Certain tree crops need a certain amount of cold weather every year. But scientists say that California's climate may become too warm for them to grow there.
Warming summers in Greenland have raised hopes for expansion of agriculture, but the summers have been drier, causing a decline in the number of sheep farms.
Our appetite for meat, which began growing exponentially in the U.S. after World War II, is one of the reasons farmers in the Midwest grow so much corn.
For the first time in state history, California has instated mandatory water regulations.