TY - JOUR
T1 - Inter-decadal climate variability induces differential ice response along Pacific-facing West Antarctica
AU - Christie, Frazer D. W.
AU - Steig, Eric J.
AU - Gourmelen, Noel
AU - Tett, Simon F. B.
AU - Bingham, Robert G.
N1 - Funding Information:
This study was supported by a Carnegie Trust for the Universities of Scotland Carnegie PhD Scholarship (to F.D.W.C.), hosted in the Edinburgh E3 U.K. Natural Environment Research Council (NERC) Doctoral Training Partnership (NE/L002558/1) and the Scottish Alliance for Geoscience, Environment and Society (SAGES) Graduate School. The study was also produced with the financial assistance of the Prince Albert II of Monaco Foundation (to F.D.W.C.), as well as grants from the NERC / U.S. National Science Foundation (NSF) International Thwaites Glacier Collaboration (Grants NE/S006613, ITGC-GHOST, to R.G.B. and NE/S006796, ITGC-PROPHET, to N.G.; this is ITGC Contribution No. ITGC-088), NSF Grant 2045075 to E.J.S., NERC Grant NE/T001607/1 (QuORUM) to N.G. and S.F.B.T., and European Space Agency funding (Projects 4000128611/19/I‐DT, 4D Antarctica and Digital Twin Antarctica) to N.G. The authors thank I. Joughin for providing access to his TerraSAR-X-derived grounding zone data acquired over Pine Island Glacier (cf. ref. ).
Publisher Copyright:
© 2023, The Author(s).
PY - 2023/1/16
Y1 - 2023/1/16
N2 - West Antarctica has experienced dramatic ice losses contributing to global sea-level rise in recent decades, particularly from Pine Island and Thwaites glaciers. Although these ice losses manifest an ongoing Marine Ice Sheet Instability, projections of their future rate are confounded by limited observations along West Antarctica’s coastal perimeter with respect to how the pace of retreat can be modulated by variations in climate forcing. Here, we derive a comprehensive, 12-year record of glacier retreat around West Antarctica’s Pacific-facing margin and compare this dataset to contemporaneous estimates of ice flow, mass loss, the state of the Southern Ocean and the atmosphere. Between 2003 and 2015, rates of glacier retreat and acceleration were extensive along the Bellingshausen Sea coastline, but slowed along the Amundsen Sea. We attribute this to an interdecadal suppression of westerly winds in the Amundsen Sea, which reduced warm water inflow to the Amundsen Sea Embayment. Our results provide direct observations that the pace, magnitude and extent of ice destabilization around West Antarctica vary by location, with the Amundsen Sea response most sensitive to interdecadal atmosphere-ocean variability. Thus, model projections accounting for regionally resolved ice-ocean-atmosphere interactions will be important for predicting accurately the short-term evolution of the Antarctic Ice Sheet.
AB - West Antarctica has experienced dramatic ice losses contributing to global sea-level rise in recent decades, particularly from Pine Island and Thwaites glaciers. Although these ice losses manifest an ongoing Marine Ice Sheet Instability, projections of their future rate are confounded by limited observations along West Antarctica’s coastal perimeter with respect to how the pace of retreat can be modulated by variations in climate forcing. Here, we derive a comprehensive, 12-year record of glacier retreat around West Antarctica’s Pacific-facing margin and compare this dataset to contemporaneous estimates of ice flow, mass loss, the state of the Southern Ocean and the atmosphere. Between 2003 and 2015, rates of glacier retreat and acceleration were extensive along the Bellingshausen Sea coastline, but slowed along the Amundsen Sea. We attribute this to an interdecadal suppression of westerly winds in the Amundsen Sea, which reduced warm water inflow to the Amundsen Sea Embayment. Our results provide direct observations that the pace, magnitude and extent of ice destabilization around West Antarctica vary by location, with the Amundsen Sea response most sensitive to interdecadal atmosphere-ocean variability. Thus, model projections accounting for regionally resolved ice-ocean-atmosphere interactions will be important for predicting accurately the short-term evolution of the Antarctic Ice Sheet.
U2 - 10.1038/s41467-022-35471-3
DO - 10.1038/s41467-022-35471-3
M3 - Article
SN - 2041-1723
VL - 14
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 93
ER -