According to research released on Thursday, climate change is to blame for the drought that has left 4.35 million people in the Horn of Africa in need of humanitarian assistance, with 43,000 reported to have died in Somalia last year.
Aid agencies have dubbed the drought in Ethiopia, Kenya, and Somalia “the worst in 40 years,” owing to the failure of five consecutive rainy seasons from October 2020. The World Weather Attribution (WWA) consortium of worldwide climate scientists estimated that rising greenhouse gas emissions increased the chance of drought by a factor of at least 100.
“Climate change has made this drought exceptional,” said Joyce Kimutai, a climate scientist with the Kenya Meteorological Department who worked with WWA to identify the impact of climate change. Researchers headed by her came to the conclusion that minimal rainfall and evapotranspiration “would not have resulted in drought at all” on a planet 1.2 degrees Celsius colder than ours.
Global droughts are more difficult for scientists to attribute to climate change than high temperatures and heavy precipitation.
The WWA team discovered that, as a result of climate change, the long rains (March to May) in the Horn of Africa are now twice as likely to fall short, but the short rains (October to December) are now wetter.
However, La Nina, an ocean phenomenon characterized by unusually cold water in the equatorial Pacific, is also responsible for East Africa’s below-average short rainfall during the previous three years. This helped to reduce the impacts of rising humidity caused by climate change.
“If you have a doubling of the chance of a severe drought, that really sets the stage for these sequential shocks that have devastated the region,” climatologist Chris Funk of the University of California, Santa Barbara, who was not involved in the study, said.
As a consequence of the warmer climate, more water is lost to evaporation and transpiration by plants and soil in the Horn of Africa.
“This drought is primarily due to the strong increase in evaporative demand caused by high temperatures,” Kimutai remarked.
She claimed the region is finally receiving some rain, defying predictions of a sixth straight failed rainy season.
Farmers and pastoralists need much more rain before they can begin to recover, but “it’s really positive that we’re seeing rainfall in the region at the moment,” Kimutai said.
