Retrieval of wintertime snow depth on Arctic sea ice and analysis of long-term variability using satellite passive measurements

• Main Author: 시호연
• Other Authors: 손병주, Hoyeon Shi, 자연과학대학 지구환경과학부
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 서울대학교 대학원 2021
• Subjects: Snow depth; Arctic sea ice; Satellite Remote Sensing; Climate Change; 적설깊이; 북극 해빙; 인공위성 원격탐사; 기후변화; 550; Arctic; Arctic Ocean; Arctic Basin; Climate change; Sea ice
• Online Access: https://hdl.handle.net/10371/178927; https://dcollection.snu.ac.kr/common/orgView/000000167918

학위논문(박사) -- 서울대학교대학원 : 자연과학대학 지구환경과학부, 2021.8. 손병주. A new satellite retrieval algorithm for wintertime snow depth on Arctic sea ice was developed based on the hydrostatic balance and thermodynamic steady-state of a snow-ice system. In this algorithm, snow depth is estimated from the passive infrared and microwave measurements, with the use of sea ice freeboard, snow surface temperature, and snow-ice interface temperature as inputs. The algorithm was validated against NASA's Operation IceBridge (OIB) measurements, and results indicate that the snow depth on the Arctic sea ice can be estimated with a high level of accuracy. To produce a long-term snow depth record in the Arctic basin-scale, sea ice freeboard was estimated from the satellite passive microwave (PMW) measurements. To do so, the snow-ice scattering optical depth from satellite PMW measurements was used as a predictor for the estimation of the total freeboard. Estimated PMW total freeboards were found to be in good agreement with OIB total freeboards. The wintertime snow depth records for the 2003-2020 period were produced by combining the PMW freeboard and satellite-derived temperatures. It was found that snow depth is highly dependent on sea ice type, likely due to the snow accumulation timing and period. The snow depth and its variability were greater on multiyear ice than on first-year ice. Besides, a significant reduction in mean snow depth was found, compared to the snow depth climatology for the 1954-1991 period. Regarding the temporal variations over the 2003-2020 period, regionally different snow depth trends are found; negative and positive snow depth trends were noted over the eastern and western parts of the Arctic Ocean, respectively. It is thought that the negative trends are related to sea ice type transition and delayed freeze onset, while the positive trends are related to increased precipitation amount. 겨울철 북극 해빙지역 적설깊이 산출을 위해 적설-해빙 시스템의 정역학적 평형 및 열역학적 정상상태(steady state)를 기반으로 한 새로운 인공위성 산출 알고리즘이 개발되었다. 개발된 알고리즘은 수동 마이크로파/적외선 ...