Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies
The surface effective emissivities of Arctic sea ice are calculated using Advanced Microwave Scanning Radiometer 2 (AMSR2) measurements. These emissivities are analyzed for stable winter conditions during the months of January–May and November and December of 2020 for several main sea ice types defi...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-11-01
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| Series: | Remote Sensing |
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| Online Access: | https://www.mdpi.com/2072-4292/14/23/5927 |
| _version_ | 1797462286317649920 |
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| author | Elizaveta Zabolotskikh Sergey Azarov |
| author_facet | Elizaveta Zabolotskikh Sergey Azarov |
| author_sort | Elizaveta Zabolotskikh |
| collection | DOAJ |
| description | The surface effective emissivities of Arctic sea ice are calculated using Advanced Microwave Scanning Radiometer 2 (AMSR2) measurements. These emissivities are analyzed for stable winter conditions during the months of January–May and November and December of 2020 for several main sea ice types defined with the sea ice maps of the Arctic and Antarctic Research Institute (AARI). The sea ice emissivities are derived from the AMSR2 data using the radiation transfer model for a non-scattering atmosphere and ERA5 reanalysis data. The emissivities are analyzed only for areas of totally consolidated sea ice of definite types. Probability distribution functions are built for the emissivities and their functions for such sea ice types as nilas, young ice, thin first-year (FY) ice, medium FY ice, thick FY ice and multi-year ice. The emissivity variations with frequency are estimated for each of the considered sea ice type for all seven months. The variations are calculated both for the emissivities and for their gradients at the AMSR2 channel frequencies. Obtained emissivities turned out to be generally lower than reported previously in scientific studies, whereas the emissivity variability values proved to be much larger than was known before. For all FY ice types, at all the frequencies, an increase in the emissivity at the beginning of winter and its decrease by the end of May are observed. The emissivity gradients demonstrate noticeable decreases with sea ice age, and their values may be used in sea ice classification algorithms based on the AMSR2 data. |
| first_indexed | 2024-03-09T17:34:22Z |
| format | Article |
| id | doaj.art-f8997d07b5884d638aea97a3a5404029 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-09T17:34:22Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-f8997d07b5884d638aea97a3a54040292023-11-24T12:02:45ZengMDPI AGRemote Sensing2072-42922022-11-011423592710.3390/rs14235927Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 FrequenciesElizaveta Zabolotskikh0Sergey Azarov1Satellite Oceanography Laboratory, Russian State Hydrometeorological University, 195196 St. Petersburg, RussiaSatellite Oceanography Laboratory, Russian State Hydrometeorological University, 195196 St. Petersburg, RussiaThe surface effective emissivities of Arctic sea ice are calculated using Advanced Microwave Scanning Radiometer 2 (AMSR2) measurements. These emissivities are analyzed for stable winter conditions during the months of January–May and November and December of 2020 for several main sea ice types defined with the sea ice maps of the Arctic and Antarctic Research Institute (AARI). The sea ice emissivities are derived from the AMSR2 data using the radiation transfer model for a non-scattering atmosphere and ERA5 reanalysis data. The emissivities are analyzed only for areas of totally consolidated sea ice of definite types. Probability distribution functions are built for the emissivities and their functions for such sea ice types as nilas, young ice, thin first-year (FY) ice, medium FY ice, thick FY ice and multi-year ice. The emissivity variations with frequency are estimated for each of the considered sea ice type for all seven months. The variations are calculated both for the emissivities and for their gradients at the AMSR2 channel frequencies. Obtained emissivities turned out to be generally lower than reported previously in scientific studies, whereas the emissivity variability values proved to be much larger than was known before. For all FY ice types, at all the frequencies, an increase in the emissivity at the beginning of winter and its decrease by the end of May are observed. The emissivity gradients demonstrate noticeable decreases with sea ice age, and their values may be used in sea ice classification algorithms based on the AMSR2 data.https://www.mdpi.com/2072-4292/14/23/5927arcticAMSR2emissivitysea ice |
| spellingShingle | Elizaveta Zabolotskikh Sergey Azarov Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies Remote Sensing arctic AMSR2 emissivity sea ice |
| title | Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies |
| title_full | Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies |
| title_fullStr | Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies |
| title_full_unstemmed | Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies |
| title_short | Wintertime Emissivities of the Arctic Sea Ice Types at the AMSR2 Frequencies |
| title_sort | wintertime emissivities of the arctic sea ice types at the amsr2 frequencies |
| topic | arctic AMSR2 emissivity sea ice |
| url | https://www.mdpi.com/2072-4292/14/23/5927 |
| work_keys_str_mv | AT elizavetazabolotskikh wintertimeemissivitiesofthearcticseaicetypesattheamsr2frequencies AT sergeyazarov wintertimeemissivitiesofthearcticseaicetypesattheamsr2frequencies |