Climate Change Could Cause 250K More Annual Deaths by Midcentury -- WHO

The World Health Organization predicts that an additional 250,000 people will die annually between 2030 and 2050 from conditions caused or exacerbated by climate change, the Geneva-based agency reported Thursday in an update of climate mortality estimates.

But the causes of sickness and death will shift over that period as child deaths from malnutrition and diarrheal disease decline across much of the world, while mortality rises from things like mosquito-borne malaria, heat exposure and other conditions, especially in South Asia and sub-Saharan Africa.

"Overall, climate change is projected to have substantial adverse impacts on future mortality, even considering only a subset of the expected health effects," the agency said in its latest Quantitative Risk Assessment of the Effects of Climate Change on Selected Causes of Death.  And those impacts are expected to be felt even "even under optimistic scenarios of future socioeconomic development."

At the same time, the agency said, adverse health effects from climate change "will be distributed unequally within and between populations," with wealthier countries and regions generally being better able to adapt to and mitigate against the harshest effects.

According to WHO, deaths from heat exposure will be especially pronounced over the coming decades, from 92,000 to as much as 250,000 deaths worldwide per year by midcentury, with the greatest rates of death occurring in the world's poorest regions.

Wealthy nations not spared

But the developed world won't be spared from the effects of rising temperatures, according to WHO.

"An increase in acute mortality associated with high temperatures has been observed in nearly all populations where it has been studied," the authors state.  And while human populations are largely adapted to local climates, researchers point to "an increase in mortality risk observed at both high and low temperatures in populations in temperate and cold climates ... and tropical and subtropical areas."

For example, nearly 3,000 heat-related deaths are expected annually among elderly populations in the United States and Canada by 2030, even with modest adaptation levels.  Europe, meanwhile, could see 5,500 heat-related mortalities each year through 2020.

By 2050 North American and European annual heat deaths should rise to roughly 6,100 and 10,500, respectively, even with modest adaptation.  Under a no-adaptation scenario, the projected mortalities for North America and Europe shot to 16,000 and 27,300, respectively.

Climate Change Could Cause 250K More Annual Deaths by Midcentury -- WHO