资源环境科技发展态势分析平台

Following the description of the basic climatic characteristics of Meiyu in East Asia, we present a comprehensive review of multi-time scale variabilities of the Meiyu together with the long-term change of extreme precipitation during the Meiyu in this paper. The dynamic prediction skills of the Meiyu on subseasonal to seasonal time scales are further described and illustrated by using present numerical prediction models. For the multi-time scale variabilities of the East Asian Meiyu, they are closely related with the impacts of both quasi-biweekly and 30-60 day oscillation from both the tropics and the middle and high latitudes on intraseasonal time scale, the influences of El Nino-Southern Oscillation and the Tropospheric Biennial Oscillation on interannual time scale, the variations of East Asian summer monsoon on decadal time scale, and the continued impacts of global warming, Pacific Decadal Oscillation and the Atlantic Multidecadal Oscillation on interdecadal scale and long-term trend. Under the background of the global warming and the influences of urbanization and aerosol effects, the Meiyu shows some specific characteristics including significantly weakened continuous rain, uneven spatial distribution of precipitation, and increased (decreased) number of strong (weak) precipitation days. Improvements of prediction on rain belt location, total precipitation amount, persistent heavy precipitation events, and low-frequency variability oscillation during Meiyu season have been achieved with the improved dynamic models of the Beijing Climate Center since 2010.