On a misty autumn morning in Sonoma County, California, Katie Jackson headed into the vineyards to assess the harvest. It was late in the season, and an army of field workers was rushing to pick the grapes before the first rains, however faint, began falling.

But on this day, Jackson, vice president of sustainability and external affairs at Jackson Family Wines, was not just minding the usual haul of cabernet, chardonnay and merlot grapes. She also checked on the sophisticated network of systems she had put in place to help crops adapt to a changing climate.

Jackson, along with her siblings and mother, owns and operates Jackson Family Wines, one of the largest family-owned winemakers in the country. Best known for its Kendall-Jackson chardonnay, a supermarket staple, the family also produces dozens of other wines on five continents. After decades in the business, the Jacksons are sensitive to slight variations in the weather, and they are convinced of one thing: It is getting hotter and drier, and that could be a problem.

As California endures a yearslong drought, the Jacksons, like other winemakers, are grappling with new realities. Grapes, though a surprisingly resilient crop, are ripening earlier. Nights are warmer. Aquifers are running dry.

As a result, the region’s wine country has become a laboratory for the reshaping of agriculture nationwide. Because, of course, it’s not just California that’s warming up.

The Jacksons are going beyond the usual drought-mitigation measures. They are using owls and falcons to go after pests drawn by the milder winters. They are finding new ways to capture rainfall. And since fossil-fuel consumption is one of the biggest drivers of climate change, they are trying to become more energy efficient, in part through the use of old-school farming techniques.

Learning, ‘little by little’

Climate change is forcing the Jacksons to confront questions both practical and existential: Can you make fine wine with less water? Will good grapes still grow here in 20 years? What will become of an industry central to California’s identity, one that says it contributes $114 billion per year to the nation’s economy?

Wearing jeans, a plaid shirt and hiking boots, her hair pulled back in a loose ponytail, Jackson, 30, caught a ride with one of the vineyard managers to a hill overlooking the picturesque Alexander Valley, an area that produces some of California’s best wines.

At the peak, she stopped to inspect a shed housing the recently updated belly of the vineyard’s irrigation system. Inside was a new energy-saving variable-frequency drive that allows for more precise, efficient watering.

Nearby was a solar-powered weather station. If the sensors decide it has become too cold in the middle of the night (climate change, of course, doesn’t mean it’s always hot), new wind machines will automatically start circulating warm air to protect the vines.

Beside that was an owl box — occupied — part of an effort to control pests without pesticides. And just below the peak was a man-made reservoir, one of more than 100 added to manage what is any farm’s most precious resource: water.

“The climate has been getting warmer and warmer, and we’re seeing more extremes, from really wet to really dry,” Jackson said. “Little by little, we’re learning.”

So far the drought has not wreaked havoc on the California wine business. No harvests have been destroyed and quality remains strong. Moreover, many of the Jackson vineyards are in pockets of the California coast that benefit from the cool, humid fog.

But the challenges are hardly theoretical. Climate change is threatening the world’s coffee supply. Several reports suggest that rising temperatures around the globe could imperil major winemaking regions in the coming decades. One study suggested that by 2050, many regions in Europe, including much of Italy and swaths of Southern France, could become unsuitable for wine grapes. The same study suggested that California production could fall by 70 percent by the century’s midpoint.

Winemakers in the region are noticing distinct changes that signal a hotter, drier future.

“It used to be there were a lot of nights when it would get 28 and 29 degrees, but now when farmers wake up, they’re less likely to have a mud puddle with ice on it,” said Daniel Sumner, a professor of agricultural and resource economics at the University of California, Davis. “The growers are going have to be a little bit more nimble.”

‘Data-driven farming’

Climate change wasn’t a pressing concern for Jess Jackson, a San Francisco lawyer, when he bought an 80-acre pear and walnut orchard in Northern California in 1974. Jackson wanted to try his hand at winemaking, and planted grapes on the land.

About a decade later, he released the first vintage of Kendall-Jackson. Aged in French oak barrels — a rarity for an American wine — Kendall-Jackson was an instant hit. Jackson was soon acquiring more vineyards throughout California.

Jackson, who died in 2011, raised his children around the business. Katie Jackson worked her first harvest cleaning tanks and filters in a cellar. Today, she leads the company’s sustainability efforts, pushing for the use of less water, lower fossil-fuel consumption and more natural farming techniques.

In 2008, the company formalized its sustainability program and began measuring its energy and water usage and its greenhouse gas emissions. “They are leaders,” said Rex Stults, government relations director of Napa Valley Vintners, a trade group. “But this is becoming an important topic for just about everybody.”

The clearest sign of the Jackson family’s efforts can be found in the network of more than 100 reservoirs scattered across its vineyards. Some have cost as much as $1.5 million to build.

The Jacksons have also begun analyzing their crops with increasingly sensitive tools. Jackson recently installed devices that measure how much sap is in the vines. They transmit the data over cellular networks to headquarters, where software calculates how much water specific areas of vineyards do or don’t need. “Data-driven farming,” Jackson said.

The Jacksons are also monitoring their crops using drones equipped with sensors that detect moisture by evaluating the colors of vegetation. The wrong color can indicate nutritional deficiencies in the crops, or irrigation leaks.

“Previously, it would require an experienced winemaker to go and look at the grapes,” said Clint Fereday, the company’s director of aviation. “Now we can run a drone, tag an area of the vines with GPS, and go right to the spot that has a problem.”

Jackson’s husband, Shaun Kajiwara, is a vineyard manager for the company, overseeing the grapes that go into many of the upscale labels. Walking through rows of vines that will yield $100 bottles of wine, he said that in recent years the company has begun planting new vines that send roots deeper into the soil, drawing more ground water and requiring less irrigation.

The company also began sanitizing the 51,000-gallon tanks it uses to blend chardonnay with ultraviolet light instead of water. There is an elaborate new rainfall capture system. And workers have devised a system to recycle the water used to wash barrels. In total, these efforts are saving 28 million gallons each year in the company’s California wineries.

“Each year we’re finding more and more ways to make use of this water that was going down the drain,” said Sam Jamison, general manager of the label La Crema.

Now Jackson is overseeing an ambitious groundwater recharge project. This winter, the company plans to capture stormwater runoff and flood a large, flat vineyard near the La Crema winery. If all goes as planned, the water will seep down and help replenish an aquifer from which the farm draws.

All these efforts have put the Jacksons in an enviable position: They have more water than they need.

In 2015, Jackson learned that the Green Valley Creek, an important tributary for the Russian River, was in trouble. Once a healthy stream, the drought had shriveled it to a series of stagnant pools, only occasionally connected by flowing water, adding to problems for the coho salmon, an endangered species. The Jacksons grow pinot noir grapes on a hill near the creek, and maintain a reservoir there; Jackson offered to release water in a bid to help the fish. Soon PVC piping was rigged up to the reservoir, winding down 2 miles of hillside to the creek.

Pushing away overgrown branches, Jackson made her way to the creek’s edge, where she met up with David Hines, an in-stream flow specialist with the National Marine Fisheries Services.

“It doesn’t look like much, but this is an important tributary for coho,” Hines said. In an eddy no larger than a kiddie pool were three baby coho, a few inches long and not more than 7 months old.

“They’re the young of the year,” Hines said.

For Jackson, it was all of a piece with her efforts to ensure a healthy future for her family’s business. And the family’s efforts are making a difference. Since 2008, Jackson Family Wines has reduced its annual water use by 31 percent.

“My family knows we aren’t out of the drought yet,” Jackson said. “There’s still a lower snowpack. There’s less groundwater in the Central Valley.”