OROVILLE, CA - AUGUST 19: A section of Lake Oroville is seen nearly dry on August 19, 2014 in Oroville, California. As the severe drought in California continues for a third straight year, water levels in the State's lakes and reservoirs is reaching historic lows. Lake Oroville is currently at 32 percent of its total 3,537,577 acre feet. (Photo by Justin Sullivan/Getty Images)

California's grappling with one of its worst droughts in history. The water shortage is so dire, it risks affecting the entire country's food supply. As Mother Jones reported in February, California provides 99 percent of the United States' almonds, 95 percent of its broccoli, 91 percent of its grapes and 90 percent of its tomatoes. Now those and other crops are in danger: Economists say that already, the drought has taken half a million acres of farmland out of action.

Growers have responded by — what else? — pumping more water out of the ground. But that's just a temporary fix, not much better than borrowing against the future. So some in the agricultural industry are beginning to explore technology that may help them adapt to the new, arid reality. Increasingly, farmers are interested in a type of technology that's typically more associated with surreptitious marijuana growers than massive agricultural operations.

Yes, we're talking about grow lights.

Grow lights act as a supplement to sunshine in indoor environments. The basic idea has been around for decades. But recent developments have made grow lights far more energy-efficient, enabling them to be fielded on a much larger scale. And just as scientists learned to optimize crop development using chemicals and genetic modification in the last century, engineers today are discovering the same thing about sunshine. Carefully calibrate your artificial sunlight to a basil plant's precise needs and the leaves will produce different tastes. You can boost the vitamin C content of a tomato by 50 percent. You can get flowers to market more quickly by making them grow faster.

Grow lights are ideal for northern latitudes where water is abundant but sunlight is not. What does this have to do with California? As the drought continues and farmland goes fallow, some crops are going to shift north. There's some evidence this is already happening to wine grapes, said Dave Runsten, policy director for the California-based Community Alliance for Family Farmers.

"There's a lot of investment going into Washington, and areas up in that direction," said Runsten. "Some of the predictions show places like northern Idaho and Canada being good for wine production, but they're covered in forest. … The models show that a lot of places in California won't be able to grow high-value wine" for much longer.

Vineyards aren't the only ones shifting their gaze northward. So are corn and soybean growers in other parts of the United States (USA Today has a handy interactive that depicts the shift over just the last half-century).

In California, farmers are expected to lose $2.2 billion and more than 17,000 jobs to this year's water crisis alone, according to a study by the University of California – Davis. Those numbers will only worsen if the drought continues, as expected, into 2015 and perhaps 2016. Research has already linked the drought to climate change; a Stanford University team said last month that high levels of greenhouse gases in the atmosphere would likely keep triggering the high-pressure barriers that forced rainstorms away from California's farmland this year.


This trio of images obtained October 6, 2014 from NASA/JPL-Caltech depicts satellite observations of declining water storage in California as seen by NASA's Gravity Recovery and Climate Experiment(GRACE) satellites in June 2002 (L), June 2008 (C) and June 2014. Colors progressing from green to orange to red represent greater accumulated water loss between April 2002 and June 2014. California's Sacramento and San Joaquin River basins, including the Central Valley, have suffered the greatest losses, in part due to increased groundwater pumping to support agricultural production. Between 2011 and 2014, the combined river basins have lost 4 trillion gallons (15 cubic kilometers, or 12 million acre-feet) of water each year, an amount far greater than California's 38 million residents use in cities and homes annually. AFP PHOTO / HANDOUT / NASA / JPL-CaltechHO/AFP/Getty Images

Moving agriculture to higher latitudes may improve access to water. But the further up you go, the less light you get. Hence the grow lights.

"That's how you get tomatoes grown in Canada in the wintertime, because there's not enough light there," said Kevin Wells, chief executive of the grow light manufacturer Lumigrow.

A basic Lumigrow lamp starts at $600. More advanced models sell for $1,000 or more. Commercial greenhouses may use hundreds of thousands of these LED lights, said Wells. The company recently supplied the U.S. Department of Agriculture with a number of grow lights in a bid to reduce carbon emissions and cut energy costs. Its other clients include the likes of Bayer, which has a sizable agriculture division. Next year, the company anticipates doing $20 million in sales.

Even as farmers look to move some crops indoors to extend the growing season and adapt to a changing climate, others hope to coax more water from unconventional sources, such as clouds. Cloud seeding — the firing of silver iodide into the cloud layer to stimulate precipitation — typically relies on ground-based launchers or manned aircraft to distribute the chemical. But with the rise of unmanned aerial systems, researchers dream doing cloud seeding cheaply and easily — with drones.

Scientists in Nevada are currently evaluating such systems in the state's federally approved testing site. It's not clear when they might start flying; the Federal Aviation Administration only recently began offering exemptions to its commercial drone ban on a case-by-case basis. But the agricultural industry isn't sitting still; already, a handful of drone operators have petitioned the government for agricultural exemptions. And large agricultural associations, such as the American Farm Bureau and the National Agricultural Aviation Association, have also lobbied Congress on the matter of unmanned systems.

As much as drones and grow lights might help the industry adapt to a changing climate, the technology's also a reminder of climate change's unequal effects. For American growers, the decision to start seeding clouds with a drone may be easy — and cheap. For farmers in other parts of the world, it's probably a different story.