Africa: Climate Change Impacts
Africa: Climate Change Impacts
Africa, the world's second-largest continent, is inhabited by almost a billion people. Because of the interaction of climate change with other stresses in Africa—such as widespread poverty, population growth, acquired immunodeficiency syndrome (AIDS), and overgrazing and other ecosystem damage—it is considered to be the continent most vulnerable to the effects of climate change. Projected impacts of climate change on Africa include biodiversity loss (extinction of plant and animal species), diminished agriculture with increased hunger, increased disease, forced migration of populations (especially out of the Sahel), and more. About 70% of Africa's population lives by farming, often subsistence farming, with the poorest members of society tending to be most dependent on agriculture.
Historical Background and Scientific Foundations
For approximately 500 years, from the fifteenth century to the mid-twentieth century, Africa was the source of millions of slaves for European and Arab raiders, resulting in many millions of deaths. In the nineteenth and twentieth centuries, Africa was dominated by European colonial powers, who divided most of its territory and exploited the region's resources without regard for its inhabitants. One result of this colonial history is a legacy of weak social networks, chaotic political systems, and poverty. These problems have ongoing effects on ecosystems and impact the region's ability to adapt to climate change.
In 2007, the Intergovernmental Panel on Climate Change (IPCC), the world's largest and most authoritative body of climate and weather scientists, released the report of its Working Group II, Climate Change 2007: Impacts, Adaptation and Vulnerability. The report noted the following points, among others, about the impacts of climate change on Africa:
- Africa is one of the continents most vulnerable to global warming. This situation is made worse by Africa's low capacity to adapt to climate change. Poor access to loans, markets, technology,
- machinery, and the like make Africa more vulnerable to climate change. A variety of disasters and conflicts already plague the region, including wars, over-grazing and other forms of ecosystem degradation, and AIDS. (About 25 million persons were infected with the human immunodeficiency virus [HIV] in Africa as of 2007, and about 2 million Africans die of AIDS each year.)
WORDS TO KNOW
BIODIVERSITY: Literally, “life diversity”: the number of different kinds of living things. The wide range of organisms—plants and animals—that exist within any given geographical region.
GREENHOUSE GASES: Gases that cause Earth to retain more thermal energy by absorbing infrared light emitted by Earth's surface. The most important greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, and various artificial chemicals such as chlorofluorocarbons. All but the latter are naturally occurring, but human activity over the last several centuries has significantly increased the amounts of carbon dioxide, methane, and nitrous oxide in Earth's atmosphere, causing global warming and global climate change.
INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE (IPCC): Panel of scientists established by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) in 1988 to assess the science, technology, and socioeconomic information needed to understand the risk of human-induced climate change.
MALARIA: Group of parasitic diseases common in tropical and subtropical areas. According to 2004 statistics from the U.S. Centers for Disease Control and Prevention (CDC), approximately 300 million cases occur annually worldwide, and an estimated 700,000 to 2.7 million persons die of malaria each year. About 90% of these deaths occur in sub-Saharan Africa, with the majority being children. In 2002, in the United States (even though malaria has been eradicated from the country since the early 1950s), 337 cases of malaria, including eight deaths, were reported to the CDC.
SAHEL: The transition zone in Africa between the Sahara Desert to the north and tropical forests to the south. This dry land belt stretches across Africa and is under stress from land use and climate variability.
SUBSISTENCE FARMING: Agriculture carried on for the sake of the food it produces, rather than to produce crops to sell for cash.
IN CONTEXT: DISEASE PERILS
Epidemics can decimate the families and economics of a region. Epidemics of disease disrupt national economies, as large numbers of people become unable to work or care for themselves. For example, according to World Health Organization (WHO) estimates, in 2004 the number of healthy years of life lost due to premature death and disability caused by trypanosomiasis was 1.5 million. Trypanosomiasis (also known as African sleeping sickness because of the semi-conscious stupor and excessive sleep that can occur in someone who is infected) is an infection passed to humans through the bite of the tsetse fly. Thus, it is a vector-borne disease. If left untreated, trypanosomiasis is ultimately fatal. Since many African regions are still agricultural, the rural-based disease affects those who are most important to the economy. Of the 48,000 deaths that occurred in 2004, 31,000 were males, who are often the working family members.
