Drought Assessment Of Henan Province Based On Meteorological And Hydrological Data

Drought is one of the most serious natural disasters which is the occurrence frequency,scope of influence and the most harm,and it seriously affects people's life and social stability.Henan Province is a major agricultural province in China,particularly the influence of the drought on it is serious.Therefore,monitoring and assessment of drought situation in Henan Province,is of profound significance to the development of Henan Province.This paper evaluates the drought in Henan Province through two aspects: meteorological drought and hydrological drought,while meteorological drought selecting percentage of precipitation anomalies and standardized precipitation index establishes models,and hydrological drought selecting runoff Z index and standard runoff index establishes models,to evaluate the drought in Henan Province,to evaluate the drought in Henan Province,and to analysis the applicability of various models combining with the drought history of Henan Province.The main research results are as follows:1.Using Henan Province nearly 52 years of meteorological data in 1961-2012 to evaluate drought situation of Henan Province,the results show that:(1)based on percentage of precipitation anomalies: drought events has little correlation with the change of time and the regularity is not strong;drought event trends show:(1)increase gradually from south to north,(2)increased gradually from the western mountains to the east plain;the frequency distribution of annual drought occurred in 31.25%~45.03%.(2)based on the standardized precipitation index: the short time scales of SPI is obvious to reflect the degree of monthly precipitation change;the long time scales of SPI is slow to reflect the degree of monthly precipitation change.2.Using Henan Province nearly 45 years of hydrological data in 1956-2000 to evaluate drought situation of Henan Province,the results show that:(1)based on runoff Z index: drought events has little correlation with the change of time and the regularity is not strong;drought event trends show:(1)light drought increases gradually from north to south,(2)excessive drought gradually decreases from north to south;frequency distribution of annual drought occurred in 31.67% ~ 31.67%.(2)based on standardized runoff index: the short time scales of SRI is obvious to reflect the degree of monthly runoff change;the long time scales of SRI is slow to reflect the degree of monthly runoff changes.3.Through the drought conditions comparation of four kinds of drought indexes in Henan Province,the results showed that: the drought years of drought index evaluation results are in general agreement with the actual drought years;meteorological drought assessment accuracy is slightly higher than that of hydrologic drought,and standardized precipitation index is better than percentage of precipitation anomalies;the drought frequency of runoff Z index always significantly higher than that of the other three drought index;on the frequency of heavy drought and excessive drought,percentage of precipitation anomalies is higher than the other three drought index.