Global desert variation under climatic impact during 1982-2020

作     者：Yao CHEN Huayu LU Huijuan WU Jingjing WANG Nana LYU Yao CHEN;Huayu LU;Huijuan WU;Jingjing WANG;Nana LYU

作者机构：School of Geography and Ocean ScienceFrontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing210023China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2023年第66卷第5期

页      面：1062-1071页

核心收录：

学科分类：07[理学] 0809[工学-电子科学与技术（可授工学、理学学位）] 09[农学] 0903[农学-农业资源与环境] 0705[理学-地理学] 0706[理学-大气科学] 0833[工学-城乡规划学] 0713[理学-生态学] 

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42021001 41920104005)。 

主　　题：Global desert Dryland Spatial variations Climate factors CMIP6 

摘      要：Deserts are important landscapes on the earth and their variations have impacts on global climate through feedback processes.However,there is a limited understanding of the climatic controls on the spatial and temporal variations of global deserts.Here,we use climate reanalysis datasets,global land use/land cover(LULC)products and the CMIP6(Coupled Model Intercomparison Project)model outputs to calculate the changing of global deserts during 1982-2020,and estimate future spatial trends of global deserts.Our results show that mean annual global desert area over this period is 17.64×10^(6)km^(2),accounting for 12%of the terrestrial land.Desert areas decreased rapidly from the end of the 1980s to the 1990s in North Africa and Australia,followed by a slow expansion in early 21st century globally.Spatio-temporal variations of areas of arid climate are characterized by interdecadal fluctuations,and there are clear regional differences in dynamic s of the aridity index(AI,used here as a proxy for the area of drylands)and desert areas.Statistical analyses reveal that increased vegetation cover is directly related to the reduction of desert area,while potential evaporation,surface temperature and humidity are also significantly correlated with the desert area.The relationship between wind speed and desert dynamics varies regionally.The results of the CMIP6simulations suggest that global deserts will expand in the 21st century,albeit at different rates under the ssp245 and ssp585scenarios.Desert expansions are modelled to be greatest in Asia,Africa and Australia,while those of southern North Africa may reduce as their southern borders migrate northwards.