Climate Change Now Affecting Grape Harvests and Wine Quality in France

By Ana Verayo / 1458646668
(Photo : Elizabeth Wolkovich/Harvard University) The best years for wine grape quality typically have warm summers with above-average rainfall early in the growing season and late-season drought.

Climate change is now changing the world of wine due to higher temperatures, causing French wine to be harvested two weeks earlier on average, according to a new NASA study.

Scientists warn that the quality of grapes will soon change due to ongoing drought conditions that have been the determining factor in making excellent wine. Earlier harvests traditionally result in better wine quality however, this new study warns about the consequences of climate change on harvests and the overall quality of the grapes.

Researchers investigated records of harvests and temperatures dating back to 1600 in France and Switzerland where data revealed that the earliest grape harvests occur during spring and summer, especially during highest peak temperatures. However, since climate change is changing seasons and weather patterns, higher temperatures are now arriving during non drought years which can upset the traditional harvest and quality of wine on a global scale.

Apart from these records, researchers also analyzed wine quality ratings of vintages from the Bordeaux and Burgundy regions in the last century where they discovered a link between wine quality and heat, that is on its lowest beginning 1980.

According to co-author of the study, climate scientist, Benjamin Cook from NASA's Goddard Institute for Space Studies, early harvests can only do so much for wine quality, for example, last 2003, when a massive heatwave spread across Europe, this led to earlier harvests that yielded mixed wine quality where nothing exceptional came out of it. He adds that, after a certain point, there is simply no benefit from global warming.

Researchers believe that these new findings can provide useful information for wine managers and those who need to plan in the next few decades about harvest times and producing quality grapes, since it will continue to get warm.

Cook says that climate change is fundamentally changing wine and that drought's effects are no longer crucial in producing excellent wine since weather and climate patterns are changing. He adds how there are some regions in France where grape growers have traditionally never included irrigation systems for their vineyards, depending on rainfall itself. Researchers also recommend that this practice would need change.  

Apart from wine growers in France, climate change is bringing in extreme weather events such as heavy rainstorms and hailstorms that are now increasing after summer heat waves, which can ultimately damage the grapes. Most French grapes require cooler nights however, winter and night time temperatures are becoming milder than before.

This global US $200 billion industry will be greatly affected, as viticulturists have no idea what to expect in the following warmer years. Cooks says that paying more attention how the climate changes is a good strategy for grape growers, to figure out management and harvesting plans before these changes arrive and become permanent.

This new study is published in the journal Nature Climate Change.