Characteristics analysis and trend forecast of drought and flood in Northeast China

Based on the data of drought and flood disasters in Northeast China during 1751 to 2000,the characteristics of drought and flood disasters are analyzed.The relationship between the meteorological factors and the drought and flood disasters has been established,and three methods for forecasting the trends of floods and droughts,which are the transition probability,the phase of the sun activities and El Nino,are proposed.The future trends of drought and flood disasters for the period of 2001 to 2010 are forecasted.The results are summarized as follows: The drought and flood disasters in the 20th century are more serious than before,especially the times of the drought disasters have increased obviously than those in the 19th century.There will be more than 2 drought disasters and 1-2 flood disasters in Northeast China for the period of 2001-2010 and the critical period of flood disasters will be in about 2007.It has been proven to be an effective reference for guiding the practical flood hazard control and mitigation in Northeast China.