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Abstract

The atmospheric aridity is represented by the Vapor Pressure Deficit (VPD). The decadal abrupt change of VPD from 1980 to 2020 was analyzed by the moving t-test technique, and the distribution and change characteristics of abrupt VPD change in time and space were studied by statistical analysis and other methods, and the possible causes were explored by correlation analysis. Our results show that there are marked regional differences in the number, duration, and start year of the persistent decadal abrupt change. A significant decadal abrupt change toward increased in VPD was observed in 60.54% of land regions, with some regions more pronounced in Eurasia, Africa, and South America, whereas central North America and western Siberia did not show significant changes. The greater number and longer duration of abrupt change toward increased that began in 1993-2000 suggest that the areas where a significant increase in VPD occurred on land were larger during the 1990s. And another large-scale persistent abrupt change toward increased occurred in 2009, and global atmospheric aridity was further exacerbated in nearly 10 years. For the longest duration persistent abrupt change, the correlation between VPD and actual water vapor pressure was strengthened significantly in southern Central Asia, Europe, and most parts of China, and the enhancement of the effect of water restriction may be an important factor for the continuous and significant increase of VPD.