Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature
Antarctic surface snowmelt is sensitive to the polar climate. The ascending and descending passes of the Advanced Microwave Scanning Radiometer for Earth Observing System Sensor (AMSR-E) observed the Antarctic ice sheet in the afternoon (the warmest period) and at midnight (a cold period), enabling...
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ftdoajarticles:oai:doaj.org/article:8c0ae060162749e59f856da56500872f 2023-05-15T14:01:44+02:00 Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature Lei Zheng Chunxia Zhou Ruixi Liu Qizhen Sun 2018-08-01T00:00:00Z https://doi.org/10.3390/rs10091391 https://doaj.org/article/8c0ae060162749e59f856da56500872f EN eng MDPI AG http://www.mdpi.com/2072-4292/10/9/1391 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs10091391 https://doaj.org/article/8c0ae060162749e59f856da56500872f Remote Sensing, Vol 10, Iss 9, p 1391 (2018) Antarctica snowmelt AMSR-E MEMLS Science Q article 2018 ftdoajarticles https://doi.org/10.3390/rs10091391 2022-12-31T16:19:37Z Antarctic surface snowmelt is sensitive to the polar climate. The ascending and descending passes of the Advanced Microwave Scanning Radiometer for Earth Observing System Sensor (AMSR-E) observed the Antarctic ice sheet in the afternoon (the warmest period) and at midnight (a cold period), enabling us to make full use of the diurnal amplitude variations (DAV) in brightness temperature (Tb) to detect snowmelt. The DAV in vertically polarized 36.5 GHz Tb (DAV36V) is extremely sensitive to liquid water and can reduce the effects of the structural changes in snowpacks during melt seasons. A set of controlled experiments based on the microwave emission model of layered snow (MEMLS) were conducted to study the changes of the vertically polarized 36.5 GHz Tb (Δ36V) during the transitions from dry to wet snow regimes. Results of the experiments suggest that 9 K can be used as a DAV36V threshold to recognize snowmelt. The analyses of snowmelt suggest that the Antarctic ice sheet began to melt in November and became almost completely frozen in late March of the following year. The total cumulative melt area from 2002 to 2011 was 2.44 × 106 km2, i.e., 17.58% of the Antarctic ice sheet. The annual cumulative melt area showed considerable fluctuations, with a significant (above 90% confidence level) drop of 5.24 × 104 km2/year in the short term. Persistent snowmelt (i.e., melt that continues for at least three days) detected by AMSR-E and hourly air temperatures (Tair) were very consistent. Though melt seasons became longer in the western Antarctic Peninsula and the Shackleton Ice Shelf, Antarctica was subjected to considerable decreases in duration and melting days in stable melt areas, i.e., −0.64 and −0.81 days/year, respectively. Surface snowmelt in Antarctica decreased temporally and spatially from 2002 to 2011. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelf Shackleton Ice Shelf Directory of Open Access Journals: DOAJ Articles Antarctic The Antarctic Antarctic Peninsula Shackleton Shackleton Ice Shelf ENVELOPE(100.504,100.504,-65.996,-65.996) Remote Sensing 10 9 1391 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Antarctica snowmelt AMSR-E MEMLS Science Q |
spellingShingle |
Antarctica snowmelt AMSR-E MEMLS Science Q Lei Zheng Chunxia Zhou Ruixi Liu Qizhen Sun Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature |
topic_facet |
Antarctica snowmelt AMSR-E MEMLS Science Q |
description |
Antarctic surface snowmelt is sensitive to the polar climate. The ascending and descending passes of the Advanced Microwave Scanning Radiometer for Earth Observing System Sensor (AMSR-E) observed the Antarctic ice sheet in the afternoon (the warmest period) and at midnight (a cold period), enabling us to make full use of the diurnal amplitude variations (DAV) in brightness temperature (Tb) to detect snowmelt. The DAV in vertically polarized 36.5 GHz Tb (DAV36V) is extremely sensitive to liquid water and can reduce the effects of the structural changes in snowpacks during melt seasons. A set of controlled experiments based on the microwave emission model of layered snow (MEMLS) were conducted to study the changes of the vertically polarized 36.5 GHz Tb (Δ36V) during the transitions from dry to wet snow regimes. Results of the experiments suggest that 9 K can be used as a DAV36V threshold to recognize snowmelt. The analyses of snowmelt suggest that the Antarctic ice sheet began to melt in November and became almost completely frozen in late March of the following year. The total cumulative melt area from 2002 to 2011 was 2.44 × 106 km2, i.e., 17.58% of the Antarctic ice sheet. The annual cumulative melt area showed considerable fluctuations, with a significant (above 90% confidence level) drop of 5.24 × 104 km2/year in the short term. Persistent snowmelt (i.e., melt that continues for at least three days) detected by AMSR-E and hourly air temperatures (Tair) were very consistent. Though melt seasons became longer in the western Antarctic Peninsula and the Shackleton Ice Shelf, Antarctica was subjected to considerable decreases in duration and melting days in stable melt areas, i.e., −0.64 and −0.81 days/year, respectively. Surface snowmelt in Antarctica decreased temporally and spatially from 2002 to 2011. |
format |
Article in Journal/Newspaper |
author |
Lei Zheng Chunxia Zhou Ruixi Liu Qizhen Sun |
author_facet |
Lei Zheng Chunxia Zhou Ruixi Liu Qizhen Sun |
author_sort |
Lei Zheng |
title |
Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature |
title_short |
Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature |
title_full |
Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature |
title_fullStr |
Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature |
title_full_unstemmed |
Antarctic Snowmelt Detected by Diurnal Variations of AMSR-E Brightness Temperature |
title_sort |
antarctic snowmelt detected by diurnal variations of amsr-e brightness temperature |
publisher |
MDPI AG |
publishDate |
2018 |
url |
https://doi.org/10.3390/rs10091391 https://doaj.org/article/8c0ae060162749e59f856da56500872f |
long_lat |
ENVELOPE(100.504,100.504,-65.996,-65.996) |
geographic |
Antarctic The Antarctic Antarctic Peninsula Shackleton Shackleton Ice Shelf |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula Shackleton Shackleton Ice Shelf |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelf Shackleton Ice Shelf |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelf Shackleton Ice Shelf |
op_source |
Remote Sensing, Vol 10, Iss 9, p 1391 (2018) |
op_relation |
http://www.mdpi.com/2072-4292/10/9/1391 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs10091391 https://doaj.org/article/8c0ae060162749e59f856da56500872f |
op_doi |
https://doi.org/10.3390/rs10091391 |
container_title |
Remote Sensing |
container_volume |
10 |
container_issue |
9 |
container_start_page |
1391 |
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1766271770529103872 |