Search Results - "Ullmann, Tobias"

Surface Roughness Estimation in the Orog Nuur Basin (Southern Mongolia) Using Sentinel-1 SAR Time Series and Ground-Based Photogrammetry by Ullmann, Tobias, Stauch, Georg

“…This study demonstrates an application-oriented approach to estimate area-wide surface roughness from Sentinel-1 time series in the semi-arid environment of…”
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Mapping and Monitoring Small-Scale Mining Activities in Ghana using Sentinel-1 Time Series (2015–2019) by Forkuor, Gerald, Ullmann, Tobias, Griesbeck, Mario

“…Illegal small-scale mining (galamsey) in South-Western Ghana has grown tremendously in the last decade and caused significant environmental degradation…”
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State of the Vietnamese Coast—Assessing Three Decades (1986 to 2021) of Coastline Dynamics Using the Landsat Archive by Lappe, Ronja, Ullmann, Tobias, Bachofer, Felix

“…Vietnam’s 3260 km coastline is densely populated, experiences rapid urban and economic growth, and faces at the same time a high risk of coastal hazards…”
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Automated Extraction of Annual Erosion Rates for Arctic Permafrost Coasts Using Sentinel-1, Deep Learning, and Change Vector Analysis by Philipp, Marius, Dietz, Andreas, Ullmann, Tobias, Kuenzer, Claudia

“…Arctic permafrost coasts become increasingly vulnerable due to environmental drivers such as the reduced sea-ice extent and duration as well as the thawing of…”
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Integration of Optical and Synthetic Aperture Radar Imagery for Improving Crop Mapping in Northwestern Benin, West Africa by kuor, Gerald, Conrad, Christopher, Thiel, Michael, Ullmann, Tobias, Zoungrana, Evence

“…Crop mapping in West Africa is challenging, due to the unavailability of adequate satellite images (as a result of excessive cloud cover), small agricultural…”
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A Circum-Arctic Monitoring Framework for Quantifying Annual Erosion Rates of Permafrost Coasts by Philipp, Marius, Dietz, Andreas, Ullmann, Tobias, Kuenzer, Claudia

“…This study demonstrates a circum-Arctic monitoring framework for quantifying annual change of permafrost-affected coasts at a spatial resolution of 10 m…”
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Detection of Grassland Mowing Events for Germany by Combining Sentinel-1 and Sentinel-2 Time Series by Reinermann, Sophie, Gessner, Ursula, Asam, Sarah, Ullmann, Tobias, Schucknecht, Anne, Kuenzer, Claudia

“…Grasslands cover one-third of the agricultural area in Germany and play an important economic role by providing fodder for livestock. In addition, they fulfill…”
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Estimation of Aboveground Biomass in Agroforestry Systems over Three Climatic Regions in West Africa Using Sentinel-1, Sentinel-2, ALOS, and GEDI Data by Kanmegne Tamga, Dan, Latifi, Hooman, Ullmann, Tobias, Baumhauer, Roland, Bayala, Jules, Thiel, Michael

“…Agroforestry systems (AFS) offer viable solutions for climate change because of the aboveground biomass (AGB) that is maintained by the tree component…”
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The Impact of Phenological Developments on Interferometric and Polarimetric Crop Signatures Derived from Sentinel-1: Examples from the DEMMIN Study Site (Germany) by Löw, Johannes, Ullmann, Tobias, Conrad, Christopher

“…This study explores the potential of Sentinel-1 Synthetic Aperture Radar (SAR) to identify phenological phases of wheat, sugar beet, and canola. Breakpoint and…”
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Comparing PlanetScope and Sentinel-2 Imagery for Mapping Mountain Pines in the Sarntal Alps, Italy by Rösch, Moritz, Sonnenschein, Ruth, Buchelt, Sebastian, Ullmann, Tobias

“…The mountain pine (Pinus mugo ssp. Mugo Turra) is an important component of the alpine treeline ecotone and fulfills numerous ecosystem functions. To…”
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How Phenology Shapes Crop-Specific Sentinel-1 PolSAR Features and InSAR Coherence across Multiple Years and Orbits by Löw, Johannes, Hill, Steven, Otte, Insa, Thiel, Michael, Ullmann, Tobias, Conrad, Christopher

