This article from ars technica, about a paper from Science is worth a read. For some time now, we've been getting better at producing farming so our food production has been going up. Not, as much as it should though. Climate change has been damaging our ability to produce food, it's just that no one has noticed because the increases in productivity have more than compensated. If we didn't have climate change to deal with, it appears we would have had the equivalent of Frances annual wheat crop and Mexico's annual maize crop at the very least, in addition to what we've already been producing. It provides yet another good reason to be doing something about climate change (though it's not like there was a dearth of good reasons anyway). It would make the growing world population easier to feed and if climate change continues apace, at some point, the change will outstrip our ability to improve production, which will make food shortages all the worse.