Science Source

Spatiotemporal Dynamics of Global Drought

States that droughts are some of the most expensive natural disasters that society has to face, so understanding how they evolve and what are the physical mechanisms that control them is critical for improving our ability to predict them
States that past research has focused mostly on how droughts evolve in time over a fixed region and how droughts of a given duration evolve in space
Tracks how individual drought events around the world between 1979 and 2009 evolved in time and space simultaneously
Groups adjacent drought areas into clusters based on soil moisture data from the Climate Forecast System Reanalysis
Finds that while most droughts remain near their origin, the centroid of 10% of clusters traveled at least 1,400-3,100 km, depending on the continent
Finds that after droughts have grown and become intense enough, they tend to become even larger and more intense before conditions improve