The Sahara Desert has expanded by about 10% since 1920, growing at an average rate of approximately 11,000 square kilometers per year.
The Sahara Desert Has Grown 10% Since 1920
The Sahara Desert isn't just sitting still—it's actively growing. University of Maryland researchers analyzed nearly a century of rainfall data across Africa and discovered that the world's largest hot desert expanded by roughly 10% between 1920 and 2013. That's an area larger than the state of Montana swallowed by advancing sands.
The expansion isn't uniform throughout the year. Summer sees the most dramatic growth, with the desert's seasonal boundary pushing outward by nearly 16% during the hottest months. This means communities on the Sahara's southern edge face increasing desertification precisely when they need rainfall most for crops and livestock.
Why Is the Desert Growing?
About two-thirds of the Sahara's expansion comes from natural climate cycles—the same patterns that have caused the desert to advance and retreat over millennia. But here's the concerning part: one-third is attributable to human-caused climate change. As global temperatures rise, the subtropical desert belt is widening, pushing the Sahara both northward and southward.
The southern boundary is particularly aggressive. In Mali, the desert advances at roughly 48 kilometers per year, consuming farmland and forcing communities to migrate. The total expansion translates to approximately 11,000 square kilometers of new desert annually—that's about the size of the island of Jamaica disappearing under sand each year.
A Glimmer of Hope
Surprisingly, recent climate models suggest this trend might reverse. Research from late 2025 indicates the Sahara could receive up to 75% more precipitation by the latter half of this century, potentially greening portions of the desert. Whether this happens depends largely on global efforts to address climate change.
Meanwhile, 22 African nations are constructing the Great Green Wall—an 8,000-kilometer barrier of trees and vegetation designed to halt the desert's southern advance. It's one of humanity's most ambitious environmental projects, attempting to hold back the sands through ecological restoration rather than concrete barriers.
The Sahara's expansion serves as a visible reminder of our changing climate. Unlike abstract temperature charts, a growing desert is something you can see from space, with real consequences for millions of people living along its shifting borders.