shows that the effects of climate change on food production around the world could lead to more than 500,000 deaths by the year 2050. Climate-related impacts on agriculture could lead to an overall global decline in food availability, forcing people to eat fewer fruits and vegetables and less meat. And the public health impacts of these changes could be severe.
The researchers decided to explore not only how climate-induced changes in agricultural production will affect human food consumption, but also how these dietary changes might influence human mortality. They used an agricultural model to simulate the effects of future climate change on global food production and consumption. They assumed a severe climate change scenario, one in which global air temperature by 2050 is about two degrees higher than it was in the time period between 1986 and 2005. They then used a health model to predict the way these changes in food production and consumption would affect human health. They compared all of these effects to a reference scenario, which assumes a future with no climate change.
If no climate change was to occur, the model predicted that global food availability would actually increase by 10.3% by the year 2050. But with the effects of climate change the model predicted that global food availability would be 3.2% lower than was predicted in the scenario with no climate change. Specifically, it found that people would eat 4% less fruit and vegetables and 0.7% less meat.
If there was no climate change, the health model found that the projected future increases in global food availability would actually save nearly 2 million lives in 2050 compared with conditions in 2010. But the model predicted that the effects of climate change will reduce the number of lives saved by about 28%, translating into about 529,000 deaths that would not have occurred if there was no climate change.
The researchers found that by applying a moderate climate change scenario, instead of a severe one, the number of climate related deaths fell by about 30%. And in a scenario that assumed highly stringent mitigation efforts, the number of deaths fell by more than 70%.
The food-related deaths would be caused by two major factors: people not getting the right type of nutrition, and people simply being underweight. The majority of all the predicted deaths were found to be caused by the nutrition factors, mostly by people being forced to eat fewer fruits and vegetables. Overall, the most climate-related deaths were seen in the Western Pacific and Southeast Asia—particularly in China and India.