Drought monitoring based on HJ-1A/1B CCD data

HJ-1A/1B is the first small satellite constellation in China for environment and disaster monitoring and forecasting. This paper is aimed to discuss the potential application of HJ-1A/1B CCD data in drought monitoring in southwestern Karst area in China. The Anshun area in Guizhou province which suffered greatly from drought disaster in 2010 was selected as study area. The Normalized Difference Vegetation Index (NDVI), Perpendicular Drought Index (PDI) and Modified Perpendicular Drought Index (MPDI) were used in a time-series analysis based on multi-temporal HJ-1A/1B data to monitor the crop growth and drought status. The characteristic, suitability and influence factors of each model were also discussed. The results showed that PDI, MPDI performed well by utilizing HJ-1A/1B data in drought monitoring, in which MPDI presented a better performance than PDI, especially in densely vegetated area. Precipitation is a major influencing factor in drought monitoring, and it has more impact on MPDI than PDI. The combination of drought monitoring index and vegetation index (NDVI) in a time-series analysis could give a better description of crop growth and drought condition. This work is hoped to facilitate application of HJ-1A/1B data in crop and drought monitoring in western Karst area of China and contribute to the decision-making of Chinese government when confronting drought disasters.