Open AccessGeodetic measurements of vertical crustal velocity in West Antarctica and the implications for ice mass balance
Author(s) -
Bevis Michael,
Kendrick Eric,
Smalley Robert,
Dalziel Ian,
Caccamise Dana,
Sasgen Ingo,
Helsen Michiel,
Taylor F. W.,
Zhou Hao,
Brown Abel,
Raleigh David,
Willis Michael,
Wilson Terry,
Konfal Stephanie
Publication year - 2009
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2009gc002642
Subject(s) - geology , geodetic datum , peninsula , geodesy , global positioning system , bedrock , post glacial rebound , ice sheet , ice stream , climatology , geomorphology , cryosphere , sea ice , geography , telecommunications , archaeology , computer science
We present preliminary geodetic estimates for vertical bedrock velocity at twelve survey GPS stations in the West Antarctic GPS Network, an additional survey station in the northern Antarctic Peninsula, and eleven continuous GPS stations distributed across the continent. The spatial pattern of these velocities is not consistent with any postglacial rebound (PGR) model known to us. Four leading PGR models appear to be overpredicting uplift rates in the Transantarctic Mountains and West Antarctica and underpredicting them in the peninsula north of 65°. This discrepancy cannot be explained in terms of an elastic response to modern ice loss (except, perhaps, in part of the peninsula). Therefore, our initial geodetic results suggest that most GRACE ice mass rate estimates, which are critically dependent on a PGR correction, are systematically biased and are overpredicting ice loss for the continent as a whole.