Article
Geochemistry & Geophysics
Thorben Doehne, Martin Horwath, Andreas Groh, Eric Buchta
Summary: This study focuses on the second step of mass change estimation, which involves the analysis of spherical harmonic (SH) input datasets to obtain mass change estimates. The use of sensitivity kernels is proposed as a means to communicate, assess, and compare methods of mass change estimation.
JOURNAL OF GEODESY
(2023)
Article
Engineering, Civil
Bao Zhang, Yibin Yao, Yulin He
Summary: This study evaluated different methods to fill the data gap in Greenland and its six sub-regions, with the results showing that the BPNN method outperformed others, especially in terms of accuracy for the whole of Greenland, helping to re-estimate the ice mass change in the region.
JOURNAL OF HYDROLOGY
(2022)
Article
Environmental Sciences
Peisi Shang, Xiaoli Su, Zhicai Luo
Summary: The mass change patterns of the Greenland ice sheet (GrIS), a major contributor to global mean sea-level rise, have been studied using Gravity Recovery and Climate Experiment (GRACE)/GRACE Follow-On (GRACE-FO) gravimetry data. The results show that mass gain occurs mainly in winter and spring, while mass loss is dominant in summer. The study also reveals an increasing frequency of spring mass loss since 2015 and a higher occurrence of autumn mass gain after 2014. Both mass gain and mass loss show a slightly increasing trend during 2003-2020, potentially in response to ongoing Arctic warming.
Article
Meteorology & Atmospheric Sciences
Diandong Ren, Lance M. Leslie, Ying Huang, Aixue Hu
Summary: The 15-year GRACE data sets show a spurious decreasing trend in global total mass, with Greenland Ice Sheet contributing significantly to the error. By analyzing the mass variation over the GrIS and rectifying the measurements, researchers found a more accurate global mass loss rate estimate for 2002-2015. The study also indicates an increase in the non-tidal Earth moment of inertia due to water redistribution and other effects from a warming climate.
Article
Geochemistry & Geophysics
Chen Wei, Zhong Min, Feng Wei, Wang ChangQing, Li WenHao, Liang Lei
Summary: The IPCC's SROCC report identifies Antarctica and Greenland ice sheets as major contributors to global sea-level rise. This study fills the data gap between GRACE and GRACE-FO missions using the Swarm satellite mission and ARIMA-MC method, and determines the ice mass variations in Antarctica and Greenland during this gap. The results show significant ice mass loss rates in both regions, with some areas experiencing accelerated loss rate in different periods.
CHINESE JOURNAL OF GEOPHYSICS-CHINESE EDITION
(2022)
Article
Geosciences, Multidisciplinary
Lei Wang, James L. Davis, Ian M. Howat
Summary: The Antarctic Ice Sheet (AIS) is a major contributor to global sea-level change, and its mass balance variability on different scales highlights the need to include stochastic processes in loss rate estimates. Loss from the West AIS shows a multidecadal trend, while variations in the East AIS are dominated by short-term accumulation changes. The analysis shows unexpected high variability in mass-loss rates from all sectors, emphasizing the importance of considering time-dependent parameters in projecting future ice sheet changes.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Ziyun Wang, Bao Zhang, Yibin Yao, Wei Zhang
Summary: Significant progress has been made in understanding ice loss in Greenland, but current studies lack a comprehensive understanding of long-term trends and the effects of atmospheric forcing. To address these limitations, a piecewise trajectory model was proposed to detect breaking points and estimate optimal segmented trends. The results showed a deceleration of ice loss in east Greenland from 2012.6 to 2021 compared to 2002-2012.6. The deceleration was mainly due to increased precipitation associated with the positive North Atlantic Oscillation (NAO) phase. The findings suggest that future positive NAO trends may lead to increased precipitation and the preservation of ice in east Greenland.
REMOTE SENSING OF ENVIRONMENT
(2023)
Article
Environmental Sciences
Zhenxiang Fang, Ninglian Wang, Yuwei Wu, Yujie Zhang
Summary: Accurate monitoring of surface temperature and melting on the Greenland Ice Sheet is crucial for understanding its mass balance and climate change. A study using MODIS data found that there is a strong correlation between surface temperature and mass balance of the ice sheet.
Article
Engineering, Aerospace
Jiangjun Ran, Natthachet Tangdamrongsub, Xiaoyun Wan
Summary: This study analyzes the impact of four different error variance-covariance matrix structures on mass transport estimates in Greenland based on monthly GRACE solutions, finding that the diagonal structure obtains the best estimates for recovering the long-term trend. The study also highlights the importance of considering mascon model deficiencies and the release of block diagonal structures for the GRACE Follow-On mission.
