Coffee snobs may be accused of being picky about their java, but coffee itself is even picker. The coffea arabica tree, the species that produces 70 percent of the world’s coffee, likes to be at between 64 and 70 degrees Fahrenheit, a range usually found in the highlands of equator-hugging countries like Brazil and Indonesia. Once the annual mean temperature goes above 73 degrees, the plants become stunted and degraded. So coffee is already being hit hard by climate change, with growers from Tanzania to Guatemala seeing declines in their crops due to higher temperatures, unusual rains and an increase in pests such as coffee berry borers, who thrive in warmer conditions. Ultimately, climate change is expected to reduce the current coffee growing regions of the world by half.  

Which is why it may be surprising to hear that coffee is now growing in Southern California. Once thought impossible, growers are now producing well-rated beans. This too is due, in part, to climate change. Farmers are growing the coffee plants in the shade of their avocado trees, which need ample water to produce abundant fruit. Water is more expensive. Water is more expensive because of the drought that has plagued California for much of the past five years. One of the forces behind the drought is climate change.

These kinds of moving puzzle pieces—avocados go out in California, coffee goes out in the tropics, coffee comes in to old avocado plantations—are likely to become more common as climate change ramps up over the next 50 years. While right now California coffee is a luxury novelty, it represents something larger. By looking at phenomena like California coffee, we can begin to see how farmers globally will need to begin innovating in the face of changing weather.

“You don’t see a lot of systemic change at this stage, but it’s coming,” says Paul Gepts, a professor of plant sciences at the University of California at Davis.

How much farmers will be affected will depend on how much the climate warms, Gepts says. If we stay within 1 to 2 degrees Celsius of current global averages, most farmers will likely be able to grow the same crops by changing their cultivation practices. But if global averages rise 3, 4 or 5 degrees, as many models predict, farmers will have to shift to entirely new crops.

We’re already seeing many American farmers change their cultivation practices in the face of climate change, Gepts says. In California’s Central Valley, farmers are increasing the use of drip irrigation, which decreases the amount of water needed for a crop. Drip irrigation, which requires costly equipment, was originally used mostly for water-intensive crops like fruit trees, nuts and vegetables. But now it's used in field crops as well. Hops growers in Washington are doing the same, hoping to save their threatened crop, a crucial component in beer.

In the Midwest, farmers are also changing their cultivation practices to deal with shifting weather. In Iowa, changes in thunderstorm patterns mean the ground is staying wetter for longer. But if newly planted seeds are in wet ground too long, they will die. So farmers are innovating, putting in drains, using bigger, faster farm machinery to put seeds in more quickly to take advantage of good weather while it lasts, and coating seeds in fungicides to keep them from rotting. Many of these innovations were developed independent of climate change concerns, but they’re helping farmers deal with their new conditions.

“The reason why climate change hasn’t affected farmers in the Midwest as much is in part because of this innovation,” says Gerald Nelson, a professor emeritus of agricultural and consumer economics at the University of Illinois at Urbana-Champaign.

Small farmers, who grow most of the crops in the developing world, will have a harder time innovating, Nelson says, as they don’t have the money or the clout that large farms do. But some developing countries, including India and China, are now putting more money into agriculture and consolidating their small farms into larger ones, which may make a difference.

Next, farmers may begin switching to relatives of their current crops. If you grow a cool-weather legume like peas or lentils, you could switch to a warm-weather one like black-eyed peas. Only when this is no longer sufficient will farmers begin to switch crops entirely.

“And that in itself is not as easy as it sounds, because you have a whole infrastructure geared towards a crop,” Gepts says. “The harvest equipment, the transport equipment and so on.”

But, Gepts says, that's not stopping farmers from trying. “You can also see that the crops are going to move northwards in the Northern Hemisphere or southwards in the Southern Hemisphere,” Gepts says. “So what’s now grown in California might be grown even further north, even in Canada.”

This is already starting to happen in some places, with rice cultivation shifting northward and fruits like peaches and grapes being grown in southern Canada.

And at some point, simply shifting where crops are grown no longer works. “There are some places you can move, but all these places have their own issues,” Nelson says. “You can move into Canada, but you’ve got this big rocky thing [the Canadian Shield, an exposed portion of the continental crust that makes up 50 percent of the country’s landmass] that makes it hard to grow crops. You can go north into northern Germany or Sweden, but you’re going to have to cut down forests, and that’s got its own contribution to climate change. In Northern Russia, there’s a lot of peat, and [draining peat bogs] puts CO2 into the air.”

As for the world’s coffee growers, 70 percent of whom are small farmers, a few have found a new crop already. In Nicaragua, where temperatures have risen as much as 3 degrees Celsius in the past century and coffee crops were recently devastated by a coffee leaf disease called roya, some are turning to cocoa. In 2015, cocoa exports were up 80 percent from the previous year. In neighboring El Salvador, an international partnership aims to dramatically increase cocoa production as well. And in Honduras, the government has mandated that growers devote 8 percent of their coffee land to cocoa.

“Coffee is no longer viable due to climate change,” said one former coffee farmer who has turned to cocoa, quoted in Reuters.

This could help offset a small bit of the losses from the world’s current largest cocoa producing region, West Africa, which is facing drastic cocoa crop reductions due to—you guessed it—climate change. Here, temperatures are expected to rise 2.1 degrees Celsius by 2050, driving the optimal cocoa-producing altitude upward by anywhere from 350 to 1600 feet. Growers can begin to move up into the mountains, or they can try other strategies, including replanting rainforest trees to provide shade and cool to their cocoa crops. This would have the added benefit of adding more carbon dioxide-sucking trees to the world.

Clearly, what we really need is a stronger global effort to halt climate change. But unless that happens, we’ll almost certainly be seeing more coffee in California and peaches in Canada. And then, perhaps sooner than we think, we'll have none at all.