|(c) AAAS 2011|
As reported by the National Science Foundation (USA), the latest edition of Science (25th February 2011) includes a fascinating piece titled 'How Severe Can Climate Change Become?'
An international team of scientists led by Curt Stager of Paul Smith's College, New York have been examining cores of sediments derived from Lake Tanganyika, and other locations across Africa. These sediment cores can be used to produce models of past climate (palaeoclimate), giving an indication of what conditions were like tens of thousands of years ago.
Results of this research found that around 15-18000 years ago a megadrought occurred in which Lake Victoria (below right) dried as did other lakes and major rivers such as the Nile. The effects of this would be devastating for huge numbers of people. It is conjectured that the cause of this megadrought was a warming event, and the melting of huge amounts of ice, releasing significant amounts of water into the North Atlantic, altering global climatic patterns.
The report highlights that there is much less ice today that could melt and enter the North Atlantic, and hence it is unlikely that a megadrought on the same massive scale could occur, however the results give an indication of some of the effects global warming could have on developing nations such as Tanzania, Uganda, Ethiopia etc. Droughts much smaller than the megadrought reported in this paper do and will have a significant effect on the lives of many poor communities.
You can find the press release for this article here