Abstract: he model for estimating grain yield was established, through analyzing the relationship between climatic grain loss and disaster exposure by using multiple regression method based on the statistical data of agro meteorological disaster exposure and grain yield in Northeast China from 1981 to 2010. Meanwhile, the impact of drought, flood, low temperature and wind-hail on grain loss was evaluated by using grey relational analysis on the slight, moderate and severe damage level respectively. The results showed that there was significant correlation between climatic grain loss and statistical data of agrometeorological disaster exposure (P＜0.01). The coefficients of determination (R2) of regression models were 0.76 (Heilongjiang province), 0.78 (Jilin province) and 0.87 (Liaoning province), and their average relative errors between simulated yield and real yield were -0.06%, -0.32% and -0.20% respectively. The results indicated that statistical data of agrometeorological disaster exposure was a good indicator for predicting regional grain loss and grain yield while the meteorological disaster occurred. They were dependable basis for estimating of regional grain yield and evaluating of agrometeorological disasters. The results of grey relational analysis showed that the correlation degrees between drought and grain loss were the maximum in three provinces on the slight damage level, the correlation degrees between windhail and grain loss were the maximum in three provinces on the moderate and severe damage level, the correlation degrees between low temperature and grain loss were not the maximum. Therefore, the main meteorological disaster was light degree and wide range of drought or strong and local based wind hail. However, as one of the most obvious warming regions, low temperature was no longer the most important disaster in Northeast China.

Key words: Agrometeorological disasters, Climatic grain loss, Yield loss caused by disasters, Estimation model