Climatology and Evolution of the Antarctic Peninsula Föhn Wind-Induced Melt Regime From 1979–2018
Journal Article
·
· Journal of Geophysical Research: Atmospheres
- Univ. of California, Irvine, CA (United States); Univ. of California, Irvine, CA (United States)
- Univ. of California, Irvine, CA (United States)
- Utrecht University (Netherlands)
Warm and dry föhn winds on the Antarctic Peninsula (AP) cause surface melt that can destabilize vulnerable ice shelves. Topographic funneling of these downslope winds through mountain passes and canyons can produce localized wind-induced melt that is difficult to quantify without direct measurements. Our Föhn Detection Algorithm (FöhnDA) identifies the surface föhn signature that causes melt from measurement by 12 Automatic Weather Stations on the AP, that train a machine learning model to detect föhn in 5 km Regional Atmospheric Climate Model 2 (RACMO2.3p2) simulations and in the ERA5 reanalysis model. We estimate the fraction of AP surface melt attributed to föhn and possibly katabatic winds and identify the drivers of melt, temporal variability, and long-term trends and evolution from 1979–2018. We find that föhn wind-induced melt accounts for 3.1% of the total melt on the AP and can be as high at 18% close to the mountains where the winds funnel through mountain canyons. Föhn-induced surface melt does not significantly increase from 1979–2018, despite a warmer atmosphere and more positive Southern Annular Mode. However, a significant increase (+0.1 Gt y-1) and subsequent decrease/stabilization occur in 1979–1998 and 1999–2018, consistent with the AP warming and cooling trends during the same time periods. Föhn occurrence, more than föhn strength, drives the annual variability in föhn-induced melt. Long-term föhn-induced melt trends and evolution are attributable to seasonal changes in föhn occurrence, with increased occurrence in summer, and decreased occurrence in fall, winter, and early spring over the past 20 years.
- Research Organization:
- Univ. of California, Irvine, CA (United States); University of Michigan, Ann Arbor, MI (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- Grant/Contract Number:
- SC0019278
- OSTI ID:
- 1853006
- Journal Information:
- Journal of Geophysical Research: Atmospheres, Journal Name: Journal of Geophysical Research: Atmospheres Journal Issue: 4 Vol. 126; ISSN 2169-897X
- Publisher:
- American Geophysical UnionCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
The role of föhn winds in eastern Antarctic Peninsula rapid ice shelf collapse
Wind‐Associated Melt Trends and Contrasts Between the Greenland and Antarctic Ice Sheets
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt
Journal Article
·
Tue Apr 12 20:00:00 EDT 2022
· The Cryosphere (Online)
·
OSTI ID:1981305
Wind‐Associated Melt Trends and Contrasts Between the Greenland and Antarctic Ice Sheets
Journal Article
·
Mon Aug 28 20:00:00 EDT 2023
· Geophysical Research Letters
·
OSTI ID:2421094
Meteorological Drivers and Large-Scale Climate Forcing of West Antarctic Surface Melt
Journal Article
·
Thu Jan 03 19:00:00 EST 2019
· Journal of Climate
·
OSTI ID:1612800