A5030117080- Climate variability and models
- Hydrology and Watershed Management Studies
- Flood Risk Assessment and Management
- Geophysics and Gravity Measurements
- Meteorological Phenomena and Simulations
- Atmospheric and Environmental Gas Dynamics
- Oceanographic and Atmospheric Processes
- Water resources management and optimization
- Cryospheric studies and observations
- Hydrological Forecasting Using AI
- Arctic and Antarctic ice dynamics
- Climate change and permafrost
- Soil Moisture and Remote Sensing
- GNSS positioning and interference
- Solar and Space Plasma Dynamics
- Precipitation Measurement and Analysis
- Soil Geostatistics and Mapping
- Hydrology and Drought Analysis
- Reservoir Engineering and Simulation Methods
- Urban Heat Island Mitigation
- Atmospheric Ozone and Climate
- Plant Water Relations and Carbon Dynamics
- Synthetic Aperture Radar (SAR) Applications and Techniques
- Lung Cancer Treatments and Mutations
- Geophysical and Geoelectrical Methods
Observatoire de Paris
2018-2024
Laboratoire d’Etudes du Rayonnement et de la Matière en Astrophysique et Atmosphères
2018-2024
Centre National de la Recherche Scientifique
2020-2024
Sorbonne Université
2020-2024
The University of Tokyo
2021-2023
Université Paris Sciences et Lettres
2020
Centre National de Recherches Météorologiques
2019
Roche (France)
2018
Abstract As the largest river basin on Earth, Amazon is of major importance to world's climate and water resources. Over past decades, advances in satellite‐based remote sensing (RS) have brought our understanding its terrestrial cycle associated hydrological processes a new era. Here, we review studies various techniques using satellite RS Amazon. We show how played role supporting research key findings regarding cycle, region became laboratory for groundbreaking investigations retrievals...
ABSTRACT Life on Earth vitally depends the availability of water. Human pressure freshwater resources is increasing, as human exposure to weather-related extremes (droughts, storms, floods) caused by climate change. Understanding these changes pivotal for developing mitigation and adaptation strategies. The Global Climate Observing System (GCOS) defines a suite essential variables (ECVs), many related water cycle, required systematically monitor Earth’s system. Since long-term observations...
Abstract. The Mediterranean region is one of the climate hotspots where change impacts are both pronounced and documented. HyMeX (Hydrometeorological eXperiment) aims to improve our understanding water cycle from meteorological scales. However, monitoring with Earth observations (EO) still a challenge: EO products multiple, their utility degraded by large uncertainties incoherences among products. Over region, these difficulties exacerbated coastal/mountainous regions small size hydrological...
One expectation for the SWOT (Surface Water and Ocean Topography) satellite is that it can provide information on surface waters, including beneath clouds possibly vegetation, at high spatial resolution which optical sensors cannot achieve. However, observation errors do exist, e.g., due to specular reflection. It necessary filter these errors. Those amount up 44% of considered pixels in this study. They drastically limits use data. Consequently, filtered need be filled some way, obtain...
The event runoff coefficient (i.e. the ratio between and precipitation that originated runoff) is a key factor for understanding basin response to events. Runoff depends on intensity duration but also specific geohydrology attributes (including soil type, geology, land cover, topography ) last not least, antecedent (or pre-storm) conditions (i.e., amount of water stored in different hydrological compartments, like river, groundwater, snowpack). relation pre-storm critical flood forecasting,...
Over the last 25 years, Arctic sea ice has seen its extent decline dramatically. Passive microwave observations, with their ability to penetrate clouds and independency sunlight, have been used provide concentration (SIC) measurements since 1970s. The Copernicus Imaging Microwave Radiometer (CIMR) is a high priority candidate mission within European Expansion program, special focus on observation of polar regions. It will observe at 6.9 10.65 GHz 15 km spatial resolution, 18.7 36.5 5...
Abstract. The three infrared atmospheric sounding interferometers (IASIs), launched in 2006, 2012, and 2018, are key instruments to weather forecasting, most meteorological centres assimilate IASI nadir radiance data into models feed their forecasts. European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) recently released a reprocessed homogeneous record whole observation period, from which 13 years (2008–2020) temperature profiles can be obtained. In this work,...
Abstract. The total water storage change (TWSC) over land is a major component of the global cycle, with large influence on climate variability, sea level budget and resource availability for human life. Its first estimates at scale were made available GRACE (Gravity Recovery Climate Experiment) observations 2002–2016 period, followed since 2018 by launch GRACE-FO (Follow-On) mission. In this paper, using an approach based mass conservation rule, we propose to merge satellite-based...
The infrared atmospheric sounder interferometer (IASI) onboard the Metop-A and Metop-B satellites is an essential instrument for numerical weather prediction centers. IASI, with its 8461 channels, enables observation of surface geophysical variables twice a day around world. This data volume will increase in future, stressing need practical efficient dimension reduction techniques storage transmission but also inversion or assimilation. In previous paper by Aires <italic...
