New research investigating the transition of the Sahara from a lush, green landscape 10,000 years ago to the arid conditions found today, suggests that humans may have played an active role in its desertification.
The desertification of the Sahara has long been a target for scientists trying to understand climate and ecological tipping points. A new paper published in Frontiers in Earth Science by archeologist Dr. David Wright, from Seoul National University, challenges the conclusions of most studies done till date. The studies point to changes in the Earth's orbit or natural changes in vegetation as the major driving forces.
Growing agricultural addiction had a severe effect on the region's ecology. As more vegetation was removed by the introduction of livestock, it increased the albedo (the amount of sunlight that reflects off the earth's surface) of the land. This influenced atmospheric conditions sufficiently to reduce monsoon rainfall. The weakening monsoons caused further desertification and vegetation loss, promoting a feedback loop which eventually spread over the entirety of the modern Sahara.
With approximately 15% of the world's population living in desert regions, Wright stresses the importance of his findings. "The implications for how we change ecological systems have a direct impact on whether humans will be able to survive indefinitely in arid environments."
Content source: Sciencedaily