"Global Warming: What are the Winemakers Doing About it?" by Clive Coates

Out there in the real world beyond the damask, the Riedel and the head chefs' egos there may still be a few who believe that the world is flat. There are certainly those who, astonishingly enough in view of the contrary scientific evidence, persist in believing in Intelligent Design, whom we used to call Creationists. There may indeed be some left who still consider it a good idea to sell arms to corrupt and oppressive regimes, on the basis that the mad dictators who rule them are, temporarily at least, against the same people that we are.

But surely there can be no one left who does not accept Global Warming? Who or what is responsible for shrinking glaciers and rising sea-levels is an argument which has no place here. But the effect of global warming on viticulture and viniculture, the potential threat to wine styles and wine and food matches is another matter, and that is what I am going to attempt to address in this column. It is ironic that, just as we are now beginning to produce good wine from almost any grape variety you could care to mention in almost every country in the world – just as, to put it in a nutshell, man has finally mastered the art or science of wine-making – nature should be skulking round the corner ready to bludgeon us with a blunt instrument called climatic change. We are going to have to go back to square one and think out our ideas through all over again. 

Until relatively recently life for all those involved in the wine business was very different. We didn't understand the science. We didn't have the treatments we needed to keep our vines and their fruit healthy. We hardly knew whether it would rain tomorrow or not. Only a limited few were interested in consuming better wine than the local jug stuff. And none of those at the production end made a profit.

Like any other agriculturalist the viticulturalist’s aim was to produce quantity: to encourage nature to do its thing. But there was very little to encourage perfectionism. Nothing, indeed, but amour propre. Thank you to the proprietors of Lafite and Romanée-Conti who realised that someone had placed something sacred in their hands. 

Today at the top level estate managers are spending a great deal of time and money reducing the crop, and then isolating the issue of the junior vines into a second wine. We are fighting against the energies of nature. It's a great paradox. We are in more command of the science, and we certainly have all the controls over temperature and so on that we would wish. Weather forecasting could be a lot more reliable, but for the next five days it is reasonably accurate. Most importantly all the world drinks wine, and with today's techniques there is nothing to stop us producing something enjoyable almost anywhere we like, and for all those in the pipeline to make a good living on the way. 

Perhaps for the majority of the world's wines, global warming, provided it does not get too excessive, will not do any harm. In lands like Chile, for example, vineyards at the northern end of the country, if they become too warm and too dry, will just be abandoned in favour of new plantations further south. This principle will be applied all over the world. It will be expensive to relocate, of course: planting a vineyard from scratch is not cheap. Access to water will become even more important than it is today. And water, clearly, is going to become more and more expensive in the decades ahead. But I don't consider that the wines which will result will become greatly different in character than they are today.

They'll just come from different places. Alaska or Tierra Del Fuego, anyone?

Where the threat really lies is at the Great Wine end. What, after all, is it that distinguishes a great wine from the competently-made bottle that sits next to it on the shelf. The answer, I suggest to you, is a question of depth and complexity, elegance and a sense of somewhereness. In short: terroir. Just as in Animal Farm, where some animals are more equal than others, so some terroirs are superior to others. It's not all the vineyards in Burgundy or Bordeaux, to take two areas I know something about. But those vineyards on which lie the classed growths and their equivalents, or which are already designated grand cru and premier cru. These bits of land are special. You won't find a convenient substitute a couple of hours away where it is a little cooler. 

The wine-maker has a dual task here. The first, obviously, is to make the very best wine he/she can. The second is to preserve, even enhance, the integrity and signature of the terroir. Why have all these permiers and grands crus – 550 in the Côte d'Or alone – if they are not going to produce individual wines, each with its own special nuance? While modern methods are making life easier for the winemaker to more consistently come up with something fine, global warming is tending to impose a uniformity on the results.

Sixty years ago the vintage in Bordeaux and the Côte d'Or began in the last week of September. Whether it actually stared on the 25th or the 28th often merely depended on which day was a Monday. It was just more convenient to begin at the beginning of the week. If you take the average since 1945 – irrespective of the fact that 1945 itself, followed by 1947 and 1949, were all hot vintages – you can see that every decade the vintage begins three or so days in advance of the previous one, so that the average is now a harvest date in the first week of September. In the last decade we have had three vintags which began in August: 2003, 2007 and 2011. The only previous August vintage in anybody's records is 1893.

