TY - RPRT A1 - Müller, Jörg A1 - Scherer-Lorenzen, Michael A1 - Ammer, Christian A1 - Eisenhauer, Nico A1 - Seidel, Dominik A1 - Schuldt, Bernhard A1 - Biedermann, Peter A1 - Schmitt, Thomas A1 - Künzer, Claudia A1 - Wegmann, Martin A1 - Cesarz, Simone A1 - Peters, Marcell A1 - Feldhaar, Heike A1 - Steffan-Dewenter, Ingolf A1 - Claßen, Alice A1 - Bässler, Claus A1 - von Oheimb, Goddert A1 - Fichtner, Andreas A1 - Thorn, Simon A1 - Weisser, Wolfgang T1 - BETA-FOR: Erhöhung der strukturellen Diversität zwischen Waldbeständen zur Erhöhung der Multidiversität und Multifunktionalität in Produktionswäldern. Antragstext für die DFG Forschungsgruppe FOR 5375 T1 - BETA-FOR: Enhancing the structural diversity between patches for improving multidiversity and multifunctionality in production forests. Proposal for DFG Research Unit FOR 5375 BT - β\(_4\) : Proposal for the 1st phase (2022-2026) of the DFG Research Unit FOR 5375/1 (DFG Forschergruppe FOR 5375/1 – BETA-FOR), Fabrikschleichach, October 2021 N2 - Der in jüngster Zeit beobachtete kontinuierliche Verlust der β-Diversität in Ökosystemen deutet auf homogene Gemeinschaften auf Landschaftsebene hin, was hauptsächlich auf die steigende Landnutzungsintensität zurückgeführt wird. Biologische Vielfalt ist mit zahlreichen Funktionen und der Stabilität von Ökosystemen verknüpft. Es ist daher zu erwarten, dass eine abnehmende β-Diversität auch die Multifunktionalität verringert. Wir kombinieren hier Fachwissen aus der Forstwissenschaft, der Ökologie, der Fernerkundung, der chemischen Ökologie und der Statistik in einem gemeinschaftlichen und experimentellen β-Diversitätsdesign, um einerseits die Auswirkungen der Homogenisierung zu bewerten und andererseits Konzepte zu entwickeln, um negative Auswirkungen durch Homogenisierung in Wäldern rückgängig zu machen. Konkret werden wir uns mit der Frage beschäftigen, ob die Verbesserung der strukturellen β-Komplexität (ESBC) in Wäldern durch Waldbau oder natürliche Störungen die Biodiversität und Multifunktionalität in ehemals homogenen Produktionswäldern erhöhen kann. Unser Ansatz wird mögliche Mechanismen hinter den beobachteten Homogenisierungs-Diversitäts-Beziehungen identifizieren und zeigen, wie sich diese auf die Multifunktionalität auswirken. An elf Standorten in ganz Deutschland haben wir dazu zwei Waldbestände als zwei kleine "Waldlandschaften" ausgewählt. In einem dieser beiden Bestände haben wir ESBC (Enhancement of Structural Beta Complexity)-Behandlungen durchgeführt. Im zweiten, dem Kontrollbestand, werden wir die gleich Anzahl 50x50m Parzellen ohne ESBC einrichten. Auf allen Parzellen werden wir 18 taxonomische Artengruppen aller trophischer Ebenen und 21 Ökosystemfunktionen, einschließlich der wichtigsten Funktionen in Wäldern der gemäßigten Zonen, messen. Der statistische Rahmen wird eine umfassende Analyse der Biodiversität ermöglichen, indem verschiedenen Aspekte (taxonomische, funktionelle und phylogenetische Vielfalt) auf verschiedenen Skalenebenen (α-, β-, γ-Diversität) quantifiziert werden. Um die Gesamtdiversität zu kombinieren, werden wir das Konzept der Multidiversität auf die 18 Taxa anwenden. Wir werden neue Ansätze zur Quantifizierung und Aufteilung der Multifunktionalität auf α- und β-Skalen verwenden und entwickeln. Durch die experimentelle Beschreibung des Zusammenhangs zwischen β-Diversität und Multifunktionalität in einer Reallandschaft wird unsere Forschung einen neuen Weg einschlagen. Darüber hinaus werden wir dazu beitragen, verbesserte Leitlinien für waldbauliche Konzepte und für das Management natürlicher Störungen zu entwickeln, um Homogenisierungseffekte der Vergangenheit umzukehren. N2 - The recently observed consistent loss of β-diversity across ecosystems indicates increasingly homogeneous communities in patches of landscapes, mainly caused by increasing land-use intensity. Biodiversity is related to numerous ecosystem functions and stability. Therefore, decreasing β-diversity is also expected to reduce multifunctionality. To assess the impact of homogenization and to develop guidelines to reverse its potentially negative effects, we combine expertise from forest science, ecology, remote sensing, chemical ecology and statistics in a collaborative and experimental β-diversity approach. Specifically, we will address the question whether the Enhancement of Structural Beta Complexity (ESBC) in forests by silviculture or natural disturbances will increase biodiversity and multifunctionality in formerly homogeneously structured production forests. Our approach will identify potential mechanisms behind observed homogenization-diversity-relationships and show how these translate into effects on multifunctionality. At eleven forest sites throughout Germany, we selected two districts as two types of small ‘forest landscapes’. In one of these two districts, we established ESBC treatments (nine differently treated 50x50 m patches with a focus on canopy cover and deadwood features). In the second, the control district, we will establish nine patches without ESBC. By a comprehensive sampling, we will monitor 18 taxonomic groups and measure 21 ecosystem functions, including key functions in temperate forests, on all patches. The statistical framework will allow a comprehensive biodiversity assessment by quantifying the different aspects of multitrophic biodiversity (taxonomical, functional and phylogenetic diversity) on different levels of biodiversity (α-, β-, γ-diversity). To combine overall diversity, we will apply the concept of multidiversity across the 18 taxa. We will use and develop new approaches for quantification and partitioning of multifunctionality at α- and β- scales. Overall, our study will herald a new research avenue, namely by experimentally describing the link between β-diversity and multifunctionality. Furthermore, we will help to develop guidelines for improved silvicultural concepts and concepts for management of natural disturbances in temperate forests reversing past homogenization effects. KW - Waldökosystem KW - Biodiversität KW - BETA-Multifunktionalität KW - beta-multifunctionality KW - BETA-Diversität KW - beta diversity KW - Forschungsstation Fabrikschleichach Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-290849 ER - TY - JOUR A1 - Buchelt, Sebastian A1 - Skov, Kirstine A1 - Rasmussen, Kerstin Krøier A1 - Ullmann, Tobias T1 - Sentinel-1 time series for mapping snow cover depletion and timing of snowmelt in Arctic periglacial environments: case study from Zackenberg and Kobbefjord, Greenland JF - The Cryosphere N2 - Snow cover (SC) and timing of snowmelt are key regulators of a wide range of Arctic ecosystem functions. Both are strongly influenced by the amplified Arctic warming and essential variables to understand environmental changes and their dynamics. This study evaluates the potential of Sentinel-1 (S-1) synthetic aperture radar (SAR) time series for monitoring SC depletion and snowmelt with high spatiotemporal resolution to capture their understudied small-scale heterogeneity. We use 97 dual-polarized S-1 SAR images acquired over northeastern Greenland and 94 over southwestern Greenland in the interferometric