HR: 1340h
AN: C23A-1151    [Abstracts]
TI: Surface mass balance of the Wilkes and Victoria Land region (90-180°E), East Antarctica, from 1950 to 2005
AU: * Magand, O
EM: magand@lgge.obs.ujf-grenoble.fr
AF: Laboratoire de Glaciologie et Géophysique de l'Environnement, 54 Rue Moliere BP 96, St Martin d'Heres, 38402 France
AU: Genthon, C
EM: genthon@lgge.obs.ujf-grenoble.fr
AF: Laboratoire de Glaciologie et Géophysique de l'Environnement, 54 Rue Moliere BP 96, St Martin d'Heres, 38402 France
AU: Frezzotti, M
EM:
AF: ENEA, CRE Casaccia, Via Anguillarese 301, Roma, 00060 Italy
AU: Ekaykin, A
EM:
AF: AARI, 38 Bering str., St Petersburg, 199397 Russian Federation
AU: Fily, M
EM: fily@lgge.obs.ujf-grenoble.fr
AF: Laboratoire de Glaciologie et Géophysique de l'Environnement, 54 Rue Moliere BP 96, St Martin d'Heres, 38402 France
AB: Based on thousands of field measurements and using improved interpolation techniques, the evaluation of the mean Antarctic Surface Mass Balance (SMB) was recently [Vaughan, et al., 1999] increased by 15% compared to accepted estimates [Giovinetto and Bentley, 1985], with differences exceeding 50% at drainage basin scales. Recent re-calculations of the Antarctic SMB [Giovinetto and Zwally, 2000], using essentially the same field data but applying different sorting and interpolation techniques, appear to agree better with [Vaughan, et al., 1999] than with the older evaluations. However, they still differ by as much as 30% at drainage basin scales, and even by 15% at the scale of East Antarctica as a whole [Rignot and Thomas, 2002]. Obviously, the current uncertainty on the SMB of Antarctica still needs to be reduced. In spite of more than 2000 reported field measurements [Giovinetto and Zwally, 2000], there are 3 major difficulties to building an accurate observation-based full map of the Antarctic SMB. 1) Depending on measurement technique and time sampling, the reliability, accuracy and representativeness of a given data is highly variable and may be very poor; 2) There are still huge gaps in the spatial coverage of the available measurements, and much of the Antarctic SMB estimation currently relies on interpolation; 3) Various measurements sample and various time periods are time-inconsistent, so that real temporal variability can induce spurious spatial variability. The primary goal of the present study is to provide a SMB data analysis that is, as much as possible, spatially and temporally representative of the Mass Balance occurring in the Antarctic sector of 90-180° E from 1950 to 2005. The previous database gathered published SMB data with few or no review about the reliability and validity of all the proposed values. The resulting SMB database for this sector is significantly different from the previously published compilations in [Vaughan, et al., 1999] and [Giovinetto and Zwally, 2000], since it is based on a selection of existing SMB data following specific quality control criteria that are discussed. Moreover, the addition of new results provided by the Italian and French ITASE activities in East Wilkes Land (1998-2001) [Frezzotti and Flora, 2002a] ; [Frezzotti, et al., 2004] ; [Magand, et al., 2005], as well as recent data from the Russian Antarctic Expeditions [Ekaykin, et al., 2002; Ekaykin, et al., 2005] and the Australian National Antarctic Research Expeditions in East Antarctica [Smith, et al., 2002] ; [Goodwin, et al., 2003], improve the data set.
DE: 0762 Mass balance (1218, 1223)
DE: 1621 Cryospheric change (0776)
DE: 9310 Antarctica (4207)
SC: Cryosphere [C]
MN: Fall Meeting 2005