon sinking flux and should be incorporated in future studies of carbon flux in this area. KW - Sargasso Sea KW - subtropical convergence zone KW - zooplankton KW - carcasses KW - carbon sinking flux Y1 - 2019 U6 - https://doi.org/10.1093/plankt/fbz038 SN - 0142-7873 SN - 1464-3774 VL - 41 IS - 4 SP - 549 EP - 560 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Grossart, Hans-Peter A1 - Van den Wyngaert, Silke A1 - Kagami, Maiko A1 - Wurzbacher, Christian A1 - Cunliffe, Michael A1 - Rojas-Jimenz, Keilor T1 - Fungi in aquatic ecosystems JF - Nature reviews. Microbiology N2 - Fungi are phylogenetically and functionally diverse ubiquitous components of almost all ecosystems on Earth, including aquatic environments stretching from high montane lakes down to the deep ocean. Aquatic ecosystems, however, remain frequently overlooked as fungal habitats, although fungi potentially hold important roles for organic matter cycling and food web dynamics. Recent methodological improvements have facilitated a greater appreciation of the importance of fungi in many aquatic systems, yet a conceptual framework is still missing. In this Review, we conceptualize the spatiotemporal dimensions, diversity, functions and organismic interactions of fungi in structuring aquatic food webs. We focus on currently unexplored fungal diversity, highlighting poorly understood ecosystems, including emerging artificial aquatic habitats. Y1 - 2019 U6 - https://doi.org/10.1038/s41579-019-0175-8 SN - 1740-1526 SN - 1740-1534 VL - 17 IS - 6 SP - 339 EP - 354 PB - Nature Publ. Group CY - Basingstoke ER - TY - GEN A1 - Numberger, Daniela A1 - Dreier, Carola A1 - Vullioud, Colin A1 - Gabriel, Guelsah A1 - Greenwood, Alex D. A1 - Grossart, Hans-Peter T1 - Correction: Recovery of influenza A viruses from lake water and sediments by experimental inoculation (vol 14, e0216880, 2019) T2 - PLoS one Y1 - 2019 U6 - https://doi.org/10.1371/journal.pone.0218882 SN - 1932-6203 VL - 14 IS - 6 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Tiegs, Scott D. A1 - Costello, David M. A1 - Isken, Mark W. A1 - Woodward, Guy A1 - McIntyre, Peter B. A1 - Gessner, Mark O. A1 - Chauvet, Eric A1 - Griffiths, Natalie A. A1 - Flecker, Alex S. A1 - Acuna, Vicenc A1 - Albarino, Ricardo A1 - Allen, Daniel C. A1 - Alonso, Cecilia A1 - Andino, Patricio A1 - Arango, Clay A1 - Aroviita, Jukka A1 - Barbosa, Marcus V. M. A1 - Barmuta, Leon A. A1 - Baxter, Colden V. A1 - Bell, Thomas D. C. A1 - Bellinger, Brent A1 - Boyero, Luz A1 - Brown, Lee E. A1 - Bruder, Andreas A1 - Bruesewitz, Denise A. A1 - Burdon, Francis J. A1 - Callisto, Marcos A1 - Canhoto, Cristina A1 - Capps, Krista A. A1 - Castillo, Maria M. A1 - Clapcott, Joanne A1 - Colas, Fanny A1 - Colon-Gaud, Checo A1 - Cornut, Julien A1 - Crespo-Perez, Veronica A1 - Cross, Wyatt F. A1 - Culp, Joseph M. A1 - Danger, Michael A1 - Dangles, Olivier A1 - de Eyto, Elvira A1 - Derry, Alison M. A1 - Diaz Villanueva, Veronica A1 - Douglas, Michael M. A1 - Elosegi, Arturo A1 - Encalada, Andrea C. A1 - Entrekin, Sally A1 - Espinosa, Rodrigo A1 - Ethaiya, Diana A1 - Ferreira, Veronica A1 - Ferriol, Carmen A1 - Flanagan, Kyla M. A1 - Fleituch, Tadeusz A1 - Shah, Jennifer J. Follstad A1 - Frainer, Andre A1 - Friberg, Nikolai A1 - Frost, Paul C. A1 - Garcia, Erica A. A1 - Lago, Liliana Garcia A1 - Garcia Soto, Pavel Ernesto A1 - Ghate, Sudeep A1 - Giling, Darren P. A1 - Gilmer, Alan A1 - Goncalves, Jose Francisco A1 - Gonzales, Rosario Karina A1 - Graca, Manuel A. S. A1 - Grace, Mike A1 - Grossart, Hans-Peter A1 - Guerold, Francois A1 - Gulis, Vlad A1 - Hepp, Luiz U. A1 - Higgins, Scott A1 - Hishi, Takuo A1 - Huddart, Joseph A1 - Hudson, John A1 - Imberger, Samantha A1 - Iniguez-Armijos, Carlos A1 - Iwata, Tomoya A1 - Janetski, David J. A1 - Jennings, Eleanor A1 - Kirkwood, Andrea E. A1 - Koning, Aaron A. A1 - Kosten, Sarian A1 - Kuehn, Kevin A. A1 - Laudon, Hjalmar A1 - Leavitt, Peter R. A1 - Lemes da Silva, Aurea L. A1 - Leroux, Shawn J. A1 - Leroy, Carri J. A1 - Lisi, Peter J. A1 - MacKenzie, Richard A1 - Marcarelli, Amy M. A1 - Masese, Frank O. A1 - Mckie, Brendan G. A1 - Oliveira Medeiros, Adriana A1 - Meissner, Kristian A1 - Milisa, Marko A1 - Mishra, Shailendra A1 - Miyake, Yo A1 - Moerke, Ashley A1 - Mombrikotb, Shorok A1 - Mooney, Rob A1 - Moulton, Tim A1 - Muotka, Timo A1 - Negishi, Junjiro N. A1 - Neres-Lima, Vinicius A1 - Nieminen, Mika L. A1 - Nimptsch, Jorge A1 - Ondruch, Jakub A1 - Paavola, Riku A1 - Pardo, Isabel A1 - Patrick, Christopher J. A1 - Peeters, Edwin T. H. M. A1 - Pozo, Jesus A1 - Pringle, Catherine A1 - Prussian, Aaron A1 - Quenta, Estefania A1 - Quesada, Antonio A1 - Reid, Brian A1 - Richardson, John S. A1 - Rigosi, Anna A1 - Rincon, Jose A1 - Risnoveanu, Geta A1 - Robinson, Christopher T. A1 - Rodriguez-Gallego, Lorena A1 - Royer, Todd V. A1 - Rusak, James A. A1 - Santamans, Anna C. A1 - Selmeczy, Geza B. A1 - Simiyu, Gelas A1 - Skuja, Agnija A1 - Smykla, Jerzy A1 - Sridhar, Kandikere R. A1 - Sponseller, Ryan A1 - Stoler, Aaron A1 - Swan, Christopher M. A1 - Szlag, David A1 - Teixeira-de Mello, Franco A1 - Tonkin, Jonathan D. A1 - Uusheimo, Sari A1 - Veach, Allison M. A1 - Vilbaste, Sirje A1 - Vought, Lena B. M. A1 - Wang, Chiao-Ping A1 - Webster, Jackson R. A1 - Wilson, Paul B. A1 - Woelfl, Stefan A1 - Xenopoulos, Marguerite A. A1 - Yates, Adam G. A1 - Yoshimura, Chihiro A1 - Yule, Catherine M. A1 - Zhang, Yixin X. A1 - Zwart, Jacob A. T1 - Global patterns and drivers of ecosystem functioning in rivers and riparian zones JF - Science Advances N2 - River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale. Y1 - 2019 U6 - https://doi.org/10.1126/sciadv.aav0486 SN - 2375-2548 VL - 5 IS - 1 PB - American Assoc. for the Advancement of Science CY - Washington ER - TY - JOUR A1 - Kolmakova, Olesya V. A1 - Gladyshev, Michail I. A1 - Fonvielle, Jeremy Andre A1 - Ganzert, Lars A1 - Hornick, Thomas A1 - Grossart, Hans-Peter T1 - Effects of zooplankton carcasses degradation on freshwater bacterial community composition and implications for carbon cycling JF - Environmental microbiology N2 - Non-predatory mortality of zooplankton provides an abundant, yet, little studied source of high quality labile organic matter (LOM) in aquatic ecosystems. Using laboratory microcosms, we followed the decomposition of organic carbon of fresh C-13-labelled Daphnia carcasses by natural bacterioplankton. The experimental setup comprised blank microcosms, that is, artificial lake water without any organic matter additions (B), and microcosms either amended with natural humic matter (H), fresh Daphnia carcasses (D) or both, that is, humic matter and Daphnia carcasses (HD). Most of the carcass carbon was consumed and respired by the bacterial community within 15 days of incubation. A shift in the bacterial community composition shaped by labile carcass carbon and by humic matter was observed. Nevertheless, we did not observe a quantitative change in humic matter degradation by heterotrophic bacteria in the presence of LOM derived from carcasses. However, carcasses were the main factor driving the bacterial community composition suggesting that the presence of large quantities of dead zooplankton might affect the carbon cycling in aquatic ecosystems. Our results imply that organic matter derived from zooplankton carcasses is efficiently remineralized by a highly specific bacterial community, but does not interfere with the bacterial turnover of more refractory humic matter. Y1 - 2018 U6 - https://doi.org/10.1111/1462-2920.14418 SN - 1462-2912 SN - 1462-2920 VL - 21 IS - 1 SP - 34 EP - 49 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Block, Benjamin D. A1 - Denfeld, Blaize A. A1 - Stockwell, Jason D. A1 - Flaim, Giovanna A1 - Grossart, Hans-Peter A1 - Knoll, Lesley B. A1 - Maier, Dominique B. A1 - North, Rebecca L. A1 - Rautio, Milla A1 - Rusak, James A. A1 - Sadro, Steve A1 - Weyhenmeyer, Gesa A. A1 - Bramburger, Andrew J. A1 - Branstrator, Donn K. A1 - Salonen, Kalevi A1 - Hampton, Stephanie E. T1 - The unique methodological challenges of winter limnology JF - Limnology and Oceanography: Methods N2 - Winter is an important season for many limnological processes, which can range from biogeochemical transformations to ecological interactions. Interest in the structure and function of lake ecosystems under ice is on the rise. Although limnologists working at polar latitudes have a long history of winter work, the required knowledge to successfully sample under winter conditions is not widely available and relatively few limnologists receive formal training. In particular, the deployment and operation of equipment in below 0 degrees C temperatures pose considerable logistical and methodological challenges, as do the safety risks of sampling during the ice-covered period. Here, we consolidate information on winter lake sampling and describe effective methods to measure physical, chemical, and biological variables in and under ice. We describe variation in snow and ice conditions and discuss implications for sampling logistics and safety. We outline commonly encountered methodological challenges and make recommendations for best practices to maximize safety and efficiency when sampling through ice or deploying instruments in ice-covered lakes. Application of such practices over a broad range of ice-covered lakes will contribute to a better understanding of the factors that regulate lakes during winter and how winter conditions affect the subsequent ice-free period. Y1 - 2018 U6 - https://doi.org/10.1002/lom3.10295 SN - 1541-5856 VL - 17 IS - 1 SP - 42 EP - 57 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Steger, Kristin A1 - Kim, Amy Taeyen A1 - Ganzert, Lars A1 - Grossart, Hans-Peter A1 - Smart, David R. T1 - Floodplain soil and its bacterial composition are strongly affected by depth JF - FEMS microbiology ecology N2 - We studied bacterial abundance and community structure of five soil cores using high-throughput sequencing of the 16S rRNA gene. Shifts in the soil bacterial composition were more pronounced within a vertical profile than across the landscape. Soil organic carbon (SOC) and nitrogen (N) concentrations decreased exponentially with soil depth and revealed a buried carbon-rich horizon between 0.8 and 1.3 m across all soil cores. This buried horizon was phylogenetically similar to its surrounding subsoils supporting the idea that the type of carbon, not necessarily the amount of carbon was driving the apparent similarities. In contrast to other studies, Nitrospirae was one of our major phyla with relatively high abundances throughout the soil profile except for the surface soil. Although depth is the major driver shaping soil bacterial community structure, positive correlations with SOC and N concentrations, however, were revealed with the bacterial abundance of Acidobacteria, one of the major, and Gemmatimonadetes, one of the minor phyla in our study. Our study showed that bacterial diversity in soils below 2.0 m can be still as high if not higher than in the above laying subsurface soil suggesting that various bacteria