Convection Initiation in Monsoon Coastal Areas (South China)
Convection Initiation in Monsoon Coastal Areas (South China)
复制标题
季风沿海地区（华南）对流启动
DOI：
10.1029/2020gl087035
复制
发表时间：
2020-06-16
影响因子：
5.2
通讯作者：
Huang, Ling
中科院分区：
文献类型：
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作者：
Bai, Lanqiang;Chen, Guixing;Huang, Ling
季风海岸以活跃的对流为特征，但相关的对流启动（CI）特征尚未得到很好的了解。对华南地区高分辨率雷达观测资料的分析表明，CI与季风活动、海陆对比度和海岸地形有明显的依赖关系。季风爆发后CI活动高度活跃，夏季向北扩展。一些CI热点出现在热带岛屿，半岛和沿海山脉的迎风坡。白天CI发生集中在海岸线100公里以内的陆地上。夜间CI最大值位于海岸线和邻近山脉的近海地区。CI显示了离岸传播午夜后降雨前，可能是由于陆地微风或下坡风与日增强陆上季风流的收敛。对CI的进一步了解可能为预报灾害性天气提供额外的好处，因为CI预示了成熟的深对流的发展。
Monsoon coasts are characterized by active convection, but the features of associated convection initiation (CI) are not well understood. An analysis of kilometer-resolution radar observations in South China reveals a distinct dependence of CI on monsoon activity, land-sea contrast, and coastal orography. The CI occurrence becomes highly active after the monsoon onset and extends northward in summer. Several CI hotspots appear on tropical islands, peninsulas, and windward slopes of coastal mountains. Daytime CI occurrences are concentrated on land within 100 km of the coastline. The nocturnal CI maxima are located on coastlines and in the offshore areas with adjacent mountains. CI shows an offshore propagation after midnight prior to rainfall, probably due to the convergence of land breezes or downslope winds with diurnally enhanced onshore monsoon flows. The improved understanding of CI may provide additional benefit for forecasting severe weather because CI foretells the development of full-fledged deep convection.