Africa as a continent will be particularly vulnerable to climate change, or so the United Nations' Intergovernmental Panel on Climate Change has been saying since 2001. Some scientists even think it will be the continent hardest hit by climate change.
As we discussed in our previous factsheet, to a large degree this is because Africa straddles the equator and has two arid and semi-arid zones on either side of the tropics.
But that’s only part one of the story. Here’s what’s set to happen when things heat up.
1. Expanding dry areas
Semi-arid areas are thought to be particularly vulnerable to climate change, says the inter disciplinary research group Adaptation at Scale in Semi-Arid Regions (ASSAR) at the University of Cape Town. That’s because these areas are already climatically stressed with high temperatures, low rainfall and long dry seasons.
“Semi-arid ecosystems are highly dynamic, with bursts of productivity in the wet season and in good years, and [with] very low productivity in dry years, often leading to temporary or longer term land degradation,” Mark New, director of the university’s African Climate Development Initiative, wrote in a note on ASSAR’s website.
The UN climate change panel noted in its fourth assessment report – published in 2007 – that by 2080 arid and semi-arid land areas in Africa are projected to increase by between 5% and 8% under a range of climate scenarios.
While climate change will not affect all regions on the continent adversely, as these arid and semi-arid areas expand, more people will fall into these zones.
2. Reliance on rain
Africa already has a number of countries facing semi-arid conditions, which poses challenges to agriculture, the UN panel’s fourth assessment report noted.
That’s because arid and semi-arid zones are characterised by erratic and low rainfall of less than 700 mm per year as well as droughts every so often, explains the community adaptation and sustainable livelihoods unit at the global non-profit International Institute for Sustainable Development.
“Regarding livelihood systems, in general, light pastoral use is possible in arid areas and rainfed agriculture is usually not possible. In semi-arid areas, agricultural harvests are likely to be irregular, although grazing is satisfactory,” the unit further says.
Climate change is expected to cause a shorter growing season and force large tracts of peripheral agriculture out of production, the fourth UN report noted.
Rain-fed agriculture accounts for 95% of farmed land in sub-Saharan Africa, according to the International Water Management Institute, a non-profit science organisation. This practice “exposes agricultural production to high seasonal rainfall variability”, according to a paper published in the journal Ecological Economics.
“Agriculture is a huge issue, especially because African agriculture is not irrigated,” says Guy Midgley, a Stellenbosch University scientist involved in writing the climate change panel assessment reports. “Also, [African farmers grow] maize, which is not well suited to African environments.” That is because the crop is sensitive to drought and extreme temperatures.
Maize production is expected to decrease as climates change, as this paper shows. While the average predicted for the continent and Latin America is a 10% decrease, some areas may see more.
Midgley describes Africa's reliance on maize as an “own goal”. “It's a tragedy and a pity that it's become entrenched.”
3. Diseases change with the climate
Changing climates are also likely to change disease patterns. Malaria is the best example of this.
The World Health Organisation estimates there were 214 million cases of malaria this year and 438,000 deaths this year. The mosquito-borne disease disproportionately affects sub-Saharan Africa, which is thought to account for 89% of malaria cases and 91% of deaths, the organisation says.
Although great strides have been made in curbing malaria – cases have fallen by 37% globally between 2000 and 2015, the WHO says – climate change may undo some of these gains.
For example, rising temperature has been shown to affect mosquito population numbers, and how the malaria parasites develop in their hosts, the authors of a paper published in the journal Science explained. They studied malaria incidence in the highlands of Ethiopia and Colombia.
The researchers further noted: “[There will be] an increase in the altitude of malaria distribution in warmer years, which implies that climate change will, without mitigation, result in an increase in the malaria burden in the densely populated highlands of Africa and South America.”
4. One catastrophe away from extreme poverty
The major reason that Africa is vulnerable to climate change, though, is that many of its inhabitants are poor.
A report published by the World Bank this year notes that rising temperatures could push another 100 million people into extreme poverty. Titled Shock Waves: Managing the Impacts of Climate Change on Poverty, the authors write: “The poor live in uncertainty, just one natural disaster away from losing everything they have.
”That is because climate-related catastrophes -- a natural disaster, a crop failure due to drought, an increase in disease or a farmer’s herd wiped out, for example -- can be too much for vulnerable people to recover from.
“Such events can erase decades of hard work and asset accumulation and leave people with irreversible health consequences,” the report stated.
Adaptation: Communities are doing it for themselves
In its fifth assessment report, the UN climate change panel noted: “Most national governments [in Africa] are initiating governance systems for adaptation.” For example, the Nile Basin Initiative bring together governments of the 11 countries through which it passes to coordinated all development activities and programmes on the river.
Climate scientist Bob Scholes, a distinguished professor at the University of Witwatersrand's Global Change and Sustainability Research Institute, believes that when people say “Africa will be hardest hit by climate change” they mean the continent has a poor capacity to cope with climate disaster.
“Government and civil society responses [in many African countries] are not as strong as in other places,” he says. “But while [that poor coping capacity] is true at government level, it is not true at village and town level.”
“Because of the lack of government support, I find African societies quite resilient.” - 8/12/2015
Sarah Wild is a multi-award-winning science journalist and author. Find her work at www.wildonscience.com.
FACTSHEET: Why do many scientists think Africa will be hardest hit by climate change?