wide swath mode from the years 2017 and 2018. Comparison of S-1 intensity against SC fraction maps derived from orthorectified terrestrial time-lapse imagery indicates that SAR backscatter can increase before a decrease in SC fraction is observed. Hence, the increase in backscatter is related to changing snowpack properties during the runoff phase as well as decreasing SC fraction. We here present a novel empirical approach based on the temporal evolution of the SAR signal to identify start of runoff (SOR), end of snow cover (EOS) and SC extent for each S-1 observation date during melt using backscatter thresholds as well as the derivative. Comparison of SC with orthorectified time-lapse imagery indicates that HV polarization outperforms HH when using a global threshold. The derivative avoids manual selection of thresholds and adapts to different environmental settings and seasonal conditions. With a global configuration (threshold: 4 dB; polarization: HV) as well as with the derivative, the overall accuracy of SC maps was in all cases above 75 % and in more than half of cases above 90 %. Based on the physical principle of SAR backscatter during snowmelt, our approach is expected to work well in other low-vegetation areas and, hence, could support large-scale SC monitoring at high spatiotemporal resolution (20 m, 6 d) with high accuracy. KW - Greenland KW - Sentinel-1 (S-1) synthetic aperture radar (SAR) KW - snow cover depletion Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300139 VL - 16 IS - 2 SP - 625 EP - 646 ER - TY - JOUR A1 - Rauch, Sebastian A1 - Arnold, Louisa A1 - Stuerner, Zelda A1 - Rauh, Juergen A1 - Rost, Michael T1 - A true choice of place of birth? Swiss women’s access to birth hospitals and birth centers JF - PLoS ONE N2 - While the place of birth plays a crucial role for women’s birth experiences, the interest in out-of-hospital births has increased during the Covid-19 pandemic. Related to this, various international policies recommend enabling women to choose where to give birth. We aimed to analyze Swiss women’s choice between birth hospitals and birth centers. Employing spatial accessibility analysis, we incorporated four data types: highly disaggregated population data, administrative data, street network data, addresses of birth hospitals and birth centers. 99.8% of Swiss women of childbearing age were included in the analysis (N = 1.896.669). We modelled car travel times from a woman’s residence to the nearest birth hospital and birth center. If both birth settings were available within 30 minutes, a woman was considered to have a true choice. Only 58.2% of women had a true choice. This proportion varied considerably across Swiss federal states. The main barrier to a true choice was limited accessibility of birth centers. Median travel time to birth hospitals was 9.8 (M = 12.5), to birth centers 23.9 minutes (M = 28.5). Swiss women are insufficiently empowered to exercise their reproductive autonomy as their choice of place of birth is significantly limited by geographical constraints. It is an ethical and medical imperative to provide women with a true choice. We provide high-resolution insights into the accessibility of birth settings and strong arguments to (re-)examine the need for further birth centers (and birth hospitals) in specific geographical areas. Policy-makers are obligated to improve the accessibility of birth centers to advance women’s autonomy and enhance maternal health outcomes after childbirth. The Covid-19 pandemic offers an opportunity to shift policy. KW - Switzerland KW - birth hospitals KW - access Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300159 VL - 17 IS - 7 ER - TY - RPRT A1 - Meyer, Constantin A1 - Job, Hubert A1 - Laner, Peter A1 - Omizzolo, Andrea A1 - Kollmann, Nadia A1 - Clare, Jasmin A1 - Vesely, Philipp A1 - Riedler, Walter A1 - Plassmann, Guido A1 - Coronado, Oriana A1 - Praper Gulič, Sergeja A1 - Gulič, Andrej A1 - Koblar, Simon A1 - Teofili, Corrado A1 - Rohringer, Verena A1 - Schoßleitner, Richard A1 - Ainz, Gerhard T1 - OpenSpaceAlps Planungshandbuch: Perspektiven für eine konsistente Freiraumsicherung im Alpenraum T1 - OpenSpaceAlps Planning Handbook: Perspectives for consistent safeguarding of open spaces in the Alpine region N2 - Im Alpenraum lässt sich nach wie vor die kontinuierliche Inanspruchnahme von Freiräumen für Siedlungsflächen und technische Infrastrukturen und die damit verbundene Bodenversiegelung beobachten. Dies führt in erster Linie zum Verlust von landwirtschaftlichen Flächen. Je nach Ausmaß der Bebauung kommt es auch zu einer verstärkten Landschaftszerschneidung, die zur Isolierung natürlicher Lebensräume und zur Einschränkung des ökologischen Verbundes sowie zu weiteren negativen Folgewirkungen führt. Das OpenSpaceAlps Projekt hat sich dieser Thematik angenommen und, basierend auf kooperativen Verfahren in mehreren Pilotregionen, Handlungsansätze und Strategien für eine nachhaltige Sicherung von Freiräumen entwickelt. Dieses Handbuch stellt eine Handlungs- und Entscheidungshilfe für verschiedene Akteure/Akteurinnen dar, allen voran Planer*innen in öffentlichen Planungsbehörden. Ausgehend von einer Analyse der Herausforderungen und Rahmenbedingungen im Alpenraum, werden in diesem Handbuch zentrale „Prinzipien“ der Freiraumplanung vorgestellt und verglichen. Außerdem werden integrierte Planungsstrategien für verschiedene Raumkategorien diskutiert. KW - Raumordnung KW - Alpen KW - Alpen KW - OpenSpaceAlps KW - Freiraum KW - Raumplanung KW - Transnationale Zusammenarbeit Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-273070 N1 - English version available at: https://doi.org/10.25972/OPUS-27040. Italian version available at: https://doi.org/10.25972/OPUS-27704. N1 - The OpenSpaceAlps project is co-financed by the European Regional Development Fund through the Interreg Alpine Space programme. ER - TY - THES A1 - Wilde, Martina T1 - Landslide susceptibility assessment in the Chiconquiaco Mountain Range area, Veracruz (Mexico) T1 - Bewertung der Rutschungssuszeptibilität in der Chiconquiaco Gebirgsregion, Veracruz (Mexiko) N2 - In Mexico, numerous landslides occur each year and Veracruz represents the state with the third highest number of events. Especially the Chiconquiaco Mountain Range, located in the central part of Veracruz, is highly affected by landslides and no detailed information on the spatial distribution of existing landslides or future occurrences is available. This leaves the local population exposed to an unknown threat and unable to react appropriately to this hazard or to consider the potential landslide occurrence in future planning processes. Thus, the overall objective of the present study is to provide a comprehensive assessment of the landslide situation in the Chiconquiaco Mountain Range area. Here, the combination of a site-specific and a regional approach enables to investigate the causes, triggers, and process types as well as to model the landslide susceptibility for the entire study area. For the site-specific approach, the focus lies on characterizing the Capulín landslide, which represents one of the largest mass movements in the