Evaluation of CloudSat snowfall rate profiles by a comparison with in situ micro-rain radar observations in East Antarctica

The Cryosphere Discussions

Madeleine, Jean-Baptiste^1¹  Berne, Alexis^4²  Palerme, Cyril^3³  Durán-Alarcón, Claudio^2⁴  Claud, Chantal^1⁵  Genthon, Christophe^1⁶  Lemonnier, Florentin^1⁷ 

[1]CNRS, Institut des Géosciences de l'Environnement, Université Grenoble Alpes, Grenoble, France^2

[2]Centre for Environmental and Marine Studies, Department of Physics, University of Aveiro, Aveiro, Portugal^7

[3]Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison, Madison, Wisconsin, USA^6

[4]Department of Earth and Environmental Sciences, KU Leuven – University of Leuven, Heverlee, Belgium^5

[5]Development Centre for Weather Forecasting, Norwegian Meteorological Institute, Oslo, Norway^3

[6]Environmental Remote Sensing Laboratory, Environmental Engineering Institute, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland^4

[7]Laboratoire de Météorologie dynamique, Sorbonne Université, École normale supérieure, PSL Research University,École polytechnique, CNRS, LMD/IPSL, 75005 Paris, France^1

DOI  :  10.5194/tc-13-943-2019

学科分类：地球科学(综合)

来源: Copernicus Publications

【 摘 要 】

The Antarctic continent is a vast desert and is the coldest and the most unknown area on Earth. It contains the Antarctic ice sheet, the largest continental water reservoir on Earth that could be affected by the current global warming, leading to sea level rise. The only significant supply of ice is through precipitation, which can be observed from the surface and from space. Remote-sensing observations of the coastal regions and the inner continent using CloudSat radar give an estimated rate of snowfall but with uncertainties twice as large as each single measured value, whereas climate models give a range from half to twice the space–time-averaged observations. The aim of this study is the evaluation of the vertical precipitation rate profiles of CloudSat radar by comparison with two surface-based micro-rain radars (MRRs), located at the coastal French Dumont d'Urville station and at the Belgian Princess Elisabeth station located in the Dronning Maud Land escarpment zone. This in turn leads to a better understanding and reassessment of CloudSat uncertainties. We compared a total of four precipitation events, two per station, when CloudSat overpassed within 10 km of the station and we compared these two different datasets at each vertical level. The correlation between both datasets is near-perfect, even though climatic and geographic conditions are different for the two stations. Using different CloudSat and MRR vertical levels, we obtain 10 km space-scale and short-timescale (a few seconds) CloudSat uncertainties from −13 % up to +22 %. This confirms the robustness of the CloudSat retrievals of snowfall over Antarctica above the blind zone and justifies further analyses of this dataset.

【 授权许可】

CC BY