@misc{HerrmannKeulerWoltersetal., author = {Herrmann, Frank and Keuler, Klaus and Wolters, Tim and Bergmann, Sabine and Eisele, Michael and Wendland, Frank}, title = {Mit der Modellkette RCP-GCM-RCM-mGROWA projizierte Grundwasserneubildung als Datenbasis f{\"u}r zuk{\"u}nftiges Grundwassermanagement in Nordrhein-Westfalen}, series = {Grundwasser}, volume = {26}, journal = {Grundwasser}, number = {1}, issn = {1430-483X}, doi = {10.1007/s00767-020-00471-x}, pages = {17 -- 31}, abstract = {Mit einem Multi-Modell-Ensemble wurde analysiert, wie sich der Klimawandel auf den Grundwasserhaushalt in Nordrhein-Westfalen (NRW) auswirkt. Hierzu wurden Projektionen der zuk{\"u}nftigen Grundwasserneubildung f{\"u}r insgesamt 36 Mitglieder der Modellkette RCP-GCM-RCM-mGROWA, bestehend aus 3 RCP-Szenarien zuk{\"u}nftiger globaler Erw{\"a}rmung, 6 globalen und 5 dynamischen regionalen Klimamodellen sowie dem Wasserhaushaltsmodell mGROWA, vorgenommen. Mit dem Ensemble wurden f{\"u}r die hydrogeologischen Großr{\"a}ume NRWs nur teilweise signifikante {\"A}nderungen der j{\"a}hrlichen Grundwasserneubildung in den Perioden 2011-2040, 2041-2070 und 2071-2100 projiziert. Ein Robustheitstest mit zwei Kriterien ({\"U}bereinstimmung und Signifikanz der {\"A}nderungssignale) liefert keine belastbare Begr{\"u}ndung daf{\"u}r, dass sich die Grundwasserneubildung bis 2100 systematisch und signifikant {\"a}ndern wird. Aus statistischer Perspektive wird deshalb die Schlussfolgerung gezogen, dass in NRW langfristig eine Grundwasserneubildung erwartet werden kann, die sich nicht grundlegend vom Niveau der Periode 1971-2000 unterscheidet. Hydro-meteorologisch befindet sich NRW in einer {\"U}bergangszone, in der eine Zunahme der Winterniederschl{\"a}ge die Wirkung der Erw{\"a}rmung auf die Grundwasserneubildung wahrscheinlich kompensiert.}, language = {de} } @misc{TrachteRaffelsbauer, author = {Trachte, Katja and Raffelsbauer, Volker}, title = {Trees with anisohydric behavior as main drivers of nocturnal evapotranspiration in a tropical mountain rainforest}, series = {PLoS ONE}, volume = {18 (3)}, journal = {PLoS ONE}, doi = {10.1371/journal.pone.0282397}, pages = {1 -- 21}, language = {en} } @misc{BhawarKumarLawandetal., author = {Bhawar, Rohini L. and Kumar, Vinay and Lawand, Divyaja and Kedia, Sumita and Naik, Mrunal and Modale, Shripriya and Reddy, P. R. C. and Islam, Sahidul and Khare, Manoj}, title = {Aerosol emission patterns from the February 2019 Karnataka fire}, series = {Fire}, volume = {7}, journal = {Fire}, number = {12}, editor = {Williamson, Grant}, publisher = {MDPI}, address = {Basel}, issn = {2571-6255}, doi = {10.3390/fire7120424}, pages = {1 -- 15}, abstract = {Forests are vital for life on Earth but are threatened by forest fires, which have significant impacts on climate change both locally and globally. This study examines a forest fire that lasted from 15 to 26 February 2019 in Karnataka, India, using the Weather Research and Forecasting model with Chemistry (WRF-Chem) model to analyze the effects and atmospheric spread of fire-emitted aerosols. Model simulations are analyzed to understand the horizontal and vertical transport and radiative effects of the fire. The results show high aerosol levels and smoke particles reaching up to 3.5 km altitude and above. The fire raised near-surface air temperatures by ~1-1.5 °C. The net atmospheric forcing due to the fire over the affected area ranged from approximately 10 to 14 W/m 2 , resulting in heating rates between about 0.002 and 0.005 K/day in the impacted region.}, language = {en} } @misc{GrigusovaLimbergerMurkuteetal., author = {Grigusova, Paulina and Limberger, Oliver and Murkute, Charuta and Pucha-Cofrep, Franz and Gonzalez-Jaramillo, Victor Hugo and Fries, Andreas and Windhorst, David and Breuer, Lutz and Dantas de Paula, Mateus and Hickler, Thomas and Trachte, Katja and Bendix, J{\"o}rg}, title = {Radiation partitioning in a cloud-rich tropical mountain rain forest of the S-Ecuadorian Andes for use in plot-based land surface modelling}, series = {Dynamics of atmospheres and oceans : planetary fluid, climatic and biogeochemical systems}, volume = {110}, journal = {Dynamics of atmospheres and oceans : planetary fluid, climatic and biogeochemical