The Sahara Desert covers an area of northern Africa larger than the lower 48 United States. And it’s growing even bigger.

Over the past century, rainfall levels have decreased along the southern edge of the Sahara. So some areas that were once semi-arid grassland have become desert.

Nigam: “The desert has expanded southward during summer by about ten percent, so it’s a fairly significant increase in the desert expanse over this 93-year period that we analyzed.”

Sumant Nigam is a professor at the University of Maryland. He says decreasing rainfall is likely a result of both natural cycles and human-caused global warming.

And he says it’s a big concern in the summer months.

Nigam: “Summer being the growing season – agriculturally important season – it means that some fertile land or some land that was perhaps amenable to some kind of agricultural processes is now being taken away.

Most people in the region depend on the food they grow on small family farms. So losing farmland could have grave consequences, especially as populations continue to grow.

Reporting credit: Daisy Simmons/ChavoBart Digital Media.