Energetics of surface melt in West Antarctica
-
Published:2021-07-26
Issue:7
Volume:15
Page:3459-3494
-
ISSN:1994-0424
-
Container-title:The Cryosphere
-
language:en
-
Short-container-title:The Cryosphere
Author:
Ghiz Madison L., Scott Ryan C.ORCID, Vogelmann Andrew M.ORCID, Lenaerts Jan T. M.ORCID, Lazzara Matthew, Lubin Dan
Abstract
Abstract. We use reanalysis data and satellite remote sensing of cloud properties to examine how meteorological conditions alter the surface energy balance to
cause surface melt that is detectable in satellite passive microwave imagery over West Antarctica. This analysis can detect each of the three
primary mechanisms for inducing surface melt at a specific location: thermal blanketing involving sensible heat flux and/or longwave heating by
optically thick cloud cover, all-wave radiative enhancement by optically thin cloud cover, and föhn winds. We examine case studies over Pine
Island and Thwaites glaciers, which are of interest for ice shelf and ice sheet stability, and over Siple Dome, which is more readily accessible for
field work. During January 2015 over Siple Dome we identified a melt event whose origin is an all-wave radiative enhancement by optically thin
clouds. During December 2011 over Pine Island and Thwaites glaciers, we identified a melt event caused mainly by thermal blanketing from optically
thick clouds. Over Siple Dome, those same 2011 synoptic conditions yielded a thermal-blanketing-driven melt event that was initiated by an impulse
of sensible heat flux and then prolonged by cloud longwave heating. The December 2011 synoptic conditions also generated föhn winds at a location on
the Ross Ice Shelf adjacent to the Transantarctic Mountains, and we analyze this case with additional support from automatic weather station
data. In contrast, a late-summer thermal blanketing period over Pine Island and Thwaites glaciers during February 2013 showed surface melt initiated
by cloud longwave heating and then prolonged by enhanced sensible heat flux. One limitation thus far with this type of analysis involves uncertainties
in the cloud optical properties. Nevertheless, with improvements this type of analysis can enable quantitative prediction of atmospheric stress on
the vulnerable Antarctic ice shelves in a steadily warming climate.
Funder
Science Mission Directorate
Publisher
Copernicus GmbH
Subject
Earth-Surface Processes,Water Science and Technology
Reference83 articles.
1. Adusumilli, S., Fricker, H. A., Medley, B., Padman, L., and Siegfried, M. R.:
Interannual variations in meltwater input to the Southern Ocean from Antarctic ice shelves,
Nat. Geosci.,
13, 616–620, https://doi.org/10.1038/s41561-020-0616-z, 2020. 2. Alley, R. B., Anandakrishnan, S., Christianson, K., Horgan, H. J., Muto, A., Parizek, B. R., Pollard, D., and Walker, R. T.:
Oceanic forcing of ice-sheet retreat: West Antarctica and more,
Annu. Rev. Earth Pl. Sc.,
43, 207–231, https://doi.org/10.1146/annurev-earth-060614-105344, 2015. 3. Bell, R. E., Chu, W., Kingslake, J., Das, I., Tedesco, M., Tinto, K. J., Zappa, C. J., Frezzotti, M., Boghosian, A., and Lee, W. S.:
Antarctic ice shelf potentially stabilized by export of meltwater in surface river,
Nature,
544, 344–351, https://doi.org/10.1038/nature22048, 2017. 4. Bell, R. E., Banwell, A. F., Trusel, L. D., and Kingslake, J.:
Antarctic surface hydrology and impacts on ice-sheet mass balance,
Nat. Clim. Change,
8, 1044–1052, https://doi.org/10.1038/s41558-018-0326-3, 2018. 5. Bennartz, R., Shupe, M. D., Turner, D. D., Walden, V. P., Steffen, K., Cox, C. J., Kulie, M. S., Miller, N. B., and Pettersen, C.:
July 2012 Greenland melt extent enhanced by low-level liquid clouds,
Nature,
496, 83–86, https://doi.org/10.1038/nature12002, 2013.
Cited by
13 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|