An Adaptation Analysis of Drought Index in Shanxi Province of China

This paper describes the characteristics of vegetation condition index (VCI), temperature condition index (TCI), normalized differential water index (NDWI) and vegetation health index (VHI), and uses the relationship between above indices and relative soil moisture to evaluate the index adaptation. The analysis means that different indices have different adaptation. NDWI is not sensitive to the drought. VCI is sensitive to the drought only in the growing time, but has a lag of 10 days. TCI is more sensitive (the max R2=0.52) to drought and can reflect drought without lag, but not stable. However, in the growing time, VHI is the most sensitive to drought (the max R2=0.56) and stable. Finally, this paper analysis such uncertain factors as measurement condition, data quality and index calculation, which affects the adaptation of index. The result shows that VHI has a good adaptation in the growing time and has a nice prospect in drought monitoring.