area. In this context, the task is to develop a multi-methodological concept, which concentrates on cost-effective, flexible and non-invasive methods. This approach shows that the applied methods complement each other very well and their combination allows for a detailed characterization of the landslide. The analyses revealed that the Capulín landslide is a complex mass movement type. It comprises rotational movement in the upper parts and translational movement in the lower areas, as well as flow processes at the flank and foot area and therefore, is classified as a compound slide-flow according to Cruden and Varnes (1996). Furthermore, the investigations show that the Capulín landslide represents a reactivation of a former process. This is an important new information, especially with regard to the other landslides identified in the study area. Both the road reconstructed after the landslide, which runs through the landslide mass, and the stream causing erosion processes at the foot of the landslide severely affect the stability of the landslide, making it highly susceptible to future reactivation processes. This is particularly important as the landslide is located only few hundred meters from the village El Capulín and an extension of the landslide area could cause severe damage. The next step in the landslide assessment consists of integrating the data obtained in the site-specific approach into the regional analysis. Here, the focus lies on transferring the generated data to the entire study area. The developed methodological concept yields applicable results, which is supported by different validation approaches. The susceptibility modeling as well as the landslide inventory reveal that the highest probability of landslides occurrence is related to the areas with moderate slopes covered by slope deposits. These slope deposits comprise material from old mass movements and erosion processes and are highly susceptible to landslides. The results give new insights into the landslide situation in the Chiconquiaco Mountain Range area, since previously landslide occurrence was related to steep slopes of basalt and andesite. The susceptibility map is a contribution to a better assessment of the landslide situation in the study area and simultaneously proves that it is crucial to include specific characteristics of the respective area into the modeling process, otherwise it is possible that the local conditions will not be represented correctly. N2 - In Mexico ereignen sich jedes Jahr zahlreiche Rutschungen und Veracruz ist der Bundesstaat mit der dritthöchsten Anzahl von solchen Ereignissen. Besonders das Chiconquiaco Gebirge, welches im zentralen Bereich von Veracruz liegt, ist stark von Rutschungen betroffen und trotzdem sind keine detaillierten Informationen zur räumlichen Verbreitung existierender Rutschungen oder zu deren erwarteten, zukünftigen Auftreten verfügbar. Dadurch ist die lokale Bevölkerung mit einer nicht einschätzbaren Bedrohungslage konfrontiert und kann weder auf diese angemessen reagieren noch das potentielle Auftreten von Rutschungen in künftigen Planungsprozessen berücksichtigen. Das übergeordnete Ziel der vorliegenden Arbeit besteht daher darin, eine umfassende Beurteilung der Rutschungssituation im Chiconquiaco Gebirge zu erstellen. Hierbei ermöglicht die Kombination eines standortspezifischen und eines regionalen Ansatzes sowohl die Untersuchung der Ursachen, Auslöser und Prozesstypen, als auch die Modellierung der Rutschanfälligkeit für das gesamte Untersuchungsgebiet. Bei dem standortspezifischen Ansatz liegt der Schwerpunkt auf der Charakterisierung der Capulín Rutschung, bei der es sich um eine der größten Massenbewegungen in dieser Region handelt. In diesem Rahmen besteht die Aufgabe darin, ein multi-methodologisches Konzept zu entwickeln, welches sich hauptsächlich auf kostengünstige, flexible und nicht-invasive Methoden konzentriert. Dieser Ansatz zeigt, dass sich die verwendeten Methoden sehr gut ergänzen und ihre Kombination eine detaillierte Charakterisierung der Rutschung ermöglicht. Die Ergebnisse legen dar, dass die Capulín Rutschung eine komplexe Massenbewegung ist. So umfasst sie Rotationsbewegungen im oberen und Translationsbewegungen im unteren Bereich, sowie Fließprozesse an der Flanke und im Fußbereich und kann daher nach Cruden und Varnes (1996) als Kombination aus Gleit- und Fließprozessen (compound slide-flow) klassifiziert werden. Des Weiteren zeigen die Ergebnisse, dass es sich bei der Capulín Rutschung um eine Reaktivierung einer älteren Rutschung handelt. Das ist eine wichtige neue Erkenntnis besonders im Hinblick auf die anderen Rutschungen, die im Untersuchungsgebiet festgestellt wurden. Sowohl die nach der Rutschung wieder aufgebaute Straße, die durch die Rutschmasse verläuft, als auch der Fluss, der Erosionsprozesse am Fuß der Rutschung verursacht, beeinträchtigen die Stabilität der Capulín Rutschung maßgeblich, was sie sehr anfällig für zukünftige Reaktivierungsprozesse macht. Dies ist besonders wichtig, da die Rutschung nur wenige hundert Meter von dem Ort El Capulín entfernt ist und eine Erweiterung des Rutschgebietes erhebliche Schäden verursachen könnte. Im Anschluss werden die durch den lokalen Ansatz erhaltenen Daten in die regionale Analyse integriert. Der Fokus bei diesem Vorgehen liegt dabei auf der Übertragung der generierten Daten auf das gesamte Untersuchungsgebiet. Das hier entwickelte methodische Konzept erzielt verwertbare Ergebnisse, was durch verschiedene Validierungsansätze bekräftigt werden kann. Sowohl die Suszeptibilitätsmodellierung als auch das Rutschungsinventar zeigen, dass die höchste Wahrscheinlichkeit für das Auftreten von Rutschungen vor allem in den Gebieten mit moderater Hangneigung liegt, welche mit Hangschutt bedeckt sind. Diese Hangablagerungen bestehen aus Material von alten Massenbewegungen und Erosionsprozessen und zeigen eine hohe Anfälligkeit für Rutschungen. Die Ergebnisse liefern neue Erkenntnisse über die Rutschungssituation im Chiconquiaco Gebirge, da vorher das Auftreten von Rutschungen mit den steilen Hängen aus Basalt und Andesit in Verbindung gebracht wurde. Auf Grundlage der generierten Suszeptibilitätskarte ist eine bessere Bewertung der Rutschungssituation im Untersuchungsgebiet möglich. Weiterhin zeigt sie, dass es von entscheidender Bedeutung ist, spezifische Eigenschaften der jeweiligen Untersuchungsgebiete in die Modellierung miteinzubeziehen, da sonst die Gefahr besteht, dass die örtlichen Gegebenheiten fehlerhaft eingeschätzt werden. KW - Naturgefahren KW - Landslide susceptibility modeling KW - Geomorphologie KW - Rutschungen KW - Modellierung KW - Veracruz KW - Mexiko KW - UAV KW - Digital Elevation Model KW - Hangstabilitätsmodellierung Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-276085 ER - TY - THES A1 - Ibebuchi, Chibuike Chiedozie T1 - Bias correction of climate model output for Germany T1 - Bias-Korrektur des Klimamodell-Outputs für Deutschland N2 - Regional climate models (RCMs) are tools used to project future climate change at a regional scale. Despite their high horizontal resolution, RCMs are characterized by systematic biases relative