How Climate Changes will Change the Wine Climate
How would you feel about uncorking a Grenache from Gevrey-Chambertain or Marsanne from Meursault? Or would you rather start the evening with a Swedish sparkling wine? Global warming is expected to do quite a number on the agricultural regions of the world in the coming decades, and what is wine if not an agricultural product? Possibly even the most sensitive agricultural product we have. The first climate changes are already here and our winemakers know...
For classic wine areas such as Burgundy, records dating back to 1354 give us insight to what is already happening. Only in extreme heat years, such as the “almost unbearable” year 1540, were harvest dates as early as they have been every year in the past 30. Records kept by monks and other wine growers show us temperature records for 700 years.
It turns out, temperatures have moved up and down a bit every year but have hovered around a constant. This track record is now broken, and eight of the earliest harvest dates on record have taken place in the past 16 years (https://www.nationalgeographic.com/science/article/wine-harvest-dates-earlier-climate-change).
In 2020, an international research team published a study (https://www.pnas.org/content/117/6/2864) which showed that a two degree C global warming would make 56% of current vineyard areas unsuitable for wine growing. Those two degrees are the limit at which irreparable damage will be done to the world’s ecosystems - a limit which we are approaching fast in spite of the Paris agreement. The Intergovernmental Panel of Climate Change, IPCC, says it is likely to happen this century.
Wine grape cultivar diversity can impact the loss of current wine growing regions. Assumptions of loss are shown for scenarios of 2 °C warming (yellow) and 4 °C warming (red) relative to a 0 °C reference scenario.(Figure by PNAS.)
Though a few new cool climates, such as Sweden, Denmark or even England, might benefit from climate change in a viticultural sense, most of the world’s famous areas under vine will not. Countries that are already warm, like Spain and Italy, are expected to lose up to 90% of their wine growing regions. Bye bye Barolo, so long Sagrantino.
Four degree temperature increase? You don’t even want to think about it and neither do I. At that point, the loss of 85% of the world’s wine growing regions is unlikely to be our biggest problem. Our children or grandchildren might drown their sorrows from the state of the world in the very rare, highly alcoholic and very tannic wines that would still remain.
So what happens to the world of wine when the climate changes? And is there a way to mitigate the negative effects?
Though we might think mainly of changes in temperature riper grapes, the main challenge for wine growers in a changing climate might be access to water. Areas receiving little rainfall will likely get less and watering might get prohibitively expensive. In many regions, switching to dry farmed vines or letting rootstocks create deeper roots is already a good idea which can also bring interesting quality improvements.
Terroir as we currently recognize it is bound to change. The New World wine regions unbound by the strict regulations of European appellation rules, can be quicker and more flexible in changing the most common grape varietals of a region to suit the new climate. According to researchers, this is a way to save at least some of our wine growing regions. (https://www.pnas.org/content/117/6/2864)
The main challenge for wine growers in a changing climate might be access to water. Areas receiving little rainfall will likely get less and watering might get prohibitively expensive. (Photo by alohamalakhov from Pixabay)
But not only laws stand in the way in classic appellations. Even if it were permitted: imagine a Burgundian wine grower in charge of a small parcel of Grand Cru vineyard where his (or her) family has grown Pinot Noir for five generations. There would be a cultural challenge to changing those vines over to Gamay and a cost in tearing them out or re-grafting. Will the consumer really be interested in paying a premium for Cote d’Or Gamay?
That sooty flavor can’t be washed away and can even affect wine resting in the barrel. Very low levels of smoke taint do to a wine what a well toasted barrel does and isn’t necessarily a problem. Rosé wine has much less skin contact than red wine and can be a way to save some lightly tainted red grapes. But if more soot is deposited on the grapes or leaves? Forget it. One Sonoma producer I spoke to said he had full use of his grapes only two years out of the last five because of smoke taint.
California had massive burns the last years. However, 2020 was even a record-setting year of wildfires in California, according to the California Department of Forestry and Fire Protection. By the end of the year, 9,639 fires had burned 4,397,809 acres, which is more than 4% of the state's approximately 100 million acres of land. Photo by Erin Donalson
In addition to droughts, wildfires and too much heat causing overripe grapes, there are the risks of frost after bud break, hailstorms, new pests and flooding. These events are already causing European vintners headaches and grief. But everything isn’t hopeless. Scientists have looked at where the top grape varieties would be better suited in the case of a 2 degree change.
Colder climates, such as Germany or Oregon, will fare better and many areas that currently require luck or hybrid grapes, such as Scandinavia, are likely to improve their quality significantly. Maybe our best Pinots will come from Southern Sweden in 15 years, with the world’s top sparkling coming from the calciferous soils of the Baltic sea island of Gotland. At 4 degrees of global warming, we will be able to add 5-8% of new wine regions where it is currently too cold for even the hardiest grapes.
For the rest of the world, winemakers will need to get the balance right between ripening flavors and rising alcohols. Chaptalisation (addition of sugar) in the areas of the world where this is permitted is likely to be a thing of the past.
Strong sunlight leads to tougher skins with more tannins so the winemaking process might need to focus more on softening these tannins or shortening the time the tannins are extracted with skin in contact with the juice at fermentation. To protect the grapes from excess sun, we might see changes in how the vineyards are managed. Especially with higher trellising, shade cloth and more dense canopy management, keeping grapes further from warm soil and more protected with greater amount of foliage.
Nevertheless, changing the grape varieties is a way to significantly reduce the loss of area under vine in case we are not able to reverse the current increase in temperature: (https://news.climate.columbia.edu/2020/01/27/wine-regions-shrink-climate-change/).
For the classic favorites, this could mean Burgundy grapes in Northern Europe, Bordeaux grapes in Burgundy, Rhone varietals in Bordeaux, and so on. Are we as consumers ready for this? I don’t know. Personally I’d rather like do all I can to keep the scenario from happening in the first place. When it comes to my wines, that means purchasing sustainable, dry-farmed wines in light weight bottles.
Learning about the climate mitigating practices of the winemakers and wineries. Asking some hard questions and passing on prestige wines in massively heavy glass bottles. If it does not work? Pour me a glass of the Côtes du Iceland, please.