Research on the Characteristics of Rainfall in Bangladesh as the cause of heavy flood

点击翻译按钮获取中文摘要

During summer monsoon period, we carried out the upper layer observation in Bangladesh Meteorological Department (BMD) in Dhaka for clarifying the diurnal variation of the rainfall in Bangladesh. The routine observation in BMD is once a day, so we supplied the three radiosonde for extra observation. We collected the surface observation data of BMD for about 50 years for completing the data base of the surface meteorological observation data. We also collecting the four meteorological radar data in Dhaka, Rangpur, Cox's Bazar and Kepuphara. Comparing and integrating these meteorological data, wedevided the characteristics of the precipitation type. In the northeastern area in Sylhet, one of the largest amount of rainfall in the world, the main rainfall occurred in the early morning. On the other hand, the middle of this country, the main rainfall is in the middle of the daytime, especially in the afternoon. This difference is due to the difference of the convective activity in each area of Bangladesh. The quantitative evaluation of the aerial difference is clarified in this research.