A5056367901- Cryospheric studies and observations
- Atmospheric and Environmental Gas Dynamics
- Meteorological Phenomena and Simulations
- Climate variability and models
- Arctic and Antarctic ice dynamics
- Geology and Paleoclimatology Research
- Climate change and permafrost
- Atmospheric chemistry and aerosols
- Polar Research and Ecology
- Aeolian processes and effects
- Atmospheric aerosols and clouds
- Winter Sports Injuries and Performance
- Methane Hydrates and Related Phenomena
- Landslides and related hazards
- Atmospheric Ozone and Climate
- Precipitation Measurement and Analysis
- Isotope Analysis in Ecology
- Aerospace Engineering and Energy Systems
- Oceanographic and Atmospheric Processes
- Plant Water Relations and Carbon Dynamics
- Geophysics and Gravity Measurements
- Radioactivity and Radon Measurements
- Air Quality and Health Impacts
- Ocean Acidification Effects and Responses
- Adaptive optics and wavefront sensing
Centre National de la Recherche Scientifique
2015-2024
École Polytechnique
2018-2024
Laboratoire de Météorologie Dynamique
2018-2024
Sorbonne Université
2018-2024
École Normale Supérieure - PSL
2018-2023
Université Paris Sciences et Lettres
2018-2023
Institut Pierre-Simon Laplace
2020-2023
Institut Polytechnique de Paris
2020-2023
Université Grenoble Alpes
2009-2019
Institut de Recherche pour le Développement
2017-2019
The East Antarctic Ice Sheet is the largest, highest, coldest, driest, and windiest ice sheet on Earth. Understanding of surface mass balance (SMB) Antarctica necessary to determine present state sheet, make predictions its potential contribution sea level rise, past history for paleoclimatic reconstructions. However, SMB values are poorly known because logistic constraints in extreme polar environments, they represent one biggest challenges science. Snow accumulation most important...
Core Ideas OZCAR is a network of sites studying the critical zone. covers various disciplines. will help disciplines to work together for better representation and modeling The French zone initiative, called (Observatoires de la Zone Critique–Application et Recherche or Critical Observatories–Application Research) National Research Infrastructure (RI). OZCAR‐RI instrumented sites, bringing 21 pre‐existing research observatories monitoring different compartments situated between “the rock...
On average, the models in Fifth Climate Model Intercomparison Project archive predict an increase Antarctic precipitation from 5.5 to 24.5 % between 1986–2005 and 2080–2099, depending on greenhouse gas emissions scenarios. This translates into a moderation of future sea level rise ranging −19 −71 mm 2006 2099. However, comparison with CloudSat ERA-Interim data show that almost all overestimate current precipitation, some by more than 100 %. If only agree within 20 error are considered,...
Simulations of 222 Rn and other short‐lived tracers are used to evaluate intercompare the representations convective synoptic processes in 20 global atmospheric transport models. Results show that most established three‐dimensional models simulate vertical mixing troposphere within constraints offered by observed mean concentrations subgrid parameterization convection is essential for this purpose. However, none captures variability upper troposphere, reproduces high measured at 200 hPa over...
Abstract. Climate models predict Antarctic precipitation to increase during the 21st century, but their present day differs. A model-independent climatology of characteristics, such as snowfall rates and frequency, is needed assess models, it not yet available. Satellite observations by active sensors has been possible in polar regions since launch CloudSat 2006. Here, we use two products generate first multi-year, precipitation. The product used determine frequency phase precipitation,...
Snowfall in Antarctica is a key term of the ice sheet mass budget that influences sea level at global scale. Over continental margins, persistent katabatic winds blow all year long and supply lower troposphere with unsaturated air. We show this dry air leads to significant low-level sublimation snowfall. found using unprecedented data collected over 1 on coast Adélie Land simulations from different atmospheric models accounts for 17% reduction total snowfall continent up 35% margins East...
Investigation of meteorological measurements along a 45 m tower at Dome C on the high East Antarctic Plateau revealed two distinct stable boundary layer (SBL) regimes this location. The first regime is characterized by strong winds and continuous turbulence. It results in full vertical coupling temperature, wind magnitude direction SBL. second weak winds, associated with turbulent activity very temperature inversions reaching up to 25 K lowest 10 m. Vertical profiles are generally...
Abstract. Water stable isotopes in central Antarctic ice cores are critical to quantify past temperature changes. Accurate reconstructions require one understand the processes controlling surface snow isotopic composition. Isotopic fractionation occurring atmosphere and snowfall composition well understood theoretically implemented atmospheric models. However, post-deposition poorly documented understood. To quantitatively interpret of water archived cores, it is thus essential study...
Abstract. The first results of a campaign intensive observation precipitation in Dumont d'Urville, Antarctica, are presented. Several instruments collected data from November 2015 to February 2016 or longer, including polarimetric radar (MXPol), Micro Rain Radar (MRR), weighing gauge (Pluvio2), and Multi-Angle Snowflake Camera (MASC). These the ground-based measurements region Adélie Land (Terre Adélie), microphysics. Microphysical observations during austral summer 2015/2016 showed that,...
