Extreme Drought in Tropical South America

Research from Amir Erfanian, Dr. Guiling Wang, and Lori Fomenko at the University of Connecticut recently discussed the severity of the 2016 drought over tropical South America. One of three 100-year events in the past decade, the most recent drought was also the most severe and led to widespread shortages in water storage and vegetation damage throughout the region. Their work, “Unprecedented drought over tropical South America in 2016: significantly under-predicted by tropical SST” was published in Scientific Reports.

In addition to an estimated 6-8 billion USD in annual economic losses, droughts have wide ranging social and environmental impacts. Drought-prone tropical South America has recently experienced multiple record-breaking droughts in just over a decade (2005-2016). Extreme droughts in 2005 and 2010 caused record-breaking numbers of annual wildfires and overall carbon emissions. In 2012, an even more severe drought caused widespread water and power shortages.

But, the 2016 drought broke all previous records in its intensity and severity. This was in part caused by a large El Nino causing warmer than usual tropical oceans. Greenhouse warming and deforestation were also suspected of contributing to the excessive severity. Severe shortages in Terrestrial Water Storage (TWS) i.e. water on the surface of the Earth was detected, as well as vegetative decline over the region.

The observed trends may be warning signs of high susceptibility to recurrent extreme droughts in the future throughout the region.