Climate catastrophe threatens Africa
Deadly epidemics， ruined crops and the extinction of some of Africa's legendary wildlife are some of the potential consequences of global warming for Africa， yet its nations are among the least equipped to cope.
“It is our vulnerability that sets us apart from developed nations，” said Luanne Otter， a researcher at the University of the Witwatersrand.
Surface temperatures rose about 0.6 degree Celsius in the 20th century - the largest increase in 1，000 years， according to the Intergovernmental Panel on Climate Change with 1998 the warmest year on record and this year could be even hotter.
Climate experts say the trend will continue as long as carbon dioxide from burning fossil fuels and other gases keep building up in the atmosphere， trapping heat like a greenhouse.
African nations account for a tiny percentage of the emissions but are already suffering the consequences， researchers say.
The ice cap is receding on Africa's highest peak， Mount Kilimanjaro. Desertification is spreading in the northwestern Sahel region. Droughts， flooding and other extreme weather events are becoming more frequent and severe. Numerous plant and animal species are in decline.
Long-term threat
South africa's Minister for Environmental Affairs， Marthinus van Schalkwyk， urged the United States and other hold-outs to sign the Kyoto Protocol， which calls on the top 35 industrialized nations to cut carbon dioxide and other gas emissions by 5.2 percent below their 1990 levels by 2012.
But even if countries stop polluting today， researchers argue the effects will be felt for decades to come， posing what the African Development Bank has singled out as possibly the greatest long-term threat to poverty eradication efforts on the continent.
Some 770 million Africans - 63 percent - live in rural areas and about 40 percent survive on less than US$1 a day. Most are small-scale farmers. Wood is their major source of fuel and medicinal plants their main defense against disease.
Many are already subject to recurring droughts， floods and soil degradation that can wipe out their livelihoods. Any long-term changes in temperatures and rainfall could fundamentally alter the landscape in which they live and the production potential on which they depend.
Hotter， drier weather in the semi-arid west of South Africa could reduce production of maize， a staple， by up to 20 percent and generate a proliferation of pests. In the moister areas to the east， where rainfall is forecast to increase， thickets are encroaching into productive grasslands， threatening livestock and wildlife activities.
Rising temperatures at higher altitudes could also quadruple the number of South Africans at high risk of malaria by 2020.
With weather becoming more erratic， communities are finding themselves with little time to recover from one disaster before being hit with the next.
While the United States may be able to recover from Hurricane Katrina in a year or two， it could take Mozambique 10 years to recover from the catastrophic floods of 2000， says Roland Schulze a hydrologist at South Africa's University of KwaZulu-Natal.
Species disappear
Tourism is also an important driver of development in a number of African nations and most of it is nature-based.
Some species in South Africa's famed Kruger National Park are already disappearing， says Norman Owen-Smith of the University of the Witwatersrand.
Among those most at risk are the sable， tsebbebe， eland and roan antelopes， which are already at the edge of their natural ranges. As temperatures rise and rainfall becomes more erratic， they will want to push east toward the more humid coastline but are blocked by Kruger's fences.
The east African coral reefs have already suffered major bleaching events linked to increasing water temperatures and light， including one in 1998 resulting in 75 percent to 77 percent mortality. Some experts fear that could become the norm within the next half century.
Many argue it is only by rethinking conservation policies that species will be preserved. Corridors will have to be created to allow animals to migrate toward their favored climatic zones， or they may have to be translocated to new habitats.
A number of southern African countries have already agreed to open their borders to trans-frontier parks.
Early warning systems and disaster management plans also will need to be set up， new water sources explored， and decisions made about what crops to farm and how best to allocate fishing rights.
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