“All the grapes were ripening at once," Wendy Cameron recalls of the harvest that was the wake-up call.

Cameron is head winemaker at Brown Brothers, one of Australia's largest and oldest wine producers. In her 16 years there, Cameron had seen changes — hotter summers, harvest dates inching earlier. While heat waves aren’t unheard of in Australia, the one they had during the late summer of 2008 was unlike anything she’d ever seen: It was over 105 degrees for 10 days straight.

You can’t just leave ripe grapes on the vine — their sugars will get too high, yielding wines that are too alcoholic. Too much sun exposure can also affect flavor, and eventually grapes will begin to raisin. Everything had to be harvested at once, Cameron knew, but they only had so many employees. The winery was designed to handle a limited amount of production at a time. They didn’t have enough refrigerators. They didn't have enough water. (Water prices had tripled over the past year.) Those were taxing, frightening days, and Cameron says they got through it pretty well, all things considered. But it made her wonder about the future of Australian wine and whether the vineyards would remain cool enough to survive.

Two years later, in 2010, Brown Brothers' chief executive Ross Brown announced the purchase of a large vineyard in Tasmania, an island 150 miles off the southern coast of Australia. Long thought to be too cold to make quality wine, that too had been changing in recent years. “'We want to position ourselves to combat global warming,” Brown said at the time of the sale, a statement that garnered headlines — and upset many.

“I know Ross got some calls that were utterly scathing,” Cameron says. Others, especially others in the wine business who’d likewise seen the writing on the wall, praised his candor, albeit quietly. “People said, ‘Wow. I can’t believe you’ve done that, it’s so progressive and forward and good on you.’”

“Climate change isn’t a straight line,” Cameron says. “It goes up and down. There were a couple of years there where, certainly as an industry, we had a bit of a taste of what it might be like. The Brown Brothers have just celebrated their 125-year anniversary. My job is to give them the right information so we can be viable in another 125 years.”

The question is how difficult a task that will be, not only in Australia and other hotter wine-producing regions, like southern Italy, Spain, and California's Central Valley, but throughout the wine world. A splashy, controversial study published last year by the Proceedings of the National Academy of Sciences found that in major wine-producing regions, the area suitable for viticulture — wine-grape growing — is threatened. By 2050, such terrain will decrease by between 19% and 62%, under a business-as-usual carbon emissions scenario, and between 25% and 73% if carbon emissions increase, which some argue is more likely. The U.S. government's 2014 National Climate Assessment, which lays out in spectacular detail and no uncertain terms what our country should anticipate in terms of climate change, summarizes American wine's situation thusly: "The area capable of consistently producing grapes required for the highest quality wines is projected to decline by more than 50% by late this century."

The story of how wine will react to climate change is one small but telling piece of the larger one of how agriculture as a whole will endure. But researchers are looking at wine specifically because for this slow-moving, climate-sensitive industry, anticipating how to properly adapt will be a particular challenge.

You can’t just move Napa or Bordeaux a few hundred miles north. Even a small change in overall temperature, or increased instances of extreme weather, will throw wrenches into the hard-won understanding producers have of their grapes, land, and climate — and of how to coax from that combination the best possible beverage. It's not all bad news: A changing climate means that colder regions like Tasmania — and England, Scandinavia, and British Columbia — now have shots at becoming major wine players like never before. Will these new wine regions actually be able to replace the ones that have been cultivated for decades and in some cases centuries? Or will fine wine be something we lose to climate change?