Drought is a serious climatic condition that affects nearly all climatic zones worldwide, with semi-arid regions being especially susceptible to drought conditions because of their low annual precipitation and sensitivity to climate changes. Drought indices such as the Standardized Precipitation Index (SPI) have been developed for quantifying drought conditions. Usually, calculation of drought indices requires a long record of climatic data. Remote sensing of semi-arid vegetation can provide vegetation indices which can be used to link drought conditions when correlated with various drought...