Temporal And Spatial Analysis Of Winter Air Temperatures In Hulun Buir Region

Hulun Buir City, located at China’s northeast, the location is high, vulnerable to the impact of the polar vortex throughout the year. The weather is cold, interannual temperature change greatly, the cold wave is the geographical features of meteorological disasters in winter. So,the research on regulations of winter air temperature changes is not only have important practical significance to disaster prevention and reduction in Hulun Buir region and a certain role in indicating the occurrence of cold wave weather in the North-east China In this paper, we use Hulun Buir region1971-2009winter air temperatures、NOAA global monthly average gridded SST data and NCEP/NCAR reanalysis monthly mean sea-level pressure、height and wind fields data, analyze the temporal and spatial variation characteristics of the local winter air temperatures, and on this basis, analyze the current and previous factors which influnce the abnormal winter air temperatures in this region. The main results may be concluded as follows:(1)To1986for the sector, the local winter air temperatures from colder period into warmer, fluctuations in winter air temperatures increased in the90years,2000is the warmest year during this period.(2)The warming trend was obvious in the rescent39yaers and reached a rate of0.6℃/10-year, higher than the national average warming amplitude.(3)The air temperature anomaly existed3-4-yaer,7-8-yaer and12-14-yaer periodic variation in winter.(4)Winter air temperatures change with synchronous, also exist differences in the degree of change; bounded by the Greater Xing’an Mountains, the warming is obvious in ridge southeast compared with ridge northwest.(5)When Siberian High strengthen East Asian trough deepened、the strong side of the polar front jet、Asian polar vortex southward、the trough in East Asia eastern deepened and the South Asia high is weaker, Hulun Buir area is prone to cold winter, otherwise prone to warm winter.(6)The western equatorial Pacific Ocean (160°E-160°W,5°S-5°N) is the critical region to Hulun Buir winter air temperatures, March to May of that year is the critical period as the impact on Hulun Buir winter air temperature.