Study on climatic characteristics and assessment methods of high temperature weather in Jilin province

Using the daily maximum temperature data of 50 stations in Jilin province from 1951 to 2018, the temporal and spatial distribution characteristics of high temperature weather in Jilin province were analyzed by means of climate tendency rate, anomaly accumulation, gray correlation degree and normal distribution.The comprehensive index of high temperature process, index of high temperature process evaluation and index of climate recurrence period were established.The results show that in recent 68 years, the annual average number of high temperature days in Jilin province has an increasing trend, with 0.04 d per decade.The number of high temperature in Jilin province demonstrates its change feature in different period of time.Less number of the high temperatures occurred during 1959 to 1996 whereas more number of the high temperatures happened during 1951-1958 and 1997-2018.The high temperature weather in Jilin province mainly occurs in mid-June to mid-august, with the most in late July and more in early August.The western part of Jilin province is a high-temperature area.The average number of high-temperature days decreases from west to east of Jilin province.This paper classifies the high temperature process and gives an evaluation index of grade and climate recurrence period.For the high temperature process, the comprehensive index evaluation index and each sub-item evaluation index can be used to evaluate.It is convenient to apply in decision-making operation.