systems}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0377-0265}, doi = {10.1016/j.dynatmoce.2025.101553}, pages = {1 -- 16}, abstract = {Understanding the partitioning of downward shortwave radiation into direct and diffuse components is essential for modeling ecosystem energy fluxes. Accurate partitioning functions are critical for land surface models (LSMs) coupled with climate models, yet these functions often depend on regional cloud and aerosol conditions. While data for developing semi-empirical partitioning functions are abundant in mid-latitudes, their performance in tropical regions, particularly in the high Andes, remains poorly understood due to scarce ground-based measurements. This study analyzed a unique dataset of shortwave radiation components from a tropical mountain rainforest (MRF) in southern Ecuador, developing and testing a locally adapted partitioning function using Random Forest Regression. The model achieved high accuracy in predicting the percentage of diffuse radiation (\%Dif; R²=0.95, RMSE = 5.33, MAE = 3.74) and absolute diffuse radiation (R²=0.99, RMSE = 5.30, MAE = 14). When applied to simulate upward shortwave radiation, the model outperformed commonly used partitioning functions achieving the lowest RMSE (8.62) and MAE (5.82) while matching the highest R² (0.97). These results underscore the importance of regionally adapted radiation partitioning functions for improving LSM performance, particularly in complex tropical environments. The adapted LSM will be further utilized for studies on heat fluxes and carbon sequestration.}, language = {en} } @misc{BendixLimburgerBreueretal., author = {Bendix, J{\"o}rg and Limburger, Oliver and Breuer, Lutz and Dantas de Paula, Mateus and Fries, Andreas and Gonzalez-Jaramillo, Victor Hugo and Grigusova, Paulina and Hickler, Thomas and Murkute, Charuta and Pucha-Cofrep, Franz and Trachte, Katja and Windhorst, David}, title = {Simulation of latent heat flux over a high altitude pasture in the tropical Andes with a coupled land surface framework}, series = {The science of the total environment}, volume = {981}, journal = {The science of the total environment}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-1026}, doi = {10.1016/j.scitotenv.2025.179510}, pages = {1 -- 21}, abstract = {Latent heat flux is a central element of land-atmosphere interactions under climate change. Knowledge is particularly poor in the biodiversity hotspot of the Andes, where heat flux measurements using eddy covariance stations are scarce and land surface models (LSMs) often oversimplify the complexity of the ecosystems. The main objective of this study is to perform latent heat flux simulations for the tropical South Eastern (SE) Ecuadorian Andes using a coupled LSM framework, and to test the performance with heat flux and soil moisture data collected from a tropical high-altitude pasture. Prior to testing, we applied multi-criteria model calibration of sensitive model parameters, focusing on improving simulated soil water conditions and radiation fluxes as a prerequisite for proper heat flux simulations. The most sensitive parameters to improve soil moisture and radiation flux simulations were soil porosity, saturated hydraulic conductivity, leaf area index, soil colour and NIR (Near Infrared) leaf optical properties. The best calibrated model run showed a very good performance for half-hourly latent heat flux simulations with an R² of 0.8 and an RMSE of 34.0 W m⁻², outperforming simulations with uncalibrated and uncoupled LSM simulations in comparable areas. The slight overall overestimation in the simulated latent heat flux can be related to (i) simulation uncertainties in the canopy heat budget, (ii) an imbalance in the observed flux data and (iii) slight overestimations in the simulated soil moisture. Although our study focuses on latent heat fluxes and their relation to simulated radiation fluxes and soil moisture, model outputs of sensible heat fluxes were also discussed. The systematic overestimation of sensible heat flux in the model seems to be mainly a result of overestimated canopy temperatures. The improved simulation for latent heat flux has a high translational potential to support land use strategies in the tropical Andes under climate change.