to observations, which can result in unrealistic interpretations of future climate change signals. On the other hand, bias correction (BC) is a popular statistical post-processing technique applied to improve the usability of output from climate models. Like every other statistical technique, BC has its strengths and weaknesses. Hence, within the regional context of Germany, and for temperature and precipitation, this study is dedicated to the assessment of the impact of different BC techniques on the RCM output. The focuses are on the impact of BC on the RCM’s statistical characterization, and physical consistency defined as the spatiotemporal consistency between the bias-corrected variable and the simulated physical mechanisms governing the variable, as well as the correlations between the bias-corrected variable and other (simulated) climate variables. Five BC techniques were applied in adjusting the systematic biases in temperature and precipitation RCM outputs. The BC techniques are linear scaling, empirical quantile mapping, univariate quantile delta mapping, multivariate quantile delta mapping that considers inter-site dependencies, and multivariate quantile delta mapping that considers inter-variable dependencies (MBCn). The results show that each BC technique adds value in reducing the biases in the statistics of the RCM output, though the added value depends on several factors such as the temporal resolution of the data, choice of RCM, climate variable, region, and the metric used in evaluating the BC technique. Further, the raw RCMs reproduced portions of the observed modes of atmospheric circulation in Western Europe, and the observed temperature, and precipitation meteorological patterns in Germany. After the BC, generally, the spatiotemporal configurations of the simulated meteorological patterns as well as the governing large-scale mechanisms were reproduced. However, at a more localized spatial scale for the individual meteorological patterns, the BC changed the simulated co-variability of some grids, especially for precipitation. Concerning the co-variability among the variables, a physically interpretable positive correlation was found between temperature and precipitation during boreal winter in both models and observations. For most grid boxes in the study domain and on average, the BC techniques that do not adjust inter-variable dependency did not notably change the simulated correlations between the climate variables. However, depending on the grid box, the (univariate) BC techniques tend to degrade the simulated temporal correlations between temperature and precipitation. Further, MBCn which adjusts biases in inter-variable dependency has the skill to improve the correlations between the simulated variables towards observations. N2 - Regionale Klimamodelle (RCMs) sind Werkzeuge, die verwendet werden, um den zukünftigen Klimawandel auf regionaler Ebene zu prognostizieren. Trotz ihrer hohen horizontalen Auflösung sind RCMs je nach Beobachtung durch systematische Verzerrungen gekennzeichnet, was zu unrealistischen Interpretationen zukünftiger Signale des Klimawandels führen kann. Andererseits ist die Bias-Korrektur (BC) eine beliebte statistische Nachbearbeitungstechnik, die angewendet wird, um die Nutzbarkeit der Ergebnisse von Klimamodellen zu verbessern. Wie jede andere statistische Technik hat BC seine Stärken und Schwächen. Daher widmet sich diese Studie im regionalen Kontext Deutschlands und für Temperatur und Niederschlag der Bewertung der Auswirkungen verschiedener BC-Techniken auf den das RCM-ErtragErgebnis. Die Schwerpunkte liegen auf der Auswirkung von BC auf die statistische Charakterisierung des RCM und auf der physikalischen Konsistenz. Letztere ist, definiert als die räumlich-zeitliche Konsistenz zwischen der systematisch korrigierten Variablen und den simulierten physikalischen Mechanismen, die diese Variable steuern, sowie auf den Korrelationen zwischen der systematisch korrigierten Variablen und anderen (simulierten) Klimavariablen. Fünf BC-Techniken wurden angewendet, um die systematischen Abweichungen in den Temperatur- und Niederschlags-RCM-Ausgaben Ergebnissen anzupassen. Die BC-Techniken sind lineare Skalierung, empirisches Quantil-Mapping, univariates Quantil-Delta-Mapping, sowie multivariates Quantil-Delta-Mapping, das Abhängigkeiten zwischen Standorten berücksichtigt, und multivariates Quantil-Delta-Mapping, das intervariable Abhängigkeiten (MBCn) berücksichtigt. Die Ergebnisse zeigen, dass jede BC-Technik einen Mehrwert bei der Reduzierung der Verzerrungen in den Statistiken der RCM-Ausgabe bringt, und dies, obwohl der Mehrwert von mehreren Faktoren abhängt, wie der zeitlichen Auflösung der Daten, der Wahl der RCM, der Klimavariable, der Region und desr verwendeten Massstabsetrik zur Bewertung der BC-Technik verwendet. Darüber hinaus reproduzierten die rohen RCMs Teile der beobachteten Modi der atmosphärischen Zirkulation in Westeuropa und die beobachteten meteorologischen Temperatur- und Niederschlagsmuster in Deutschland. Nach der BC wurden im Allgemeinen die raumzeitlichen Konfigurationen der simulierten meteorologischen Muster sowie die maßgeblichen großräumigen Mechanismen reproduziert. Auf einer stärker lokalisierten räumlichen Skala änderte der BC jedoch für die einzelnen meteorologischen Muster die simulierte Kovariabilität einiger Gitter, insbesondere für Niederschlag. Bezüglich der Kovariabilität zwischen den Variablen wurde sowohl in Modellen als auch in Beobachtungen eine physikalisch interpretierbare positive Korrelation zwischen Temperatur und Niederschlag im borealen Winter gefunden. Für die meisten Gitterboxen Gitterfelder im Untersuchungsbereich und auch im Durchschnitt änderten die BC-Techniken, die die Abhängigkeit zwischen den Variablen nicht anpassen, die simulierten Korrelationen zwischen den Klimavariablen nicht merklich. Allerdings neigen die (univariaten) BC-Techniken je nach Gitterbox Gitterfeld dazu, die simulierten zeitlichen Korrelationen zwischen Temperatur und Niederschlag zu verschlechtern. Darüber hinaus hat MBCn, das Verzerrungen in der Abhängigkeit zwischen Variablen anpasst, die Fähigkeit, die Korrelationen zwischen den simulierten Variablen gegenüber den Beobachtungen zu verbessern. KW - Bias correction KW - regional climate models KW - Germany KW - physical consistency KW - meteorological patterns KW - Bias-Korrektur KW - Regionale Klimamodelle KW - Deutschland KW - Physikalische Konsistenz KW - Meteorologische Muster Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-312647 ER - TY - JOUR A1 - Ibebuchi, Chibuike Chiedozie A1 - Schönbein, Daniel A1 - Adakudlu, Muralidhar A1 - Xoplaki, Elena A1 - Paeth, Heiko T1 - Comparison of three techniques to adjust daily precipitation biases from regional climate models over Germany JF - Water N2 - This study compares the performance of three bias correction (BC) techniques in adjusting simulated precipitation estimates over Germany. The BC techniques are the multivariate quantile delta mapping (MQDM) where the grids are used as variables to incorporate the spatial dependency structure of precipitation in the bias correction; empirical