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利用热带测雨计划卫星上的测雨雷达得到的降水资料,对1998年东亚降水,特别是中国大陆东部、东海和南海的降水,进行了分析研究,并对比了热带降水研究结果.年统计结果表明,东亚地区层状云降水出现概率极高(比面积达83.7%),对流云降水的比面积仅占13.6%,然而两者对总降水量的贡献相当.结果还表明,暖对流云降水出现的比例和对总降水量的贡献很小.在季节尺度,对流云和层状云降水的比与两者的面积比成比例关系.除夏季外,测雨雷达降水量与GPCP降水量可比性好.研究结果还指出:在中纬度陆地和海洋上对流云和层状云的比降水量和比面积呈相反方向作季节性南北移动,这一活动与东亚季风变化一致:该地区降水的季节性变化还表现为降水垂直廓线的变化.除冬季外,南海地区降水垂直结构呈热带特征.CRAD分析表明,对流云降水的地面雨强变化大,尤其在陆地上,而层状云多表现为地面弱降水.“,”Precipitation radar data derived from the Tropical Rainfall Measuring Mission (TRMM) satelliteare used to study precipitation characteristics in 1998 over East Asia (10°-38°N, 100°-145°E), especiallyover mid-latitude land (continental land) and ocean (East China Sea and South China Sea). Results arecompared with precipitations in the tropics. Yearly statistics show dominant stratiform rain events overEast Asia (about 83.7% by area fraction) contributing to 50% of the total precipitation. Deep convectiverains contribute 48% to the total precipitation with a 13.7% area fraction. The statistics also show theunimportance of warm convective rain in East Asia, contributing 1.5% to the total precipitation with a2.7% area fraction. On a seasonal scale, the results indicate that the rainfall ratio of stratiform rain todeep convective rain is proportional to their rainfall pixel ratio. Seasonal precipitation patterns comparewell between Global Precipitation Climatology Project rainfall and TRMM PR measurements except insummer. Studies indicate a clear opposite shift of rainfall amount and events between deep convective andstratiform rains in the meridional in East Asia, which corresponds to the alternative activities of summermonsoon and winter monsoon in the region. The vertical structures of precipitation also exhibit strongseasonal variability in precipitation Contoured Rainrate by Altitude Diagrams (CRADs) and mean profilesin the mid-latitudes of East Asia. However, these structures in the South China Sea are of a tropical typeexcept in winter. The analysis of CRADs reveals a wide range of surface rainfall rates for most deepconvective rains, especially in the continental land, and light rain rate for most stratiform rains in EastAsia, regardless of over land or ocean.