Using Normalized Difference Vegetation Index for Drought Monitoring in the Loess Plateau of China

摘要

This study used AVHRR GIMMS NDVI data to monitor drought in the Loess Plateau of China having arid and semi-arid climate. The AVHRR (Advanced Very High Resolution Radiometer) GIMMS (Global Inventory Monitoring and Modeling Studies) NDVI (Normalized Difference Vegetation Index) (2000-2006) and precipitation datasets covered a seven-year time period with three consecutive months in the growing season, which were used to calculate the Pearson correlation coefficients between NDVI and precipitation for all stations. Different time lag schemes were attempted and the highest correlation coefficients (Pearson correlation coefficients) were gained while correlating NDVI to three-month (current plus last two months) precipitation. The NDVI deviation were used to detect the drought and the result showed that AVHRR GIMMS NDVI could report precipitation undulations in the study area, which can be used to monitor drought for early drought alertness.