The Analysis And Studv Of The Meteorological Drought Regulation Of Zhejiang Province

Drought is one of the most serious and destructive meteorological disasters, the frequency of drought is increasing with the background of global warming. In Zhejiang Province meteorological disasters are the dominating Natural Disasters,the damage of meteorological disasters are above70%and the damage caused by drought is about50%of the damage caused by meteorological disasters. The characteristics of high frequency, wide range, lasting long and big follow-up influence of drought are the reasons of its huge damage. The water resources of Zhejiang Province are comparatively rich, the annually average reaches95.5billion m3, but the per capita is only2,080about90%of the national average. Water resources are pockety in Zhejiang Province, south-west mountain regions are richer and east coast and north-east regions are comparatively poorer and rainfalls are concentrated during plum rain period and typhoon period. All of the hydrology and climate conditions decide the inevitability,universality and persistence of meteorological drought.This paper is based on the rainfall data of every March-September from1960～2009of the53hydrometeorological stations of Zhejiang Province, and used the method of Z index,regional drought index, Kriging interpolation to study and analyze the rainfall and drought regulations of Zhejiang Province. The drought regulation conclueded in this paper belongs to the regulation of meteorological drought.The main results include five aspects:1. Drought is frequent and serious in Zhejiang ProvinceDrought is very frequent and serious in Zhejiang Province, it happens every two years and half of them are great drought or above. In the past50years from1960～2009, great drought or above happened14times.2. The drought in Zhejiang Province is seasonal and on the riseFrom the60’s to the end of70’s, drought happened11times and flood happened6times in20years. But from80’s to the end of90’s, the frequency of drought and flood changed obviously,drought happened6times and flood happened11times in20years. From the beginning of21century to today,the frequency of drought increased again, flood only happened in2002,the rest of others are all drought.3. The drought in Zhejiang Province is obviously regionalThe drought in Zhejiang Province is obviously regional, the drought areal distribution is increasing from the south to north and from the east to west. The west Zhejiang Province (including Jinghua and Quzhou) which is inland hills is the main drought region,the secondary drought regions are south-east coast hills and south-west part. The comparatively less drought regions are south-east flatlands and coastal islands.4. Successional drought is very common in Zhejiang Province.Successional drought is very common in Zhejiang Province.7-year-long drought happened once from2003～2009;6-year-long drought happened once from1964～1969;2-y ear-long drought happened4times,from1971～1972,1978-1979,1985～1986and2000～2001respectively. The droughts happened from1971～1972and1978～1979are severe drought.5. Severe drought in Zhejiang Province affects wideThrough statistics we could find there are9years drought affects over50%and they are1978、2003、1964、2004、1967、1972、1971、2005、1968respectively.