An analysis of air temperature evolution and its future trend in Heilongjiang Province
GAO Yuzhong;WANG Chengwei;WANG Ji;HU Wendong;Heilongjiang Meteorological Bureau;Heilongjiang Meteorological Observatory;Beijing Climate Center;Chengdu University of Information Technology;
Using the annual mean and monthly mean air temperature data from 1961 to 2015 in Heilongjiang Province,a study was conducted on mean air temperature of the whole year,cold and warm seasons. The results showed that the interannual variation of air temperature in cold season had changed more and that in warm season had changed less. It is consistent with most other parts of China,that is,a relative colder period and a warmer period that lasted approximately 20-30 years in Heilongjiang Province under the background of unanimous warming trend in last century,while the criteria of colder and warmer periods were defined as follows: in a cycle of cold-warm,a warmer(colder) period is the continuous year that the average anomaly 0 ℃( 0 ℃). If there is a reverse anomaly in a colder or warmer period,the lasting time should be ≤2 years. It is notable that if there is a climate trend of positive(negative) anomaly ≥4 years,even anomaly is negative(positive),it must be defined as a warmer(colder) period. As for the beginning and ending years of the warmer and colder period,they must depend on the climate trend,or it is a stable turning year that anomaly 3 years. In the light of the criteria here above,the mutation years of periods was: 1964 from warmer to colder,1988 from colder to warmer,2009 from warmer to colder for cold season and the whole year. While 1969 from warmer to colder,1996 from colder to warmer and around 2015 from warmer to colder. In the periods of warmer and colder,the interannual variations are relatively small and the climate trends in colder periods are higher than those in warmer periods. There are slight differences between the beginning and ending times for warmer and colder periods,and those of warmer period lag behind of those of colder period about 6 years. Interannual variation of air temperature is more in cold season than that in warm season. It is showed that a cold season entered colder period in 2009 and a warm season entered(or turning into) colder period around 2015. By using the LMDZ4 model and periodic statistics,the warm(cold) season air temperature was projected and discussed during 2016-2030 in Heilongjiang Province. Though the results of the two methods are not completely consistent,it is shown that the phenomenon of warming may be slowed down or even stagnated,a relatively colder period more likely be found in Heilongjiang Province.
【Fund】： 国家自然科学基金项目(31671576;31671575);; 中国气象局预报员专项(CMAYBY2017-20)资助
【CateGory Index】： P423
【CateGory Index】： P423