ADVANCES IN SPACE RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
Sebastian B. Simonsen, Valentina R. Barletta, William T. Colgan, Louise Sandberg Sorensen
Summary: The study presents the first record of Greenland Ice Sheet mass balance from 1992 to 2020 using multisatellite Ku-band altimetry. It shows that the majority of the ice sheet contribution occurred after 2003, and that 2017 was the first year in the 21st century when the GrIS was in balance within uncertainties. The 28-year radar-derived mass balance record highlights the potential of the method to provide operational mass balance estimates using multisatellite Ku-band altimetry.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Karina Hansen, Martin Truffer, Andy Aschwanden, Kenneth Mankoff, Michael Bevis, Angelika Humbert, Michiel R. van den Broeke, Brice Noel, Anders Bjork, William Colgan, Kurt H. Kjaer, Surendra Adhikari, Valentina Barletta, Shfaqat A. Khan
Summary: This study introduces a novel method for estimating dynamic ice loss of Greenland's three largest outlet glaciers. It reveals a time lag between glacier speedup/slowdown and dynamic thinning/thickening, with the ability to predict speedup/slowdown up to 10.4 months in advance for Jakobshavn Isbr AE. The methodology and results could be important for understanding short-term dynamic fluctuations of outlet glaciers in Greenland.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Chaoyang Zhang, C. K. Shum, Ales Bezdek, Michael Bevis, Joao de Teixeira da Encarnacao, Byron D. Tapley, Yu Zhang, Xiaoli Su, Qiang Shen
Summary: GRACE observations showed a sudden halt in rapid mass loss of the West Antarctic Ice Sheet in 2015, followed by a lower rate until 2017. Swarm gravimetry data efficiently filled the gap in GRACE observations and revealed the return of rapid mass loss in WAIS during the GRACE intermission. Changes in precipitation patterns driven by climate cycles further explain the dramatic shifts in mass loss regime observed by Swarm.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geosciences, Multidisciplinary
Wenshan Wang, Charles S. Zender, Dirk van As, Robert S. Fausto, Matthew K. Laffin
Summary: The Greenland Ice Sheet is the primary source of global Barystatic sea-level rise, with at least half of its recent mass loss acceleration caused by surface meltwater runoff. Decade-long measurements from automatic weather stations in the most melt-susceptible regions identified dominant energy components and associated physical processes for surface mass loss. Surprisingly, large melt events only contribute 2% to total surface melt since 2007, with day-to-day variability dominated by sensible heat exchange and shortwave radiation.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
Riley Culberg, Dustin M. Schroeder, Gregor Steinbrugge
Summary: The formation mechanism of double ridges on Europa remains unclear. This study analyzes landforms on the Greenland Ice Sheet and suggests that the refreezing of shallow water sills may be responsible for the formation of these ridges. The findings indicate that the same process might be widespread across Europa's ice shell.
NATURE COMMUNICATIONS
(2022)
Article
Geosciences, Multidisciplinary
Matthew K. Laffin, Charles S. Zender, Melchior van Wessem, Brice Noel, Wenshan Wang
Summary: This study uses climate model simulations to analyze the trends in downslope winds and associated melt on the Greenland and Antarctic ice sheets since 1960. The results show that downslope wind significantly affects surface melt on both ice sheets. The study also reveals a decrease in wind-associated melt on the Antarctic ice sheet, while an increase is observed on the Greenland ice sheet.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Ibrahim Fayad, Nicolas Baghdadi, Frederic Frappart
Summary: This study validates the water level estimates from GEDI against in situ gauge station records and analyzes the factors affecting the accuracy. Results show that using viewing angle as a filtering criterion is the best compromise between retained shot count and water level estimation accuracy. V2 provides elevations with a more constant but higher bias compared to V1.
Article
Environmental Sciences
Lucia Seoane, Guillaume Ramillien, Benjamin Beirens, Jose Darrozes, Didier Rouxel, Thierry Schmitt, Corinne Salauen, Frederic Frappart
Summary: In this study, an iterative Extended Kalman Filter approach was used to recover the topographic heights of an undersea volcanic mount using gravity measurements at sea surface. The method showed good accuracy in estimating the topography, especially when regional compensation was considered. However, larger discrepancies were found in the seamount flanks due to missing high-resolution information.
