積乱雲発達初期の雲情報データ同化によるゲリラ豪雨予測

Abstract

In this study, cloud information in the early developmental stage of guerrilla heavy rainfall is extracted from Himawari-8 and Ka band radar, and an assimilation experiment is conducted. And we will clarify what kind of influence it has on the developmental stage and maturity stage of guerrilla heavy rain. First, the influence of assimilation of cloud information was evaluated using observation system simulation experiment (OSSE). Next, considering the results obtained by OSSE, we calculated the relative humidity from Himawari-8 and the cloud water mixing ratio from Ka band radar, and carried out the assimilation experiment. The relative humidity assimilation has a great influence on the water vapor field of the atmosphere, and the assimilation of cloud water mixing ratio can reproduce the occurrence, development and maintenance of rainfall. For further elucidation of this mechanism, comparison with the assimilation experiment which calculated the rainwater mixing ratio from XRAIN was performed. As a result, the usefulness of the effect of assimilating the cloud water mixing ratio, which is cloud information, was reconfirmed.