Affiliations:
1School of Geography, Planning, and Spatial Science,
University of Tasmania; Hobart 7001, Tasmania, Australia2The Australian Centre for Excellence in Antarctic
Science, University of Tasmania; Hobart 7001, Tasmania, Australia.3State Key Laboratory of Marine Environmental Science,
College of Ocean and Earth Sciences, Xiamen University, Xiamen, China4Centre for
Southern Hemisphere Oceans Research, CSIRO Oceans and Atmosphere;
Hobart, Tasmania, Australia.
*Corresponding author. Email:
Matt.King@utas.edu.au
Abstract: Antarctica has been losing ice mass for decades, but
its link to large-scale climate forcing is not clear. Shorter-period
variability has been partly associated with El NiƱo Southern Oscillation
(ENSO), but a clear connection with the dominant climate mode, the
Southern Annular Mode (SAM), is yet to be found. We show that space
gravimetric estimates of ice-mass variability over 2002-2021 may be
substantially explained by a simple linear relation with detrended,
time-integrated SAM and ENSO indices, from the whole ice sheet down to
individual drainage basins. Approximately 40% of the ice-mass trend can
be ascribed to increasingly persistent positive SAM forcing which, since
the 1940s, is likely due to anthropogenic activity. Similar attribution
over 2002-2021 could connect recent ice-sheet change to human activity.
One-Sentence Summary: Observed decadal variability and change
of Antarctic ice-sheet mass is substantially explained by large-scale
climate modes.