Longer, hotter, more regular heat waves could have a damaging effect on life expectancy and crop production in Africa warn climate scientists in a study published in the journal Environmental Research Letters. Examining temperature data from 1979 to 2015, the researchers caution that heat waves classified as unusual today could become a normal occurrence within 20 years. This scenario could be triggered by an increase in average global temperature of 2 degrees.
Risk all year round
Located between the Tropic of Cancer and the Tropic of Capricorn, Africa experiences high levels of solar radiation all year round and heat waves can occur in any season, not just during summer months. Running climate models through to 2075, the scientists found that so-called unusual heat waves could occur as frequently as four times per year towards the end of the century. In other words, one dangerously hot spell for every season of the 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," said Jana Sillmann of the Center for International Climate and Environmental Research (CICERO), one of the institutions taking part in the study. "We need to put considerable effort into climate change adaptation to reduce the risk of extreme events such as heat waves, which are likely to occur much more frequently in the future."
Analytical approach
To crunch the numbers, the team--which also includes researchers from the Institute for Environmental Protection and Research (ISPRA) and the University of Catania, both in Italy--uses a metric dubbed the Heat Wave Magnitude Index daily (HWMId). The data format takes into account the severity of the temperature extremes as well as the number of consecutive days of hot weather. Using this approach, the group can compare heat waves occurring in different places and at different times of the year, but there are other details to factor in.
"The severity of the impact on human mortality and crop production depends on the vulnerability of the communities affected and the environmental systems," added Sillmann. "For example, the heat wave in Finland during 1972--which we have studied previously--was comparable to the period of hot weather occurring in Central Europe during 2003. However, the latter event was responsible for more deaths than the Finnish heat wave."
Full details of the team's analysis quantifying the magnitude and the spatial extent of the most extreme heat waves experienced in Africa between 1979 and October 2015 across different seasons can be found in the IOP journal Environmental Research Letters.
###
Notes to Editors
Contact
For further information please contact IOP Publishing's Senior PR Officer:
Alison Hadley
Tel 0117 930 1032
Email alison.hadley@iop.org
For more information on how to use the embargoed material above, please refer to our embargo policy.
Paper
The published version of the paper "When will unusual heat waves become normal in a warming Africa?" (Russo et al 2016 Environ. Res. Lett. 11 054016) will be freely available online 12 May. It will be available at http://iopscience.iop.org/article/10.1088/1748-9326/11/5/054016. DOI: 10.1088/1748-9326/11/5/054016.
The research team comprises:
Simone Russo (Institute for Environmental Protection and Research)
Andrea F. Marchese (University of Catania)
J. Sillmann (Center for International Climate and Environmental Research)
Giuseppina Immé (University of Catania)
Image
Figure 1 from the paper. Caption: Hot spots: spatial distribution and magnitudes of heat waves in Africa 1979-2015. (Russo et al 2016 Environ. Res. Lett. 11 054016)
About Environmental Research Letters
Environmental Research Letters covers all of environmental science, providing a coherent and integrated approach including research articles, perspectives and editorials. Go to iopscience.org/erl.
About IOP Publishing
IOP Publishing provides publications through which leading-edge scientific research is distributed worldwide. IOP Publishing is central to the Institute of Physics, a not-for-profit society. Any financial surplus earned by IOP Publishing goes to support science through the activities of the Institute. Go to ioppublishing.org or follow us @IOPPublishing.
Journal
Environmental Research Letters