1980-2022年全球陆地高温干旱时空特征变化分析OA

Compound high-temperature and drought events intensify water scarcity,threaten global food security,disrupt ecological stability,and markedly elevate wildfire risks.This study leverages global temperature and precipitation data from 1980 to 2022,employing advanced statistical methods and a Copula model to systematically evaluate the spatiotemporal dynamics of compound high-temperature and drought events across terrestrial regions,defined through a concurrent framework using the Standardized Temperature Index(STI)and Standardized Precipitation Index(SPI).Results show that:(1)western South America experiences prolonged compound events,averaging approximately three months,with severity patterns closely aligned with duration distributions.High-temperature intensity ranges from 1.2 to 1.5,predominantly in Asia,Europe,southern South America,North America,northern Africa,and Australia,while drought intensity peaks in Greenland and central Brazil.(2)STI and SPI exhibit a robust positive correlation year-round.In Asia,compound events concentrate in the southwest from January to May,extend westward in June,migrate eastward in August-September,and diminish from October to December.(3)The frequency of compound events shows a significant upward trend,with high-threshold events increasing markedly after 2000.From 2000 to 2022,relative to 1980-1999,the Event Change Proportion(Eprop)increased,with high-temperatureas the primary driver.(4)Under mild and moderate heat conditions,the probability of compound high-temperature and drought events increases with a higher drought threshold;however,under severe heat conditions,the probability decreases with a higher drought threshold.High-probability regions are concentrated in northern Eurasia,Africa,northern North America,and western South America.