UK viticulture has been described as a sector that benefits from climate change. As we enter English and Welsh Wine Week 2019, there is a lot of excitement surrounding the sector, especially after last year's 'harvest of the century'. But Kate Gannon says the UK's fast-growing wine sector must take into account the risks, as well as the opportunities, from climate change.
Viticulture in the United Kingdom: a rapidly expanding sector
Climate change is changing the landscape of global wine production, and UK viticulture is a rare sector in which global warming trends present both an opportunity and a challenge.
Often described as the “canary in the coal mine” of global agriculture, wine grapes are exceptionally sensitive to climate and only grow at their best within narrow climate ranges – typically between 13 and 21°C. Warmer climates have brought a greater area of the UK within the ideal climate range for a number of commercially popular wine grape varieties, including several wine varieties that have defined some of France's finest wine regions. In fact, Chardonnay and Pinot Noir grapes, two of the primary varieties used in Champagne production, have dominated modern production in the UK and accounted for 61.7 percent of new vineyards in 2017.
A lot of excitement surrounds the sector. It is growing rapidly, as demand outstrips supply. Vineyards now cover about 2,500 hectares, an increase of 246 percent over 2004 levels. WineGB, the national association of wine growers and producers, has predicted that the UK industry will sell 40 million bottles a year by 2040. English sparkling wine, which accounted for 68 per cent of UK wine production in 2017, has gained international recognition, winning a number of prestigious international awards for its distinctive bright, fresh, cool-climate acidity. Alongside French Champagne producers acquiring cultivation sites on UK soil (Tainter in Kent and Franken-Pommery in Hampshire), a number of notable British brands have emerged, including from Nitember, Camel Valley, Ridgeview and Chapel Down Estates.
Last year was described as the “harvest of the century”, as favorable weather conditions led many farmers to report unprecedented harvests. Commentators were particularly enthusiastic because this highly robust species may have enabled producers to build up reserves for less abundant years, to support reliable supplies and expand the sector's development.
Climate-related advantages over Old and New World producers
Besides rising growing season temperatures, there are other reasons why UK viticulture is optimistic, especially when compared to many of the world's more established wine-growing regions.
The cool climate gives the grapes more time to ripen
Firstly, cooler climates such as those in the UK allow for a longer ripening period, giving the fruit time to ripen complexly and deeply. In fact, grapes grown in areas close to the border where they can successfully ripen are known to produce some of the most interesting wines. In contrast, the distinctive tastes of some classic wine regions are thought to be threatened not only by increasing climate extremes, changing crop disease profiles and increased risks of fires, droughts, floods and storms, but also by warmer temperatures that advance the timing of the wine season. Stages of grape development.
Many of the world's major traditional wine regions are located in regions that experience average growing season temperatures that already exceed optimal levels for the grape varieties for which they are famous. In California's Napa Valley, for example, high growing season temperatures often force early harvesting, to maintain acidity levels that support wine quality and aging potential, or to control alcohol concentrations. Even subtle changes in the length of the growing season or alcohol content can have consequences on a wine's depth, balance and distinctive expression.
Freedom to define tastes
Second, while viticultural tastes and regions – determined by the environmental factors that shape winemaking – are always evolving, UK producers remain relatively unconstrained by the current paradigms that define their more established counterparts and historical roots on mainland Europe. Wine production, especially in Old World viticulture, is intertwined with deep connections to place and cultural heritage, limiting growers' ability to adapt production to changing climatic conditions. Brands and territories are often built around traditional soils, topographies and variety pairs, which, along with associated styles, have been embodied in protected geographical appellations and appellations of origin.
The wine-growing identity of a region is often determined by one or a very small number of varieties – consider, for example, the importance of the Sangiovese grape to the wines of Chianti and Brunello di Montalcino in Tuscany. Fine wine producers, in particular, often trade their wines as an ancestral art spanning generations, with a brand that hinges on a distinct, distinct region and geographic location. These brands may not be easily reconciled with changing the base variety to one with traits more adapted to a changing climate, or with moving vineyards to higher altitudes or latitudes in response to changing climatic conditions. In contrast, UK producers operating within a younger, less established production scene arguably have greater freedom to define the tastes and styles of their wines to maximize the current – and future – opportunities presented by the changing climate.
More control, than using chaptalization
Third, as long as latitude provided adequate protection for the grapes from conditions associated with extreme heat or sunburn, English and Welsh winemakers might begin to have greater flexibility and control over the alcohol levels and flavors of their wines than their European counterparts, through the use of chaptalization. This process involves adding sugar before fermenting the grapes to enhance and control the alcoholic content of the wine. Bifurcation has been common in many cold regions. However, some European producers have discontinued this practice as a result of higher natural sugar levels in their grapes as a result of hotter growing seasons. This means, in some ways, that these producers have lost a degree of control over their production process. Meanwhile, baptism remains popular in the United Kingdom.
Less pressure on water resources
Finally, as warming climates contribute to an increased need for irrigation among more and more vineyards planted globally, almost no UK producer currently irrigate their land. In the changing climate, the viability of dry farming in UK viticulture may be greater than in other, older wine growing regions. This is important given the enormous water footprint of irrigated viticulture: a footprint that has prompted climate change and viticulture commentator Linda Johnson Bell to argue that in an increasingly water-scarce world, climate justice requires that dry farming become the new standard of sustainability. For this inevitable “luxury” crop.
Building future climate resilience in UK viticulture now
Despite these opportunities for the English and Welsh wine sector, production is likely to remain unstable and subject to increasing climate risk fluctuations as a result of climate change. Like the rest of the world, the UK is experiencing and expecting more extreme events and greater fluctuations in weather and climate than before. Strong 2018 UK results highlighted that along the margins of viticultural suitability, deviations from “normal” growing conditions can produce opportunities. However, extremes arising from human-induced climate change are also likely to regularly exceed those that allow UK vines to produce their optimum fruit. From threats such as increased risk of frost (caused by earlier bud burst leaving vines vulnerable to spring frosts), to disturbed growing seasons, erratic production and frequent high losses are likely.
Lessons should be learned from the many modern commercial vineyards in the Old and New World that suffer from increasing climate vulnerabilities as a result of failure to take climate change into account in planting decisions: for example by increasing planting of more commercially popular, but less adapted, less hot and drier vines – Disease-resistant varieties such as Tempranillo. Instead, UK producers should take climate change adaptation into account in the design and development of the sector as it grows, choosing the best sites and soils for planting, and pairing them with suitable grape varieties. It takes at least three years for a new vine to produce fruit, dry-planted vines often take much longer to start producing, and fine wines are often produced from vines that are many decades old. This highlights the importance of making informed decisions in the long term. With investment rising and more land coming into production all the time, these are the decisions the UK viticulture sector needs to make now.
The CREWS-UK (Climate Resilience in the UK Wine Sector) project supports climate change adaptation decision-making to build resilience within the sector. Over the next year, our research team will leverage the launch of the new UK Met Office Climate Outlook (UKCP18) to analyze how climate trends and variability will impact the UK wine production sector and identify pathways to support long-term economic sustainability. CREWS-UK is a partnership between climate scientists, wine sector professionals and social scientists from the Grantham Research Institute, the University of East Anglia, Weatherquest and Vinescapes. This work is supported by the UK SPF Research and Innovation Program on Climate Resilience (grant reference number NE/S016848/1). Read more about this project here.
The author would like to thank Alastair Nesbitt (Vinescapes) and Steve Dorling (Weatherquest) for contributing ideas to this commentary. Any inaccuracies remain the author's own.