}, language = {en} } @misc{LimbergerHomeierGonzalezJaramilloetal., author = {Limberger, Oliver and Homeier, J{\"u}rgen and Gonzalez-Jaramillo, Victor and Fries, Andreas and Murkute, Charuta and Trachte, Katja and Bendix, J{\"o}rg}, title = {Foliar trait retrieval models based on hyperspectral satellite imagery perform well in a biodiversity hotspot of the SE Ecuadorian Andes}, series = {International journal of remote sensing}, journal = {International journal of remote sensing}, publisher = {Taylor \& Francis}, address = {London}, issn = {1366-5901}, doi = {10.1080/01431161.2025.2511211}, pages = {1 -- 19}, abstract = {The determination of the spatial distribution of canopy traits is crucial for understanding the spatio-temporal dynamics of ecosystem functions, such as carbon sequestration, water and energy fluxes in tropical montane forests. Especially in remote areas such as the Andes of south-east Ecuador, remote sensing using satellites has been proven to provide valuable information on canopy traits. However, the performance of the multispectral models to date is limited. Here, we analyse the potential of DESIS (DLR Earth Sensing Imaging Spectrometer) hyperspectral surface reflectance data for the prediction of specific leaf area (SLA), foliar toughness, nitrogen (N) and phosphorus (P) content by calibrating a PLSR model for each foliar trait. Model validation showed a high explanation of variance (R2 : 0.78-0.92) and a low model error (mean-normalized RMSE: 8-13\%) for all traits, showing an improved performance compared to models based on multispectral imagery and ancillary data within the same forest type. Hyperspectral models predicting foliar traits from individual tree crowns showed a lower performance for most traits, probably related to the difference in spatial resolution compared to this study. Given the high species richness of the Andean biodiversity hotspot and the complex topography, the high quality of the DESIS models is remarkable, considering that the multispectral models from the region require topographic predictors in addition to reflectances to achieve a good performance. The spatial trait maps generated by our models based on the reflectances only show clear relationships with terrain elevation. Thus, the hyperspectral trait maps from satellite orbit are capable of supporting large-scale ecological analyses between features, diversity and ecosystem functions.}, language = {en} } @misc{SaraviaTrachte, author = {Saravia, Christian and Trachte, Katja}, title = {Spatiotemporal analysis of NH₃ emission sources and their relation to land use types in the Eastern German lowlands}, series = {Atmosphere}, volume = {16}, journal = {Atmosphere}, publisher = {MDPI}, address = {Basel}, issn = {2073-4433}, doi = {10.3390/atmos16030346}, pages = {1 -- 21}, abstract = {Ammonia (NH₃) emissions, which are key precursors of fine particulate matter, pose significant environmental challenges. This study investigated the spatiotemporal variations in NH₃ emissions across the eastern German lowlands from 2013 to 2022 using IASI-B satellite data. Five major Land Cover Classes (LCC) -tree, grassland, cropland, built-up areas, and water bodies- were analyzed. The results showed distinct diurnal variations, with nighttime NH₃ concentrations exceeding 2.0 × 10¹⁶ molecules cm⁻² in the peak months. Seasonal patterns indicated significant emissions in March (1.2 × 10¹⁶ molecules cm⁻²), April (1.1 × 10¹⁶ molecules cm⁻2), and August (9.6 × 10¹⁵ molecules cm⁻²), while the lowest concentrations occurred in September (0.6 × 10¹⁵ molecules cmv²). Persistent hotspots were identified in the northwestern region, where emissions peaked in spring (1.8 × 10¹⁶ molecules cm⁻²) and summer (1.3 × 10¹⁶ molecules cm⁻²), primarily due to agricultural activities. Over the study period, the annual NH₃ concentration peaked in 2015, 2018, and 2022. Using k-means clustering, three distinct emission zones were identified, with Cluster 3 showing the highest NH₃ emission values, particularly in urban centers, and agricultural zones were identified, covering less than 20\% of the study area, where cropland predominates (8\%). Meteorological factors significantly influenced NH₃ levels, with negative correlations obtained for precipitation, wind speed, and evaporation, while solar radiation, boundary layer height, and instantaneous moisture fluxes showed positive correlations. A case study from March 2022, employing the HYSPLIT trajectory model, confirmed that agricultural practices are the dominant NH₃ source, with emissions reaching 3.2 × 10¹⁶ molecules cm⁻² in hotspot regions.