For a long time scientists believed that rising carbon dioxide levels in the atmosphere responsible for global warming would likely offset the damage done to crops by rising temperatures. As everyone knows, photosynthesis in plants converts carbon dioxide from the air into carbon compounds for the plants and oxygen which is released to the atmosphere. Extra carbon dioxide ought to do plants some good, scientist surmised.
Now, actual open field experiments which added carbon dioxide and the expected ozone levels from increased smog show dramatic reductions in yields. This is extremely bad news, especially for countries such as India and China.
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