Scientists are sounding the alarm about the extreme increases in the Earth’s temperature. A new report by UNICEF warns that 2022 could be the “coldest year of the rest of our lives”. Heatwaves are becoming stronger and lasting longer. These increases are threatening the limits of human survival.
The African continent is particularly at risk – it’s heating up more, and faster, than any other region in the world. By 2030, up to 118 million extremely poor people in Africa will be subject to the devastating impacts of drought and intense heat. This has huge implications for human health, from the spread of disease to heat stress.
Experts writing for The Conversation Africa have explored these issues in a number of articles. We’ve collected four of these important reads here.
1. Surviving extreme heat
The general limit of heat we should live in is 35°C wet-bulb temperature, which is a measure of both air temperature and humidity. Beyond this, the body struggles to cool itself.
Extreme heat is a serious health hazard. Many of the temperatures being recorded in Africa now, and those projected for the next decade, are already close to the limits of human survival, or “liveability”.
Health experts Abdu Mohiddin, Christopher Jack, Evans Kituyi, Kristie Ebi, Matthew Chersich and Stanley Luchters provide insights into who’s most at risk from extreme heat, and what must be done to mitigate it.
2. Vulnerable living spaces
Cities are recognised as areas particularly vulnerable to the effects of heat on health. This is because urbanised areas experience higher temperatures than less-urbanised or rural areas.
Within cities, people living in informal settlements are particularly at risk of increased temperatures. Lorena Pasquini, a climate change adaptation researcher, reveals why. She carried out research in informal settlements in Tanzania’s capital, Dar es Salaam, and explains that the structures people live in have features that either increase temperatures or lack features that would cool them down.
In addition, inadequate or absent planning means that housing is too densely packed so that air can’t circulate.
3. Children at risk
Children, especially newborn babies, are at particular risk of heat stress. This is because they’re less able to control their body temperature. They can easily become dangerously hot or cold.
Climate experts Cathryn Birch, John Marsham and Sarah Chapman estimate that between 2011 and 2020, there were between 12,000 and 19,000 heat-related child deaths per year in Africa.
Climate change accounts for about half of these deaths. The additional deaths due to climate change cancel out the recent reduction in heat-related deaths that was achieved through developmental improvements.
This research underscores the urgent need to reduce emissions and the impact of heat on babies and children.
4. Growing risk of mosquito-borne diseases
Extreme heat can have a direct impact on people’s health, for example by causing heat exhaustion or heat strokes. High temperatures also have an indirect impact on health – for example through disease transmission. Researchers have warned that climate change will lead to an increase in the number of people exposed to new mosquito-borne diseases.
Mosquitoes are among the deadliest animals in the world. Beyond being annoying, these insects transmit diseases such as malaria, zika virus and yellow fever.
Shüné Oliver, a biochemist, and her colleagues at South Africa’s National Institute for Communicable Diseases have been tracking Anopheles arabiensis, one of the mosquito species that transmits malaria.
Their research shows that insecticide-resistant mosquitoes can withstand extreme heat. This will complicate malaria control.