关键词: 华北平原, 积温, 降水, 变化特征

Abstract: The temporal and spatial tendency,differences of agricultural climate resources in the North China Plain was analyzed by using linear-trend estimate,based on the daily air temperature and precipitation of 53 meteorological stations from 1961 to 2005 in the North China Plain.The result indicated that the inter-annual change between the annual accumulated temperature≥0℃,the accumulated temperature≥10℃ from May to October,the absolute value of annual accumulated temperature<0℃ and the air temperature existed a corresponding relationship in the whole North China Plain.There was a poor period of heat before the middle of 1970s,the heat was increasing from the 1970s to the end of 1990s,and it was quite abundant in the last 15 years.The heat increased greatly in the north of the North China Plain and on the east coast of Shandong.But the accumulated temperature higher than 10℃ during the crop growing season decreased in the central south of the North China Plain.The annual precipitation and precipitation in summer decreased faintly,and the fluctuation of precipitation inter-annual was intensified.Differently,the annual precipitation was increased in the last three years(2003-2005).The results also showed that the precipitation differences between the south part(coastal area) and the north part(inland) was getting smaller,especially in summer.

Key words: North China Plain, North China Plain, Accumulate temperature, Precipitation, Changing characteristics