throughout the soil profile influence major biogeochemical processes in floodplain soils. KW - 16S rRNA gene sequencing KW - alluvial soil KW - buried horizon KW - Nitrospirae KW - soil bacterial diversity KW - SOC Y1 - 2019 U6 - https://doi.org/10.1093/femsec/fiz014 SN - 0168-6496 SN - 1574-6941 VL - 95 IS - 3 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Beisner, Beatrix E. A1 - Grossart, Hans-Peter A1 - Gasol, Josep M. T1 - A guide to methods for estimating phago-mixotrophy in nanophytoplankton JF - Journal of plankton research N2 - Growing attention to phytoplankton mixotrophy as a trophic strategy has led to significant revisions of traditional pelagic food web models and ecosystem functioning. Although some empirical estimates of mixotrophy do exist, a much broader set of in situ measurements are required to (i) identify which organisms are acting as mixotrophs in real time and to (ii) assess the contribution of their heterotrophy to biogeochemical cycling. Estimates are needed through time and across space to evaluate which environmental conditions or habitats favour mixotrophy: conditions still largely unknown. We review methodologies currently available to plankton ecologists to undertake estimates of plankton mixotrophy, in particular nanophytoplankton phago-mixotrophy. Methods are based largely on fluorescent or isotopic tracers, but also take advantage of genomics to identify phylotypes and function. We also suggest novel methods on the cusp of use for phago-mixotrophy assessment, including single-cell measurements improving our capacity to estimate mixotrophic activity and rates in wild plankton communities down to the single-cell level. Future methods will benefit from advances in nanotechnology, micromanipulation and microscopy combined with stable isotope and genomic methodologies. Improved estimates of mixotrophy will enable more reliable models to predict changes in food web structure and biogeochemical flows in a rapidly changing world. KW - flow cytometry KW - phagotrophy KW - phytoplankton KW - methods KW - fluorescence KW - microscopy KW - FISH KW - isotopic methods KW - phylotypes KW - carbon flows KW - gene sequencing Y1 - 2019 U6 - https://doi.org/10.1093/plankt/fbz008 SN - 0142-7873 SN - 1464-3774 VL - 41 IS - 2 SP - 77 EP - 89 PB - Oxford Univ. Press CY - Oxford ER - TY - BOOK A1 - Schmidt, Thorsten Ingo T1 - Staatsrecht I BT - Staatsorganisationsrecht mit Verfassungsprozessrecht T3 - Prüfe dein Wissen N2 - Das Staatsrecht zählt sowohl in der Praxis als auch in der juristischen Prüfung zu den zentralen Rechtsgebieten. Das Staatsorganisationsrecht bestimmt Aufbau und Verfahren der Staatsorgane und beeinflusst durch den Vorrang der Verfassung die gesamte Rechtsordnung. Der Band behandelt anschaulich, umfassend und systematisch geordnet den gesamten Pflichtwahlstoff. In Form von Fällen und Fragen wird dabei unter Berücksichtigung der Rechtsprechung des Bundesverfassungsgerichts besonderer Wert auf die staatstheoretischen Grundlagen und die europarechtlichen Bezüge dieses Rechtsgebiets gelegt. Vorteile auf einen Blick - ausführliche Behandlung in Frageund-Antwort-Fällen - systematische und umfassende Darstellung aktuell auf neuestem Rechtsstand. Zur Neuauflage Für die 4. Auflage wurde das Werk in zwei Bände aufgeteilt. Band I enthält eine ausführliche Darstellung des Staatsorganisationsrechts. Berücksichtigt wurde dabei die umfangreiche neue Rechtsprechung des BVerfG zu diesem Rechtsbereich. Enthalten sind außerdem die aktuellen Einflüsse des europäischen Rechts und der Rechtsprechung des EGMR auf das deutsche Staatsrecht. Zielgruppe Für Studierende der Anfangs- und Fortgeschrittenensemester sowie zur Vorbereitung auf die Erste Juristische Staatsprüfung. Y1 - 2019 SN - 978-3-406-72883-9 PB - Beck CY - München ET - 4. überarb. Aufl. ER - TY - JOUR A1 - Wachs, Sebastian A1 - Wright, Michelle F. A1 - Sittichai, Ruthaychonnee A1 - Singh, Ritu A1 - Biswal, Ramakrishna A1 - Kim, Eun-mee A1 - Yang, Soeun A1 - Gámez-Guadix, Manuel A1 - Almendros, Carmen A1 - Flora, Katerina A1 - Daskalou, Vassiliki A1 - Maziridou, Evdoxia T1 - Associations between witnessing and perpetrating online hate in eight countries BT - the buffering effects of problem-focused coping JF - International Journal of Environmental Research and Public Health N2 - Online hate is a topic that has received considerable interest lately, as online hate represents a risk to self-determination and peaceful coexistence in societies around the globe. However, not much is known about the explanations for adolescents posting or forwarding hateful online material or how adolescents cope with this newly emerging online risk. Thus, we sought to better understand the relationship between a bystander to and perpetrator of online hate, and the moderating effects of problem-focused coping strategies (e.g., assertive, technical coping) within this relationship. Self-report questionnaires on witnessing and committing online hate and assertive and technical coping were completed by 6829 adolescents between 12 and 18 years of age from eight countries. The results showed that increases in witnessing online hate were positively related to being a perpetrator of online hate. Assertive and technical coping strategies were negatively related with perpetrating online hate. Bystanders of online hate reported fewer instances of perpetrating online hate when they reported higher levels of assertive and technical coping strategies, and more frequent instances of perpetrating online hate when they reported lower levels of assertive and technical coping strategies. In conclusion, our findings suggest that, if effective, prevention and intervention programs that target online hate should consider educating young people about problem-focused coping strategies, self-assertiveness, and media skills. Implications for future research are discussed. KW - online hate KW - hate speech KW - bystander KW - perpetrator KW - coping strategies KW - cyber aggression Y1 - 2019 U6 - https://doi.org/10.3390/ijerph16203992 SN - 1660-4601 VL - 16 IS - 20 PB - MDPI CY - Basel ER - TY - JOUR A1 - Grossart, Hans-Peter A1 - Massana, Ramon A1 - McMahon, Katherine D. A1 - Walsh, David A. T1 - Linking metagenomics to aquatic microbial ecology and biogeochemical cycles JF - Limnology and oceanography N2 - Microbial communities are essential components of aquatic ecosystems through their contribution to food web dynamics and biogeochemical processes. Aquatic microbial diversity is immense and a general challenge is to understand how metabolism and interactions of single organisms shape microbial community dynamics and ecosystem-scale biogeochemical transformations. Metagenomic approaches have developed rapidly, and proven to be powerful in linking microbial community dynamics to biogeochemical processes. In this review, we provide an overview of metagenomic approaches, followed by a discussion on some recent insights they have provided, including those in this special issue. These include the discovery of new taxa and metabolisms in aquatic microbiomes, insights into community assembly and functional ecology as well as evolutionary processes shaping microbial genomes and microbiomes, and the influence of human activities on aquatic microbiomes. Given that metagenomics can now be considered a mature technology where data generation and descriptive analyses are relatively routine and informative, we then discuss metagenomic-enabled research avenues to further link microbial dynamics to biogeochemical processes. These include the integration of metagenomics into well-designed ecological experiments, the use of metagenomics to inform and validate metabolic and biogeochemical models, and the pressing need for ecologically relevant model organisms and simple microbial systems to better interpret the taxonomic and functional information integrated in metagenomes. These research avenues will contribute to a more mechanistic and predictive understanding of links between microbial dynamics and biogeochemical cycles. Owing to rapid climate change and human impacts on aquatic ecosystems, the urgency of such an understanding has never been greater. Y1 - 2019 U6 - https://doi.org/10.1002/lno.11382 SN - 0024-3590 SN - 1939-5590 VL - 65 SP - S2 EP - S20 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Numberger, Daniela A1 - Riedel, Thomas A1 - McEwen, Gayle A1 - Nübel, Ulrich A1 - Frentrup, Martinique A1 - Schober, Isabel A1 - Bunk, Boyke A1 - Spröer, Cathrin A1 - Overmann, Jörg A1 - Grossart, Hans-Peter A1 - Greenwood, Alex D. T1 - Genomic analysis of three Clostridioides difficile isolates from urban water sources JF - Anaerobe N2 - We investigated inflow of a wastewater treatment plant and sediment of an urban lake for the presence of Clostridioides difficile by cultivation and PCR. Among seven colonies we sequenced the complete genomes of three: two non-toxigenic isolates from wastewater and one toxigenic isolate from the urban lake. For all obtained isolates, a close genomic relationship with human-derived isolates was observed. (C) 2019 Elsevier Ltd. All rights reserved. KW - Clostridioides difficile KW - Genomes KW - Sediment KW - Wastewater Y1 - 2019 U6 - https://doi.org/10.1016/j.anaerobe.2019.01.002 SN - 1075-9964 SN - 1095-8274 VL - 56 SP - 22 EP - 26 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Schorn, Sina A1 - Salman-Carvalho, Verena A1 - Littmann, Sten A1 - Ionescu, Danny A1 - Grossart, Hans-Peter A1 - Cypionka, Heribert T1 - Cell architecture of the giant sulfur bacterium achromatium oxaliferum BT - Extra-cytoplasmic localization of calcium carbonate bodies JF - FEMS Microbiology Ecology N2 - Achromatium oxaliferum is a large sulfur bacterium easily recognized by large intracellular calcium carbonate bodies. Although these bodies often fill major parts of the cells' volume, their role and specific intracellular location are unclear. In this study, we used various microscopy and staining techniques to identify the cell compartment harboring the calcium carbonate bodies. We observed that Achromatium cells often lost their calcium carbonate bodies, either naturally or induced by treatments with diluted acids, ethanol, sodium bicarbonate and UV radiation which did not visibly affect the overall shape and motility of the cells (except for UV radiation). The water-soluble fluorescent dye fluorescein easily diffused into empty cavities remaining after calcium carbonate loss. Membranes (stained with Nile Red) formed a network stretching throughout the cell and surrounding empty or filled calcium carbonate cavities. The cytoplasm (stained with FITC and SYBR Green for nucleic acids) appeared highly condensed and showed spots of dissolved Ca2+ (stained with Fura-2). From our observations, we conclude that the calcium carbonate bodies are located in the periplasm, in extra-cytoplasmic pockets of the cytoplasmic membrane and are thus kept separate from the cell's cytoplasm. This periplasmic localization of the carbonate bodies might explain their dynamic formation and release upon environmental