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The World Drought Picture: 1951-2010

Paper Reviewed
Spinoni, J., Naumann, G., Carrao, H., Barbosa, P. and Vogt, J. 2014. World drought frequency, duration, and severity for 1951-2010. International Journal of Climatology 34: 2792-2804.

Spinoni et al. (2014) write that drought "is a natural hazard related to a prolonged lack of rainfall that leads to a temporary decrease or deficit in natural water availability," citing Vogt and Somma (2000), while noting that it should not be confused with aridity, "which is a permanent climatic feature of a certain region," citing Wilhite (1993), or with water scarcity, which is "a situation where the available water resources are insufficient to satisfy long-term average requirements." With this understanding in mind, working with precipitation data they obtained from the global gridded data set of the Global Precipitation Climatology Centre of the Deutscher Wetterdienst (Becker et al., 2013), Spinoni et al. developed maps of global drought frequency, duration, and severity for the periods 1951-1970, 1971-1990 and 1991-2010.

In discussing their findings, the five Italian researchers report that on a continental basis, the Americas and Russia experienced "a significant decrease in drought variables," while the Mediterranean, Central Africa, Amazonia, North-Eastern China and Southern Australia are subject to significant increases." Also, they state that "a linear trend analysis between 1951 and 2010 shows a small global increase in each drought component," although, paradoxically, they say that "the 1950s proved to be the decade most hit by severe and prolonged drought events."

All things considered, it would appear there has been no dramatic increase in global drought over the past six decades.

Becker, A., Finger, P., Meyer-Christoffer, A., Rudolf, B., Schamm, K., Schneider, U. and Ziese, M. 2013. A description of the global land-surface precipitation data products of the Global Precipitation Climatology Centre with sample applications including centennial (trend) analysis from 1901-present. Earth System Science Data 5: 71-99.

Vogt, J.V. and Somma, F. (Eds.). 2000. Drought and Drought Mitigation in Europe. Kluwer Academic Publishers, Dordrecht, The Netherlands.

Wilhite, D.A. 1993. Drought Assessment, Management and Planning: Theory and Case Studies. Kluwer Academic Publishers. Boston, Massachusetts, USA.

Posted 1 October 2014