Imaging Spectroradiometer, Standardized Vegetation and Temperature Ratio

ABSTRACT: Drought is a natural hazard characterized by below-normal precipitation, which could persist for several months or even years. This recurrent extreme climate event can cause crop damage and yield loss, which could inflict negative socioeconomic impacts all over the world. As an agricultural country, the Philippines is highly susceptible to adverse impacts of drought. Unfortunately, the country has no established method capable of characterizing agricultural drought. The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) is currently equipped with indices tailored for detecting and monitoring meteorological drought. This paper proposes a satellite-derived agricultural drought index called Standardized Vegetation and Temperature Ratio (SVTR), which can be used to detect current and historical Philippine drought occurrences. Land products acquired from the Moderate Resolution Imaging Spectroradiometer (MODIS), such as Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI), were used to devise the localized agricultural drought index. The performance of the SVTR was evaluated through the use of an existing drought metric, drought-induced crop damage reports, and other drought validation efforts. The results showed that SVTR can provide a cost-effective, near-real-time approach for detecting and assessing agricultural drought events in the country. This drought index may aid in decision-making process of crop managers, policymakers and government agencies toward drought preparedness and mitigation, as well as improved crop planning and management