Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt
Understanding the drivers of surface melting in West Antarctica is crucial for understanding future ice loss and global sea level rise. This study identifies atmospheric drivers of surface melt on West Antarctic ice shelves and ice sheet margins and relationships with tropical Pacific and high-latit...
Published in: | Journal of Climate |
---|---|
Main Authors: | , , , , |
Language: | unknown |
Published: |
2021
|
Subjects: | |
Online Access: | http://www.osti.gov/servlets/purl/1612800 https://www.osti.gov/biblio/1612800 https://doi.org/10.1175/jcli-d-18-0233.1 |
id |
ftosti:oai:osti.gov:1612800 |
---|---|
record_format |
openpolar |
spelling |
ftosti:oai:osti.gov:1612800 2023-07-30T03:56:04+02:00 Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt Scott, Ryan C. Nicolas, Julien P. Bromwich, David H. Norris, Joel R. Lubin, Dan 2021-11-15 application/pdf http://www.osti.gov/servlets/purl/1612800 https://www.osti.gov/biblio/1612800 https://doi.org/10.1175/jcli-d-18-0233.1 unknown http://www.osti.gov/servlets/purl/1612800 https://www.osti.gov/biblio/1612800 https://doi.org/10.1175/jcli-d-18-0233.1 doi:10.1175/jcli-d-18-0233.1 79 ASTRONOMY AND ASTROPHYSICS 2021 ftosti https://doi.org/10.1175/jcli-d-18-0233.1 2023-07-11T09:41:23Z Understanding the drivers of surface melting in West Antarctica is crucial for understanding future ice loss and global sea level rise. This study identifies atmospheric drivers of surface melt on West Antarctic ice shelves and ice sheet margins and relationships with tropical Pacific and high-latitude climate forcing using multidecadal reanalysis and satellite datasets. Physical drivers of ice melt are diagnosed by comparing satellite-observed melt patterns to anomalies of reanalysis near-surface air temperature, winds, and satellite-derived cloud cover, radiative fluxes, and sea ice concentration based on an Antarctic summer synoptic climatology spanning 1979–2017. Summer warming in West Antarctica is favored by Amundsen Sea (AS) blocking activity and a negative phase of the southern annular mode (SAM), which both correlate with El Niño conditions in the tropical Pacific Ocean. Extensive melt events on the Ross–Amundsen sector of the West Antarctic Ice Sheet (WAIS) are linked to persistent, intense AS blocking anticyclones, which force intrusions of marine air over the ice sheet. Surface melting is primarily driven by enhanced downwelling longwave radiation from clouds and a warm, moist atmosphere and by turbulent mixing of sensible heat to the surface by föhn winds. Since the late 1990s, concurrent with ocean-driven WAIS mass loss, summer surface melt occurrence has increased from the Amundsen Sea Embayment to the eastern Ross Ice Shelf. We link this change to increasing anticyclonic advection of marine air into West Antarctica, amplified by increasing air–sea fluxes associated with declining sea ice concentration in the coastal Ross–Amundsen Seas. Other/Unknown Material Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Ice Shelves Ross Ice Shelf Sea ice West Antarctica SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Amundsen Sea Antarctic Pacific Ross Ice Shelf West Antarctic Ice Sheet West Antarctica Journal of Climate 32 3 665 684 |
institution |
Open Polar |
collection |
SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
79 ASTRONOMY AND ASTROPHYSICS |
spellingShingle |
79 ASTRONOMY AND ASTROPHYSICS Scott, Ryan C. Nicolas, Julien P. Bromwich, David H. Norris, Joel R. Lubin, Dan Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt |
topic_facet |
79 ASTRONOMY AND ASTROPHYSICS |
description |
Understanding the drivers of surface melting in West Antarctica is crucial for understanding future ice loss and global sea level rise. This study identifies atmospheric drivers of surface melt on West Antarctic ice shelves and ice sheet margins and relationships with tropical Pacific and high-latitude climate forcing using multidecadal reanalysis and satellite datasets. Physical drivers of ice melt are diagnosed by comparing satellite-observed melt patterns to anomalies of reanalysis near-surface air temperature, winds, and satellite-derived cloud cover, radiative fluxes, and sea ice concentration based on an Antarctic summer synoptic climatology spanning 1979–2017. Summer warming in West Antarctica is favored by Amundsen Sea (AS) blocking activity and a negative phase of the southern annular mode (SAM), which both correlate with El Niño conditions in the tropical Pacific Ocean. Extensive melt events on the Ross–Amundsen sector of the West Antarctic Ice Sheet (WAIS) are linked to persistent, intense AS blocking anticyclones, which force intrusions of marine air over the ice sheet. Surface melting is primarily driven by enhanced downwelling longwave radiation from clouds and a warm, moist atmosphere and by turbulent mixing of sensible heat to the surface by föhn winds. Since the late 1990s, concurrent with ocean-driven WAIS mass loss, summer surface melt occurrence has increased from the Amundsen Sea Embayment to the eastern Ross Ice Shelf. We link this change to increasing anticyclonic advection of marine air into West Antarctica, amplified by increasing air–sea fluxes associated with declining sea ice concentration in the coastal Ross–Amundsen Seas. |
author |
Scott, Ryan C. Nicolas, Julien P. Bromwich, David H. Norris, Joel R. Lubin, Dan |
author_facet |
Scott, Ryan C. Nicolas, Julien P. Bromwich, David H. Norris, Joel R. Lubin, Dan |
author_sort |
Scott, Ryan C. |
title |
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt |
title_short |
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt |
title_full |
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt |
title_fullStr |
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt |
title_full_unstemmed |
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt |
title_sort |
meteorological drivers and large-scale climate forcing of west antarctic surface melt |
publishDate |
2021 |
url |
http://www.osti.gov/servlets/purl/1612800 https://www.osti.gov/biblio/1612800 https://doi.org/10.1175/jcli-d-18-0233.1 |
geographic |
Amundsen Sea Antarctic Pacific Ross Ice Shelf West Antarctic Ice Sheet West Antarctica |
geographic_facet |
Amundsen Sea Antarctic Pacific Ross Ice Shelf West Antarctic Ice Sheet West Antarctica |
genre |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Ice Shelves Ross Ice Shelf Sea ice West Antarctica |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Ice Shelf Ice Shelves Ross Ice Shelf Sea ice West Antarctica |
op_relation |
http://www.osti.gov/servlets/purl/1612800 https://www.osti.gov/biblio/1612800 https://doi.org/10.1175/jcli-d-18-0233.1 doi:10.1175/jcli-d-18-0233.1 |
op_doi |
https://doi.org/10.1175/jcli-d-18-0233.1 |
container_title |
Journal of Climate |
container_volume |
32 |
container_issue |
3 |
container_start_page |
665 |
op_container_end_page |
684 |
_version_ |
1772810792222064640 |