From our community:
“The trends in Africa of hot summers getting hotter and rainy seasons drying out are linked with factors that include increasing greenhouse gases and aerosols in the atmosphere. These trends also have a devastating effect on the lives of African people, who depend on agriculture-based economies." Ming Cai, program director in the National Science Foundation's Division of Atmospheric and Geospace Sciences
Researchers from the University of Maryland recently had their study on African desertification published in the Journal of Climate. The research data determined that the Saharan desert has expanded 10% since 1920. The study indicates that the trend of the expansion is worse in the summer, resulting in a 16 percentage increase in the desert seasonal average. The results will have “far-reaching implications” for the Sahara, as well as other deserts such as the Gobi in China, as climate change continues to wreak havoc throughout the world. The unsustainable world population increases, and the loss of even more arable land which receives rainfall to support the growing of food crops, will have horrifying implications for humanity.
It is important to point out that Africa is the continent least responsible for fossil fuel greenhouse gas emissions, but is the most at threat to it’s effects. It is a massive land mass with many climate zones that are vulnerable to warming temperatures. And as an aside, there is even mounting evidence that the continent may be splitting in two.
The Thomson Reuters Foundation reports on the expanding Saharan Desert:
LONDON, March 29 (Thomson Reuters Foundation) - The Sahara desert has expanded by 10 percent in the past century - partly because of climate change - with far-reaching impacts on communities surrounding it, researchers said on Thursday.
Sudan, Chad, Mauritania and Libya are some of the countries which will bear the brunt of the desert's expansion, researchers at the University of Maryland said.
Two-thirds of the desert's growth is a result of natural climate cycles, while the remaining one-third stems from climate change, the researchers said in a report published in the Journal of Climate on Thursday.
"This is a natural disaster unfolding slowly," said Sumant Nigam, a professor at the University of Maryland.
"Desert advances don't get the same headlines for relief" as other major disasters like hurricanes, Nigam told the Thomson Reuters Foundation.
The authors note that the research focused only on the Sahara, but with climate change, other deserts are likely to expand as well.
Darryl Fears of the Washington Post, expands on the story noting that the researchers say that it is not the spreading of the desert that is the most chilling finding of the study. But it’s the timing. “It is happening during the African summer, when there is usually more rain. But the precipitation has dried up, allowing the boundaries of the desert to expand”.
Deserts form in subtropical regions because of a global weather circulation called the Hadley cell. Warm air rises in the tropics near the equator, producing rain and thunderstorms. When the air hits the top of the atmosphere, it spreads north and south toward the poles. It does not sink back down until it is over the subtropics, but as it does, the air warms and dries out, creating deserts and other areas that are nearly devoid of rain.
“Climate change is likely to widen the Hadley circulation, causing northward advance of the subtropical deserts,” Nigam said in a statement that announced the study.
At the same time, he said, the Sahara’s southward creep suggests that additional mechanisms are at work. One is probably the natural climate cycle called the Atlantic Multidecadal Oscillation, or AMO, in which temperatures over a large swath of the northern Atlantic Ocean fluctuate between warm and cold phases for 50 years to 70 years. The warm cycles deliver precipitation to subtropical areas, and the cold cycles keep it away. Human-caused climate change can increase the intensity and length of the drier cycle.
x xYouTube Video