Abstract: The cotton production area in Hebei Province is located in the north boundary of the cotton growing area.It has a large span from the south to the north,and the climate diversity here is so prominent that the cotton yield is sensitive to the climate conditions.Based on the data of the sunshine duration,temperature,precipitation and cotton yields from 1965 to 2005 in Hebei Province,the key climate factors affected cotton yields in the different cotton production areas were identified by the integral regression method.According to the impact coefficients of the precipitation,temperature and sunshine duration on the cotton yield,the cotton production area in Hebei Province was divided into three precipitation impact regions,three temperature impact regions and three sunshine duration impact regions.The inter-annual impact variations of the precipitation,temperature and sunshine duration on the cotton yield in the different cotton production areas were analyzed by the integral regression method.

Key words: Coefficient of climate impact, Coefficient of climate impact, Cotton yield, Hebei Province