Analyses on the Heat Wave Events in Shanghai in Recent 138 Years
Better understanding on the characteristics of heat wave evolution and occurrence is very im portant for prevention of its associated disasters.Based on three criterions of the heat wave events, defined according to the threshold of high temperature and warning signal of China Meteorology Administration,the effective accumulated high temperature (EAHT), the maximum temperature of Xujiahui of Shanghai,China during 1873-2010, the multi-scale time-frequency characteristics of the heat wave events in Shang hai is examined.Moreover, the NCEP reanalysis data and the circulation indices of NCC are further em ployed for analysis of the average atmospheric circulation anomaly.The major results are: (1) The EAHT and occurrence frequency of heat waves can be jointly used for reasonable representation of heat wave-in duced hot weather.(2) There are totally 214 heat wave events in Shanghai in the recent 138 years with the average EAHT of 8.3 ℃, and July is more warm than August.(3) There are three major periods when the occurrence frequency and intensity of the heat wave events and EAHT are evidently more than normal,i.e., early 1890s to the end of the century, late 1920s to early 1950s, since the early 1980s especially in the 21st century.The most intensive heat wave occurred in the year of 1934; the frequency of heat wave-in duced hot weather increases significantly during the last 10 years.(4) The large scale circulation related to the abnormal partial strong heat wave are mainly featured by the abnormal intensive summer subtropical high over the north hemisphere, the west-drifted west Pacific subtropical high (e.g., 122°E), and the much weakened India-Burma trough compared to the average 1951-2010 years.
Heat waveEffective accumulated high temperatureMulti-scale time-frequency charac teristicsAtmospheric circulation anomaly
NETL
NSTL
万方数据
维普