changes. KW - sulfur-bacteria KW - calcium carbonate inclusions KW - extra-cytoplasmic pockets KW - calcite Y1 - 2019 U6 - https://doi.org/10.1093/femsec/fiz200 SN - 1574-6941 VL - 96 IS - 2 SP - 1 EP - 8 PB - Oxford University Press CY - Oxford ER - TY - THES A1 - Laudan, Jonas T1 - Changing susceptibility of flood-prone residents in Germany T1 - Die Änderung der Anfälligkeit von Hochwassergefährdeten Anwohnern in Deutschland BT - mental coping and mitigation behaviour in the context of different flood types BT - Mentale Bewältigung und Schadensminderungsverhalten im Zusammenhang mit Verschiedenen Hochwassertypen N2 - Floods are among the most costly natural hazards that affect Europe and Germany, demanding a continuous adaptation of flood risk management. While social and economic development in recent years altered the flood risk patterns mainly with regard to an increase in flood exposure, different flood events are further expected to increase in frequency and severity in certain European regions due to climate change. As a result of recent major flood events in Germany, the German flood risk management shifted to more integrated approaches that include private precaution and preparation to reduce the damage on exposed assets. Yet, detailed insights into the preparedness decisions of flood-prone households remain scarce, especially in connection to mental impacts and individual coping strategies after being affected by different flood types. This thesis aims to gain insights into flash floods as a costly hazard in certain German regions and compares the damage driving factors to the damage driving factors of river floods. Furthermore, psychological impacts as well as the effects on coping and mitigation behaviour of flood-affected households are assessed. In this context, psychological models such as the Protection Motivation Theory (PMT) and methods such as regressions and Bayesian statistics are used to evaluate influencing factors on the mental coping after an event and to identify psychological variables that are connected to intended private flood mitigation. The database consists of surveys that were conducted among affected households after major river floods in 2013 and flash floods in 2016. The main conclusions that can be drawn from this thesis reveal that the damage patterns and damage driving factors of strong flash floods differ significantly from those of river floods due to a rapid flow origination process, higher flow velocities and flow forces. However, the effects on mental coping of people that have been affected by flood events appear to be weakly influenced by different flood types, but yet show a coherence to the event severity, where often thinking of the respective event is pronounced and also connected to a higher mitigation motivation. The mental coping and preparation after floods is further influenced by a good information provision and a social environment, which encourages a positive attitude towards private mitigation. As an overall recommendation, approaches for an integrated flood risk management in Germany should be followed that also take flash floods into account and consider psychological characteristics of affected households to support and promote private flood mitigation. Targeted information campaigns that concern coping options and discuss current flood risks are important to better prepare for future flood hazards in Germany. N2 - Hochwasser zählen zu den schadensträchtigsten Naturgefahren, die in Europa und Deutschland vorkommen. In Deutschland traten in den letzten Jahren einige sehr starke Hochwasser und Überflutungen auf, die die Einstufung von Hochwassern als gefährliche Naturgewalt bestätigten. Private Haushalte leiden unter finanziellen und persönlichen Verlusten und sind sogar teilweise mehrfach betroffen. Folgenreiche Hochwasser, die im Gedächtnis blieben, waren insbesondere das Elbe-Hochwasser im Sommer 2002 sowie Überschwemmungen mit Schwerpukten an Elbe und Donau im Juni 2013. Im Mai und Juni 2016 kam es zu heftigen Unwettern über Zentraleuropa, während insbesondere Süddeutschland von Starkregen und Sturzfluten betroffen war. Hierbei wurden vereinzelte Ortschaften in Baden-Württtemberg (vor allem Braunsbach) und Bayern (vor allem Simbach am Inn) von extremen Sturzfluten beeinträchtigt und Bauwerke stark beschädigt. Als Reaktion auf die Flusshochwasser 2002 und 2013 wurde unter anderem das aktuelle Hochwasserrisikomanagement in Deutschland so angepasst, dass neben übergeordneten und technischen Hochwasserschutzmaßnahmen auch auf lokaler Ebene Maßnahmen ergriffen werden müssen. Diese umfassen Hochwasservorsorgemaßnahmen, die betroffene Haushalte selbst implementieren sollen. Neben strukturellen Maßnahmen wie z.B. der Verlegung von Heizung, Elektronik und Öltank in nicht-gefährdete Stockwerke sowie dem Schutz des Gebäudes vor Eindringen von Wasser, können auch nichtstrukturelle Maßnahmen, wie z.B. eine angepasste Wohnraumnutzung und das Verwenden von geeigneter Inneneinrichtung, ergriffen werden, um Hochwasserschäden signifikant zu verringern. Bis heute ist es jedoch unklar, aus welchen Gründen sich die betroffenen Menschen für Hochwasservorsorgemaßnahmen entscheiden und wie die individuelle Motivation, Maßnahmen zu implementieren, verstärkt werden kann. Neben dem Wissen um die eigene Hochwassergefährdung ist anzunehmen, dass die Selbsteinschätzung in Bezug auf einen wirksamen Umgang mit Hochwassern ausschlaggebend für die Motivation zur Vorsorge ist. Außerdem kann davon ausgegangen werden, dass verschiedene Hochwassertypen wie Flusshochwasser und Sturzfluten mit ihren unterschiedlichen Dynamiken unterschiedliche Auswirkungen auf die mentale Bewältigung und somit auch auf das Vorsorgeverhalten hervorrufen. Die vorliegende Arbeit hat demnach zum Ziel, Flusshochwasser und Sturzfluten in Deutschland miteinander zu vergleichen, wobei der Fokus auf schadenstreibenden Faktoren und psychologischen Auswirkungen auf betroffene Haushalte liegt. Weiterhin sollen damit verbundenes Vorsorgeverhalten untersucht und gegebenenfalls Handlungsempfehlungen für das Hochwasserrisikomanagement abgeleitet werden, das einerseits psychologische Charakteristika und andererseits Sturzfluten als signifikante Naturgefahr in Deutschland miteinbezieht. Hierbei werden sozio-ökonomische, zwischenmenschliche und psychologische Variablen von Haushalten ausgewertet, die 2013 und 2016 von Flusshochwassern und Sturzfluten betroffen waren. Dabei kommen verschiedene Methoden (Regressionen, Bayessche Statistik) und Modelle (Protection Motivation Theory) zum Einsatz, um Verbindungen zwischen den Variablen aufzeigen. Die Ergebnisse veranschaulichen erstens, dass Flusshochwasser und Sturzfluten zwar unterschiedliche Schäden an Gebäuden aufgrund verschiedener Flutdynamiken hervorrufen können, was sich bei Betroffenen jedoch nicht in unterschiedlichen psychologischen Auswirkungen widerspiegelt. Vielmehr ist die jeweilige Stärke und Schwere des Hochwassers entscheidend für charakteristische Ausprägungen von psychologischen Variablen. In diesem Falle sorgt eine stärkere Flut dafür, dass häufiger an das jeweilige Ereignis gedacht wird, während die Motivation zur Eigenvorsorge in solchen Fällen erhöht scheint. Zweitens sind ein soziales Umfeld, in dem bereits Vorsorgemaßnahmen implementiert wurden, sowie hilfreiche Informationen für geeignete Maßnahmen, deren Kosten und Aufklärung über das aktuelle Hochwasserrisiko förderlich für die Motivation, private Vorsorge zu betreiben. Ein aktuelles Hochwasserrisikomanagement sollte demnach auch Sturzfluten als mögliches Risiko in Deutschland miteinbeziehen und mehr in die Aufklärung und private Unterstützung bei Hochwassern investieren. Ein besseres Verstehen von psychologischen und mentalen Auswirkungen von verschiedenen Hochwassertypen hat den Vorteil, dass Hilfe und Informationskampagnen individuell und effizient gestaltet, Schäden minimiert und Schadensprognosen aufgrund der genaueren Kenntnisse über Vorsorgeverhalten verbessert werden können. KW - floods KW - psychology KW - flash floods KW - Hochwasser KW - Psychologie KW - Sturzfluten Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-434421 ER - TY - GEN A1 - Agarwal, Ankit A1 - Caesar, Levke A1 - Marwan, Norbert A1 - Maheswaran, Rathinasamy A1 - Merz, Bruno T1 - Network-based identification and characterization of teleconnections on different scales T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Sea surface temperature (SST) patterns can – as surface climate forcing – affect weather and climate at large distances. One example is El Niño-Southern Oscillation (ENSO) that causes climate anomalies around the globe via teleconnections. Although several studies identified and characterized these teleconnections, our understanding of climate processes remains incomplete, since interactions and feedbacks are typically exhibited at unique or multiple temporal and spatial scales. This study characterizes the interactions between the cells of a global SST data set at different temporal and spatial scales using climate networks. These networks are constructed using wavelet multi-scale correlation that investigate the correlation between the SST time series at a range of scales allowing instantaneously deeper insights into the correlation patterns compared to traditional methods like empirical orthogonal functions or classical correlation analysis. This allows us to identify and visualise regions of – at a certain timescale – similarly evolving SSTs and distinguish them from those with long-range teleconnections to other ocean regions. Our findings re-confirm accepted knowledge about known highly linked SST patterns like ENSO and the Pacific Decadal Oscillation, but also suggest new insights into the characteristics and origins of long-range teleconnections like the connection between ENSO and Indian Ocean Dipole. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 731 Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-430520 SN - 1866-8372 IS - 731 ER - TY - GEN A1 - Sieg, Tobias A1 - Vogel, Kristin A1 - Merz, Bruno A1 - Kreibich, Heidi T1 - Seamless Estimation of Hydrometeorological Risk Across Spatial Scales T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Hydrometeorological hazards caused losses of approximately 110 billion U.S. Dollars in 2016 worldwide. Current damage estimations do not consider the uncertainties in a comprehensive way, and they are not consistent between spatial scales. Aggregated land use data are used at larger spatial scales, although detailed exposure data at the object level, such as openstreetmap.org, is becoming increasingly available across the globe.We present a probabilistic approach for object-based damage estimation which represents uncertainties and is fully scalable in space. The approach is applied and validated to company damage from the flood of 2013 in Germany. Damage estimates are more accurate compared to damage models using land use data, and the estimation works reliably at all spatial scales. Therefore, it can as well be used for pre-event analysis and risk assessments. This method takes hydrometeorological damage estimation and risk assessments to the next level, making damage estimates and their uncertainties fully scalable in space, from object to country level, and enabling the exploitation of new exposure data. