There's a new warning this week about the likely impact of climate change on the world's food supply. It's part of a leaked draft report from the U-N's climate science panel, the I-P-C-C.
The draft says climate change is likely to cut global crop yields over the next few decades even as demand for food keeps growing fast, creating a potentially dangerous gap.
Co-author David Lobell of Stanford's Center on Food Security and the Environment says the overall trends are clear but that scientists are still trying to get a fix on where the changes might be most dramatic.
He spoke with The World's host, Marco Werman.