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Home , Old World wine, Viticulture

Gregory Jones

limate is a pervasive factor in near- ly all forms of — from C determining the geographical area MAKING IN A CHANGING in which a given can be grown, to influencing annual yields and the quality of the crop. With such strong ties to agri- culture, climate also influences cultural issues, such as economics, regional identi- ties, and migration and settlement. These connections are never more evident than with the growing of and the pro- duction of wine. A BRIEF HISTORY OF

The grapevine is one of the oldest cultivat- ed that, along with the process of making wine, has resulted in a rich geo- graphical and cultural history. The cultiva- tion of grapevines () predates written history. Archaeological findings in the Caucasian Mountains, near the town of in ancient Persia, indicate that viti- culture existed as far back as 3500 B.C. vinifera (the "wine- bearing" and one of about 60 species of the Vitis genus that is principally used for winemaking) was first domesticated in this region and soon spread to Assyria, Babylon and the Climatologist Gregory Jones uses GPS to fix shores of the Black Sea. The Assyrians the coordinates of a for further brought the art and knowledge of wine- analysis. Research is showing a correlation making to Palestine and Egypt, and from between changes in climate and wine grape there, the Phoenicians carried the vine and quality. its secrets around the Mediterranean and east toward Morocco and Portugal. The the trading of wine. After the 15th century, cific wine style and its quality characteris- and Romans learned the from viticulture once again spread throughout tics. the Phoenicians and proceeded to spread and enjoyed a renewed growth in Although it is debatable which their knowledge of wine throughout popularity. European explorers then car- component is most important — land- Europe. Ultimately, the Romans were ried the vine with them to their new scape, , climate or cultural practices — responsible for the first vineyard plantings colonies and helped establish the climate clearly determines whether a in most of today's renowned viticulture in regions that were well suit- region can adequately ripen the to regions in the Mediterranean Basin. They ed for cultivation. produce high quality . History has cultivated the grapevine in , the shown that wine-grape-growing regions French valleys of the Rhône, Marne and TERROIR AND CLIMATE developed when and where the climate was Seine rivers, in Germany along the most conducive. For example during the and rivers, and even in the British From this long history of development has medieval "Little Optimum" period (rough- Isles. come a distinct regionalization of both the ly A.D. 900 to 1300), temperatures were up During the Dark Ages, grape growing grape varieties grown and the wine styles to 1 degree Celsius warmer, allowing the declined throughout most of Europe. produced. This regionalization is intimate- planting of as far north as the Viticulture would have died out during ly tied to both the landscapes and coastal zones of the Baltic Sea and south- this period had it not been for the Christian of these areas and has become synonymous ern England. Conversely, temperature monks who preserved the methods of viti- with the French term terroir (see story, declines during the 14th century were dra- culture and made vast improvements in page 20). While not directly translatable matic, leading to the "" cellaring techniques. From the 10th into English, the term has come to embody (extending into the late 19th century), and through the 13th centuries, the monaster- both the physical environment and cultur- resulted in northern vineyards dying out ies controlled the growing of grapes and al interactions that together produce a spe- and growing seasons so short that -

24 Geotimes n August 2004 www.geotimes.org ANGING CLIMATE

ing grapes in southern Europe was difficult. In general, the overall wine style that a region produces is a result of the baseline cli- mate, whereas climate variability determines quality differences. Today's viticul- tural regions for quality wine production are located in narrow climatic zones that put them at particular risk from both short-term climate variability and long-term climate change. Therefore, climatic changes have the potential to bring about changes in wine styles or regional viability altogether. Our understanding of climate change and the potential impacts on viticulture and vini- culture (the science of making wines) has become increasingly important as changing levels of gases and alterations in -surface characteristics bring about changes in Earth's radiation budget, global temperatures, atmospheric circulation and the hydrologic cycle. MEASURING THE IMPACT

In the wine world, it has become common- place to hear that the "(insert your favorite year) was the vintage of the century," as it has become increasingly easier to produce quality wines. Have these changes come about through better grape-growing prac- tices, better material, better winemak- ing techniques or more beneficial climates? While it is clear that advances in both viti- culture and viniculture have provided the tools to produce better wines, climate is the wild card that limits the geographical distri- bution of grape growing and determines and quality differences between years and regions. Although many have reasoned over the years that climate change may play an important role in wine quality, Janice Lough and colleagues in 1983 were among the first research groups to recognize the growing importance of climate change to the indus- try, in an article published in the Journal of Climate and Applied Meteorology. The authors showed that with warming climates, the growing seasons in Europe should lengthen, and that wine quality in and Bordeaux should increase. Today, we know that their results were large- ly correct, as the last 10 to 15 years have pro-

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WORLD VITICULTURE ZONES TOP 10 Top 10 wine producers in descending order 1. France 2. Italy 3. Spain 4. United States 5. Argentina 6. China 7. Australia 8. Germany 9. Portugal 10. South Africa