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 743 KW - spatial scales KW - risk assessment KW - hydro-meterological hazards KW - object-based damage modeling KW - uncertainty KW - probabilistic approaches Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-435341 SN - 1866-8372 IS - 743 SP - 574 EP - 581 ER - TY - JOUR A1 - Cao, Xing A1 - Ni, Binbin A1 - Summers, Danny A1 - Shprits, Yuri A1 - Gu, Xudong A1 - Fu, Song A1 - Lou, Yuequn A1 - Zhang, Yang A1 - Ma, Xin A1 - Zhang, Wenxun A1 - Huang, He A1 - Yi, Juan T1 - Sensitivity of EMIC wave-driven scattering loss of ring current protons to wave normal angle distribution JF - Geophysical research letters N2 - Electromagnetic ion cyclotron waves have long been recognized to play a crucial role in the dynamic loss of ring current protons. While the field-aligned propagation approximation of electromagnetic ion cyclotron waves was widely used to quantify the scattering loss of ring current protons, in this study, we find that the wave normal distribution strongly affects the pitch angle scattering efficiency of protons. Increase of peak normal angle or angular width can considerably reduce the scattering rates of <= 10 keV protons. For >10 keV protons, the field-aligned propagation approximation results in a pronounced underestimate of the scattering of intermediate equatorial pitch angle protons and overestimates the scattering of high equatorial pitch angle protons by orders of magnitude. Our results suggest that the wave normal distribution of electromagnetic ion cyclotron waves plays an important role in the pitch angle evolution and scattering loss of ring current protons and should be incorporated in future global modeling of ring current dynamics. Y1 - 2019 U6 - https://doi.org/10.1029/2018GL081550 SN - 0094-8276 SN - 1944-8007 VL - 46 IS - 2 SP - 590 EP - 598 PB - American Geophysical Union CY - Washington ER - TY - GEN A1 - Cabalar, Pedro A1 - Fandiño, Jorge A1 - Schaub, Torsten A1 - Schellhorn, Sebastian T1 - Lower Bound Founded Logic of Here-and-There T2 - Logics in Artificial Intelligence N2 - A distinguishing feature of Answer Set Programming is that all atoms belonging to a stable model must be founded. That is, an atom must not only be true but provably true. This can be made precise by means of the constructive logic of Here-and-There, whose equilibrium models correspond to stable models. One way of looking at foundedness is to regard Boolean truth values as ordered by letting true be greater than false. Then, each Boolean variable takes the smallest truth value that can be proven for it. This idea was generalized by Aziz to ordered domains and applied to constraint satisfaction problems. As before, the idea is that a, say integer, variable gets only assigned to the smallest integer that can be justified. In this paper, we present a logical reconstruction of Aziz’ idea in the setting of the logic of Here-and-There. More precisely, we start by defining the logic of Here-and-There with lower bound founded variables along with its equilibrium models and elaborate upon its formal properties. Finally, we compare our approach with related ones and sketch future work. Y1 - 2019 SN - 978-3-030-19570-0 SN - 978-3-030-19569-4 U6 - https://doi.org/10.1007/978-3-030-19570-0_34 SN - 0302-9743 SN - 1611-3349 VL - 11468 SP - 509 EP - 525 PB - Springer CY - Cham ER - TY - JOUR A1 - Sieg, Tobias A1 - Schinko, Thomas A1 - Vogel, Kristin A1 - Mechler, Reinhard A1 - Merz, Bruno A1 - Kreibich, Heidi T1 - Integrated assessment of short-term direct and indirect economic flood impacts including uncertainty quantification JF - PLoS ONE N2 - Understanding and quantifying total economic impacts of flood events is essential for flood risk management and adaptation planning. Yet, detailed estimations of joint direct and indirect flood-induced economic impacts are rare. In this study an innovative modeling procedure for the joint assessment of short-term direct and indirect economic flood impacts is introduced. The procedure is applied to 19 economic sectors in eight federal states of Germany after the flood events in 2013. The assessment of the direct economic impacts is object-based and considers uncertainties associated with the hazard, the exposed objects and their vulnerability. The direct economic impacts are then coupled to a supply-side Input-Output-Model to estimate the indirect economic impacts. The procedure provides distributions of direct and indirect economic impacts which capture the associated uncertainties. The distributions of the direct economic impacts in the federal states are plausible when compared to reported values. The ratio between indirect and direct economic impacts shows that the sectors Manufacturing, Financial and Insurance activities suffered the most from indirect economic impacts. These ratios also indicate that indirect economic impacts can be almost as high as direct economic impacts. They differ strongly between the economic sectors indicating that the application of a single factor as a proxy for the indirect impacts of all economic sectors is not appropriate. KW - June 2013 KW - Damage KW - Model KW - Inoperability KW - Disasters KW - Hazards KW - Germany KW - Losses KW - Event KW - Costs Y1 - 2019 U6 - https://doi.org/10.1371/journal.pone.0212932 SN - 1932-6203 VL - 14 IS - 4 PB - Public Library of Science CY - San Francisco ER - TY - JOUR A1 - Sieg, Tobias A1 - Vogel, Kristin A1 - Merz, Bruno A1 - Kreibich, Heidi T1 - Seamless Estimation of Hydrometeorological Risk Across Spatial Scales JF - Earth's Future N2 - Hydrometeorological hazards caused losses of approximately 110 billion U.S. Dollars in 2016 worldwide. Current damage estimations do not consider the uncertainties in a comprehensive way, and they are not consistent between spatial scales. Aggregated land use data are used at larger spatial scales, although detailed exposure data at the object level, such as openstreetmap.org, is becoming increasingly available across the globe.We present a probabilistic approach for object-based damage estimation which represents uncertainties and is fully scalable in space. The approach is applied and validated to company damage from the flood of 2013 in Germany. Damage estimates are more accurate compared to damage models using land use data, and the estimation works reliably at all spatial scales. Therefore, it can as well be used for pre-event analysis and risk assessments. This method takes hydrometeorological damage estimation and risk assessments to the next level, making damage estimates and their uncertainties fully scalable in space, from object to country level, and enabling the exploitation of new exposure data. KW - spatial scales KW - risk assessment KW - hydro-meterological hazards KW - object-based damage modeling KW - uncertainty KW - probabilistic approaches Y1 - 2019 U6 - https://doi.org/10.1029/2018EF001122 SN - 2328-4277 VL - 7 IS - 5 SP - 574 EP - 581 PB - Wiley-Blackwell CY - Hoboken, NJ ER - TY - JOUR A1 - Nguyen Le Duy, A1 - Nguyen Viet Du, A1 - Heidbüchel, Ingo A1 - Meyer, Hanno A1 - Weiler, Markus A1 - Merz, Bruno A1 - Apel, Heiko T1 - Identification of groundwater mean transit times of precipitation and riverbank infiltration by two-component lumped parameter models JF - Hydrological processes N2 - Groundwater transit time is an essential hydrologic metric for groundwater resources management. However, especially in tropical environments, studies on the transit time distribution (TTD) of groundwater infiltration and its corresponding mean transit time (mTT) have been extremely limited due to data sparsity. In this study, we primarily use stable isotopes to examine the TTDs and their mTTs of both vertical and horizontal infiltration at a riverbank infiltration area in the Vietnamese Mekong Delta (VMD), representative of the tropical climate in Asian monsoon regions. Precipitation, river water, groundwater, and local ponding surface water were sampled for 3 to 9 years and analysed for stable isotopes (delta O-18 and delta H-2), providing a unique data set of stable isotope records for a tropical region. We quantified the contribution that the two sources contributed to the local shallow groundwater by a novel concept of two-component lumped parameter models (LPMs) that are solved using delta O-18 records. The study illustrates that two-component LPMs, in conjunction with hydrological and isotopic measurements, are able to identify subsurface flow conditions and water mixing at riverbank infiltration systems. However, the predictive skill and the reliability of the models decrease for locations farther from the river, where recharge by precipitation dominates, and a low-permeable aquitard layer above the highly permeable aquifer is present. This specific setting impairs the identifiability of model parameters. For river infiltration, short mTTs (<40 weeks) were determined for sites closer to the river (<200 m), whereas for the precipitation infiltration, the mTTs were longer (>80 weeks) and independent of the distance to the river. The results not only enhance the understanding of the groundwater recharge dynamics in the VMD but also suggest that the highly complex mechanisms of surface-groundwater interaction can be conceptualized by exploiting two-component LPMs in general. The model concept could thus be a powerful tool for better understanding both the hydrological functioning of mixing processes and the movement of different water components in riverbank infiltration systems. KW - bank infiltration KW - groundwater KW - lumped parameter model KW - mean transit time KW - Mekong Delta KW - stable isotopes Y1 - 2019 U6 - https://doi.org/10.1002/hyp.13549 SN - 0885-6087 SN - 1099-1085 VL - 33 IS - 24 SP - 3098 EP - 3118 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Rözer, Viktor A1 - Kreibich, Heidi A1 - Schröter, Kai A1 - Müller, Meike A1 - Sairam, Nivedita A1 - Doss-Gollin, James A1 - Lall, Upmanu A1 - Merz, Bruno T1 - Probabilistic Models Significantly Reduce Uncertainty in Hurricane Harvey Pluvial Flood Loss Estimates JF - Earths future N2 - Pluvial flood risk is mostly excluded in urban flood risk assessment. However, the risk of pluvial flooding is a growing challenge with a projected increase of extreme rainstorms compounding with an ongoing global urbanization. Considered as a flood type with minimal impacts when rainfall rates exceed the capacity of urban drainage systems, the aftermath of rainfall-triggered flooding during Hurricane Harvey and other events show the urgent need to assess the risk of pluvial flooding. Due to the local extent and small-scale variations, the quantification of pluvial flood risk requires risk assessments on high spatial resolutions. While flood hazard and exposure information is becoming increasingly accurate, the estimation of losses is still a poorly understood component of pluvial flood risk quantification. We use a new probabilistic multivariable modeling approach to estimate pluvial flood losses of individual buildings, explicitly accounting for the associated uncertainties. Except for the water depth as the common most important predictor, we identified the drivers for having loss or not and for the degree of loss to be different. Applying this approach to estimate and validate building structure losses during Hurricane Harvey using a property level data set, we find that the reliability and dispersion of predictive loss distributions vary widely depending on the model and aggregation level of property level loss estimates. Our results show that the use of multivariable zero-inflated beta models reduce the 90% prediction intervalsfor Hurricane Harvey building structure loss estimates on average by 78% (totalling U.S.