The Sahara Desert, one of the most defining features of the African continent, is also one of the most problematic when it comes to climate change. As the Earth’s temperature and weather patterns change due to human behavior, the desert will be enormously affected, impacting the lives of those living on settlements along its borders. Here are 12 consequences of climate change in the Sahara Desert, and what is being done about it.
Sources: AstroBio.net, NYTimes.com, WSJ.com, LiveScience.com, NationalGeographic.com, Allianz.com, AmericanScientist.org, ThinkProgress.org, News.Stanford.edu, TheEcologist.org, TheDailyBeast.com,
Scientists have begun to see a pattern of increased rainfall in the Sahel, the semi-desert zone bordering the Sahara to the south, as hotter air has more capacity to hold moisture, creating more rain. This has been supported by huge increases in vegetation in areas of the Sahel, including central Chad and western Sudan.
If the climate models that predict a shrinking desert prove correct, this translates to a huge revitalization of communities along the desert borders that have suffered drought conditions for milennia – impeding their ability to farm. This would echo conditions of the Sahara some 12,000 years ago, when it was a lush savanna before transforming into the desert as the result of natural climate change.
While some areas of the Sahara region have begun to green, others have experienced devastating encroachment of the desert into previously fertile areas. For instance, Dakar, Senegal’s capital city, has begun to experience horrible sandstorms that clog the air, and its rainy season has already been shortened by two months.
The population on the southern edge of the Sahara tripled since the 1950s, as did the number of livestock grazing the area. Goats have particularly destructive grazing habits. Unlike native camels or gazelles, goats rip out entire plants, roots and all, killing vegetation completely rather than giving it the change to regrow.
If the destructive trends that contribute to desertification continue unabated, the U.N. estimates that two thirds of Africa’s arable land could be lost to desert by 2025. Given the size of the Sahara, desertification affects about 40 percent of the continent overall.
The Great Green Wall initiative aims to plant a wall of trees and vegetation from coast to coast across Africa to keep the Sahara from continuing to spread. Should the wall be completed as planned, it will be 4,300 miles long and nine miles wide, cutting through 11 countries. The African Union approved the Great Green Wall initiative in 2007, and planting began in some countries in 2008.
In addition to slowing desertification, the trees and vegetation planted in the Great Green Wall initiative were also selected for their ability to provide fruit and vegetables in regions that often struggle with food insecurity issues.
As a compromise with local communities, some protected areas of the Green Wall are opened up in harsh years as a type of emergency forage bank for hungry animals to graze to prevent them from starving. This has helped garner community support for the initiative.
Along with the Great Green Wall initiative, other projects have sprung up around the continent with similar goals. The Sahara Forest Project, for instance, is working to create large desert oases using solar power, vegetation, saltwater greenhouses, and algae cultivation to grow produce and bio fuels.
For the Great Green Wall initiative in Senegal, 400 people are employed in eight nurseries to help with germination and tending of seedlings. In August each year, another 1,000 workers are tapped to help plant the rows of seedlings, numbering almost 2 million, to give them time to set before the rainy season.
Approximately 80 percent of the trees planted as a part of the Great Green Wall and other initiatives survive, and sensors have been planted to record the temperatures of the area. Preliminary results show clumps of just four-to-eight trees can impact temperatures by helping moderate daily temperature extremes. They also help prevent soil erosion, reducing the potential for sand winds and sandstorms.
Source: NYTimes.com
African easterly waves are the weather systems that form over Northern Africa during the summer season and travel east to west towards the Atlantic Ocean. Climate models predict a strengthening of these waves that travel near the border of the Sahara and the Sahel. Precipitation in drought-prone regions will be affected, with more dust picked up out of the desert and transported across the ocean. This could impact rainfall and air quality in the Americas. African easterly waves are critical in determining rainfall in West Africa, as well as climatic patterns across the Atlantic all the way to the Americas.