Unless my eyes deceive me, it looks like there is no net change in global drought area for 30 years.
The graph shows the proportion of the planet in drought, by intensity, 1982-2012. The graph comes from a paper in a new Nature publication called Scientific Data and is open access.
Color scheme: D0 (yellow) = abnormally dry; D1 (orange) = moderate drought, D4 (red) is extreme drought.
h/t to Marc Morano and source: http://rogerpielkejr.blogspot.com/2014/05/fraction-of-globe-in-drought-1982-2012.html
The open access drought graph paper: http://www.nature.com/articles/sdata20141
Global integrated drought monitoring and prediction system
- Scientific Data (2014) doi:10.1038/sdata.2014.1
Drought is by far the most costly natural disaster that can lead to widespread impacts, including water and food crises. Here we present data sets available from the Global integrated drought monitoring and prediction system (GIDMaPS), which provides drought information based on multiple drought indicators. The system provides meteorological and agricultural drought information based on multiple satellite-, and model-based precipitation and soil moisture data sets. GIDMaPS includes a near real-time monitoring component and a seasonal probabilistic prediction module. The data sets include historical drought severity data from the monitoring component, and probabilistic seasonal forecasts from the prediction module. The probabilistic forecasts provide essential information for early warning, taking preventive measures, and planning mitigation strategies. GIDMaPS data sets are a significant extension to current capabilities and data sets for global drought assessment and early warning. The presented data sets would be instrumental in reducing drought impacts especially in developing countries. Our results indicate that GIDMaPS data sets reliably captured several major droughts from across the globe.