The Variation and Relation of 500 hPa Height Field in China-Mongolia and Surface Temperature of North China in Winter in Recent 50 Years

By analyzing the variations of 500 hPa height field and monthly mean surface air temperature of 160 stations in China, the reasons that winter surface air temperature appearing interdecadal change in North China are discussed. The results are as following: a) It is shown that the temperature in North China had positive trend and interdecadal change in winter. b) The positive trend of height of China and Mongolia was corresponding to the strong zonal circulation, weak meridional circulation and weak cold air activities; c) It is shown that the winter temperature in North China during the period of the past 51 years were closely related to the positive trend of 500 hPa height field in China and Mongolia.