}, language = {en} } @misc{AhmadpourBayzidiTrachte, author = {Ahmadpour, Somayeh and Bayzidi, Yasin and Trachte, Katja}, title = {Spatio-temporal patterns of evapotranspiration in the temperate Eastern German lowlands and its response to climate and land use change}, series = {Theoretical and applied climatology}, volume = {156}, journal = {Theoretical and applied climatology}, publisher = {Springer}, issn = {1434-4483}, doi = {10.1007/s00704-025-05529-5}, pages = {1 -- 19}, abstract = {Evapotranspiration (ET) is a key factor in the water and energy cycle, playing a critical role, especially in agricultural regions. The eastern German lowlands, with their continental climate, are one of the driest regions in Germany, yet agriculture is the dominant land use. This study investigates the spatio-temporal variability of ET and its response to climate and land use/land cover change (LUCC) using MODIS remote sensing products and in-situ measurements over the period 2000-2020. The results show a slight increase in the mean annual ET, with local increases of up to 7.2\% in the southern and southeastern parts of Brandenburg. LUCC revealed a 22.2\% decrease in grassland to cropland conversion, leading to a decline in ET of 21\%, while conversion from grassland to cropland increased by 14.8\%, resulting in a 10\% increase in ET. The strongest relationship with ET was found for vapor pressure deficit (VPD), temperature (Temp), and relative humidity (RH), which contributed 25.2\%, 30.9\%, and 23.2\%, respectively, to its total variability. In addition to atmospheric factors soil moisture (SM) also contributed 17.7\% to ET, but only in grassland. LUCC played a minor role as 22\% of the study area was under conversion. Consequently, climate change, represented by the temporal change of the climatic factors, was identified as the dominant driver of ET in the study area, accounting for 97\% of its variability. Accordingly, these findings underscore the importance of Temp, RH, and SM in agricultural and water resource management.}, language = {en} } @misc{LauxFeldmannMarraetal., author = {Laux, Patrick and Feldmann, David and Marra, Francesco and Feldmann, Hendrik and Kunstmann, Harald and Trachte, Katja and Peleg, Nadav}, title = {Future precipitation extremes and urban flood risk assessment using a non-stationary and convection-permitting climate-hydrodynamic modeling framework}, series = {Journal of hydrology}, volume = {661, Part B}, journal = {Journal of hydrology}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-2707}, doi = {10.1016/j.jhydrol.2025.133607}, pages = {1 -- 14}, abstract = {Urban planners and engineers rely on historical climate data to plan and design flood protection infrastructure that should withstand extreme flooding events with 1\% annual exceedance probability (the 100-year flood). Here, we examine how hourly precipitation extremes are expected to change as temperatures rise and how this will affect urban flooding. The changes to short-duration rainfall extremes, often insufficiently considered in practice, are addressed utilizing a new temperature conditional extreme precipitation scaling approach and a novel regional climate convection-permitting model ensemble for +2 °C and +3 °C global warming scenarios. Based on hydrodynamic modeling, we estimate how future precipitation extremes translate into flood risks in two pre-alpine communes in Germany. Ignoring the impacts of climate change may lead to severe underestimations of flood risks. The +3 °C global warming scenario translates into an increase of 60\% of affected buildings by the highest flood risk category (water level of 1 m and above). The increase in flow intensities will be greater in the commune characterized by steeper terrain. The results suggest that recently planned or implemented infrastructure projects may not be adequately equipped to cope with the anticipated effects of climate change in the coming decades.