Assessing drought probability for agricultural areas in Africa with coarse resolution remote sensing imagery

作者：Rojas O; Vrieling A; Rembold F^*

来源：Remote Sensing of Environment, 2011, 115(2): 343-352.

DOI：10.1016/j.rse.2010.09.006

• Agricultural drought
• Remote sensing
• NDVI
• Africa
• Drought probability

Drought is one of the most frequent climate-related disasters occurring across large portions of the African continent, often with devastating consequences for the food security of agricultural households. This study proposes a novel method for calculating the empirical probability of having a significant proportion of the total agricultural area affected by drought at sub-national level. First, we used the per-pixel Vegetation Health Index (VHI) from the Advanced Very High Resolution Radiometer (AVHRR) averaged over the crop season as main drought indicator. A phenological model based on NDVI was employed for defining the start of season (SOS) and end of the grain filling stage (GFS) dates. Second, the per-pixel average VHI was aggregated for agricultural areas at sub-national level in order to obtain a drought intensity indicator. Seasonal VHI averaging according to the phenological model proved to be a valid drought indicator for the African continent, and is highly correlated with the drought events recorded during the period (1981-2009). The final results express the empirical probability of drought occurrence over both the temporal and the spatial domain, representing a promising tool for future drought monitoring.

• 出版日期2011-2-15