quantile mapping (EQM) and, the linear scaling (LS) approach. Several metrics that include first to fourth moments and extremes characterized by the frequency of heavy wet days and return periods during boreal summer were applied to score the performance of the BC techniques. Our results indicate a strong dependency of the relative performances of the BC techniques on the choice of the regional climate model (RCM), the region, the season, and the metrics of interest. Hence, each BC technique has relative strengths and weaknesses. The LS approach performs well in adjusting the first moment but tends to fall short for higher moments and extreme precipitation during boreal summer. Depending on the season, the region and the RCM considered, there is a trade-off between the relative performances of the EQM and the MQDM in adjusting the simulated precipitation biases. However, the MQDM performs well across all considered metrics. Overall, the MQDM outperforms the EQM in improving the higher moments and in capturing the observed return level of extreme summer precipitation, averaged over Germany. KW - bias correction KW - multivariate quantile delta mapping KW - empirical quantile mapping KW - linear scaling KW - precipitation KW - Germany Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-262064 SN - 2073-4441 VL - 14 IS - 4 ER - TY - JOUR A1 - Nyamekye, Clement A1 - Thiel, Michael A1 - Schönbrodt-Stitt, Sarah A1 - Zoungrana, Benewinde J.-B. A1 - Amekudzi, Leonard K. T1 - Soil and water conservation in Burkina Faso, West Africa JF - Sustainability N2 - Inadequate land management and agricultural activities have largely resulted in land degradation in Burkina Faso. The nationwide governmental and institutional driven implementation and adoption of soil and water conservation measures (SWCM) since the early 1960s, however, is expected to successively slow down the degradation process and to increase the agricultural output. Even though relevant measures have been taken, only a few studies have been conducted to quantify their effect, for instance, on soil erosion and environmental restoration. In addition, a comprehensive summary of initiatives, implementation strategies, and eventually region-specific requirements for adopting different SWCM is missing. The present study therefore aims to review the different SWCM in Burkina Faso and implementation programs, as well as to provide information on their effects on environmental restoration and agricultural productivity. This was achieved by considering over 143 studies focusing on Burkina Faso’s experience and research progress in areas of SWCM and soil erosion. SWCM in Burkina Faso have largely resulted in an increase in agricultural productivity and improvement in food security. Finally, this study aims at supporting the country’s informed decision-making for extending already existing SWCM and for deriving further implementation strategies. KW - soil and water conservation KW - environmental degradation KW - agricultural productivity KW - food security KW - soil erosion KW - Burkina Faso Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-197653 SN - 2071-1050 VL - 10 IS - 9 ER - TY - JOUR A1 - Steininger, Michael A1 - Abel, Daniel A1 - Ziegler, Katrin A1 - Krause, Anna A1 - Paeth, Heiko A1 - Hotho, Andreas T1 - ConvMOS: climate model output statistics with deep learning JF - Data Mining and Knowledge Discovery N2 - Climate models are the tool of choice for scientists researching climate change. Like all models they suffer from errors, particularly systematic and location-specific representation errors. One way to reduce these errors is model output statistics (MOS) where the model output is fitted to observational data with machine learning. In this work, we assess the use of convolutional Deep Learning climate MOS approaches and present the ConvMOS architecture which is specifically designed based on the observation that there are systematic and location-specific errors in the precipitation estimates of climate models. We apply ConvMOS models to the simulated precipitation of the regional climate model REMO, showing that a combination of per-location model parameters for reducing location-specific errors and global model parameters for reducing systematic errors is indeed beneficial for MOS performance. We find that ConvMOS models can reduce errors considerably and perform significantly better than three commonly used MOS approaches and plain ResNet and U-Net models in most cases. Our results show that non-linear MOS models underestimate the number of extreme precipitation events, which we alleviate by training models specialized towards extreme precipitation events with the imbalanced regression method DenseLoss. While we consider climate MOS, we argue that aspects of ConvMOS may also be beneficial in other domains with geospatial data, such as air pollution modeling or weather forecasts. KW - Klima KW - Modell KW - Deep learning KW - Neuronales Netz KW - climate KW - neural networks KW - model output statistics Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324213 SN - 1384-5810 VL - 37 IS - 1 ER - TY - JOUR A1 - Ibebuchi, Chibuike Chiedozie A1 - Schönbein, Daniel A1 - Paeth, Heiko T1 - On the added value of statistical post-processing of regional climate models to identify homogeneous patterns of summer rainfall anomalies in Germany JF - Climate Dynamics N2 - A fuzzy classification scheme that results in physically interpretable meteorological patterns associated with rainfall generation is applied to classify homogeneous regions of boreal summer rainfall anomalies in Germany. Four leading homogeneous regions are classified, representing the western, southeastern, eastern, and northern/northwestern parts of Germany with some overlap in the central parts of Germany. Variations of the sea level pressure gradient across Europe, e.g., between the continental and maritime regions, is the major phenomenon that triggers the time development of the rainfall regions by modulating wind patterns and moisture advection. Two regional climate models (REMO and CCLM4) were used to investigate the capability of climate models to reproduce the observed summer rainfall regions. Both regional climate models (RCMs) were once driven by the ERA-Interim reanalysis and once by the MPI-ESM general circulation model (GCM). Overall, the RCMs exhibit good performance in terms of the regionalization of summer rainfall in Germany; though the goodness-of-match with the rainfall regions/patterns from observational data is low in some cases and the REMO model driven by MPI-ESM fails to reproduce the western homogeneous rainfall region. Under future climate change, virtually the same leading modes of summer rainfall occur, suggesting that the basic synoptic processes associated with the regional patterns remain the same over Germany. We have also assessed the added value of bias-correcting the MPI-ESM driven RCMs using a simple linear scaling approach. The bias correction does not significantly alter the identification of homogeneous rainfall regions and, hence, does not improve their goodness-of-match compared to the observed patterns, except