Burning fossil fuels releases a lot of carbon dioxide to the atmosphere. Plants use carbon dioxide to grow, so some people mistakenly assume that rising CO2 levels will be uniformly good for crops.

But scientists warn that the reality is more complex.

Kenneth Boote is a professor emeritus at the University of Florida.

He says more CO2 can boost photosynthesis for crops, especially wheat and rice.

Boote: “And that’s good news. It gives you increased production.”

But he says if CO2 levels continue to rise, the rate at which crop yields increase levels off.

And he warns that adding carbon dioxide to the atmosphere fuels global warming. So in many regions, the benefits could be outweighed by the harmful effects of drought and heat.

Models show that in mid- and low-latitude areas, where most of the world’s breadbaskets are located, the yields from many crops will likely decrease over time.

Boote: “There’s a very slow decline initially … but it becomes more severe the more the temperature goes up.

Intensifying disasters such as floods and fires can also devastate harvests.

So despite some benefits, adding too much carbon dioxide to the atmosphere can threaten global food supplies.

Reporting credit: Sarah Kennedy/ChavoBart Digital Media


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