2024-03-29T05:25:01Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/817762022-11-17T02:08:08Zhdl_2115_20056hdl_2115_147Mapping of Active Frazil for Antarctic Coastal Polynyas, With an Estimation of Sea-Ice ProductionNakata, K.Ohshima, K. I.Nihashi, S.coastal polynyafrazil iceice typepassive microwavessea ice productionSouthern Ocean450The importance of the area of active frazil and associated high sea-ice production in Antarctic coastal polynyas has been increasingly recognized in recent in situ and high-resolution satellite observations. However, the occurrence and spatial distribution of active-frazil area are not well understood. We present the first mapping of active-frazil area for Antarctic coastal polynyas, based on the thin ice algorithm of AMSR-E that discriminates active-frazil area. Mapping of sea-ice production is presented by taking account of active-frazil area. Active-frazil area is predominant along East Antarctica, particularly very close to the coast, locally leading to very high ice-production rates exceeding 20 m/yr. For frazil-dominant polynyas, estimated ice production is similar to 20%-50% higher compared with previous studies. Analyses of all the major polynyas suggest that active-frazil extent depends on offshore wind and air temperature, while ice production is determined by offshore wind only.American Geophysical UnionJournal Articlehttp://hdl.handle.net/2115/817760094-8276Geophysical research letters486e20202021-03-28enginfo:doi/10.1029/2020GL091353none