for the one case where the original RCM output completely fails to reproduce the observed pattern. While the linear scaling method improves the basic statistics of precipitation, it does not improve the simulated meteorological patterns represented by the precipitation regimes. KW - summer precipitation regions KW - Germany KW - climate models KW - fuzzy classification KW - bias correction Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324122 SN - 0930-7575 VL - 59 IS - 9-10 ER - TY - JOUR A1 - Geyer, Gerd A1 - Landing, Ed A1 - Meier, Stefan A1 - Höhn, Stefan T1 - Oldest known West Gondwanan graptolite: Ovetograptus? sp. (lower Agdzian/lowest Wuliuan; basal Middle Cambrian) of the Franconian Forest, Germany, and review of pre-Furongian graptolithoids JF - Paläontologische Zeitschrift N2 - The occurrence of a likely graptolite in lowest Wuliuan strata of the Franconian Forest almost certainly records the oldest known graptolithoid hemichordate in West Gondwana and possibly the oldest graptolite presently known. The fossil is a delicate, erect, apparently unbranched rhabdosome with narrow thecae tentatively assigned to the poorly known genus Ovetograptus of the Dithecodendridae. This report includes an overview of pre-Furongian graptolithoids with slight corrections on the stratigraphic position of earlier reported species. KW - Cambrian KW - Graptolithoidea KW - biostratigraphy KW - morphology KW - West Gondwana Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324099 SN - 0031-0220 VL - 97 IS - 4 ER - TY - JOUR A1 - Rai, P. A1 - Ziegler, K. A1 - Abel, D. A1 - Pollinger, F. A1 - Paeth, H. T1 - Performance of a regional climate model with interactive vegetation (REMO-iMOVE) over Central Asia JF - Theoretical and Applied Climatology N2 - The current study evaluates the regional climate model REMO (v2015) and its new version REMO-iMOVE, including interactive vegetation and plant functional types (PFTs), over two Central Asian domains for the period of 2000–2015 at two different horizontal resolutions (0.44° and 0.11°). Various statistical metrices along with mean bias patterns for precipitation, temperature, and leaf area index have been used for the model evaluation. A better representation of the spatial pattern of precipitation is found at 0.11° resolution over most of Central Asia. Regarding the mean temperature, both model versions show a high level of agreement with the validation data, especially at the higher resolution. This also reduces the biases in maximum and minimum temperature. Generally, REMO-iMOVE shows an improvement regarding the temperature bias but produces a larger precipitation bias compared to the REMO conventional version with interannually static vegetation. Since the coupled version is capable to simulate the mean climate of Central Asia like its parent version, both can be used for impact studies and future projections. However, regarding the new vegetation scheme and its spatiotemporal representation exemplified by the leaf area index, REMO-iMOVE shows a clear advantage over REMO. This better simulation is caused by the implementation of more realistic and interactive vegetation and related atmospheric processes which consequently add value to the regional climate model. KW - regional climate model (RCM) KW - interactive vegetation KW - REMO-iMOVE KW - Central Asia KW - evaluation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324155 SN - 0177-798X VL - 150 IS - 3-4 ER - TY - JOUR A1 - Libanda, Brigadier T1 - Performance assessment of CORDEX regional climate models in wind speed simulations over Zambia JF - Modeling Earth Systems and Environment N2 - There is no single solution to cutting emissions, however, renewable energy projects that are backed by rigorous ex-ante assessments play an important role in these efforts. An inspection of literature reveals critical knowledge gaps in the understanding of future wind speed variability across Zambia, thus leading to major uncertainties in the understanding of renewable wind energy potential over the country. Several model performance metrics, both statistical and graphical were used in this study to examine the performance of CORDEX Africa Regional Climate Models (RCMs) in simulating wind speed across Zambia. Results indicate that wind speed is increasing at the rate of 0.006 m s\(^{−1}\) per year. RCA4-GFDL-ESM2M, RCA4-HadGEM2-ES, RCA4-IPSL-CM5A-MR, and RCA4-CSIRO-MK3.6.0 were found to correctly simulate wind speed increase with varying magnitudes on the Sen’s estimator of slope. All the models sufficiently reproduce the annual cycle of wind speed with a steady increase being observed from April reaching its peak around August/September and beginning to drop in October. Apart from RegCM4-MPI-ESM and RegCM4-HadGEM2, the performance of RCMs in simulating spatial wind speed patterns is generally good although they overestimate it by ~ 1 m s\(^{−1}\) in the western and southern provinces of the country. Model performance metrics indicate that with a correlation coefficient of 0.5, a root mean square error of 0.4 m s\(^{−1}\), an RSR value of 7.7 and a bias of 19.9%, RCA4-GFDL-ESM2M outperforms all other models followed by RCA4-HadGEM2, and RCA4-CM5A-MR respectively. These results, therefore, suggest that studies that use an ensemble of RCA4-GFDL-ESM2M, RCA4-HadGEM2, and RCA4-CM5A-MR would yield useful results for informing future renewable wind energy potential in Zambia. KW - renewable energy KW - wind speed KW - CORDEX Africa KW - Zambia Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324147 SN - 2363-6203 VL - 9 IS - 1 ER - TY - JOUR A1 - Kanmegne Tamga, Dan A1 - Latifi, Hooman A1 - Ullmann, Tobias A1 - Baumhauer, Roland A1 - Thiel, Michael A1 - Bayala, Jules T1 - Modelling the spatial distribution of the classification error of remote sensing data in cocoa agroforestry systems JF - Agroforestry Systems N2 - Cocoa growing is one of the main activities in humid West Africa, which is mainly grown in pure stands. It is the main driver of deforestation and encroachment in protected areas. Cocoa agroforestry systems which have been promoted to mitigate deforestation, needs to be accurately delineated to support a valid monitoring system. Therefore, the aim of this research is to model the spatial distribution of uncertainties in the classification cocoa agroforestry. The study was carried out in Côte d’Ivoire, close to the Taï National Park. The analysis followed three steps (i) image classification based on texture parameters and vegetation indices from Sentinel-1 and -2 data respectively, to train a random forest algorithm. A classified map with the associated probability maps was generated. (ii) Shannon entropy was calculated from the probability maps, to get the error maps at different thresholds (0.2, 0.3, 0.4 and 0.5). Then, (iii) the generated error maps were analysed using a Geographically Weighted Regression model to check for spatial autocorrelation. From the results, a producer accuracy (0.88) and a user’s accuracy (0.91) were obtained. A small threshold value overestimates the classification error, while a larger threshold will underestimate it. The optimal value was