Climate change may turn Africa’s arid Sahel green - researchers

LONDON (Thomson Reuters Foundation) - One of Africa’s driest regions - the Sahel - could turn greener if the planet warms more than 2 degrees Celsius and triggers more frequent heavy rainfall, scientists said yesterday.

The Sahel stretches coast to coast from Mauritania and Mali in the west to Sudan and Eritrea in the east, and skirts the southern edge of the Sahara desert. It is home to more than 100 million people.

The region has seen worsening extreme weather - including more frequent droughts - in recent years.

But if greenhouse gas emissions continue unabated, the resulting global warming - of more than 2 degrees Celsius above pre-industrial levels - could change major weather patterns in the Sahel, and in many different parts of the world, scientists say.

Some weather models predict a small increase in rainfall for the Sahel, but there is a risk that the entire weather pattern will change by the end of the century, researchers at the Potsdam Institute for Climate Impact Research (PIK) said.

“The sheer size of the possible change is mindboggling - this is one of the very few elements in the Earth system that we might witness tipping soon,” said coauthor Anders Levermann from PIK and the Lamont-Doherty Earth Observatory of New York’s Columbia University.

If the Sahel becomes much rainier, it will mean more water for agriculture, industry and domestic use. But in the first few years of the transition, people are likely to experience very erratic weather extreme droughts followed by destructive floods, the researchers said.

This level of unpredictability makes it very hard for people to plan for coming changes, they said.

“The enormous change that we might see would clearly pose a huge adaptation challenge to the Sahel,” said Levermann.

“More than 100 million people are potentially affected that already now are confronted with a (multitude) of instabilities, including war,” he said.

The region faces a range of conflicts, including some driven by groups such as Boko Haram and al Qaeda in the Islamic Maghreb.