The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY (한국해양학회지:바다)

The Korean Society of Oceanography (한국해양학회)
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Intercomparison of the Global Ocean Reanalysis Data

전지구 해양 재분석 자료 비교 분석

  • Chang, You-Soon (Department of Earth Science Education, Kongju National University)
  • 장유순 (공주대학교 지구과학교육과)
  • Received : 2015.02.12
  • Accepted : 2015.05.18
  • Published : 2015.05.31
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Abstract

This study summarized the results of the international ocean reanalysis intercomparison project. We introduced the characteristics of various ocean reanalysis systems and analyzed the assimilated performance on the typical eight oceanic variables (heat content, steric height, sea level, surface heat fluxes, mixed layer depth, subsurface salinity, depth of $20^{\circ}C$ isotherm, sea ice). In general, ensemble means show better estimations than those of any individual ocean reanalysis, but it depends on analyzed regions and variables. Among the eight oceanic variables, salinity and sea ice variabilities have large spreads among models. The deep sea, Southern Ocean, and coastal regions including western boundary current commonly appear as the areas with largest uncertainty between different objective analyses and assimilation models. We expect that intercomparison project for the ocean assimilation models independently operated in Korea should be processed, which allows us to join relevant international programs in the near future.

본 연구에서는 국제 공동 해양 재분석 자료 비교 프로젝트 결과를 요약하였다. 다양한 재분석 자료 생산 시스템의 종류 및 특성을 소개하였으며, 대표적인 8가지 해양 변수(열용량, 열염분 높이, 해수면 높이, 표층 열속, 혼합층 깊이, 아표층염분, $20^{\circ}C$ 등온선 깊이, 해빙)에 대한 전지구 해양 자료 동화 모델 성능을 비교 분석하였다. 일반적으로 단일 재분석 자료 결과보다 앙상블 평균 값이 비교적 높은 성능을 나타내었으나, 검증 변수와 해역에 따라 서로 다른 특징을 보였다. 해양 변수 중에는 염분 및 해빙 변동이 모델간 가장 큰 편차를 보였다. 심층 해역, 남극해, 서안 경계 해역을 포함한 연안역에서는 공통적으로 객관 분석장과 동화 모델간의 편차가 크게 나타났다. 국내에서도 독립적으로 운영되고 있는 해양 자료 동화 모델간의 비교 분석 프로그램이 추진되어, 향후 관련된 국제 공동 연구에 활발히 참여할 수 있는 기회가 확대되기를 기대한다.

Keywords

References

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