Article
Environmental Sciences
Catherine Prigent, Carlos Jimenez, Lan Anh Dinh, Frederic Frappart, Pierre Gentine, Jean-Pierre Wigneron, Joseph Munchak
Summary: This study documents the variability of tropical forest structure and function using satellite observations from GPM, analyzing the seasonal and diurnal cycles of microwave data for the first time. The analysis reveals diurnal patterns in backscatter and emissivity, with differing behaviors during the dry season in the southeastern Amazonian forest.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
Article
Environmental Sciences
Xiaojun Li, Jean-Pierre Wigneron, Lei Fan, Frederic Frappart, Simon H. Yueh, Andreas Colliander, Ardeshir Ebtehaj, Lun Gao, Roberto Fernandez-Moran, Xiangzhuo Liu, Mengjia Wang, Hongliang Ma, Christophe Moisy, Philippe Ciais
Summary: Passive microwave remote sensing at L-band provides an unprecedented opportunity to estimate global surface soil moisture and vegetation water content. This study presents a new algorithm (SMAP-IB) to retrieve soil moisture and L-band vegetation optical depth from SMAP radiometric observations. The results suggest that SMAP-IB performs well in capturing the temporal trends of in-situ observations and exhibits good correlation with aboveground biomass and tree height.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Environmental Sciences
Ibrahim Fayad, Nicolas Baghdadi, Jean-Stephane Bailly, Frederic Frappart, NUria Pantaleoni Reluy
Summary: The GEDI LiDAR on the International Space Station has acquired a significant amount of shots globally, which could provide a database for measuring and monitoring inland water levels. However, the accuracy of GEDI elevation estimates is found to be lower than radar or LiDAR altimeters. This study aims to post-process the original GEDI water level estimates using an error model that considers instrumental, atmospheric, and lakes surface state factors, leading to reduced errors in elevation estimation.
Article
Multidisciplinary Sciences
Heidi Kreibich, Anne F. Van Loon, Kai Schroeter, Philip J. Ward, Maurizio Mazzoleni, Nivedita Sairam, Guta Wakbulcho Abeshu, Svetlana Agafonova, Amir AghaKouchak, Hafzullah Aksoy, Camila Alvarez-Garreton, Blanca Aznar, Laila Balkhi, Marlies H. Barendrecht, Sylvain Biancamaria, Liduin Bos-Burgering, Chris Bradley, Yus Budiyono, Wouter Buytaert, Lucinda Capewell, Hayley Carlson, Yonca Cavus, Anais Couasnon, Gemma Coxon, Ioannis Daliakopoulos, Marleen C. de Ruiter, Claire Delus, Mathilde Erfurt, Giuseppe Esposito, Didier Francois, Frederic Frappart, Jim Freer, Natalia Frolova, Animesh K. Gain, Manolis Grillakis, Jordi Oriol Grima, Diego A. Guzman, Laurie S. Huning, Monica Ionita, Maxim Kharlamov, Dao Nguyen Khoi, Natalie Kieboom, Maria Kireeva, Aristeidis Koutroulis, Waldo Lavado-Casimiro, Hong-Yi Li, Maria Carmen LLasat, David Macdonald, Johanna Mard, Hannah Mathew-Richards, Andrew McKenzie, Alfonso Mejia, Eduardo Mario Mendiondo, Marjolein Mens, Shifteh Mobini, Guilherme Samprogna Mohor, Viorica Nagavciuc, Thanh Ngo-Duc, Thi Thao Nguyen Huynh, Pham Thi Thao Nhi, Olga Petrucci, Hong Quan Nguyen, Pere Quintana-Segui, Saman Razavi, Elena Ridolfi, Jannik Riegel, Md Shibly Sadik, Elisa Savelli, Alexey Sazonov, Sanjib Sharma, Johanna Sorensen, Felipe Augusto Arguello Souza, Kerstin Stahl, Max Steinhausen, Michael Stoelzle, Wiwiana Szalinska, Qiuhong Tang, Fuqiang Tian, Tamara Tokarczyk, Carolina Tovar, Thi Van Thu Tran, Marjolein H. J. Van Huijgevoort, Michelle T. H. van Vliet, Sergiy Vorogushyn, Thorsten Wagener, Yueling Wang, Doris E. Wendt, Elliot Wickham, Long Yang, Mauricio Zambrano-Bigiarini, Gunter Bloschl, Giuliano Di Baldassarre
Summary: Risk management can reduce the impacts of floods and droughts, but faces difficulties in managing unprecedented events of a greater magnitude. Improved risk management and integrated management can help lower the impacts of more hazardous events.
Article
Environmental Sciences
Zhilan Zhou, Lei Fan, Gabrielle De Lannoy, Xiangzhuo Liu, Jian Peng, Xiaojing Bai, Frederic Frappart, Nicolas Baghdadi, Zanpin Xing, Xiaojun Li, Mingguo Ma, Xin Li, Tao Che, Liying Geng, Jean-Pierre Wigneron
Summary: This study retrieved high-resolution VOD from C-band Sentinel-1 backscatter data over a grassland in northwestern China, showing large spatial variability and seasonal changes in VOD estimates, with strong correlations with optical vegetation indices.