Top 10 wine consumers in descending order 1. France 2. Italy 3. United States 4. Germany 5. Spain 6. Argentina 7. China 8. United Kingdom The world’s major viticulture regions fall into bands of areas, with average tempera- 9. Russia tures between 10 and 20 degrees Celsius — giving a good spatial proxy for the limits 10. Romania of grape and wine production. The dots on the map represent the wine regions stud- ied in a global analysis by Gregory Jones and colleagues on the impacts of climate Top 10 wine consumers per capita in change on wine quality. descending order 1. Luxembourg 2. France vided a wonderful string of atures are a measure of the ripening poten- 3. Italy throughout much of Europe and the New tial for grape varieties grown in climates 4. Portugal World. that range from cool to hot. For example, 5. Croatia Numerous other studies suggest that cli- grapes are grown in regions 6. Switzerland mate change may impact grape growing that have mostly cool climates, with grow- 7. Spain and wine production. The potential ing-season temperatures that range from 8. Argentina impacts include changes in the geographi- roughly 14.00 to 16.00 degrees Celsius (for 9. cal distribution of viable grape-growing example, Champagne, and 10. Hungary (U.S. is 35th per capita) areas due to changes in temperature and Northern Oregon), while Cabernet precipitation, greater and disease pres- Sauvignon grapes are grown in regions Information from the Wine Institute sure due to milder winters, changes in sea that span from warm to hot climates, with level (which could potentially alter the growing season temperatures that range coastal zone influences on viticultural cli- from roughly 16.50 to 19.50 degrees mates), and the effect on vine growth and Celsius (for example, Bordeaux or Napa). grape quality from increases in carbon Our results show that from 1950 to 1999, dioxide. the majority of the world's high quality Until now, however, researchers had not wine- producing regions saw growing-sea- conducted a global analysis of the impacts son warming that averaged 1.26 degrees of climate change on wine quality. My col- Celsius. The warming has coincided with leagues and I set out to examine the a general increase in vintage ratings over observed changes seen in growing-season the last 20 to 40 years in these same temperatures and to link the variations to regions. Although the strength of the cli- trends in vintage ratings (a common meas- mate-ratings relationships varies by region, ure by which vintages are compared). a 1-degree-Celsius warming results in a Using a general circulation model for 27 of 13-point increase in the ratings on average arguably the world's finest wine regions, (on a 100-point scale). Cooler climate we were also able to project growing-sea- regions, such as the Mosel and Rhine son temperature changes. Valleys of Germany, appear to have gar- nered the most benefit. Currrent trends. Growing-season temper- At issue however, is that many of these

26 Geotimes n August 2004 www.geotimes.org ENGLAND'S WINE RENAISSANCE

he pop of corks may one day replace Tsoccer as the favorite cross-channel rivalry between France and England. English wines, particularly sparkling wines, are beginning to challenge France's dominance in the Champagne and wine market — a trend some scientists say is linked to climate change (see feature). In a blind taste test, recently conducted by Which? magazine in London, several English sparkling wines scored higher than the more popular (and pricey) French . Although English non- sparkling wines did not fare as well in the survey, a string of warm, dry summers and similar forecasts for the future has vineyard owners more optimistic than ever. "Last year was genuinely sensational, the regions are either at or nearing their opti- amount of sunshine and warmth have mum climates for the varieties grown and picked up in the last five years, and it's been wine styles produced. Wine-quality at least 15 years since something severe, impacts from climate change are evidenced like a late , has happened," says Frazer Thompson, managing director of mostly through more rapid plant growth English Wines Group, producers of Chapel Down . For winemak- and out-of-balance ripening profiles. A ers, better translates into a superior grape harvest with a more favorable ripening period that allows to accu- balance of sugars and acids. mulate, maintains acid levels and produces The conditions for viticulture have not been this good since the Medieval Warm the optimum flavor profile for that variety Phase, more than 700 years ago, says Richard Selley, a geologist at the Imperial will result in a balanced wine. In a warmer- College London. Following the warm phase, Europe plunged into the Little Ice than-ideal environment, the grapevine will Age and remained largely vineyard free until after World War II, Selley says. Since go through its phenological events (the then, grape production and quality have slowly increased throughout the world, combination of biological events with cli- which correlates to an increase in temperature over the last 50 years, reports mate) more rapidly, resulting in earlier Southern Oregon University's Gregory Jones and others in a presentation at the ripeness, and, while the grower or Geological Society of America's 2003 annual meeting in Seattle last fall. Today, is waiting for flavors to devel- there are close to 400 in England and Wales, with more likely on the way. op, the acidity is lost through respiration, In addition to increasing temperatures, the geology of southern England is resulting in "flabby" wines (high alcohol favorable to viticulture. "The geology of the British Isles is roughly comparable to with little acidity retained for freshness). In the European mainland," Selley says. "But what everyone is interested in is the addition, that occur in a warmer chalk, the Cretaceous limestone, because that is what Champagne is grown on." part of the growing season — for example, Selley adds that French Champagne growers have recently been buying up land in August or September instead of October in southern England that has this chalky soil. the Northern Hemisphere — will result in Despite the sunny outlook, Thompson maintains that not all English vineyards hot and potentially desiccated fruit without are hoping for global warming or even want to become a major wine-growing greater irrigation inputs. region. "Frankly, the world doesn't need another California , or anoth- er Australian red," he says. "What the world needs are more distinctive flavors, and Future trends. Examining future climates you can only get those from marginal areas." in the same wine regions, the research ana- If the warming trend continues, as Jones and his colleagues have predicted, lyzed output from a general circulation "marginal" may no longer apply to the English vineyards. in south- model from 1950 to 2049. A comparison of ern England have more than climate and geology to depend on though. "We're also two periods, 1950 to 1999 and 2000 to 2049, next door to London, with the highest concentration of Champagne drinkers in suggests that mean growing-season tem- the world," says Thompson, with a little British pride. peratures will warm by an average 1.24 Jay Chapman degrees Celsius over the wine regions stud- Geotimes summer intern ied. The magnitude of these mean grow- www.geotimes.org August 2004 n Geotimes 27 MAKING WINE IN A CHANGING CLIMATE

