Unabated global temperature rise could lead to a death toll higher than the current number of deaths from all the infectious diseases combined, new research has found. Poorer and hotter parts of the world will bear the brunt of the burden, but the impact of climate change will be felt globally.
According to a new study conducted by the Climate Impact Lab, if greenhouse gas emissions are not drastically reduced, the number of deaths as a result will potentially be higher than that caused by all infectious diseases combined. In a high-emissions scenario that results in 4.5°C of predicted warming, the scientists found that mortality rates could be as high as 73 deaths per 100,000 people by the end of this century.
By comparison, the current mortality rate for all infectious diseases, including malaria, tuberculosis and HIV/AIDS, stands at 74 deaths per 100,000 people globally.
Researchers calculated the figures using a dataset of global deaths and temperature records from 40 countries to examine the connection between the two, and looked at both direct causes such as heat stroke and indirect causes such as increased risk of heart attacks during heat waves. The data set represents the largest ever compiled on subnational human mortality around the world.
These results provide essential information for policymakers forming strategies to reduce the impacts of climate change because they capture the benefits, in terms of mortality, of reducing CO2 emissions.
The paper stressed that as temperature continues to rise, the most devastation will be felt among the world’s poorest countries. By the end of the century under a high-emissions scenario, climate change will lead to nearly 107 deaths per 100,000 people in low-income countries. This is primarily because richer countries will be able to spend substantial amounts on technologies to prevent deaths, such as cooling systems.
Age is another factor impacting mortality rates due to climate change, as this demographic is more vulnerable to indirect effects of heat and are more likely to be suffering from long-term health problems that will be exacerbated by extreme weather events.
While the outlook is dire, the scientists emphasise that climate mortality risks can be dramatically reduced if climate action is taken, and that their results can clearly demonstrate the impact that it could have. If global warming can be slowed down to 2.4°C degrees of warming by the end of the century, then the total death rate could fall by 84% compared to the high-emissions scenario.
We should be willing to pay $36.6 per ton today to avoid the future mortality consequences of climate change.
“These results provide essential information for policymakers forming strategies to reduce the impacts of climate change because they capture the benefits, in terms of mortality, of reducing CO2 emissions,” wrote the authors.
By curbing climate change and saving lives, the researchers say that huge economic costs could also be avoided. If emissions aren’t slashed, then 3.2% of the global economic output could be lost by the end of the century. Each ton of additional emissions costs US$36.60 in damage in a high-emissions scenario, they calculated.
“We should be willing to pay $36.6 per ton today to avoid the future mortality consequences of climate change,” the scientists said.
Lead image courtesy of David Gray / Getty Images.