}, language = {en} } @misc{GerwinRaabHinzetal., author = {Gerwin, Werner and Raab, Thomas and Hinz, Christoph and Letmathe, Peter and Leuchner, Michael and Roß-Nickoll, Martina and R{\"u}de, Thomas and Trachte, Katja and W{\"a}tzold, Frank and Lehmkuhl, Frank}, title = {Perspectives of lignite post‑mining landscapes under changing environmental conditions: what can we learn from a comparison between the Rhenish and Lusatian region in Germany?}, series = {Environmental Sciences Europe}, volume = {35}, journal = {Environmental Sciences Europe}, issn = {2190-4715}, doi = {10.1186/s12302-023-00738-z}, abstract = {Background The decision of the German federal government to cease lignite mining until 2038 or—if possible— already earlier until 2030, will cause manifold transition processes in the remaining lignite mining districts of Germany. The two largest districts are located in geographically opposite regions: The Rhineland in the western part and Lusatia in the east of Germany. As particularly these two mining districts will experience severe changes in their socioeconomic as well environmental conditions, the federal government has adopted comprehensive economic support measures. However, the environmental changes will also cause altered ecosystem functions and services to be provided by the future post-mining landscapes. Results In this paper, the two main lignite-producing regions of Germany are compared with regard to their natural and cultural settings. The economic situation and its history are reflected and differences are outlined. Part of the disparities in the cultural development can be explained by very different natural conditions, especially edaphic factors and climatic situation. Because of dissimilar geological settings, different mining technologies were developed and are in use in the two regions with distinct effects on the resulting post-mining landscapes. Conclusion The long-standing and manifold lignite mining activities have radically restructured the landscapes in Lusatia and the Rhineland. With the ongoing decline of the mining industry and its complete cessation, presumably within the next decade, both regions will alter their faces significantly. These changes offer both challenges but also opportunities with respect to the post-mining landscapes and their ecosystem services they are going to provide. The prerequisites for a positive socioeconomic development and for sustainable land-use concepts that also consider ecological aspects are different for both regions. However, or especially because of these differences, the knowledge exchange and experience transfer between both mining regions are pivotal for the success of this extensive transformation process.}, language = {en} } @misc{LehmkuhlGerwinRaabetal., author = {Lehmkuhl, Frank and Gerwin, Werner and Raab, Thomas and Birkhofer, Klaus and Hinz, Christoph and Letmathe, Peter and Leuchner, Michael and Roß-Nickoll, Martina and R{\"u}de, Thomas R. and Trachte, Katja and W{\"a}tzold, Frank}, title = {Perspectives for the lignite post-mining landscapes of the lignite mining landscapes under changing environmental conditions - what can we learn from a comparison between the Rhenish and the Lusatian regions in Germany? : EGU General Assembly 2024, Vienna, Austria \& Online | 14-19 April 2024}, publisher = {Copernicus GmbH}, doi = {10.5194/egusphere-egu24-2791}, abstract = {The German government's decision to phase out lignite mining by 2038 or earlier, as recently 2030 has been agreed for the Rhineland, will trigger a number of transition processes in Germany's remaining lignite mining areas. The two largest lignite mining areas are located in geographically different regions: Rhineland in the west and Lusatia in the east. As the socio-economic and environmental conditions in these two mining areas are set to change dramatically, the German government has adopted extensive economic support measures. However, the environmental changes will also lead to changes in the ecosystem functions and services provided by the future post-mining landscapes. Gerwin et al. (2023) compare the two main lignite producing regions of Germany in terms of their natural and cultural environments. The economic situation and