Solar radiation contributed to the 2005 and 2010 Amazon droughts

Climate change has a great influence on vegetation growth and vegetation responds to Climate change with a certain time lag[1]. Considering the time-lag effects, this study applied MODIS-NDVI (Normalized Difference Vegetation Index) and CRU (Climate Research Unit) solar radiation data to analyze the vegetation responses to solar radiation in Amazon region. Based on the response mechanism, the variation of vegetation and solar radiation during the 2005 and 2010 Amazon droughts were investigated to identify the impact of the solar radiation change on Amazon vegetation growth. Result suggests that the response of Amazon forests vegetation to solar radiation vary with different local hydrothermal conditions. In the intensely affected areas of 2005 and 2010 Amazon droughts, a significant increase in pre-drought solar radiation was found, which means solar radiation has a significant contribution to the two extreme droughts.

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