基于遥感降水数据的海南岛海陆地降水差异研究——以海南岛为例

Study on Precipitation Differences between Sea and Land in Hainan Island Based on Remotely Sensed Precipitation Data—A Case Study of Hainan Island

海陆降水分布差异是热带海陆气象系统相互作用最显著的现象之一。本研究利用2000至2019年的高分辨率GSMaP遥感降水数据,系统性地分析了中国最大的热带海岛——海南岛及其邻近海域的海陆降水分布特征及其年际和年代际变化。研究显示,海南岛降水分布呈现明显的空间和时间差异,尤其是东部海岸降水量最多,而西部最少。此外,陆地降水普遍多于海洋,特别是在文昌市至万宁市一带。在年际变化方面,海洋和陆地降水变化模式相似,但极值年份不同,其中东南部海岸在2009年和2010年降水量达到峰值。雨季降水主要集中在东南部,而旱季降水较少,且同样呈现东多西少的格局。季节性降水分析表明,降水主要集中在5月至10月,尤其是8月和10月分别是海洋和陆地的降水高峰。此外,不同强度的降水事件主要发生在6月至10月,特别是在9月和10月。在寒潮影响下,冬季降水在北部多于南部,这主要由于冷空气在五指山地区形成静止锋。Differences in sea-land precipitation distribution are one of the most significant phenomena in the interaction of tropical sea-land meteorological systems. This study systematically analyses the characteristics of sea-land precipitation distribution and its interannual and interdecadal variations over Hainan Island, the largest tropical island in China, and its adjacent seas using high-resolution GSMaP remotely sensed precipitation data from 2000 to 2019. The study shows that the precipitation distribution on Hainan Island exhibits obvious spatial and temporal variations, especially on the eastern coast, where precipitation is the highest, and on the western coast, where it is the lowest. In addition, land precipitation is generally more significant than that of the ocean, especially along the area from Wenchang City to Wanning City. In terms of interannual variability, the patterns of ocean and land precipitation changes are similar, but the extreme years are different, with the southeastern coast having peak precipitation in 2009 and 2010. Precipitation in the rainy season is mainly concentrated in the southeast, while precipitation in the dry season is less, and again shows a pattern of more in the east and less in the west. Seasonal precipitation analyses show that precipitation is mainly concentrated from May to October, especially in August and October, which are the peaks of precipitation in the ocean and on land, respectively. In addition, precipitation events of different intensities occur mainly from June to October, especially in September and October. Under the influence of cold waves, winter precipitation is more in the north than in the south, which is mainly due to the formation of stationary fronts by cold air in the Wuzhishan region.