Global warming is going to have profound effects on human life, almost certainly in ways that we cannot anticipate. This is especially true of agriculture, which relies so much on climate, and that applies doubly to a crop like the grapes that make wine. Sandra Allen looks at how vintners are trying to adjust.
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?…On a map, the world’s wine regions are particular little bands that fall in between the 30th and 50th parallels, the majority in highly biodiverse Mediterranean climates. This is because, as crops go, quality wine grape vines are super finicky. They need a cold — but not too cold — winter. They need a mostly frost-free spring during which their buds can safely emerge. They need a long, sunny growing season and eventual temperatures that are fairly warm — but not so hot that the grapes will sunburn or ripen too quickly. They need a fluctuation between daytime and nighttime temperatures, which enable the development of compounds that eventually become the complex flavors in a fine wine. Wine grapes are prima donnas; you don’t give them exactly what they demand, they don’t perform.
Complicating things further, there are many different kinds of wine grapes, called varietals, like chardonnay, merlot, or riesling, which are even more particular about where and under which conditions they’ll best grow. Go over a certain threshold of temperature? You can’t grow pinot noir. Go under? You can’t ripen cabernet sauvignon.
This fussiness also makes wine grapes especially useful for gathering data about weather: Each vine is like a remote sensor out in a field, and the behavior of wines across a region can paint a picture as to a given season’s weather. European vintners have been keeping records for about a thousand years, which is one way climatologists have learned about Europe’s historical climate, including the Little Ice Age that struck the continent between 200 and 700 years ago.
The result, almost certainly: higher prices. You might want to stock up now.