found to be between 0.3 and 0.4. There was no evidence of spatial autocorrelation except for a smaller threshold (0.2). The approach differentiated cocoa from other landcover and detected encroachment in forest. Even though some information was lost in the process, the method is effective for mapping cocoa plantations in Côte d’Ivoire. KW - cocoa mapping KW - geographically weighted regression KW - Sentinel-1 KW - Sentinel-2 KW - Shannon entropy KW - spatial error assessment Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324139 SN - 0167-4366 VL - 97 IS - 1 ER - TY - JOUR A1 - Frimmel, Hartwig E. A1 - Chakravarti, Rajarshi A1 - Basei, Miguel A. S. T1 - Detrital zircon ages from Archaean conglomerates in the Singhbhum Craton, eastern India: implications on economic Au-U potential JF - Mineralium Deposita N2 - New U–Pb age and Hf isotope data obtained on detrital zircon grains from Au- and U-bearing Archaean quartz-pebble conglomerates in the Singhbhum Craton, eastern India, specifically the Upper Iron Ore Group in the Badampahar Greenstone Belt and the Phuljhari Formation below the Dhanjori Group provide insights into the zircon provenance and maximum age of sediment deposition. The most concordant, least disturbed \(^{207}\)Pb/\(^{206}\)Pb ages cover the entire range of known magmatic and higher grade metamorphic events in the craton from 3.48 to 3.06 Ga and show a broad maximum between 3.38 and 3.18 Ga. This overlap is also mimicked by Lu–Hf isotope analyses, which returned a wide range in \(_{εHf}\)(t) values from + 6 to − 5, in agreement with the range known from zircon grains in igneous and metamorphic rocks in the Singhbhum Craton. A smaller but distinct age peak centred at 3.06 Ga corresponds to the age of the last major magmatic intrusive event, the emplacement of the Mayurbhanj Granite and associated gabbro, picrite and anorthosite. Thus, these intrusive rocks must form a basement rather than being intrusive into the studied conglomerates as previously interpreted. The corresponding detrital zircon grains all have a subchondritic Hf isotopic composition. The youngest reliable zircon ages of 3.03 Ga in the case of the basal Upper Iron Ore Group in the east of the craton and 3.00 Ga for the Phuljhari Formation set an upper limit on the age of conglomerate sedimentation. Previously published detrital zircon age data from similarly Au-bearing conglomerates in the Mahagiri Quartzite in the Upper Iron Ore Group in the south of the craton gave a somewhat younger maximum age of sedimentation of 2.91 Ga. There, the lower limit on sedimentation is given by an intrusive relationship with a c. 2.8 Ga granite. The time window thus defined for conglomerate deposition on the Singhbhum Craton is almost identical to the age span established for the, in places, Au- and U-rich conglomerates in the Kaapvaal Craton of South Africa: the 2.98–2.78 Ga Dominion Group and Witwatersrand Supergroup in South Africa. Since the recognition of first major concentration of gold on Earth’s surface by microbial activity having taken place at around 2.9 Ga, independent of the nature of the hinterland, the above similarity in age substantially increases the potential for discovering Witwatersrand-type gold and/or uranium deposits on the Singhbhum Craton. Further age constraints are needed there, however, to distinguish between supposedly less fertile (with respect to Au) > 2.9 Ga and more fertile < 2.9 Ga successions. KW - quartz-pebble conglomerate KW - gold KW - Mesoarchaean KW - Singhbhum Craton KW - zircon geochronology Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324084 SN - 0026-4598 VL - 57 IS - 8 ER - TY - JOUR A1 - Ibebuchi, Chibuike Chiedozie T1 - Circulation patterns linked to the positive sub-tropical Indian Ocean dipole JF - Advances in Atmospheric Sciences N2 - The positive phase of the subtropical Indian Ocean dipole (SIOD) is one of the climatic modes in the subtropical southern Indian Ocean that influences the austral summer inter-annual rainfall variability in parts of southern Africa. This paper examines austral summer rain-bearing circulation types (CTs) in Africa south of the equator that are related to the positive SIOD and the dynamics through which specific rainfall regions in southern Africa can be influenced by this relationship. Four austral summer rain-bearing CTs were obtained. Among the four CTs, the CT that featured (i) enhanced cyclonic activity in the southwest Indian Ocean; (ii) positive widespread rainfall anomaly in the southwest Indian Ocean; and (iii) low-level convergence of moisture fluxes from the tropical South Atlantic Ocean, tropical Indian Ocean, and the southwest Indian Ocean, over the south-central landmass of Africa, was found to be related to the positive SIOD climatic mode. The relationship also implies that positive SIOD can be expected to increase the amplitude and frequency of occurrence of the aforementioned CT. The linkage between the CT related to the positive SIOD and austral summer homogeneous regions of rainfall anomalies in Africa south of the equator showed that it is the principal CT that is related to the inter-annual rainfall variability of the south-central regions of Africa, where the SIOD is already known to significantly influence its rainfall variability. Hence, through the large-scale patterns of atmospheric circulation associated with the CT, the SIOD can influence the spatial distribution and intensity of rainfall over the preferred landmass through enhanced moisture convergence. KW - subtropical Indian Ocean dipole KW - circulation types KW - rainfall KW - South Indian Ocean KW - moisture convergence Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324119 SN - 0256-1530 VL - 40 IS - 1 ER - TY - JOUR A1 - Fäth, Julian A1 - Kunz, Julius A1 - Kneisel, Christof T1 - Monitoring spatiotemporal soil moisture changes in the subsurface of forest sites using electrical resistivity tomography (ERT) JF - Journal of Forestry Research N2 - The effects of drought on tree mortality at forest stands are not completely understood. For assessing their water supply, knowledge of the small-scale distribution of soil moisture as well as its temporal changes is a key issue in an era of climate change. However, traditional methods like taking soil samples or installing data loggers solely collect parameters of a single point or of a small soil volume. Electrical resistivity tomography (ERT) is a suitable method for monitoring soil moisture changes and has rarely been used in forests. This method was applied at two forest sites in Bavaria, Germany to obtain high-resolution data of temporal soil moisture variations. Geoelectrical measurements (2D and 3D) were conducted at both sites over several years (2015–2018/2020) and compared with soil moisture data (matric potential or volumetric water content) for the monitoring plots. The greatest variations in resistivity values that highly correlate with soil moisture data were found in the main rooting zone. Using the ERT data, temporal trends could be tracked in several dimensions, such as the interannual increase in the depth of influence from drought events and their duration, as well