ing-season changes indicate potential shifts regions in Europe have stringent standards in the relationship between climate and by which varieties, yields, growing and wine varieties for many regions at or near a winemaking techniques, and wine styles are given threshold of ripening potential for regulated to assure quality and maintain varieties currently grown. identities. For example, the summer heat The projected changes are greater for the wave of 2003 in Europe produced very early Northern Hemisphere than the Southern harvests and some challenging growing Hemisphere. And the growing-season tem- conditions that without irrigation (largely peratures projected for 2000 to 2049 also outlawed in Europe) resulted in lower yields reveal significant changes in each wine and out-of-balance flavors. Although New region, with trends ranging from 0.18 World wine regions have fewer governmen- degrees Celsius to 0.58 degrees Celsius per tal constraints, growers and winemakers decade. Overall trends during the time peri- worldwide will need the freedom to adapt to od average more than 2 degrees Celsius the potential changes in climate in both the across all regions, with the smallest warming short- and long-terms. in South Africa and greatest warming in Perhaps a sign of things to come is being Portugal. seen across Britain, where the past decade or Our analysis reveals that the impacts of so has provided growing conditions not seen climate change are not likely to be uniform since the 13th century, and grapes have across all varieties and regions, but are more ripened and produced drinkable wine. In likely to be related to a climatic threshold the April 25, 2004, London Times, John whereby any continued warming would Walples and John Elliot report that a ven- push a region outside the ability to ripen ture between winemakers from Champagne varieties that are already established. Cooler in France and Kent and Sussex in England climate regions have a greater ability to will result in the first collaboration between adapt to climate change, as they would be the two regions. Perhaps the French have climatically more conducive to ripening seen one of the potential changes brought than some warmer climate varieties. If a about by climate change — shifts in viable region, however, is already in a hot climate areas — and are hedging their bets. This and warms beyond what is considered viable would appear to be the case in at least one for even the greatest heat-requiring vari- instance: A June 2, 2004, BBC story reports eties, then grape growing becomes challeng- that English sparkling wines either beat out ing and maybe even impossible. or equaled Champagnes in a recent taste test. LOOKING FORWARD While the exact magnitude and rate of climate change in the future is unknown, The observed warming of the past 50 years history has shown that climate and wine are appears to have mostly benefited the quality intricately linked. However, predicting of wine grown worldwide. However, the future wine quality is also inexact. The average predicted warming in the next 50 question may be whether wine lovers years has numerous potential impacts on the should buy a favorite wine from a favorite wine industry — including changes in region to hold onto, just in case, or whether grapevine phenological timing, disruption they should appreciate change and simply of balanced composition in grapes and wine, enjoy the potential range of new regions alterations in varieties grown and regional and new wines borne from a different cli- wine styles, and spatial changes in viable mate. grape-growing regions. Potentially even more important is that climate change, Jones is a climatologist and associate professor in the Geography Department at Southern through its direct impact on grape and wine Oregon University. He has published numerous production, has the ability to indirectly articles in the areas of climate variability and bring about cultural change by altering change and has also presented research at more long-held regional identities. than 50 regional, national and international con- The wine industry likely can adapt to the ferences on climate-related issues. His family possible changes in climate, but not without also has a vineyard and in the Umpqua help. Today many of the wine Valley of Oregon. E-mail: [email protected]

28 Geotimes n August 2004 www.geotimes.org