The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica
Over the perennial sea ice in the western and central Weddell Sea, Antarctica, the onset of summer is accompanied by a significant decrease of sea-ice brightness temperatures (Tb) as observed by passive-microwave radiometers such as the Special Sensor Microwave/Imager (SSM/I). The summer-specific Tb...
Published in: | Annals of Glaciology |
---|---|
Main Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
International Glaciological Society
2006
|
Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/28545/ https://doi.org/10.3189/172756406781811817 |
id |
ftoceanrep:oai:oceanrep.geomar.de:28545 |
---|---|
record_format |
openpolar |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:28545 2023-05-15T13:29:43+02:00 The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica Willmes, Sascha Bareiss, Jörg Haas, Christian Nicolaus, Marcel 2006 https://oceanrep.geomar.de/id/eprint/28545/ https://doi.org/10.3189/172756406781811817 unknown International Glaciological Society Willmes, S., Bareiss, J., Haas, C. and Nicolaus, M. (2006) The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica. Annals of Glaciology, 44 (1). pp. 297-302. DOI 10.3189/172756406781811817 <https://doi.org/10.3189/172756406781811817>. doi:10.3189/172756406781811817 Article PeerReviewed 2006 ftoceanrep https://doi.org/10.3189/172756406781811817 2023-04-07T15:18:57Z Over the perennial sea ice in the western and central Weddell Sea, Antarctica, the onset of summer is accompanied by a significant decrease of sea-ice brightness temperatures (Tb) as observed by passive-microwave radiometers such as the Special Sensor Microwave/Imager (SSM/I). The summer-specific Tb drop is the dominant feature in the seasonal cycle of Tb data and represents a conspicuous difference to most Arctic sea-ice regions, where the onset of summer is mostly marked by a rise in Tb. Data from a 5 week drift station through the western Weddell Sea in the 2004/05 austral summer, Ice Station POLarstern (ISPOL), helped with identifying the characteristic processes for Antarctic sea ice. In situ glaciological and meteorological data, in combination with SSM/I swath satellite data, indicate that the cycle of repeated diurnal thawing and refreezing of snow ('freeze–thaw cycles') is the dominant process in the summer season, with the absence of complete snow wetting. The resulting metamorphous snow with increased grain size, as well as the formation of ice layers, leads to decreasing emissivity, enhanced volume scattering and increased backscatter. This causes the summer Tb drop. Article in Journal/Newspaper Annals of Glaciology Antarc* Antarctic Antarctica Arctic Sea ice Weddell Sea OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic Arctic Austral Weddell Weddell Sea Annals of Glaciology 44 297 302 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
unknown |
description |
Over the perennial sea ice in the western and central Weddell Sea, Antarctica, the onset of summer is accompanied by a significant decrease of sea-ice brightness temperatures (Tb) as observed by passive-microwave radiometers such as the Special Sensor Microwave/Imager (SSM/I). The summer-specific Tb drop is the dominant feature in the seasonal cycle of Tb data and represents a conspicuous difference to most Arctic sea-ice regions, where the onset of summer is mostly marked by a rise in Tb. Data from a 5 week drift station through the western Weddell Sea in the 2004/05 austral summer, Ice Station POLarstern (ISPOL), helped with identifying the characteristic processes for Antarctic sea ice. In situ glaciological and meteorological data, in combination with SSM/I swath satellite data, indicate that the cycle of repeated diurnal thawing and refreezing of snow ('freeze–thaw cycles') is the dominant process in the summer season, with the absence of complete snow wetting. The resulting metamorphous snow with increased grain size, as well as the formation of ice layers, leads to decreasing emissivity, enhanced volume scattering and increased backscatter. This causes the summer Tb drop. |
format |
Article in Journal/Newspaper |
author |
Willmes, Sascha Bareiss, Jörg Haas, Christian Nicolaus, Marcel |
spellingShingle |
Willmes, Sascha Bareiss, Jörg Haas, Christian Nicolaus, Marcel The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica |
author_facet |
Willmes, Sascha Bareiss, Jörg Haas, Christian Nicolaus, Marcel |
author_sort |
Willmes, Sascha |
title |
The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica |
title_short |
The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica |
title_full |
The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica |
title_fullStr |
The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica |
title_full_unstemmed |
The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica |
title_sort |
importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the weddell sea, antarctica |
publisher |
International Glaciological Society |
publishDate |
2006 |
url |
https://oceanrep.geomar.de/id/eprint/28545/ https://doi.org/10.3189/172756406781811817 |
geographic |
Antarctic Arctic Austral Weddell Weddell Sea |
geographic_facet |
Antarctic Arctic Austral Weddell Weddell Sea |
genre |
Annals of Glaciology Antarc* Antarctic Antarctica Arctic Sea ice Weddell Sea |
genre_facet |
Annals of Glaciology Antarc* Antarctic Antarctica Arctic Sea ice Weddell Sea |
op_relation |
Willmes, S., Bareiss, J., Haas, C. and Nicolaus, M. (2006) The importance of diurnal processes for the seasonal cycle of sea-ice microwave brightness temperatures during early summer in the Weddell Sea, Antarctica. Annals of Glaciology, 44 (1). pp. 297-302. DOI 10.3189/172756406781811817 <https://doi.org/10.3189/172756406781811817>. doi:10.3189/172756406781811817 |
op_doi |
https://doi.org/10.3189/172756406781811817 |
container_title |
Annals of Glaciology |
container_volume |
44 |
container_start_page |
297 |
op_container_end_page |
302 |
_version_ |
1766002367444025344 |