$3.8 billion) compared to commonly used models. KW - pluvial flooding KW - loss modeling KW - urban flooding KW - probabilistic KW - Hurricane Harvey KW - climate change adaptation Y1 - 2019 U6 - https://doi.org/10.1029/2018EF001074 SN - 2328-4277 VL - 7 IS - 4 SP - 384 EP - 394 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Steirou, Eva A1 - Gerlitz, Lars A1 - Apel, Heiko A1 - Sun, Xun A1 - Merz, Bruno T1 - Climate influences on flood probabilities across Europe JF - Hydrology and earth system sciences : HESS N2 - The link between streamflow extremes and climatology has been widely studied in recent decades. However, a study investigating the effect of large-scale circulation variations on the distribution of seasonal discharge extremes at the European level is missing. Here we fit a climate-informed generalized extreme value (GEV) distribution to about 600 streamflow records in Europe for each of the standard seasons, i.e., to winter, spring, summer and autumn maxima, and compare it with the classical GEV distribution with parameters invariant in time. The study adopts a Bayesian framework and covers the period 1950 to 2016. Five indices with proven influence on the European climate are examined independently as covariates, namely the North Atlantic Oscillation (NAO), the east Atlantic pattern (EA), the east Atlantic-western Russian pattern (EA/WR), the Scandinavia pattern (SCA) and the polar-Eurasian pattern (POL). It is found that for a high percentage of stations the climate-informed model is preferred to the classical model. Particularly for NAO during winter, a strong influence on streamflow extremes is detected for large parts of Europe (preferred to the classical GEV distribution for 46% of the stations). Climate-informed fits are characterized by spatial coherence and form patterns that resemble relations between the climate indices and seasonal precipitation, suggesting a prominent role of the considered circulation modes for flood generation. For certain regions, such as northwestern Scandinavia and the British Isles, yearly variations of the mean seasonal climate indices result in considerably different extreme value distributions and thus in highly different flood estimates for individual years that can also persist for longer time periods. Y1 - 2019 U6 - https://doi.org/10.5194/hess-23-1305-2019 SN - 1027-5606 SN - 1607-7938 VL - 23 IS - 3 SP - 1305 EP - 1322 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - He, Zhihua A1 - Unger-Shayesteh, Katy A1 - Vorogushyn, Sergiy A1 - Weise, Stephan M. A1 - Kalashnikova, Olga A1 - Gafurov, Abror A1 - Duethmann, Doris A1 - Barandun, Martina A1 - Merz, Bruno T1 - Constraining hydrological model parameters using water isotopic compositions in a glacierized basin, Central Asia JF - Journal of hydrology N2 - Water stable isotope signatures can provide valuable insights into the catchment internal runoff processes. However, the ability of the water isotope data to constrain the internal apportionments of runoff components in hydrological models for glacierized basins is not well understood. This study developed an approach to simultaneously model the water stable isotopic compositions and runoff processes in a glacierized basin in Central Asia. The fractionation and mixing processes of water stable isotopes in and from the various water sources were integrated into a glacio-hydrological model. The model parameters were calibrated on discharge, snow cover and glacier mass balance data, and additionally isotopic composition of streamflow. We investigated the value of water isotopic compositions for the calibration of model parameters, in comparison to calibration methods without using such measurements. Results indicate that: (1) The proposed isotope-hydrological integrated modeling approach was able to reproduce the isotopic composition of streamflow, and improved the model performance in the evaluation period; (2) Involving water isotopic composition for model calibration reduced the model parameter uncertainty, and helped to reduce the uncertainty in the quantification of runoff components; (3) The isotope-hydrological integrated modeling approach quantified the contributions of runoff components comparably to a three-component tracer-based end-member mixing analysis method for summer peak flows, and required less water tracer data. Our findings demonstrate the value of water isotopic compositions to improve the quantification of runoff components using hydrological models in glacierized basins. KW - Water stable isotope KW - Isotope-hydrological integrated modeling KW - Quantification of runoff components KW - Glacierized basins Y1 - 2019 U6 - https://doi.org/10.1016/j.jhydrol.2019.01.048 SN - 0022-1694 SN - 1879-2707 VL - 571 SP - 332 EP - 348 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Ganguli, Poulomi A1 - Merz, Bruno T1 - Trends in Compound Flooding in Northwestern Europe During 1901-2014 JF - Geophysical research letters N2 - We analyze trends in compound flooding resulting from high coastal water levels (HCWLs) and peak river discharge over northwestern Europe during 1901-2014. Compound peak discharge associated with 37 stream gauges with at least 70 years of record availability near the North and Baltic Sea coasts is used. Compound flooding is assessed using a newly developed index, compound hazard ratio, that compares the severity of river flooding associated with HCWL with the at-site, T-year (a flood with 1/T chance of being exceeded in any given year) fluvial peak discharge. Our findings suggest a spatially coherent pattern in the dependence between HCWL and river peaks and in compound flood magnitudes and frequency. For higher return levels, we find upward trends in compound hazard ratio frequency at midlatitudes (gauges from 47 degrees N to 60 degrees N) and downward trends along the high latitude (>60 degrees N) regions of northwestern Europe. Plain Language Summary Compound floods in delta areas, that is, the co-occurrence of high coastal water levels (HCWLs) and high river discharge, are a particular challenge for disaster management. Such events are caused by two distinct mechanisms: (1) HCWLs may affect river flows and water levels by backwater effects or by reversing the seaward flow of rivers, particularly in regions with elevation less than 10 m in northwestern Europe. (2) The correlation between HCWL and river flow peaks may also stem from a common meteorological driver. Severe storm periods may be associated with high winds leading to storm surges, and at the same time with high precipitation followed by inland flooding. Understanding the historical trends in compound flooding, owing to changes in relative sea levels, in river flooding and in the dependence between these two drivers, is essential for projecting future changes and disaster management. The risk assessment frameworks are often limited to assessing flood risk from a single driver only. We present a new approach to assess compound flood severity resulting from extreme coastal water level and peak river discharge. We find upward trends in compound flooding for midlatitude regions and downward trends for high latitudes in northwestern Europe. KW - compound flood KW - northwestern Europe KW - risk modeling KW - dependence Y1 - 2019 U6 - https://doi.org/10.1029/2019GL084220 SN - 0094-8276 SN - 1944-8007 VL - 46 IS - 19 SP - 10810 EP - 10820 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Sairam, Nivedita A1 - Schroeter, Kai A1 - Rözer, Viktor A1 - Merz, Bruno A1 - Kreibich, Heidi T1 - Hierarchical Bayesian Approach for Modeling Spatiotemporal Variability in Flood Damage Processes JF - Water resources research N2 - Flood damage processes are complex and vary between events and regions. State-of-the-art flood loss models are often developed on the basis of empirical damage data from specific case studies and do not perform well when spatially and temporally transferred. This is due to the fact that such localized models often cover only a small set of possible damage processes from one event and a region. On the other hand, a single generalized model covering multiple events and different regions ignores the variability in damage processes across regions and events due to variables that are not explicitly accounted for individual households. We implement a hierarchical Bayesian approach to parameterize widely used depth-damage functions resulting in a hierarchical (multilevel) Bayesian model (HBM) for flood loss estimation that accounts for spatiotemporal heterogeneity in damage processes. We test and prove the hypothesis that, in transfer scenarios, HBMs are superior compared to generalized and localized regression models. In order to improve loss predictions for regions and events for which no empirical damage data are available, we use variables pertaining to specific region- and event-characteristics representing commonly available expert knowledge as group-level predictors within the HBM. KW - flood risk KW - flood loss model transfer KW - multilevel probabilistic flood loss model Y1 - 2019 U6 - https://doi.org/10.1029/2019WR025068 SN - 0043-1397 SN - 1944-7973 VL - 55 IS - 10 SP - 8223 EP - 8237 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Ganguli, Poulomi A1 - Merz, Bruno T1 - Extreme Coastal Water Levels Exacerbate Fluvial Flood Hazards in Northwestern Europe JF - Scientific reports N2 - Compound flooding, such as the co-occurrence of fluvial floods and extreme coastal water levels (CWL), may lead to significant impacts in densely-populated Low Elevation Coastal Zones. They may overstrain disaster management owing to the co-occurrence of inundation from rivers and the sea. Recent studies are limited by analyzing joint dependence between river discharge and either CWL or storm surges, and little is known about return levels of compound flooding, accounting for the covariance between drivers. Here, we assess the compound flood severity and identify hotspots for northwestern Europe during 1970–2014, using a newly developed Compound Hazard Ratio (CHR) that compares the severity of compound flooding associated with extreme CWL with the