WWA Study: Global Warming Enabled Horn of Africa Drought.

A new analysis released by World Weather Attribution (WWA) has suggested that the devastating drought affecting the Horn of Africa, which has left millions in need of humanitarian aid, would not have been possible without climate change.

The region has experienced five consecutive failed rainy seasons since October 2020, with aid groups labeling it the "worst drought in 40 years". The study by WWA has found that rising greenhouse gas emissions made the drought at least 100 times more likely, demonstrating the impact that human activity is having on the planet's climate systems.

The drivers behind the drought are complex, with many factors contributing to the crisis. However, WWA's analysis has shown that climate change has played a significant role.

In a 1.2 degrees Celsius (2.2 degrees Fahrenheit) cooler world, the combination of low rainfall and evapotranspiration “would not have led to drought at all”, according to the report. This highlights the crucial role that global efforts to reduce emissions and limit temperature rise can have in preventing further devastation.

Unlike with extreme heatwaves and heavy rainfall, scientists have a harder time pinning down climate change's contribution to droughts around the world.

However, using computer models and climate observations, the WWA team determined climate change had made the Horn of Africa's long rains from March through May twice as likely to underdeliver, and the short rains from October through December wetter.

This demonstrates the complexity of climate systems and the various ways in which they can be impacted by rising temperatures.

The nearly three-year drought has also coincided with La Nina, an ocean phenomenon resulting from unusually cold water in the equatorial Pacific, known to cause below-average short rains in East Africa. This ultimately counteracted the excess moisture added by climate change.

However, if there had not been an ocean phenomenon like La Nina, the impact of the drought would have been even more severe.

The Horn of Africa region is already dealing with multiple crises, including conflict and displacement, and the drought has only added to the suffering. Many people affected across the region are pastoralists or farmers who have watched crops wither and water sources run dry.

In addition to less rainfall in the Horn of Africa, a warming climate means more water is evaporating from the soil and transpiring from plants into the atmosphere.

“This drought is primarily due to the strong increase in evaporative demand caused by high temperatures,” said Joyce Kimutai, a climate scientist with the Kenya Meteorological Department who worked with WWA to tease out climate change’s role.

Despite initial predictions of a sixth failed rainy season, the region is now receiving some rain, although much more is needed to help farmers and pastoralists recover. "It's really positive that we're seeing rainfall in the region at the moment," said Kimutai.

The WWA study highlights the urgent need for global action to address the climate crisis and limit temperature rise. While the situation in the Horn of Africa remains dire, efforts to reduce emissions and support vulnerable communities can help to prevent further devastation and build resilience in the face of climate change.