Characteristics of Winter Low Temperature Years and Its Impact Factors in Liaoning Province

In order to analyze the variation characteristics of winter low temperature years in Liaoning Province,the impact factors of winter low temperature years in Liaoning Province was systematically studied,so as to provide valuable reference for the climatic prediction.Based on the monthly mean temperature data of 53 observational stations in Liaoning Province during 1961 to 2013,this study was carried out.Results showed that winter low temperature years in Liaoning Province had three phases :Low temperature years in Liaoning continuous appeared during 1961 to 1986.During 1987to1998 there was no low temperature event appeared.Low temperature event and high temperature event appeared alternately during 1999 to 2013.During 1961 to 2013,there were 22 times of low temperature event appeared.The characteristic of extreme low temperature years showed continuous 2to 3 years or more.The study of impact factors demonstrate that,AO,meridional circulation,East Asian winter monsoon and La nina are the impact factors of low temperature years in Liaoning Province.The leading impact factors are La nina and the negative phase of AO,and the strong phase of East Asian winter monsoon was the key impact factor.