The Paris agreement on climate change, pioneering as it is, is based on a somewhat arbitrary warming temperature limit of 2°C (3.6°F). This was chosen partly because it was an easily digestible number for the politicians and the media coming to terms with the target. Many developing and low-lying nations, in fact, hope that the warming is restricted to 1.5°C (2.7°F), with anything in excess of this deemed to be a guarantee of their doom.
Several studies have shown that this will certainly be the case. Several Pacific islands have already been swallowed up by the rising sea, and within the next century, large swaths of the Middle East and North Africa will be so hot that they will practically be uninhabitable.
A new study published in the journal Environmental Research Letters has now revealed that the entire African continent will experience extreme heat waves every single year by 2040. This will definitely happen if no action is undertaken to mitigate greenhouse gas emissions, but even if the Paris agreement is adhered to, it may still occur.
An international consortium of researchers analyzed the severity of temperature extremes in Africa from 1979 to 2015; using this assembly of heat waves, they were able to make robust projections for Africa’s thermal climate for every year up to 2075. Within the next 20 years, it looks like the continent will experience prolonged and frequent heatwaves, and by the end of the century, there could be four heat waves every single year.
“Africa is one of the most vulnerable continents to climate change and even a modest rise in average global temperature could have severe consequences for the people living there,” Jana Sillmann, a senior researcher at the Center for International Climate and Environmental Research (CICERO), said in a statement.
Projections for future “unusual heat waves,” as predicted under both the business-as-usual model (RCP8.5) and the Paris agreement model (RCP4.5) The higher the HWMId, the more severe the heatwave. Russo et al./Environmental Research Letters
Nestled between the Tropic of Cancer and the Tropic of Capricorn, almost all of the African continent receives high amounts of solar radiation, and heat waves can occur in both summer and winter. The team wanted to know how man-made climate change might affect the occurrence of heat waves here, so they decided to use the relatively new Heat Wave Magnitude Index daily (HWMId) metric.
For this study, the metric assessed regional temperatures in moving blocks of three months to determine whether or not a prolonged spike in temperatures was occurring. Those that had not just exhibited particularly high temperatures for the season they were occurring in, but that also had a huge spatial extent and occurred more than once in a year, were highlighted as “unusual heat waves,” or UHWs.
After cataloging all pre-existing heatwaves from 1979 until the present, they used cutting-edge climate change modeling software to predict what a future Africa would be like, both under the Paris agreement scenario and the “business-as-usual” model, where no mitigation occurs. Even under the most optimistic scenario, their models suggest that there could be an UHW during every season of every year by the end of the century – the only difference is that, by then, they will be considered “normal” heat waves.
As the study notes, “Africa is likely to pay a heavy price for global warming, despite having contributed little to its cause.” Sadly, even with the Paris agreement in place, it seems highly likely that climate change will bring about untold humanitarian crises there, and make climate refugees more common than those fleeing persecution or economic turmoil.
