The news: Early tastings of Bordeaux 2010 suggest it is probably just as good as the 2009, described as the vintage of the century.

The received opinion: This is because of global warming, which produces riper grapes, and better wine quality.

Wine experts are not climatologists. But wine literature is full of gobbledygook about global warming's short-term benefits (which is said to have dramatically improved fruit quality in many regions) and long-term perils (which is predicted to destroy the wine industry).

The theory that the wine industry will have an epiphanic moment before dying out has caused winemakers considerable alarm and launched more than one seminar on the subject. Climatology is far from an exact science and one problem with much of what is written on the subject is sweeping generalisation. Even if one sets aside the controversy over the ‘official data' on warming — the United Nations panel estimated that the average global temperature increased by 0.74 degree C in the 20th century — the world is not warming evenly. For instance, Germany recorded the lowest temperature ever in 2009 and New Zealand had record late snowfall in 2009.

If we understand that global warming is often used in wine literature as a mere euphemism for warm summers in certain wine-growing regions, then the argument is persuasive, but considerably less dramatic or alarmist. There is enough evidence — backed by studies — to show that dry springs followed by warm summers have a distinct impact on the ripening of grapes, enhancing their fruit flavours.

So how does one explain the fact that we have had so many good vintages in the recent past? The 20th century has thrown up at least three great Bordeaux vintages — 2000, 2005 and 2009 — and probably one more in the 2010. We have also had notable years in 1989, 1990 and 1995, but if one looks back further, we would probably have to settle as far back as the 1961. Is it merely an accident then that the weather has been kinder to Bordeaux over the last couple of decades? Doesn't this make a strong case for global warming?

These questions are best answered in a roundabout manner — or by drawing attention to the relative absence of really bad or indifferent Bordeaux vintages in the recent past. Take 2008 for instance, when the weather was awful and dire predictions about a disastrous vintage were surprisingly belied.

In our obsession with the global warming theory, what we often ignore is that winemaking and viticulture practices have improved vastly over the last couple of decades. The wine industry is armed with the technology now to overcome — or at least mitigate — the impact of inclement weather. Also, given the huge global interest in wine, and the resulting spike in prices, the industry has considerably more financial flexibility in producing good wines — for instance, by being more selective about the grapes it uses and by curtailing production.

While there will always be people willing to fork out obscene sums of money for rare vintages (say, a 1947 Cheval Blanc), on average the more recent ones are probably far better — at any rate, much more consistent in quality — than those in the remote past.

The chances are that wine will only improve in terms of quality and consistency in the future. Of course, it is another matter altogether if the dire (and disputed) predictions about how much the globe will warm in the 21st century turn out to be correct.

Keywords: Global warming