AsalientfeatureoftheEastAsianorographyisthehugeTibetanPlateauinthewestandthebroadPacificintheeast.ReversalsinthetemperaturegradientbetweentheEurasiancontinentandtheadjacentPacificOceanassociatedwiththeprogressionoftheseasonshaveproducedtheprominentEastAsianmonsoonsystem.Thesummermonsooncontributesabout49%oftheannualprecipitationoverEastAsia.Anomalousmonsoonactivitieshaveandwillcontinuetoaffectmorethanonebillionpeoplelivinginthisarea(ZhouTJetal.,2009,2011).