Research on the Temporal and Spatial Changes of Global Meteorological Drought Since the 20th Century
[Purposes]Meteorological drought firstly occurs of the four types of drought,and exploring the characteristics and laws of meteorological drought is of great significance for early warning,disaster pre-vention and mitigation of other types of drought.[Methods]Based on the medium and long series of me-teorological data of CRU TS dataset,this paper uses standardized rainfall evapotranspiration index(SPEI)to characterize meteorological drought situation,uses Mann-Kendall trend test and least squares regression analysis to study the global meteorological drought changes from 1901 to 2021,analyzes their spatiotemporal variation characteristics,and introduces wetness index(HI)to explore the influence of dry and wet conditions on drought duration.[Findings]Since the 20th century,the global meteorological drought has shown an overall aggravation trend,especially after 2001.The average drought duration of most river basins in the world is between 13～16 months,and the duration of drought in most river basins has not changed significantly.[Conclusions]The duration of drought at the basin scale is closely related to regional dry and wet conditions.The greater the accumulated humidity,the longer the drought lasts.
NETL
NSTL
万方数据
