Snow melting bias in microwave mapping of Antarctic snow accumulation

O. Magand (1) , G. Picard (1) , L. Brucker (1) , M. Fily (1) , C. Genthon (1)

1 LGGE - Laboratoire de glaciologie et géophysique de l'environnement

Satellite records of microwave surface emission have been used to interpolate in-situ observations of Antarctic surface mass balance (SMB) and build continental-scale maps of accumulation. Using a carefully screened subset of accumulation measurements in the 90°–180° E sector, we show a reasonable agreement with microwave-based accumulation map in the dry-snow regions, but large discrepancies in the coastal regions where melt occurs during summer. Using an emission microwave model, we explain the failure of microwave sensors to retrieve accumulation by the presence of layers created by melt/re-freeze cycles. We conclude that regions potentially affected by melting should be masked-out in microwave-based interpolation schemes.

Domaines: Interfaces continentales, environnement; Océan, Atmosphère; Sciences de la Terre

O. Magand, G. Picard, L. Brucker, M. Fily, C. Genthon. Snow melting bias in microwave mapping of Antarctic snow accumulation. The Cryosphere Discussions, 2008, 2 (2), pp.255-273. ⟨hal-00331155⟩