“…Satellite-derived Normalized Difference Vegetation Index (NDVI) data have long been used to monitor the impacts of drought on vegetation greenness, which is sensitive to soil moisture conditions and precipitation (Gu et al, 2007(Gu et al, , 2008Karnieli et al, 2010;Kogan, 1995;Pettorelli et al, 2005;Reed et al, 1994;Williams et al, 2013). However, the vegetation responses to drought represented by NDVI may vary with vegetation types (e.g., Fensholt et al, 2012;Gamon et al, 1995;Okin et al, 2018;Reed et al, 1994;Vicente-Serrano et al, 2013). Geographically differentiated average climate can also exert influence on the vegetation responses to drought.…”