Comparison between remote-sensing-based drought indices in Tehran

Drought is natural hazard which has causing several impacts, such as decreasing of air and water quality, land degradation, forest fire, decreasing of agricultural crops production. Drought assessment using drought indices have widely conducted for drought monitoring. Remote-sensing-based indices defined as an index which using remote sensing data for mapping the drought condition in particular area or region. This research aims to compare remote-sensing-based drought indices, namely TCI, VCI and VHI to obtain a better understanding about the differentiation between each index, and their application for monitoring drought in Tehran from 1982 to 2017. LST and EVI data were used to construct the indices. The result showed, each index proved to be useful, quick, sufficient and inexpensive tool for drought monitoring. However, each index has its differences. TCI proved to be detected drought sensitively in dry season or months when high temperature occurred. Meanwhile, VHI which the enhancement of TCI and VCI has combined two indicators to provide better comprehension about drought occurrence.

کلیدواژه ها:

Drought indices ، Remote sensing ، VCI ، TCI ، VHI ، Tehran