Variations Of Winter Temperature In DaLian And Analysis On Its Impact Factors

Based on the analysis of the winter temperature characteristics in DaLian. The corresponding atmospheric circulation patterns in cold and warm winter years of Dalian are particularly discussed in this paper. The possible relations between the winter temperature anomalies in DaLian and the preceding sea surface temperature in the Indian Ocean are also studied. The result are outlined as following: 1) The warming trend is obvious in four seasons, and the warming rates in spring and winter are higher than those in other seasons. 2) The winter temperature in DaLian showed decreasing trend in 1960's, but it began to rise in the middle of 1970's, and other regions of the warming trend in 1990's is very obvious.3)The air temperature anomaly existed 3-4-year, about 8-year and 16-17-year periodic variation in winter in DaLian.4) The variations of winter temperature in DaLian were similar with those in china.5) There are significant difference in their SLPA fields, height anomaly fields at 500hPa and zonal winds anomaly fields at 300hPa in cold and warm winter years of Dalian. Moreover, it is found that Mongolia High, East Asian Trough, Polar Front Jet and the location, area and intensity of Polar Vortices are notable different, which interpret Polar Front Jet, East Asian Trough and Mongolia High have an important impact on winter temperature abnormity of Dalian. 6) The winter temperature abnormity of Dalian has obviously positive correlation with the preceding sea surface temperature in the Indian Ocean. It is found that waters bounded by 5°S~5°N, 60 ~ 75°E are the key zones of SST anomalies that affect the winter temperature in these regions over April-July . Long-term air-sea interactions make it possible for preceding SST anomalies to affect the general circulation that come afterwards , causing wintertemperature anomalies in DaLian.