The days at the start of September are sunnier, warmer, and more likely to be drier than they are three or four weeks later. In fine weather ripeness gallops towards fruition in any case, but today the process is faster than ever. For the white wine grower this is a potential nightmare. In the production of white wine the acidity is all important. Miss the optimum day and your wine is compromised. It is the explanation why 2008 and 2006 are better vintages, overall, in the Côte de Beaune than 2005 and 2009, despite the much better weather conditions in these latter vintages. Many white wine vineyards were cleared too late. Christian Moueix will tell you that he picks Pétrus only in the afternoon. By this time the dew has evaporated and his fruit arrives in the winery with another half a degree of potential sugar. I can envisage Burgundian white wine makers considering doing the opposite!

What the best of the white winemakers can do, and the recent epidemic of prematurely oxidised bottles has encouraged this, is to produce less ephemeral wine. If you are, say, a grower in a Puligny premier cru you are getting enough for your bottle not to be forced to squeeze every last drop out of every single grape. Press more gently and you'll get a better and more concentrated wine (think of Champagne or think back, if you are as decrepit as I am, to 1973, 1979 and 1982. These were all three huge vintages. Pressing didn't have to be continued to the maximum. There was enough juice anyway. (The result: three excellent white wine vintages.)  A further feature would be to avoid, or halve, the malo-lactic fermentation. Jadot does this. Why not others? 

Red wines, in Burgundy at least, are so far benefiting from the earlier harvests, though for how long, given the notorious fragility of the Pinot Noir, I hesitate to guess. We can today expect better colours, healthier and more concentrated fruit, and in all but the very hottest vintages, a more enhanced relationship between the wine and its terroir. Moreover, the red Burgundy producer can play around and permutate between long or short cold soaking before fermentation, the use or rejection of the stems, the temperature—28°; 30°, 32° (Celsius) and upwards—and length of the fermentation and maceration, and the amount of new oak. With 2009 it became obvious that a large number of young men and women in the Côte d'Or were doing little experiments on the side. Were the techniques they had performed for the last decade or more really the best? Should they be more flexible?

Bordeaux is another matter. It tends to be hotter than Burgundy in August and September, and the varieties employed – principally Cabernet and Merlot - tend to be more tannic, and in the case of the latter, less acidic, than Pinot Noir. For 30 years I have participated in three- and ten-year-on tastings of the best. The first growths and their equivalents are served at the end. In the 1980s most of us, a group of buyers for the leading UK wine merchants, would be disappointed if we had not guessed at least four out of the eight correctly. Today the only château I would feel confident of isolating would be Haut-Brion. I'm not the only Bordeaux lover who finds the wines increasingly similar.

If the acidity level is what is all-important in top white wine production it is the level of alcohol in the reds which often separates the fine and elegant and terroir expressive from the merely rich and fruity. Here global warming poses another threat. We want the habitual 100 days or more between flowering and harvest. This is the length of time (which we didn't have in 2003) we require for the tannins to become ripe and sophisticated. A first of September harvest means a first of May mid-flowering, and that requires benign weather conditions in the Spring. If April and May are cool, and June, July and August uneven—which they are not all every year in the middle of France, but still in the majority of cases—we are sitting comfortably. Nothing will ripen properly before September 18th or so. But if the Spring is precocious, as it was in 2011, or if the summer is very hot, the fruit will ripen rather earlier. There is a limit to how long we can delay picking before the fruit begins to rot.  The danger is that the tannins are still only marginally ripe but the wine weighs in at 14.5° or so. About the only solution, given overall temperature control in the winery, is to multiply the number of pickers by a factor of three or four, and once you have started picking to continue 24 hours out of 24 until every grape has been collected. And yes, you'll have to double the size of the winery and the number of fermentation tanks. 

Too many wines, all the way around the world, are already made with acidity levels which are for my palate too low, and with alcohol levels (ditto) which are too high. Is this really what the customer wants, or is it more that these wines are picked out by the critics? The bigger wines stand out alongside those with less muscle and guts. But this is in the absence of food and leisure time, which is the real point. These wines are certainly much less food friendly than the fresher, less tannic, less alcohol-hefty examples you are more likely to find in France and Italy than California. These we can match with food. These are made for drinking, not analysing. We may even enjoy them so much we'll order another bottle; while even the first representative of the opposite category goes unfinished.

Sadly global warming is not helping the production of fine-for-food wines. Yet I remain an optimist. An elitist optimist perhaps. For the time being there are enough of these wines. What I say is give the customer not what they think they like, but what they should like. The task is ours. Once we have convinced them they can encourage all those involved in the production and sales of food-friendly wines, however strange the provenance may seem at the outset. They may well be all sorts of so far undiscovered great terroirs; inconceivable today, but which may be eminently suitable for the wine industry in 2112.

Clive Coates MW is one of the world's leading wine writers and critics. His latest work is The Wines of Burgundy, (University of California Press). His website (www.clive-coates.com) deals mainly with Burgundy, which is where he lives.