Abstract. The oldest ice core records are obtained from the East Antarctic Plateau. Water isotopes key proxies to reconstructing past climatic conditions over sheet and at evaporation source. accuracy of climate reconstructions depends on knowledge all processes affecting water vapour, precipitation snow isotopic compositions. Fractionation well understood can be integrated in trajectory-based Rayleigh distillation isotope-enabled models. However, a quantitative understanding potentially...
Abstract While most precipitation in Antarctica falls as snow, little is known about liquid precipitation, although it can have ecological and climatic impacts. This study combines meteorological reports at 10 stations with the ERA5 reanalysis to provide a climatological characterization of rainfall occurrence over Antarctica. Along East Antarctic coast, occurs 22 days per year coincides maritime intrusions blocking anticyclones. Over north‐western Peninsula, more than 50 on average recent...
Abstract Between 15 and 19 March 2022, East Antarctica experienced an exceptional heat wave with widespread 30°–40°C temperature anomalies across the ice sheet. This record-shattering event saw numerous monthly records being broken including a new all-time record of −9.4°C on 18 at Concordia Station despite typically transition month to Antarctic coreless winter. The driver for these extremes was intense atmospheric river advecting subtropical/midlatitude moisture deep into interior. scope...
Abstract Between 15 and 19 March 2022, East Antarctica experienced an exceptional heat wave with widespread 30°–40°C temperature anomalies across the ice sheet. In Part I, we assessed meteorological drivers that generated intense atmospheric river (AR) caused these record-shattering anomalies. Here, continue our large collaborative study by analyzing diverse impacts driven AR landfall. These included rain surface melt was recorded along coastal areas, but this outweighed high snowfall...
The density and range of observations made by meteorological stations is insufficient to fully characterize decadal climate variability in Antarctica. Satellite-borne instruments, which offer a high spatial temporal information, can contribute complementary data for characterizing Antarctic change. Here, partial melting snow, significantly affects the microwave emissivity surface, identified counted over 18 yr 20-yr period 1980–99. cumulated product surface area affected duration event,...
A high resolution GCM is used to examine the effect of changes in local surface climate parameters on ice sheets that can influence interpretation isotopic signal from deep cores. The model suggests 10°C difference between LGM temperature deduced borehole thermometry and water isotope analysis a great extent may be due modification precipitation seasonality central Greenland. For East Antarctica, tends suggest weak opposite bias.
We report on results from a World Climate Research Program workshop representations ofscavenging and deposition processes in global transport models of the atmosphere. 15 modelswere evaluated by comparing simulations radon, lead, sulfur dioxide, sulfate against eachother, observations these constituents. This paper provides survey simulationdifferences between models. It identifies circumstances where are consistent withobservations or with each other, they differ other. Thecomparison shows...
We report on results from a World Climate Research Program workshop representations of scavenging and deposition processes in global transport models the atmosphere.15 were evaluated by comparing simulations radon, lead, sulfur dioxide, sulfate against each other, observations these constituents.This paper provides survey simulation differences between models.It identifies circumstances where are consistent with or they differ other.The comparison shows that most able to simulate seasonal...
Abstract A new physically based distributed surface mass-balance model is presented for Alpine glaciers. Based on the Crocus prognostic snow model, it resolves both temporal (1 hour time-step) and spatial (200 m grid-step) variability of energy mass balance Mass-balance reconstructions period 1981–2004 are produced using meteorological reconstruction from SAFRAN Glacier de Saint-Sorlin d’Argentière, French Alps. Both glaciers lost at an accelerated rate in last 23 years. The distribution...
Abstract An updated compilation of published and new data major-ion (Ca, Cl, K, Mg, Na, NO 3 , SO 4 ) methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, United Kingdom, States programme Finland. The comparison shows that chemistry vary up to four orders magnitude across Antarctica exhibit distinct...
Six levels of meteorological sensors have been deployed along a 45 m tower at the French‐Italian Concordia station, Dome C, Antarctic. We present measurements vertical profiles, diurnal cycle, and interdiurnal variability temperature, humidity, wind speed direction for 3 weeks during southern summer 2008. These are compared to 6‐hourly European Center Medium‐Range Forecasts (ECMWF) analyses daily radiosoundings. The ECMWF show 3–4°C warm bias relative observations. They reproduce cycle...
The Concordiasi project is making innovative observations of the atmosphere above Antarctica. most important goals are as follows: To enhance accuracy weather prediction and climate records in Antarctica through assimilation situ satellite data, with an emphasis on data provided by hyperspectral infrared sounders. focus clouds, precipitation, mass budget ice sheets. improvements dynamical model analyses forecasts will be used chemical-transport models that describe links between polar vortex...
The lower atmospheric boundary layer at Dome C on the Antarctic plateau has been continuously monitored along a 45‐m tower since 2009. Two years of observations (2009 and 2010) are presented. A strong diurnal cycle is observed near surface in summer but almost disappears top tower, indicating that nocturnal inversion very shallow. Very steep inversions reaching 1 °C m −1 average winter. They stronger more frequent during colder 2010 winter, maximum ~10–15 above surface. Winter temperature...