Article
Environmental Sciences
Binh Pham-Duc, Frederic Frappart, Quan Tran-Anh, Son Tong Si, Hien Phan, Son Nguyen Quoc, Anh Pham Le, Bach Do Viet
Summary: This study estimates the monthly variation of surface water volume in Thac Mo hydroelectric reservoir in South Vietnam using Sentinel-1 observations and Jason-3 altimetry data. The results show a high correlation between surface water extent and water level, as well as between different satellite observations and in situ measurements. The study highlights the importance of using satellite data for monitoring lakes' water storage.
Article
Remote Sensing
Minh-Cuong Ha, Jose Darrozes, Muriel Llubes, Manuela Grippa, Guillaume Ramillien, Frederic Frappart, Frederic Baup, Hakan Torbern Tagesson, Eric Mougin, Idrissa Guiro, Laurent Kergoat, Huu Duy Nguyen, Lucia Seoane, Gregory Dufrechou, Phuong-Lan Vu
Summary: With population growth, water resources will increase significantly in the coming decades. Accurate soil moisture monitoring is essential for optimizing agricultural water use. Recent GNSS-R studies use navigation signals emitted by the GNSS constellations to track changes in soil moisture. However, during drought periods, the penetration of GNSS waves into the soil reduces the accuracy of surface moisture measurements.
EUROPEAN JOURNAL OF REMOTE SENSING
(2022)
Editorial Material
Geosciences, Multidisciplinary
Frederic Frappart, Venkatesh M. M. Merwade
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Hui Yang, Philippe Ciais, Frederic Frappart, Xiaojun Li, Martin Brandt, Rasmus Fensholt, Lei Fan, Sassan Saatchi, Simon Besnard, Zhu Deng, Simon Bowring, Jean-Pierre Wigneron
Summary: Changes in terrestrial carbon storage under environmental and land-use changes are crucial for regional and global carbon budgets. This study used L-band microwave vegetation optical depth to generate global maps of annual live vegetation biomass, and found that boreal and temperate forests contribute the most to the global carbon sink, while wet tropical forests serve as small carbon sources. Additionally, the study revealed that tropical deforested and degraded old-growth forests are nearly carbon neutral, while young and middle-aged forests in temperate and boreal regions are the largest sinks.
Article
Environmental Sciences
Lien Rodriguez-Lopez, David Bustos Usta, Iongel Duran-Llacer, Lisandra Bravo Alvarez, Santiago Yepez, Luc Bourrel, Frederic Frappart, Roberto Urrutia
Summary: In this study, machine learning and remote sensing techniques were combined to estimate chlorophyll-a concentration in a freshwater ecosystem in Southern Chile. The study found that the SARIMAX, LSTM, and RNN models effectively predicted the presence of algae in water bodies, with the LSTM model performing the best.
Article
Environmental Sciences
Leonardo Gutierrez, Adrian Huerta, Evelin Sabino, Luc Bourrel, Frederic Frappart, Waldo Lavado-Casimiro
Summary: This study evaluates the performance of the RE and ED datasets in soil erosion estimation models in Peru and finds that estimating with observed-corrected satellite data is more effective. The study also presents the average annual RE for Peru and identifies the spatial distribution of erosion risk areas.
Proceedings Paper
Geography, Physical
Pierre Zeiger, Frederic Frappart, Jose Darrozes
Summary: This study analyzes the potential of using GNSS Reflectometry (GNSS-R) based on observations from the CYGNSS mission to map flood dynamics in the pan-tropical area. The study shows that CYGNSS observations can effectively detect flooded areas and there is a strong correspondence between the GNSS-R parameters and the percentage of flooded areas. However, there are limitations in high-elevation areas and densely vegetated regions.
XXIV ISPRS CONGRESS: IMAGING TODAY, FORESEEING TOMORROW, COMMISSION III
(2022)
Article
Geosciences, Multidisciplinary
Benjamin Kitambo, Fabrice Papa, Adrien Paris, Raphael M. Tshimanga, Stephane Calmant, Ayan Santos Fleischmann, Frederic Frappart, Melanie Becker, Mohammad J. Tourian, Catherine Prigent, Johary Andriambeloson
Summary: This study analyzes a large record of in situ and satellite-derived observations to characterize the hydroclimatic characteristics of the Congo River basin. The results provide valuable information for hydrological modeling and studying hydrological processes in the region.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
