In an aerial view, dry cracked earth is visible between the rows of an almond orchard in Firebaugh, California, on Tuesday.

As California enters an extreme drought emergency, water is starting to become scarce in its Central Valley, one of the most productive agricultural regions in the world.

Farmers are facing a shortage of water to use on their crops as wells and reservoirs dry up.

Some are pulling out water-dependent crops, like almonds, or opting to leave hectares fallow.

"It's a really sad day," said Fresno County farmer Joe Del Bosque, who has destroyed 40ha of organic asparagus so he can divert precious water to more valuable melons. "The water is so uncertain this year. We didn't think we'd have enough to carry it through."