Published online 4 November 2003 | Nature | doi:10.1038/news031103-3


Wines bask in rising temperatures

Warming is increasing vintage ratings but could threaten flavour in future.

Average temperature in most wine regions may rise 2 ºC over the next 50 years.Average temperature in most wine regions may rise 2 ºC over the next 50 years.© GettyImages

Rising temperatures are giving some of the world's top wine regions a boost and fuelling new vineyards. But warming could also threaten the distinctive flavour of some harvests, says climatologist Gregory Jones of Southern Oregon University in Ashland.

"In most regions over the past decade, every year has been great for wines," Jones told this week's annual meeting of the Geological Society of America in Seattle, Washington. "Undoubtedly, climate played a significant role in this trend."

Jones studied 30 types of wine from 27 different regions, including parts of France, Italy, Portugal, Germany, California, Chile and South Africa. He found close links between vintage ratings - a zero to 100 scale - for each wine and climate records from the past 50 years.

The temperature rose by an average of 2 ºC during this time, and wines experienced an average rating increase of 13.3 for each degree. This is enough to bump a 'good' wine into the élite category of bottles ranked higher than 90.

To look to the future, Jones used a global climate model developed at the Hadley Centre for Climate Prediction and Research in Bracknell, UK. It forecasts a gain of a further 2 ºC for most wine-growing regions over the next 50 years.

As temperatures climb, vintages become more consistent, says Jones. This could be good news for areas such as Germany's Rhine valley, which has big swings in quality from year to year.

Warmer temperatures are already allowing vineyards to spring up in northern areas where grapes couldn't survive just a few decades ago. England's fledgling wine industry, for example, could improve in the coming years if the current climate trend persists, says Jones. "It may not be the best wine region in the world in 50 years, but it could get better."

“Grape-growers need to be aware of the change in climate.”

Gregory Jones
Southern Oregon University

But warming spells trouble for hotter areas that are already producing consistently good vintages, including Italy's Chianti region and the northern Rhone valley in France.

Average temperature in the Rhone valley has gone up by around 4 ºC over the past 50 years. If this trend persists, harvests could come earlier, exposing picked grapes to warmer temperatures. Grapes that ripen too quickly have the right amount of sugar, but may produce a wine that is short on flavour.

Jones is confident that the industry can handle the shifts. "Grape-growers can deal with the change in climate, but they need to be aware of them," he says. 

Southern Oregon University