With the increasing volume of satellite observations, dimension reduction techniques are more and important for storage or transmission. Furthermore, they essential inversion schemes that, in practice, cannot handle huge amount information provided by modern instruments near‐real‐time inversion. In this article, we compare theoretical advantages limitations two general strategies: compression (i.e. feature extraction) channel selection selection). The statistical ‘input variable selection’...
Earth and Space Science Open Archive This work has been accepted for publication in Reviews of Geophysics. Version RecordESSOAr is a venue early communication or feedback before peer review. Data may be preliminary. Learn more about preprints. preprintOpen AccessYou are viewing the latest version by default [v1]Amazon hydrology from space: scientific advances future challengesAuthorsAlice CésarFassoni-AndradeiDAyan SantosFleischmanniDFabricePapaiDRodrigo Cauduro Dias...
Abstract A multitude of Earth observation (EO) products are available for monitoring the terrestrial water cycle. These EO datasets have resulted in a multiplicity same geophysical variable. Furthermore, inconsistencies between components prevent budget closure. maximum posteriori (MAP) estimator has been used past to optimally combine datasets. This framework many advantages, but it can only be utilized when all four (precipitation P , evapotranspiration E total storage change dS and river...
Abstract Multilayer perceptrons have been popular in the remote‐sensing community for last 30 years, particular infrared atmospheric sounding interferometer instrument. However, coarse‐resolution instruments such as interferometer, these algorithms are currently used at pixel level and trained a global scale. This can result regional biases that not only affect quality of retrieval but potentially also propagate into model forecasts if results were to be assimilated. To help reduce biases,...
Abstract Monitoring coherently the Amazon Water Cycle (WC) using satellite observations is crucial for climate and water resources studies. The SAtellite (SAWC) integration methodology introduced to optimize datasets. In this paper, WC budget balanced simultaneously over 10 sub‐basins by constraining horizontal exchanges between them. Compared an actual assimilation analysis, SAWC benefits from use of storage Gravity Recovery Climate Experiment. corrects evapotranspiration datasets that tend...
Abstract In companion paper 1, the SAtellite Water Cycle (SAWC) satellite data set integration approach was presented. SAWC accounts for (1) closure of water budget at sub‐basin scale by (2) using upstream/downstream dependencies. Here, database is used to reconstruct a missing component. The total storage change ( dS ) can be reconstructed prior Gravity Recovery and Climate Experiment (GRACE) period. terms seasonal interannual variations, provides long‐term estimates that are highly...
Neural networks (NNs) are becoming increasingly more popular to interpret remote sensing observations in many contexts. Their flexibility and accuracy have been a true advantage for the retrieval of geophysical variables atmosphere, land, ocean, over last three decades. Uncertainty retrieved products is important assess quality retrievals but also combine <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a posteriori</i> , them complex way...
In the first article of this series, two classical strategies to reduce satellite data dimension (i.e. compression and channel selection) were presented, together with introduction a new method, so‐called ‘bottleneck channels’ (BC). BC are compromise between approaches can benefit from advantages both. article, three methodologies tested using experiments on synthetic dataset corresponding hyperspectral conceptual instrument in microwave, for frequencies up 500 GHz. As expected, principal...
Triple collocation (TC)-based methods have become popular to estimate the uncertainty of many geophysical variables retrieved from satellite observations. The true advantage these is that no ground-based truth required and they can thus be applied on a global scale. So far, TC-based been limited STandard Deviation (STD) at grid These estimates represent an overall STD error for precipitation products over each grid. Such information useful investigate sources errors such as topography or...
A new methodology has been described in Kilic et al. (Ice Concentration Retrieval from the Analysis of Microwaves: New Methodology Designed for Copernicus Imaging Microwave Radiometer, Remote Sensing 2020, 12, 1060, Part 1 this study) to estimate Sea Ice (SIC) satellite passive microwave observations between 6 and 36 GHz. The Microwaves (IceCREAM) algorithm is based on an optimal estimation, with a simple radiative transfer model derived at 0% 100% SIC. Observations low high frequencies have...
Abstract. Integration techniques are used to combine Earth Observation (EO) datasets study the Water Cycle (WC). By merging several datasets, they reduce uncertainty and introduce coherency among them. Several EO integration methods presented compared: The Optimal Selection (OS) simply choses best individual datasets. Simple Weighting (SW) is a weighted sum of uncertainties. Three other closure-constraint on WC budget: (1) SW plus Post-Filtering (PF) very efficient but it applied at...
Abstract Estimating river discharge Q at global scale from satellite observations is not yet fully satisfactory in part because of limited space/time resolution. Furthermore, on highly anthropized basins, it essential to anchor the analysis reliable measurements. Gauge networks are however very sparse and time, SWOT (Surface Water Ocean Topography) estimates available. The method proposed here able obtain continuous daily 1 km/daily resolution, using indirect data ground-based estimates. We...
The 4DMED-Hydrolog ESA project aims at developing a high-resolution (1km) and consistent reconstruction of the Mediterranean terrestrial water cycle by using latest Earth Observation (EO) products. We exploit here synergy between available EOs to better estimate components (i.e., precipitation P, evaporation E, storage dS river discharge RD). obtained, more accurate, representation our environment is intended feed decision support systems, in changing climate, for resilient society. Among...