Extreme weather has caused disasters in several countries, but the Sahara Desert has undergone an unexpected transformation—not for the worse, but by turning green.
According to a report by CNN on Sunday (Sept. 15). Normally barren, storms moved into the area and triggered major flooding.
This phenomenon is marked by the development of stormy weather when moist tropical air near the equator meets hot, dry air from the northern parts of the continent. The storm’s focal point—known as the Intertropical Convergence Zone (ITCZ)—shifts north of the equator during the summer months in the Northern Hemisphere. It typically drifts south of the equator during the warmer months in the Southern Hemisphere.
However, since mid-July, this zone has shifted farther north than usual, sending storms into the southern Sahara, including parts of Niger, Chad, Sudan, and even northern Libya, according to data from NOAA’s Climate Prediction Center.
As a result, parts of the Sahara have received two to six times more rainfall than usual.
The transition from El Niño to La Niña has influenced how far north the ITCZ has moved this summer, said Haustein. El Niño, a natural climate pattern marked by warmer-than-average sea temperatures in the equatorial Pacific, usually brings drier conditions to the typically wet regions of West and Central Africa. La Niña, or its developing form, can have the opposite effect.
The northward shift of the ITCZ, which is causing the Sahara to green, is happening as the world gets warmer. Most climate models suggest this trend will continue.
A study published in the journal Nature in June found that the ITCZ could move even farther north in the coming decades due to rising carbon dioxide levels—a byproduct of fossil fuel pollution—leading to a warmer planet.
This shift is not only greening parts of the desert but has also disrupted the Atlantic hurricane season and brought significant consequences to several African countries over the past few months.
Countries that should have received more rainfall experienced less, as storms shifted northward. Regions like Nigeria and Cameroon, which typically get 20 to 30 inches of rain from July to September, have received only 50-80% of their usual rainfall since mid-July, according to CPC data.
Further north, typically drier regions—including parts of Niger, Chad, Sudan, Libya, and southern Egypt—have seen more than 400% of their normal rainfall since mid-July, according to CPC data.
Northern Chad, part of the Sahara Desert, usually gets just about an inch of rain between mid-July and early September.
Nearly 1.5 million people have been affected, and at least 340 people have died as a result of the floods this summer, according to a United Nations briefing.
The deadly floods have also claimed over 220 lives and displaced hundreds of thousands of people in Nigeria, particularly in the usually dry northern regions, as CNN previously reported.
Sudan was also hit by deadly flooding in late August, killing at least 132 people and destroying over 12,000 homes.
These flood events likely bear the marks of climate change, according to Haustein, who studies how climate change influences specific weather events.
As the Earth warms, it can hold more moisture, leading to wetter rainy seasons and more severe floods like those seen this season, Haustein explained.
More research is needed to determine the exact role of climate change in each flooding event, but this may be a warning of future disasters, Haustein said.
“Every individual event is influenced by climate change. Even if no single flood is directly caused by climate change, the likelihood of such events occurring is increasing.”