The Sahara, the world’s biggest hot desert, the third largest desert overall, is getting even bigger. In fact, it is currently about 10 percent larger than it was nearly a century ago, and scientists suggest that climate change is partly responsible.

To qualify as a desert, a region has to see 4 inches (100 mm) or less of rainfall per year. The Researchers looked at rainfall data from across Africa recorded between 1920 and 2013. They found that more of the area around the Sahara — about 10 percent more — qualified as desert, making the largest hot desert even larger.

At the southern border of the Sahara lies a semi-arid grassland known as the Sahel. It’s a buffer zone between the harsh Sahara and the fertile savannas in southern Africa, particularly Sudan and Chad. Lake Chad, for example, has been getting smaller due to climate fluctuations and because its used to irrigate crops. The lack of rainfall does not help the situation.

The study also points out that it’s probably not just the Sahara that’s expanding. Deserts around the world are likely experiencing the same climate changes and growing larger as well. Deserts are all formed pretty much the same way: Warm air rises in the tropics, which are near the equator, then spreads toward the poles, a frightening prospect fot the locals.

https://www.livescience.com/62168-sahara-desert-expanding.html