Trypanosomiasis is a major health concern in approximately 20 countries in Africa. The WHO estimates that over 66 million people are at risk of developing the disease. However, fewer than 4 million people are being monitored and only about 40,000 people are treated every year. The proportion of people being monitored or treated is smaller than other tropical diseases, even though trypanosomiasis can increase to epidemic proportions and the death rate for those who are not treated is 100%.
The resurgence of trypanosomiasis during the 1970s was due to the interruptions in the monitoring of disease outbreaks, the displacement of people due to regional conflicts, and environmental changes. These problems are ongoing. In particular, the documented warming of the atmosphere will make Africa even more hospitable to the spread of the territory of the tsetse fly, which could increase the geographical distribution of trypanosomiasis.
- African farmers have been adapting to current climate change, but these adaptations may be overwhelmed by future climate change. Food production may be “severely compromised” (in the IPCC's words) in many African countries. About one-third of all income in Africa is from agriculture, with one-third of household income coming from crops and livestock. Changes in agriculture due to
loss of rainfall may be severe in some areas, especially in semi-arid areas, which are already marginal for agriculture due to limited rainfall. Semi-arid areas are projected to see a shortening of the growing season of more than 20% by 2050, according to some scenarios that address the continued emission of greenhouse gases. Large areas of land where agriculture is now marginal may be forced out of production.
- The water shortages faced by some countries will be made worse by climate change, while some countries that do not now have water shortages will be at risk for them. This is particularly true of northern Africa. About one-fifth of Africa's population—about 200 million people—presently experiences severe water shortages. By the 2050s, the population at risk for increased water stress—inadequate access to good-quality water for household use and agriculture—could rise to 350–600 million.
- Changes in African ecosystems are already seen, especially in southern Africa. About 25–40% of mammal species in national parks in sub-Saharan Africa (south of the Sahara desert) may become endangered in the twenty-first century.
- Human health will be threatened by global warming. For example, increased rainfall in eastern Africa will increase the land area where malaria is endemic. Presently, malaria kills about 900,000 people annually in Africa, 70% of them children. Pregnant women and children are particularly likely to be affected by climate change because of their greater vulnerability to heat, infectious diseases, and inadequate food.
Impacts and Issues
Most studies of climate impact focus on wealthier parts of the world, such as Europe and North America. For example, according to the IPCC, very little detailed information is available on the vulnerability of the energy sector (the part of the economy that produces heat and electricity) in Africa. Experts suggest that reductions of greenhouse-gas emissions in industrialized and developing countries, as well as assistance in mitigating the harmful effects of climate change, are essential to reducing climate-change impacts in Africa.
However, they note that it is difficult to persuade nations to modify their behavior for the benefit of others. It is likely that Africa will, due to its greater vulnerability, disproportionately experience the impacts of climate change, although its inhabitants have contributed only a tiny fraction of the greenhouse gases that are causing most of that change.
See Also Arctic People: Climate Change Impacts; Asia: Climate Change Impacts; Europe: Climate Change Impacts; North America: Climate Change Impacts; Small Islands: Climate Change Impacts; South America: Climate Change Impacts.
Parry, M. L., et al, eds. Climate Change 2007: Impacts, Adaptation and Vulnerability: Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.
Thomas, David S. G., et al. “Remobilization of Southern African Desert Dune Systems by Twenty-First Century Global Warming.” Nature 435 (June 30, 2005): 1218–1221.
Desanker, Paul. “Impact of Climate Change in Africa.” WWF-UK, August 2002. < http://www.wwf.org.uk/filelibrary/pdf/africa_climate_text.pdf> (accessed September 16, 2007).
“York Scientists Warn of Dramatic Impact of Climate Change on Africa” (press release). University of York (United Kingdom), June 9, 2005. < http://www.york.ac.uk/admin/presspr/pressreleases/climateafrica.htm> (accessed September 16, 2007).