“…Spatial information about plant health and productivity are essential when assessing the progress towards Sustainable Development Goals such as life on land…”
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Spatiotemporal Fusion Modelling Using STARFM: Examples of Landsat 8 and Sentinel-2 NDVI in Bavaria by Dhillon, Maninder Singh, Dahms, Thorsten, Kübert-Flock, Carina, Steffan-Dewenter, Ingolf, Zhang, Jie, Ullmann, Tobias

“…The increasing availability and variety of global satellite products provide a new level of data with different spatial, temporal, and spectral resolutions;…”
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Modelling Crop Biomass from Synthetic Remote Sensing Time Series: Example for the DEMMIN Test Site, Germany by Dhillon, Maninder Singh, Dahms, Thorsten, Kuebert-Flock, Carina, Borg, Erik, Conrad, Christopher, Ullmann, Tobias

“…This study compares the performance of the five widely used crop growth models (CGMs): World Food Studies (WOFOST), Coalition for Environmentally Responsible…”
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Finding karstic caves and rockshelters in the Inner Asian mountain corridor using predictive modelling and field survey by Cuthbertson, Patrick, Ullmann, Tobias, Büdel, Christian, Varis, Aristeidis, Namen, Abay, Seltmann, Reimar, Reed, Denné, Taimagambetov, Zhaken, Iovita, Radu

“…The area of the Inner Asian Mountain Corridor (IAMC) follows the foothills and piedmont zones around the northern limits of Asia's interior mountains,…”
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The Influence of Commuting on Population Exposure to Air Pollution: Toward Global Application With a Proxy on the Degree of Urbanization by Gilardi, Lorenza, Erbertseder, Thilo, Baier, Frank, Paeth, Heiko, Ullmann, Tobias, Taubenbock, Hannes

“…Urban populations are significantly affected by air pollution, which poses a major threat to public health. However, standardized and public mobility data,…”
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Assessing Spatiotemporal Variations of Landsat Land Surface Temperature and Multispectral Indices in the Arctic Mackenzie Delta Region between 1985 and 2018 by Nill, Leon, Ullmann, Tobias, Kneisel, Christof, Sobiech-Wolf, Jennifer, Baumhauer, Roland

“…Air temperatures in the Arctic have increased substantially over the last decades, which has extensively altered the properties of the land surface. Capturing…”
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Evaluation of MODIS, Landsat 8 and Sentinel-2 Data for Accurate Crop Yield Predictions: A Case Study Using STARFM NDVI in Bavaria, Germany by Dhillon, Maninder Singh, Kübert-Flock, Carina, Dahms, Thorsten, Rummler, Thomas, Arnault, Joel, Steffan-Dewenter, Ingolf, Ullmann, Tobias

“…The increasing availability and variety of global satellite products and the rapid development of new algorithms has provided great potential to generate a new…”
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Deciphering Small-Scale Seasonal Surface Dynamics of Rock Glaciers in the Central European Alps Using DInSAR Time Series by Buchelt, Sebastian, Blöthe, Jan Henrik, Kuenzer, Claudia, Schmitt, Andreas, Ullmann, Tobias, Philipp, Marius, Kneisel, Christof

“…The Essential Climate Variable (ECV) Permafrost is currently undergoing strong changes due to rising ground and air temperatures. Surface movement, forming…”
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Correction: Finding karstic caves and rockshelters in the Inner Asian mountain corridor using predictive modelling and field survey by Cuthbertson, Patrick, Ullmann, Tobias, Büdel, Christian, Varis, Aristeidis, Namen, Abay, Seltmann, Reimar, Reed, Denné, Taimagambetov, Zhaken, Iovita, Radu

“…[This corrects the article DOI: 10.1371/journal.pone.0245170.]…”
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Impact of STARFM on Crop Yield Predictions: Fusing MODIS with Landsat 5, 7, and 8 NDVIs in Bavaria Germany by Dhillon, Maninder Singh, Dahms, Thorsten, Kübert-Flock, Carina, Liepa, Adomas, Rummler, Thomas, Arnault, Joel, Steffan-Dewenter, Ingolf, Ullmann, Tobias

“…Rapid and accurate yield estimates at both field and regional levels remain the goal of sustainable agriculture and food security. Hereby, the identification…”
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