as rising resistivity values going along with decreasing soil moisture. The results reveal that resistivity changes are a good proxy for seasonal and interannual soil moisture variations. Therefore, 2D- and 3D-ERT are recommended as comparatively non-laborious methods for small-spatial scale monitoring of soil moisture changes in the main rooting zone and the underlying subsurface of forested sites. Higher spatial and temporal resolution allows a better understanding of the water supply for trees, especially in times of drought. KW - geoelectrical monitoring KW - forest ecology KW - hydrology KW - soil water content Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324073 SN - 1007-662X VL - 33 IS - 5 ER - TY - JOUR A1 - Ibebuchi, Chibuike Chiedozie T1 - Patterns of atmospheric circulation in Western Europe linked to heavy rainfall in Germany: preliminary analysis into the 2021 heavy rainfall episode JF - Theoretical and Applied Climatology N2 - The July 2021 heavy rainfall episode in parts of Western Europe caused devastating floods, specifically in Germany. This study examines circulation types (CTs) linked to extreme precipitation in Germany. It was investigated if the classified CTs can highlight the anomaly in synoptic patterns that contributed to the unusual July 2021 heavy rainfall in Germany. The North Atlantic Oscillation was found to be the major climatic mode related to the seasonal and inter-annual variations of most of the classified CTs. On average, wet (dry) conditions in large parts of Germany can be linked to westerly (northerly) moisture fluxes. During spring and summer seasons, the mid-latitude cyclone when located over the North Sea disrupts onshore moisture transport from the North Atlantic Ocean by westerlies driven by the North Atlantic subtropical anticyclone. The CT found to have the highest probability of being associated with above-average rainfall in large part of Germany features (i) enhancement and northward track of the cyclonic system over the Mediterranean; (ii) northward track of the North Atlantic anticyclone, further displacing poleward, the mid-latitude cyclone over the North Sea, enabling band of westerly moisture fluxes to penetrate Germany; (iii) cyclonic system over the Baltic Sea coupled with northeast fluxes of moisture to Germany; (iv) and unstable atmospheric conditions over Germany. In 2021, a spike was detected in the amplitude and frequency of occurrence of the aforementioned wet CT suggesting that in addition to the nearly stationary cut-off low over central Europe, during the July flood episode, anomalies in the CT contributed to the heavy rainfall event. KW - circulation type (CT) KW - atmospheric circulation KW - Western Europe KW - Germany KW - flood KW - heavy rainfall Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324100 SN - 0177-798X VL - 148 IS - 1-2 ER - TY - JOUR A1 - Philipp, Marius A1 - Dietz, Andreas A1 - Ullmann, Tobias A1 - Kuenzer, Claudia T1 - A circum-Arctic monitoring framework for quantifying annual erosion rates of permafrost coasts JF - Remote Sensing N2 - This study demonstrates a circum-Arctic monitoring framework for quantifying annual change of permafrost-affected coasts at a spatial resolution of 10 m. Frequent cloud coverage and challenging lighting conditions, including polar night, limit the usability of optical data in Arctic regions. For this reason, Synthetic Aperture RADAR (SAR) data in the form of annual median and standard deviation (sd) Sentinel-1 (S1) backscatter images covering the months June–September for the years 2017–2021 were computed. Annual composites for the year 2020 were hereby utilized as input for the generation of a high-quality coastline product via a Deep Learning (DL) workflow, covering 161,600 km of the Arctic coastline. The previously computed annual S1 composites for the years 2017 and 2021 were employed as input data for the Change Vector Analysis (CVA)-based coastal change investigation. The generated DL coastline product served hereby as a reference. Maximum erosion rates of up to 67 m per year could be observed based on 400 m coastline segments. Overall highest average annual erosion can be reported for the United States (Alaska) with 0.75 m per year, followed by Russia with 0.62 m per year. Out of all seas covered in this study, the Beaufort Sea featured the overall strongest average annual coastal erosion of 1.12 m. Several quality layers are provided for both the DL coastline product and the CVA-based coastal change analysis to assess the applicability and accuracy of the output products. The predicted coastal change rates show good agreement with findings published in previous literature. The proposed methods and data may act as a valuable tool for future analysis of permafrost loss and carbon emissions in Arctic coastal environments. KW - permafrost KW - coastal erosion KW - circum-Arctic KW - deep learning KW - change vector analysis KW - Google Earth Engine KW - synthetic aperture RADAR Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304447 SN - 2072-4292 VL - 15 IS - 3 ER - TY - JOUR A1 - Kacic, Patrick A1 - Thonfeld, Frank A1 - Gessner, Ursula A1 - Kuenzer, Claudia T1 - Forest structure characterization in Germany: novel products and analysis based on GEDI, Sentinel-1 and Sentinel-2 data JF - Remote Sensing N2 - Monitoring forest conditions is an essential task in the context of global climate change to preserve biodiversity, protect carbon sinks and foster future forest resilience. Severe impacts of heatwaves and droughts triggering cascading effects such as insect infestation are challenging the semi-natural forests in Germany. As a consequence of repeated drought years since 2018, large-scale canopy cover loss has occurred calling for an improved disturbance monitoring and assessment of forest structure conditions. The present study demonstrates the potential of complementary remote sensing sensors to generate wall-to-wall products of forest structure for Germany. The combination of high spatial and temporal resolution imagery from Sentinel-1 (Synthetic Aperture Radar, SAR) and Sentinel-2 (multispectral) with novel samples on forest structure from the Global Ecosystem Dynamics Investigation (GEDI, LiDAR, Light detection and ranging) enables the analysis of forest structure dynamics. Modeling the three-dimensional structure of forests from GEDI samples in machine learning models reveals the recent changes in German forests due to disturbances (e.g., canopy cover degradation, salvage logging). This first consistent data set on forest structure for Germany from 2017 to 2022 provides information of forest canopy height, forest canopy cover and forest biomass and allows estimating recent forest conditions at 10 m spatial resolution. The wall-to-wall maps of the forest structure support a better understanding of post-disturbance forest structure and forest resilience. KW - forest KW - forest structure Germany KW - canopy height KW - Global Ecosystem Dynamics Investigation KW - GEDI KW - Sentinel-1 KW - Sentinel-2 KW - random forest regression Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313727 SN - 2072-4292 VL - 15 IS - 8 ER -