查看文章

The precipitation over eastern China during January–March 2010 exhibited a marked intraseasonal oscillation (ISO) and a dominant period of 10-60 days. There were two active intraseasonal rainfall periods. The physical mechanisms responsible for the onset of the two rainfall events were investigated using ERA-interim data. In the first ISO event, anomalous ascending motion was triggered by vertically integrated (1000–300 hPa) warm temperature advection. In addition to southerly anomalies on the intraseasonal (10–60-day) timescale, synoptic-scale southeasterly winds helped advect warm air from the South China Sea and western Pacific into the rainfall region. In the second ISO event, anomalous convection was triggered by a convectively unstable stratification, which was caused primarily by anomalous moisture advection in the lower troposphere (1000–850 hPa) from the Bay of Bengal and the Indo-China …