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KIAPS 전지구 수치예보모델 시스템에서 SAPHIR 자료동화 효과

Impact of SAPHIR Data Assimilation in the KIAPS Global Numerical Weather Prediction System

  • 이시혜 ((재) 한국형예보모델개발사업단) ;
  • 전형욱 ((재) 한국형예보모델개발사업단) ;
  • 송효종 ((재) 한국형예보모델개발사업단)
  • Lee, Sihye (Korea Institute of Atmospheric Prediction Systems) ;
  • Chun, Hyoung-Wook (Korea Institute of Atmospheric Prediction Systems) ;
  • Song, Hyo-Jong (Korea Institute of Atmospheric Prediction Systems)
  • 투고 : 2018.03.05
  • 심사 : 2018.05.23
  • 발행 : 2018.06.30

초록

The KIAPS global model and data assimilation system were extended to assimilate brightness temperature from the Sondeur $Atmosph{\acute{e}}rique$ du Profil $d^{\prime}Humidit{\acute{e}}$ Intertropicale par $Radiom{\acute{e}}trie$ (SAPHIR) passive microwave water vapor sounder on board the Megha-Tropiques satellite. Quality control procedures were developed to assess the SAPHIR data quality for assimilating clear-sky observations over the ocean, and to characterize observation biases and errors. In the global cycle, additional assimilation of SAPHIR observation shows globally significant benefits for 1.5% reduction of the humidity root-mean-square difference (RMSD) against European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecast System (IFS) analysis. The positive forecast impacts for the humidity and temperature in the experiment assimilating SAPHIR were predominant at later lead times between 96- and 168-hour. Even though its spatial coverage is confined to lower latitudes of $30^{\circ}S-30^{\circ}N$ and the observable variable is humidity, the assimilation of SAPHIR has a positive impact on the other variables over the mid-latitude domain. Verification showed a 3% reduction of the humidity RMSD with assimilating SAPHIR, and moreover temperature, zonal wind and surface pressure RMSDs were reduced up to 3%, 5% and 7% near the tropical and mid-latitude regions, respectively.

키워드

참고문헌

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