Abstract:

Based on the daily maximum temperature data covering the period 1961–2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days (HTDs) and the mean daily maximum temperature (MDMT) during annual and monthly HTDs in East China were studied. The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃ in the past 45 years. Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time, oscillating with a cycle of about 12–15 years. The mean annual HTDs were more in the southern part, but less in the northern part of East China. The MDMT during annual HTDs was higher in Zhejiang, Anhui and Jiangxi provinces in the central and western parts of East China. The high temperature process (HTP) was more in the southwestern part, but less in northeastern part of East China. Both the HTDs and the numbers of HTP were at most in July, and the MDMT during monthly HTDs was also the highest in July. In the first 5 years of the 21st century, the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations, both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October, the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest.

Key words: climatic characteristics, high temperature days (HTDs), mean daily maximum temperature (MDMT) during HTDs, high temperature process (HTP), East China