历史时期中国东部年代际干旱模拟的研究进展

RESEARCH PROGRESSES OF DECADAL MEGADROUGHT MODELING IN EASTERN CHINA DURING HISTORICAL PERIOD

本文总结了历史时期中国东部年代际干旱时空特征及成因机制的最新研究进展。作为典型季风区,中国东部年代际干旱均与典型的弱季风事件相关,空间特征上呈现出南涝北旱或者全区干旱的模态。成因机制方面,年代际干旱由气候系统内部变率(PDO、AMO)和外强迫(包括火山活动、太阳辐射、温室气体、人为气溶胶、土地利用等)共同作用引发,其中,气候系统内部变率主要对年代际干旱起到触发作用,外强迫对干旱强度和持续时间起到加剧作用;此外,外强迫还通过改变气候系统内部变率的频次和强度来改变年代际干旱的频次、强度、持续时间;最后,本文还探讨了历史时期中国东部年代尺度干旱研究中未解决的问题及未来研究方向。

This paper summarizes the recent research progresses on the spatio⁃temporal characteristics and mechanisms of decadal megadroughts in Eastern China during historical period.As a typical monsoon region,the decadal megadroughts in Eastern China(25°~40°N,105°~120°E)are associated with typical weak monsoon events,and the spatial characteristics resemble the patterns of southern flood and northern drought or drought over the whole region.In terms of the mechanism,decadal megadroughts are caused by the combined influences from internal variability of the climate system(PDO,AMO)and external forcings(including volcanic activity,solar radiation,greenhouse gases,anthropogenic aerosols,land use and land cover,etc.).The decadal megadroughts are mainly triggered by internal variability of the climate system,and intensified by the external forcings on intensity and duration.In addition,external forcings dominate the frequency,intensity,and duration of decadal megadroughts through modulating the frequency and intensity of internal variability of the climate system.Finally,the unsolved problems and future research directions of decadal megadrought in Eastern China during historical periods are also discussed.