its history are reflected and differences are outlined. Part of the differences in cultural development can be explained by the natural conditions, especially the edaphic factors and the climatic situation. Because of the specific geological settings, tailored mining technologies were developed and used in the two regions, with different effects on the resulting post-mining landscapes. We conclude that the landscapes of Lusatia and the Rhineland have been radically restructured by the long and varied history of lignite mining. Both regions will change significantly as the mining industry continues to decline and is expected to cease altogether within the next decade. These changes in the post-mining landscapes and the ecosystem services will provide both challenges and opportunities. The preconditions for positive socio-economic development and for sustainable land use concepts that also consider ecological aspects are different for the two regions. The exchange of knowledge and experience between the two mining regions is crucial to the success of this major transformation process, despite, or perhaps because of, these differences. Gerwin, W., Raab, T., Birkhofer, K., Hinz, C., Letmathe, P., Leuchner, M., Ro\&\#223;-Nickoll, M., R\&\#252;de, T., Trachte, K., W\&\#228;tzold, F., Lehmkuhl, F. (2023): Perspectives of lignite post-mining landscapes under changing environmental conditions: what can we learn from a comparison between the Rhenish and Lusatian region in Germany? Environmental Sciences Europe 35:36. https://doi.org/10.1186/s12302-023-00738-z}, language = {en} } @misc{MolinaCaretoGutierrezetal., author = {Molina, M. O. and Careto, J. M. and Guti{\´e}rrez, C. and S{\´a}nchez, E. and Goergen, K. and Sobolowski, S. and Coppola, E. and Pichelli, E. and Ban, N. and Belus̆ić, D. and Short, C. and Caillaud, C. and Dobler, A. and Hodnebrog, {\O}. and Kartsios, S. and Lenderink, G. and de Vries, H. and G{\"o}kt{\"u}rk, O. and Milovac, J. and Feldmann, H. and Truhetz, H. and Demory, M. E. and Warrach-Sagi, K. and Keuler, K. and Adinolfi, M. and Raffa, M. and T{\"o}lle, M. and Sieck, K. and Bastin, S. and Soares, P. M. M.}, title = {The added value of simulated near-surface wind speed over the Alps from a km-scale multimodel ensemble}, series = {Climate dynamics}, volume = {62}, journal = {Climate dynamics}, number = {6}, publisher = {Springer}, address = {Berlin ; Heidelberg}, issn = {0930-7575}, doi = {10.1007/s00382-024-07257-4}, pages = {4697 -- 4715}, abstract = {The advancement of computational resources has allowed researchers to run convection-permitting regional climate model (CPRCM) simulations. A pioneering effort promoting a multimodel ensemble of such simulations is the CORDEX Flagship Pilot Studies (FPS) on "Convective Phenomena over Europe and the Mediterranean" over an extended Alps region. In this study, the Distribution Added Value metric is used to determine the improvement of the representation of all available FPS hindcast simulations for the daily mean near-surface wind speed. The analysis is performed on normalized empirical probability distributions and considers station observation data as the reference. The use of a normalized metric allows for spatial comparison among the different regions (coast and inland), altitudes and seasons. This approach permits a direct assessment of the added value between the CPRCM simulations against their global driving reanalysis (ERA-Interim) and respective coarser resolution regional model counterparts. In general, the results show that CPRCMs add value to their global driving reanalysis or forcing regional model, due to better-resolved topography or through better representation of ocean-land contrasts. However, the nature and magnitude of the improvement in the wind speed representation vary depending on the model, the season, the altitude, or the region. Among seasons, the improvement is usually larger in summer than winter. CPRCMs generally display gains at low and medium-range altitudes. In addition, despite some shortcomings in comparison to ERA-Interim, which can be attributed to the assimilation of wind observations on the coast, the CPRCMs outperform the coarser regional climate models, both along the coast and inland.}, language = {en} }