unconditional T-year fluvial peak discharge. We show that extreme CWL and stronger storms greatly amplify fluvial flood hazards. Our results, based on frequency analyses of observational records during 2013/2014’s winter storm Xaver, reveal that the river discharge of the 50-year compound flood is up to 70% larger, conditioned on the occurrence of extreme CWL, than that of the at-site peak discharge. For this event, nearly half of the stream gauges show increased flood hazards, demonstrating the importance of including the compounding effect of extreme CWL in river flood risk management. Y1 - 2019 U6 - https://doi.org/10.1038/s41598-019-49822-6 SN - 2045-2322 VL - 9 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Wendi, Dadiyorto A1 - Merz, Bruno A1 - Marwan, Norbert T1 - Assessing hydrograph similarity and rare runoff dynamics by cross recurrence plots JF - Water resources research N2 - This paper introduces a novel measure to assess similarity between event hydrographs. It is based on cross recurrence plots (CRP) and recurrence quantification analysis (RQA), which have recently gained attention in a range of disciplines when dealing with complex systems. The method attempts to quantify the event runoff dynamics and is based on the time delay embedded phase space representation of discharge hydrographs. A phase space trajectory is reconstructed from the event hydrograph, and pairs of hydrographs are compared to each other based on the distance of their phase space trajectories. Time delay embedding allows considering the multidimensional relationships between different points in time within the event. Hence, the temporal succession of discharge values is taken into account, such as the impact of the initial conditions on the runoff event. We provide an introduction to cross recurrence plots and discuss their parameterization. An application example based on flood time series demonstrates how the method can be used to measure the similarity or dissimilarity of events, and how it can be used to detect events with rare runoff dynamics. It is argued that this methods provides a more comprehensive approach to quantify hydrograph similarity compared to conventional hydrological signatures. KW - runoff dynamics KW - cross recurrence plot in hydrology KW - rare flood dynamics KW - hydrograph similarity KW - time delay embedding for runoff series Y1 - 2019 U6 - https://doi.org/10.1029/2018WR024111 SN - 0043-1397 SN - 1944-7973 VL - 55 IS - 6 SP - 4704 EP - 4726 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Sairam, Nivedita A1 - Schröter, Kai A1 - Lüdtke, Stefan A1 - Merz, Bruno A1 - Kreibich, Heidi T1 - Quantifying Flood Vulnerability Reduction via Private Precaution JF - Earth future N2 - Private precaution is an important component in contemporary flood risk management and climate adaptation. However, quantitative knowledge about vulnerability reduction via private precautionary measures is scarce and their effects are hardly considered in loss modeling and risk assessments. However, this is a prerequisite to enable temporally dynamic flood damage and risk modeling, and thus the evaluation of risk management and adaptation strategies. To quantify the average reduction in vulnerability of residential buildings via private precaution empirical vulnerability data (n = 948) is used. Households with and without precautionary measures undertaken before the flood event are classified into treatment and nontreatment groups and matched. Postmatching regression is used to quantify the treatment effect. Additionally, we test state-of-the-art flood loss models regarding their capability to capture this difference in vulnerability. The estimated average treatment effect of implementing private precaution is between 11 and 15 thousand EUR per household, confirming the significant effectiveness of private precautionary measures in reducing flood vulnerability. From all tested flood loss models, the expert Bayesian network-based model BN-FLEMOps and the rule-based loss model FLEMOps perform best in capturing the difference in vulnerability due to private precaution. Thus, the use of such loss models is suggested for flood risk assessments to effectively support evaluations and decision making for adaptable flood risk management. KW - flood loss KW - average treatment effect KW - matching methods KW - loss models KW - risk analysis KW - adaptation Y1 - 2019 U6 - https://doi.org/10.1029/2018EF000994 SN - 2328-4277 VL - 7 IS - 3 SP - 235 EP - 249 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Tarasova, Larisa A1 - Merz, Ralf A1 - Kiss, Andrea A1 - Basso, Stefano A1 - Blöchl, Günter A1 - Merz, Bruno A1 - Viglione, Alberto A1 - Plötner, Stefan A1 - Guse, Björn A1 - Schumann, Andreas A1 - Fischer, Svenja A1 - Ahrens, Bodo A1 - Anwar, Faizan A1 - Bárdossy, András A1 - Bühler, Philipp A1 - Haberlandt, Uwe A1 - Kreibich, Heidi A1 - Krug, Amelie A1 - Lun, David A1 - Müller-Thomy, Hannes A1 - Pidoto, Ross A1 - Primo, Cristina A1 - Seidel, Jochen A1 - Vorogushyn, Sergiy A1 - Wietzke, Luzie T1 - Causative classification of river flood events JF - Wiley Interdisciplinary Reviews : Water N2 - A wide variety of processes controls the time of occurrence, duration, extent, and severity of river floods. Classifying flood events by their causative processes may assist in enhancing the accuracy of local and regional flood frequency estimates and support the detection and interpretation of any changes in flood occurrence and magnitudes. This paper provides a critical review of existing causative classifications of instrumental and preinstrumental series of flood events, discusses their validity and applications, and identifies opportunities for moving toward more comprehensive approaches. So far no unified definition of causative mechanisms of flood events exists. Existing frameworks for classification of instrumental and preinstrumental series of flood events adopt different perspectives: hydroclimatic (large-scale circulation patterns and atmospheric state at the time of the event), hydrological (catchment scale precipitation patterns and antecedent catchment state), and hydrograph-based (indirectly considering generating mechanisms through their effects on hydrograph characteristics). All of these approaches intend to capture the flood generating mechanisms and are useful for characterizing the flood processes at various spatial and temporal scales. However, uncertainty analyses with respect to indicators, classification methods, and data to assess the robustness of the classification are rarely performed which limits the transferability across different geographic regions. It is argued that more rigorous testing is needed. There are opportunities for extending classification methods to include indicators of space-time dynamics of rainfall, antecedent wetness, and routing effects, which will make the classification schemes even more useful for understanding and estimating floods. This article is categorized under: Science of Water > Water Extremes Science of Water > Hydrological Processes Science of Water > Methods KW - flood genesis KW - flood mechanisms KW - flood typology KW - historical floods KW - hydroclimatology of floods Y1 - 2019 U6 - https://doi.org/10.1002/wat2.1353 SN - 2049-1948 VL - 6 IS - 4 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Kurths, Jürgen A1 - Agarwal, Ankit A1 - Shukla, Roopam A1 - Marwan, Norbert A1 - Maheswaran, Rathinasamy A1 - Caesar, Levke A1 - Krishnan, Raghavan A1 - Merz, Bruno T1 - Unravelling the spatial diversity of Indian precipitation teleconnections via a non-linear multi-scale approach JF - Nonlinear processes in geophysics N2 - A better understanding of precipitation dynamics in the Indian subcontinent is required since India's society depends heavily on reliable monsoon forecasts. We introduce a non-linear, multiscale approach, based on wavelets and event synchronization, for unravelling teleconnection influences on precipitation. We consider those climate patterns with the highest relevance for Indian precipitation. Our results suggest significant influences which are not well captured by only the wavelet coherence analysis, the state-of-the-art method in understanding linkages at multiple timescales. We find substantial variation across India and across timescales. In particular, El Niño–Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD) mainly influence precipitation in the south-east at interannual and decadal scales, respectively, whereas the North Atlantic Oscillation (NAO) has a strong connection to precipitation, particularly in the northern regions. The effect of the Pacific Decadal Oscillation (PDO) stretches across the whole country, whereas the Atlantic Multidecadal Oscillation (AMO) influences precipitation particularly in the central arid and semi-arid regions. The proposed method provides a powerful approach for capturing the dynamics of precipitation and, hence, helps improve precipitation forecasting. Y1 - 2019 U6 - https://doi.org/10.5194/npg-26-251-2019 SN - 1023-5809 SN - 1607-7946 VL - 26 IS - 3 SP - 251 EP - 266 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Agarwal, Ankit A1 - Caesar, Levke A1 - Marwan, Norbert A1 - Maheswaran, Rathinasamy A1 - Merz, Bruno T1 - Network-based identification and characterization of teleconnections on different scales JF - Scientific Reports N2 - Sea surface temperature (SST) patterns can – as surface climate forcing – affect weather and climate at large distances. One example is El Niño-Southern Oscillation (ENSO) that causes climate anomalies around the globe via teleconnections. Although several studies identified and characterized these teleconnections, our understanding of climate processes remains incomplete, since interactions and feedbacks are typically exhibited at unique or multiple temporal and spatial scales. This study characterizes the interactions between the cells of a global SST data set at different temporal and spatial scales using climate networks. These networks are constructed using wavelet multi-scale correlation that investigate the correlation between the SST time series at a range of scales allowing instantaneously deeper insights into the correlation patterns compared to traditional methods like empirical orthogonal functions or classical correlation analysis. This allows us to identify and visualise regions of – at a certain timescale – similarly evolving SSTs and distinguish them from those with long-range teleconnections to other ocean regions. Our findings re-confirm accepted knowledge about known highly linked SST patterns like ENSO and the Pacific Decadal Oscillation, but also suggest new insights into the characteristics and origins of long-range teleconnections like the connection between ENSO and Indian Ocean Dipole. Y1 - 2019 U6 - https://doi.org/10.1038/s41598-019-45423-5 SN - 2045-2322 VL - 9 PB - Macmillan Publishers Limited CY - London ER - TY - JOUR A1 - Barendrecht, Marlies H. A1 - Viglione, Alberto A1 - Kreibich, Heidi A1 - Merz, Bruno A1 - Vorogushyn, Sergiy A1 - Blöschl, G. T1 - The