The world’s leading climate scientists will meet this month in Paris at the Congress of the Parties 21 (COP21) to hammer out an international agreement to attempt to keep global warming below 2° C compared to pre-industrial levels. The 2° C target was chosen because it represents “the maximum allowable warming” to avoid dangerous man-made interference in the climate.
The UK Met Office announced earlier this month that average global temperatures had already increased by one degree above pre-industrial levels. This was based on a dataset jointly run by the Met Office and the climate research unit at the University of East Anglia.
But these temperature increases will not be uniform: some places will record greater rises in temperature than others. The difference in temperatures is one of the reasons why many scientists think Africa would be hardest hit by climate change.
UN reports stated risk
“The idea that Africa would be the hardest hit started in the UN’s [Intergovernmental Panel on Climate Change] third assessment report in 2001… and the fourth report allowed this conclusion to be drawn,” Guy Midgley, a Stellenbosch University scientist involved in producing the reports, told Africa Check. “It’s pretty much become embedded in the global change common understanding.”
The United Nations’ Intergovernmental Panel on Climate Change is the major repository of climate research and technical information drawn from scientists across the world. It has produced five assessment reports on the state of climate change, starting in 1990, with the latest one published in November 2014. Midgley was part of the international team that shared the Nobel Peace Prize in 2007 for producing the fourth assessment.
The UN’s third report stated, “Africa is highly vulnerable to the various manifestations of climate change”.
In the fourth report (2007), this became: “Africa is likely to be the continent most vulnerable to climate change. Among the risks, the continent faces are reductions in food security and agricultural productivity, particularly regarding subsistence agriculture, increased water stress and, as a result of these and the potential for increased exposure to disease and other health risks, increased risks to human health.”
Midgley said that after the strong statement about Africa’s vulnerability, “[the fourth report] then goes on to list a range of adverse impacts which, taken together, have led to the conclusion that Africa will be the hardest hit”.
Following the fourth report, the African Ministerial Conference on the Environment (AMCEN) compiled a factsheet for the United Nations Environmental Programme. It said: “No continent will be struck as severely by the impacts of climate change as Africa. Given its geographical position, the continent will be particularly vulnerable due to the considerably limited adaptive capacity, exacerbated by widespread poverty and the existing low levels of development.”
However, this statement was compiled by ministers and not scientists.
‘Africa already quite hot’
While scientists and policymakers agree that African countries will be vulnerable to climate change for myriad reasons, there are still many gaps in our understanding of exactly how climate change will affect different parts of the world, different places within the different continents and to what extent.
Climate scientist Dr Bob Scholes is more sceptical than Midgley about the claim that Africa will be the continent hardest hit by climate change. Scholes, a distinguished professor at the University of Witwatersrand’s Global Change and Sustainability Research Institute, is another author of the Intergovernmental Panel on Climate Change’s assessment reports.
“The claim is based on two things: geographically and climatically Africa is exposed,” he told Africa Check. “Africa in general is already quite hot. Heat it up more and it’s just downhill for animal production, plant production and human health.”
However, other parts of the world are also quite hot and have their own vulnerabilities. And there are a number of regions within the African continent.
“In general, I would support the argument that Africa is vulnerable. But ‘the most vulnerable’? That gets into [the realm of] hyperbole,” Scholes said.
A geographic disadvantage
One of the reasons that African countries are vulnerable to climate change is the continent’s geography.
“Africa straddles the tropics with vast semi-arid regions on either side,” said Midgley. These arid and semi-arid areas are likely to see higher temperature increases than other areas, skewing the average temperature rise for the continent.
The UN’s fifth assessment report explained that it is “likely that land temperatures over Africa will rise faster than the global land average, particularly in the more arid regions, and that the rate of increase in minimum temperatures will exceed that of maximum temperatures.”
Drastic temperature increases between 1961 and 2010
Additionally, research by a team of international and South African scientists published earlier this year found that parts of subtropical and central tropical Africa had already shown drastic increases in temperature between 1961 and 2010.
“Over these regions, temperatures have been rising at more than twice the global rate of temperature increase,” the researchers noted.
Temperatures are projected to increase in these areas during this century “with plausible increases of 4 to 6° C [relative to the present day climate] over the subtropics and 3 to 5° C [relative to the present day] over the tropics by the end of the century”. This would happen, the researchers said, in the UN’s “low-mitigation scenario” – where countries put few measures in place to stop climate change.
Principal researcher and study leader, Dr Francois Engelbrecht from South Africa’s Council for Scientific and Industrial Research, said in September: “If negotiations [in Paris] fail to ensure a high-mitigation future, we are likely to see rapidly rising surface temperature across the continent…
“For many regions, the impact of temperature increases on the agricultural and biodiversity sectors may be significant, stemming from temperature-related extreme events such as heat waves, wild fires and agricultural drought.”
Temperature only one element of vulnerability
Temperature increase is only one of the variables determining a country or a continent’s vulnerability, as wealth and infrastructure, among other things, also help to determine its ability to adapt to climate change.
“Australia is also beset by a very dry portion of its continent,” noted Midgley. “But from a vulnerability and exposure point of view, Africa is more vulnerable because of poverty.”
Or as the third assessment report puts it: “The adverse impacts of climate change are expected to fall disproportionately upon developing countries and the poor persons within those countries.”
‘We need an operating manual for the planet’
While scientists like Midley and Scholes may disagree about the extent of Africa’s vulnerability, there is no doubt among the thousands of scientists that contribute to the UN assessment reports that climate change is real and driven by human activities. However, more scientific research needs to be undertaken to understand how ecosystems will be affected.
“We don’t have an operating manual for the planet,” Midgley said, “and we need one.” – 25/11/2015
Sarah Wild is a multi-award-winning science journalist and author. Find her work at www.wildonscience.com. How a country’s poverty levels, water sources and agricultural production influence its vulnerability to climate change will be discussed in her next factsheet on this topic.