Saturday, October 19, 2019

Climate change and agriculture - a case of wine

Why, you may ask, am I troubling you about wine production. Think of climate change effects on what wines are produced, when and where, as a harbinger of global change.

Eric Asimov, The Times’s wine critic, describes How climate change impacts wine. More generally, Climate change will inevitably transform the way the world produces goods.

… more disruptions are coming, much faster than anybody expected. The accelerating effects of climate change are forcing the wine industry, especially those who see wine as an agricultural product rather than an industrial beverage, to take decisive steps to counter or adapt to the shifts.

So far, these efforts are focused on five factors that are inherently crucial to growing and producing wine.

(1) The Wine Map Is Expanding

For some of the world’s best-known grapes, including pinot noir, chardonnay, nebbiolo and riesling, these borderline environments permit a combination of low yields and phenolic ripeness, in which sugar, acid and tannins are in balance for producing thrilling wine.

Conversely, if these grapes are planted in overly fertile soils in warm climates, the wines they make will seem dull and flabby, with little of the character and nuance that has made them so prized.

As the climate has warmed, regions that were once considered too cold are now demonstrating that they, too, can produce fine wine, as long as the other elements are in order. In pursuit of the best sites, wine producers are moving north in the Northern Hemisphere, and south in the Southern.

England is a perfect example. Thirty years ago, nobody had ever heard of English sparkling wine. But as the climate has warmed, a world-class sparkling wine industry has developed, with new vineyards being planted at a dizzying pace, primarily along the southern coast.

(2) Winemakers Are Seeking Higher Ground

Today, vineyards in the regions of Salta and Jujuy in northern Argentina are at altitudes of 5,000 to 11,000 feet, among the highest vineyards in the world. In the Walla Walla Valley of Washington State, growers are experimenting at 3,000 feet, higher than ever in the region.

Some long-established vineyard areas, once not well regarded because of their relatively high altitudes, are also looking better because of climate change.

(3) Growers Are Curtailing Sunlight

For centuries, a formula governed the placement of some of the world’s greatest vineyards in the Northern Hemisphere. They would be planted on hillsides, with suitable soils, facing south or southeast, where they would receive the most sun and warmth, allowing grapes to fully ripen. … As areas in the Southern Hemisphere were planted with grapes, the reverse was true: North-facing slopes were most in demand.

[For example:] In the Yarra Valley of Australia, growers are rethinking the conventional wisdom of seeking north-facing vineyards. Mac Forbes, an exceptional grower and winemaker, signed a lease in 2017 for about 10 acres facing south. There, in Don Valley, he planted chenin blanc, pinot noir and nebbiolo, all of which benefit from a relatively cool climate.

(4) Regions Are Considering Different Grapes

For many producers, particularly small family estates or those in historic appellations, new vineyards in cooler environments are not an option. Instead, they must consider whether to change the essence of what they have been doing, in some cases for centuries.

That might mean leaving behind the grapes that have long been associated with their region, and selecting ones more appropriate for the changing climate.

It may seem impossible to imagine Bordeaux without cabernet sauvignon and merlot, or Champagne without pinot noir and chardonnay, but the prospect of a much warmer future may require even the most famous wine regions to rethink their methods.

This is already happening experimentally in Bordeaux and Napa Valley, two prestigious regions closely associated with cabernet sauvignon. In Bordeaux, where producers may use only grapes that are permitted by the appellation authorities, seven additional grapes have been selected for experiments to determine whether they can be used to mitigate the effects of climate change.

(5) Weather Is No Longer As Predictable

For farmers, and especially grape growers, experience counts for an awful lot. No two years are identical, but over time they will have seen many different weather events and learned how to respond in most cases. Meticulous records over decades, even centuries, can be a big help.

While weather always surprises, experienced farmers generally knew what to expect. With climate change, that is no longer true.

In California and Australia, where access to enough water can no longer be taken for granted, growers must consider either grafting their familiar grapevines onto drought-resistant rootstocks, or selecting other grape varieties.

Drought goes hand in hand with forest fires, or bush fires, as they are called in Australia. Institutions there have led the way in researching how smoke from fires can taint grapes and wine, and in finding technological solutions that will at least render such wines drinkable.

Viticulture by its nature is complicated. As the world’s climates are transformed, it is only becoming more so.

This is the first of a four-part series on winemaking and climate change.

No comments:

Post a Comment