The mean air temperature in Africa has increased by about 1°C/1.8°F since 1901, slightly above the global land mean. Outside of the mountainous regions, temperature increases have occurred everywhere, if not uniformly (as much as 3°C/5.4°F in parts of the Sahel). Precipitation patterns are more complex. Rainfall has decreased everywhere except in the tropical rainforest zone around the equator, where seasonally it has increased.
Climate data is very sparse across the entire continent. Information on trends is limited, though predictive models are easier to find. Those models, based of course on the historical information, show a future consistent with the record from the 20th and early 21st centuries: warming and drying in the subtropics of Africa, and an expanded tropical zone.
Agriculture in much of Africa is localized, relying on rain, not groundwater-fed irrigation systems. As a result African farms outside the tropics are especially vulnerable to drought. Decreased rainfall will also diminish livestock production, and hunting and fishing catch. Given the social tensions in parts of Africa and weakness of several of its governments, large climate disruption of food production could lead to huge social unrest and major migrations.
As the subtropical zones become hotter and drier, the habitable coastal zones on north and south have been increasingly squeezed, and that trend is likely to continue. The Sahara has grown to north and south since the early 1900’s and will almost certainly expand further. Africa’s present and future climate reality is severely constrained by water scarcity.
Tomorrow: introduction to South Africa.
Be brave, and be well.
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