Aims Along with intensified climatic warming and human activities,global arid areas have expanded in an unprecedented rate during the past decades.Dryland ecosystems have witnessed increased vulnerability and sensitivity to climate change.Exploring the time lag effect of climate change on dryland vegetation growth is becoming an important research highlight in current global change related studies.Methods In this study,we synthesized the normalized difference vegetation index(NDVI)from Moderate-resolution Imaging Spectroradiometer(MODIS),the monthly gridded CRU TS4.05(Climatic Research Unit Time-Series version 4.05)climate and drought information developed by the University of East Anglia,solar radiation information from ERA5(ECMWF's Fifth Generation Atmospheric Reanalysis of the Global Climate)and soil moisture information from the European Space Agency(ESA)Climate Change Initiative program(CCI).These data were designed to investigate the effects of climatic factors and their time-lag on grassland NDVI in Asian grasslands from 2001 to 2020.This analysis was conducted based on the window cross-correlation and one-dimensional linear regression.Important findings Our study revealed that:1)The grassland NDVI responded strongly to average temperature and total precipitation when there was no lag,but expressed a lag response to solar radiation and soil moisture(1-month).2)The spatial distributions of the lag response of grassland NDVI to climate change were nonuniform,with significant differences observed between the western and eastern Asian grasslands.3)We did not detect any apparent time-lag effects on interactions between grassland NDVI and self-calibrating Palmer Drought Index.4)We argue that altitude could partly modulate the response of grassland NDVI to climatic variables in the grassland of Asian drylands.
维普
万方数据