Value of Empirical Data for Estimating the Parameters of a Sociohydrological Flood Risk Model JF - Water resources research N2 - In this paper, empirical data are used to estimate the parameters of a sociohydrological flood risk model. The proposed model, which describes the interactions between floods, settlement density, awareness, preparedness, and flood loss, is based on the literature. Data for the case study of Dresden, Germany, over a period of 200years, are used to estimate the model parameters through Bayesian inference. The credibility bounds of their estimates are small, even though the data are rather uncertain. A sensitivity analysis is performed to examine the value of the different data sources in estimating the model parameters. In general, the estimated parameters are less biased when using data at the end of the modeled period. Data about flood awareness are the most important to correctly estimate the parameters of this model and to correctly model the system dynamics. Using more data for other variables cannot compensate for the absence of awareness data. More generally, the absence of data mostly affects the estimation of the parameters that are directly related to the variable for which data are missing. This paper demonstrates that combining sociohydrological modeling and empirical data gives additional insights into the sociohydrological system, such as quantifying the forgetfulness of the society, which would otherwise not be easily achieved by sociohydrological models without data or by standard statistical analysis of empirical data. Y1 - 2019 U6 - https://doi.org/10.1029/2018WR024128 SN - 0043-1397 SN - 1944-7973 VL - 55 IS - 2 SP - 1312 EP - 1336 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Winter, Benjamin A1 - Schneeberger, Klaus A1 - Dung, N. V. A1 - Huttenlau, M. A1 - Achleitner, S. A1 - Stötter, J. A1 - Merz, Bruno A1 - Vorogushyn, Sergiy T1 - A continuous modelling approach for design flood estimation on sub-daily time scale JF - Hydrological sciences journal = Journal des sciences hydrologiques N2 - Design flood estimation is an essential part of flood risk assessment. Commonly applied are flood frequency analyses and design storm approaches, while the derived flood frequency using continuous simulation has been getting more attention recently. In this study, a continuous hydrological modelling approach on an hourly time scale, driven by a multi-site weather generator in combination with a -nearest neighbour resampling procedure, based on the method of fragments, is applied. The derived 100-year flood estimates in 16 catchments in Vorarlberg (Austria) are compared to (a) the flood frequency analysis based on observed discharges, and (b) a design storm approach. Besides the peak flows, the corresponding runoff volumes are analysed. The spatial dependence structure of the synthetically generated flood peaks is validated against observations. It can be demonstrated that the continuous modelling approach can achieve plausible results and shows a large variability in runoff volume across the flood events. KW - derived flood frequency KW - continuous modelling KW - temporal disaggregation KW - flood hazard KW - synthetic flood events Y1 - 2019 U6 - https://doi.org/10.1080/02626667.2019.1593419 SN - 0262-6667 SN - 2150-3435 VL - 64 IS - 5 SP - 539 EP - 554 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Gerlitz, Lars A1 - Steirou, Eva A1 - Schneider, Christoph A1 - Moron, Vincent A1 - Vorogushyn, Sergiy A1 - Merz, Bruno T1 - Variability of the Cold Season Climate in Central Asia. Part II: Hydroclimatic Predictability JF - Journal of climate N2 - Central Asia (CA) is subjected to a large variability of precipitation. This study presents a statistical model, relating precipitation anomalies in three subregions of CA in the cold season (November-March) with various predictors in the preceding October. Promising forecast skill is achieved for two subregions covering 1) Uzbekistan, Turkmenistan, Kyrgyzstan, Tajikistan, and southern Kazakhstan and 2) Iran, Afghanistan, and Pakistan. ENSO in October is identified as the major predictor. Eurasian snow cover and the quasi-biennial oscillation further improve the forecast performance. To understand the physical mechanisms, an analysis of teleconnections between these predictors and the wintertime circulation over CA is conducted. The correlation analysis of predictors and large-scale circulation indices suggests a seasonal persistence of tropical circulation modes and a dynamical forcing of the westerly circulation by snow cover variations over Eurasia. An EOF analysis of pressure and humidity patterns allows separating the circulation variability over CA into westerly and tropical modes and confirms that the identified predictors affect the respective circulation characteristics. Based on the previously established weather type classification for CA, the predictors are investigated with regard to their effect on the regional circulation. The results suggest a modification of the Hadley cell due to ENSO variations, with enhanced moisture supply from the Arabian Gulf during El Nino. They further indicate an influence of Eurasian snow cover on the wintertime Arctic Oscillation (AO) and Northern Hemispheric Rossby wave tracks. Positive anomalies favor weather types associated with dry conditions, while negative anomalies promote the formation of a quasi-stationary trough over CA, which typically occurs during positive AO conditions. KW - Asia KW - Climate prediction KW - Seasonal forecasting KW - North Atlantic Oscillation KW - Southern Oscillation Y1 - 2019 U6 - https://doi.org/10.1175/JCLI-D-18-0892.1 SN - 0894-8755 SN - 1520-0442 VL - 32 IS - 18 SP - 6015 EP - 6033 PB - American Meteorological Soc. CY - Boston ER - TY - JOUR A1 - Küken, Anika A1 - Nikoloski, Zoran T1 - Computational Approaches to Design and Test Plant Synthetic Metabolic Pathways JF - Plant physiology : an international journal devoted to physiology, biochemistry, cellular and molecular biology, biophysics and environmental biology of plants N2 - Successfully designed and implemented plant-specific synthetic metabolic pathways hold promise to increase crop yield and nutritional value. Advances in synthetic biology have already demonstrated the capacity to design artificial biological pathways whose behavior can be predicted and controlled in microbial systems. However, the transfer of these advances to model plants and crops faces the lack of characterization of plant cellular pathways and increased complexity due to compartmentalization and multicellularity. Modern computational developments provide the means to test the feasibility of plant synthetic metabolic pathways despite gaps in the accumulated knowledge of plant metabolism. Here, we provide a succinct systematic review of optimization-based and retrobiosynthesis approaches that can be used to design and in silico test synthetic metabolic pathways in large-scale plant context-specific metabolic models. In addition, by surveying the existing case studies, we highlight the challenges that these approaches face when applied to plants. Emphasis is placed on understanding the effect that metabolic designs can have on native metabolism, particularly with respect to metabolite concentrations and thermodynamics of biochemical reactions. In addition, we discuss the computational developments that may help to transform the identified challenges into opportunities for plant synthetic biology. Y1 - 2019 U6 - https://doi.org/10.1104/pp.18.01273 SN - 0032-0889 SN - 1532-2548 VL - 179 IS - 3 SP - 894 EP - 906 PB - American Society of Plant Physiologists CY - Rockville ER - TY - JOUR A1 - Schlosser, Rainer A1 - Richly, Keven T1 - Dynamic pricing under competition with data-driven price anticipations and endogenous reference price effects JF - Journal of revenue and pricing management N2 - Online markets have become highly dynamic and competitive. Many sellers use automated data-driven strategies to estimate demand and to update prices frequently. Further, notification services offered by marketplaces allow to continuously track markets and to react to competitors’ price adjustments instantaneously. To derive successful automated repricing strategies is challenging as competitors’ strategies are typically not known. In this paper, we analyze automated repricing strategies with data-driven price anticipations under duopoly competition. In addition, we account for reference price effects in demand, which are affected by the price adjustments of both competitors. We show how to derive optimized self-adaptive pricing strategies that anticipate price reactions of the competitor and take the evolution of the reference price into account. We verify that the results of our adaptive learning strategy tend to optimal solutions, which can be derived for scenarios with full information. Finally, we analyze the case in which our learning strategy is played against itself. We find that our self-adaptive strategies can be used to approximate equilibria in mixed strategies. KW - Dynamic pricing competition KW - Data-driven price anticipation KW - e-Commerce KW - Dynamic programming KW - Response strategies Y1 - 2019 U6 - https://doi.org/10.1057/s41272-019-00206-5 SN - 1476-6930 SN - 1477-657X VL - 18 IS - 6 SP - 451 EP - 464 PB - Palgrave Macmillan CY - Basingstoke ER - TY - JOUR A1 - Ripoll, Jean-Francois A1 - Loridan, Vivien A1 - Denton, Michael H. A1 - Cunningham, Gregory A1 - Reeves, G. A1 - Santolik, O. A1 - Fennell, Joseph A1 - Turner, Drew L. A1 - Drozdov, Alexander A1 - Cervantes Villa, Juan Sebastian A1 - Shprits, Yuri A1 - Thaller, Scott A. A1 - Kurth, William S. A1 - Kletzing, Craig A. A1 - Henderson, Michael G. A1 - Ukhorskiy, Aleksandr Y. T1 - Observations and Fokker-Planck Simulations of the L-Shell, Energy, and Times JF - Journal of geophysical research : Space physics N2 - The evolution of the radiation belts in L-shell (L), energy (E), and equatorial pitch angle (alpha(0)) is analyzed during the calm 11-day interval (4-15 March) following the 1 March 2013 storm. Magnetic Electron and Ion Spectrometer (MagEIS) observations from Van Allen Probes are interpreted alongside 1D and 3D Fokker-Planck simulations combined with consistent event-driven scattering modeling from whistler mode hiss waves. Three (L, E, alpha(0)) regions persist through 11 days of hiss wave scattering; the pitch angle-dependent inner belt core (L similar to <2.2 and E < 700 keV), pitch angle homogeneous outer belt low-energy core (L > similar to 5 and E similar to < 100 keV), and a distinct pocket of electrons (L similar to [4.5, 5.5] and E similar to [0.7, 2] MeV). The pitch angle homogeneous outer belt is explained by the diffusion coefficients that are roughly constant for alpha(0) similar to <60 degrees, E > 100 keV, 3.5 < L < L-pp similar to 6. Thus, observed unidirectional flux decays can be used to estimate local pitch angle diffusion rates in that region. Top-hat distributions are computed and observed at L similar to 3-3.5 and E = 100-300 keV. KW - radiation belts KW - wave-particle interactions KW - electron lifetime KW - pitch angle diffusion coefficient KW - hiss waves Y1 - 2018 U6 - https://doi.org/10.1029/2018JA026111 SN - 2169-9380 SN - 2169-9402 VL - 124 IS - 2 SP - 1125 EP - 1142 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Aseev, Nikita A1 - Shprits, Yuri A1 - Wang, Dedong A1 - Wygant, John A1 - Drozdov, Alexander A1 - Kellerman, Adam C. A1 - Reeves, Geoffrey D. T1 - Transport and loss of ring current electrons inside geosynchronous orbit during the 17 March 2013 storm JF - Journal of geophysical research : Space physics N2 - Ring current electrons (1–100 keV) have received significant attention in recent decades, but many questions regarding their major transport and loss mechanisms remain open. In this study, we use the four‐dimensional Versatile Electron Radiation Belt code to model the enhancement of phase space density that occurred during the 17 March 2013 storm. Our model includes global convection, radial diffusion, and scattering into the Earth's atmosphere driven by whistler‐mode hiss and chorus waves. We study the sensitivity of the model to the boundary conditions, global electric field, the electric field associated with subauroral polarization streams, electron loss rates, and radial diffusion coefficients. The results of the code are almost insensitive to the model parameters above 4.5 RERE, which indicates that the general dynamics of the electrons between 4.5 RE and the geostationary orbit can be explained by global convection. We found that the major discrepancies between the model and data can stem from the inaccurate electric field model and uncertainties in lifetimes. We show that additional mechanisms that are responsible for radial transport are required to explain the dynamics of ≥40‐keV electrons, and the inclusion of the radial diffusion rates that are typically assumed in radiation belt studies leads to a better agreement with the data. The overall effect of subauroral polarization streams on the electron phase space density profiles seems to be smaller than the uncertainties in other input parameters. This study is an initial step toward understanding the dynamics of these particles inside the geostationary orbit. KW - ring current electrons KW - magnetospheric convection KW - ensemble modeling KW - inner magnetosphere KW - electron transport KW - wave-particle interactions Y1 - 2019 U6 - https://doi.org/10.1029/2018JA026031 SN - 2169-9380 SN - 2169-9402 VL - 124 IS - 2 SP - 915 EP - 933 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Wang, Dedong A1 - Shprits, Yuri A1 - Zhelayskaya, Irina S. A1 - Agapitov, Oleksiy A1 - Drozdov, Alexander A1 - Aseev, Nikita T1 - Analytical chorus wave model derived from van Allen Probe Observations JF - Journal of geophysical research : Space physics N2 - Chorus waves play an important role in the dynamic evolution of energetic electrons in the Earth's radiation belts and ring current. Using more than 5 years of Van Allen Probe data, we developed a new analytical model for upper‐band chorus (UBC; 0.5fce < f < fce) and lower‐band chorus (LBC; 0.05fce < f < 0.5fce) waves, where fce is the equatorial electron gyrofrequency. By applying polynomial fits to chorus wave root mean square amplitudes, we developed regression models for LBC and UBC as a function of geomagnetic activity (Kp), L, magnetic latitude (λ), and magnetic local time (MLT). Dependence on Kp is separated from the dependence on λ, L, and MLT as Kp‐scaling law to simplify the calculation of diffusion coefficients and inclusion into particle tracing codes. Frequency models for UBC and LBC are also developed, which depends on MLT and magnetic latitude. This empirical model is valid in all MLTs, magnetic latitude up to 20°, Kp ≤ 6, L‐shell range from 3.5 to 6 for LBC and from 4 to 6 for UBC. The dependence of root mean square amplitudes on L are different for different bands, which implies different energy sources for different wave bands. This analytical chorus wave model is convenient for inclusion in quasi‐linear diffusion calculations of electron scattering rates and particle simulations in the inner magnetosphere, especially for the newly developed four‐dimensional codes, which require significantly improved wave parameterizations. KW - chorus waves KW - radiation belt electrons KW - ring current electrons KW - analytical model KW - wave-particle interactions KW - diffusion coefficients Y1 - 2019 U6 - https://doi.org/10.1029/2018JA026183 SN - 2169-9380 SN - 2169-9402 VL - 124 IS - 2 SP - 1063 EP - 1084 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Aseev, Nikita A1 - Shprits, Yuri T1 - Reanalysis of ring current electron phase space densities using van allen probe observations, convection model, and log‐normal kalman filter JF - Space weather : the international journal of research and applications N2 - Models of ring current electron dynamics unavoidably contain uncertainties in boundary conditions, electric and magnetic fields, electron scattering rates, and plasmapause location. Model errors can accumulate with time and result in significant deviations of model predictions from observations. Data assimilation offers useful tools which can combine physics-based models and measurements to improve model predictions. In this study, we systematically analyze performance of the Kalman filter applied to a log-transformed convection model of ring current electrons and Van Allen Probe data. We consider long-term dynamics of mu = 2.3 MeV/G and K = 0.3 G(1/2) R-E electrons from 1 February 2013 to 16 June 2013. By using synthetic data, we show that the Kalman filter is capable of correcting errors in model predictions associated with uncertainties in electron lifetimes, boundary conditions, and convection electric fields. We demonstrate that reanalysis retains features which cannot be fully reproduced by the convection model such as storm-time earthward propagation of the electrons down to 2.5 R-E. The Kalman filter can adjust model predictions to satellite measurements even in regions where data are not available. We show that the Kalman filter can adjust model predictions in accordance with observations for mu = 0.1, 2.3, and 9.9 MeV/G and constant K = 0.3 G(1/2) R-E electrons. The results of this study demonstrate that data assimilation can improve performance of ring current models, better quantify model uncertainties, and help deeper understand the physics of the ring current particles. Y1 - 2019 U6 - https://doi.org/10.1029/2018SW002110 SN - 1542-7390 VL - 17 IS - 4 SP - 619 EP - 638 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Smirnov, Artem G. A1 - Kronberg, Elena A. A1 - Latallerie, F. A1 - Daly, Patrick W. A1 - Aseev, Nikita A1 - Shprits, Yuri A1 - Kellerman, Adam C. A1 - Kasahara, Satoshi A1 - Turner, Drew L. A1 - Taylor, M. G. G. T. T1 - Electron Intensity Measurements by the Cluster/RAPID/IES Instrument in Earth's Radiation Belts and Ring Current JF - Space Weather: The International Journal of Research and Applications N2 - Plain Language Summary Radiation belts of the Earth, which are the zones of charged energetic particles trapped by the geomagnetic field, comprise enormous and dynamic systems. While the inner radiation belt, composed mainly of high-energy protons, is relatively stable, the outer belt, filled with energetic electrons, is highly variable and depends substantially on solar activity. Hence, extended reliable observations and the improved models of the electron intensities in the outer belt depending on solar wind parameters are necessary for prediction of their dynamics. The Cluster mission has been measuring electron flux intensities in the radiation belts since its launch in 2000, thus providing a huge dataset that can be used for radiation belts analysis. Using 16 years of electron measurements by the Cluster mission corrected for background contamination, we derived a uniform linear-logarithmic dependence of electron fluxes in the outer belt on the solar wind dynamic pressure. Y1 - 2019 U6 - https://doi.org/10.1029/2018SW001989 SN - 1542-7390 VL - 17 IS - 4 SP - 553 EP - 566 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Dobynde, M. I. A1 - Effenberger, Frederic A1 - Kartashov, D. A. A1 - Shprits, Yuri A1 - Shurshakov, V. A. T1 - Ray-tracing simulation of the radiation dose distribution on the surface of the spherical phantom of the MATROSHKA-R experiment onboard the ISS JF - Life sciences in space research N2 - Space radiation is one of the main concerns for human space flights. The prediction of the radiation dose for the actual spacecraft geometry is very important for the planning of long-duration missions. We present a numerical method for the fast calculation of the radiation dose rate during a space flight. We demonstrate its application for dose calculations during the first and the second sessions of the MATROSHKA-R space experiment with a spherical tissue-equivalent phantom. The main advantage of the method is the short simulation time, so it can be applied for urgent radiation dose calculations for low-Earth orbit space missions. The method uses depth-dose curve and shield-and-composition distribution functions to calculate a radiation dose at the point of interest. The spacecraft geometry is processed into a shield-and-composition distribution function using a ray-tracing method. Depth-dose curves are calculated using the GEANT4 Monte-Carlo code (version 10.00.P02) for a double-layer aluminum-water shielding. Aluminum-water shielding is a good approximation of the real geometry, as water is a good equivalent for biological tissues, and aluminum is the major material of spacecraft bodies. KW - Space radiation KW - Radiation protection KW - Radiation dose calculation KW - GEANT4 modeling KW - Radiation on the ISS KW - MATROSHKA-R Y1 - 2019 U6 - https://doi.org/10.1016/j.lssr.2019.04.001 SN - 2214-5524 SN - 2214-5532 VL - 21 SP - 65 EP - 72 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Zhu, Hui A1 - Chen, Lunjin A1 - Liu, Xu A1 - Shprits, Yuri T1 - Modulation of locally generated equatorial noise by ULF wave JF - Journal of geophysical research : Space physics N2 - In this paper we report a rare and fortunate event of fast magnetosonic (MS, also called equatorial noise) waves modulated by compressional ultralow frequency (ULF) waves measured by Van Allen Probes. The characteristics of MS waves, ULF waves, proton distribution, and their potential correlations are analyzed. The results show that ULF waves can modulate the energetic ring proton distribution and in turn modulate the MS generation. Furthermore, the variation of MS intensities is attributed to not only ULF wave activities but also the variation of background parameters, for example, number density. The results confirm the opinion that MS waves are generated by proton ring distribution and propose a new modulation phenomenon. Y1 - 2019 U6 - https://doi.org/10.1029/2018JA026199 SN - 2169-9380 SN - 2169-9402 VL - 124 IS - 4 SP - 2779 EP - 2787 PB - American Geophysical Union CY - Washington ER -