Skip to Main content Skip to Navigation
Journal articles

Rapid change of snow surface properties at Vostok, East Antarctica, revealed by altimetry and radiometry

Pascal Lacroix 1, 2 B. Legresy 1 F. Remy 1 F. Blarel 1 Ghislain Picard 3 Ludovic Brucker 3
1 LEGOS - Laboratoire d'études en Géophysique et océanographie spatiales
2 LGIT - Laboratoire de Géophysique Interne et Tectonophysique
3 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
Abstract : We present results of snow surface properties using the ENVISAT dual frequency altimeter at S (3.2 GHz) and Ku (13.6 GHz) bands and the AMSR-E microwave radiometer at frequencies ranging between 6 and 36 GHz in the Vostok region, East Antarctica. The altimetric time series observed between 2002 and 2008 show variations at 3 different time scales (daily, seasonal and inter-annual), that correlate directly with variations in the snow surface properties. In this study we focus on the analysis of the rapid daily event, occurring on February 14th 2005, that created a jump of the backscatter coefficient of up to 5.3 dB at the S band and 2.5 dB at the Ku band. The ratio of V/H-polarization brightness temperature slowly decreased in December and January 2005, and suddenly increased on February 14th 2005. The origin of this rapid event is investigated using AWS data from Vostok station, altimetric and radiometric data simultaneously. Both snow surface density and roughness are found to vary during this event. This event is shown to be synchronous with strong wind occuring during a period of anomalous wind direction, and the presence of surface hoar. These particular conditions certainly modified the snow surface roughness and thus impacted the altimetric signal. We finally investigate the impact of this event on the calculation of the regional ice-sheet mass-balance using different corrections of height with echo shape variations. It is shown to be negligible only if the full echo shape correction (Legresy et al., 2006) is used.
Keywords : Ice-sheets Microwave Altimetry Radiometry Snow surface properties Mass-balance
Document type :
Journal articles
Complete list of metadatas
https://hal-insu.archives-ouvertes.fr/insu-00497983
Contributor : Aurore Gayraud <>
Submitted on : Tuesday, July 6, 2010 - 12:45:55 PM
Last modification on : Thursday, October 15, 2020 - 3:17:52 AM

Identifiers

Collections

INSU | UNIV-SAVOIE | CNRS | OSUG | UGA | IFSTTAR | LGGE | CRYO | OMP | OMP-LEGOS | UNIV-TLSE3 | IRSTEA | INRAE | METEO

Citation

Pascal Lacroix, B. Legresy, F. Remy, F. Blarel, Ghislain Picard, et al.. Rapid change of snow surface properties at Vostok, East Antarctica, revealed by altimetry and radiometry. Remote Sensing of Environment, Elsevier, 2009, 113 (12), pp.2633-2641. ⟨10.1016/j.rse.2009.07.019⟩. ⟨insu-00497983⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

397