Sunday, November 3, 2013

United Nations: adapting to climate change will cost Africa $35 billion snnually. Until it costs more

Marc Herman in Pacific Standard: A study out from the United Nations Environment Program (UNEP) has tried to calculate the cost for African states to adapt to a rise in the world's average temperature by the turn of the next century. "Warming limited to below 2°C still implies major adaptation costs for Africa. A 4°C of warming by 2100 will hit the continent very hard." What does "hit the continent very hard" mean, specifically?

The water picture is particularly chaotic. According to the report, the average sea rise along the continent's coast would be one meter, which is 10 percent higher than the expected increase globally. Delta regions in Egypt, Cote d'Ivoire, Mozambique, Nigeria, and Tunisia are among the countries expected to take the brunt of the ocean rise. In those places, whole cities, including capitols and major ports, would face Hurricane Sandy-esque conditions, with human and economic impacts to match.

At the same time the sea encroaches, rainfall will crash and aquifers become unreliable. If temperatures rise four degrees by 2100, rain will fall by 30 percent in the continent's south and 20 percent in North Africa, the U.N. office estimates. Wells for drinking water and crop use become dramatically insufficient at that rate. "Parts of north, west and southern Africa may see decreases in groundwater recharge rates of 50–70 percent as well as reductions in annual river discharge."

Urban effects lean toward disease and migratory stress. The report notes that cities tend to be hotter than rural areas when faced with similar weather, a condition called the "urban heat island effect." (If you've ever gone to New Jersey from Manhattan or to Virginia from Washington, D.C., in August, you've experienced this.) That would become more pronounced as average temperatures increased, particularly in summer....

Dunes of the Sahara in Niger, shot by Michael Martin, under the Creative Commons Attribution-Share Alike 3.0 Unported license

No comments: