Wine- the real crisis

This weekend, I woke up to a horrifying message from a friend. This screenshot from mic.com.

In all seriousness, whether or not wine will become more expensive or harder to come by as the effects of climate change begin to be felt is a minor issue (understatement of the century) compared to other predicted effects, particularly those affecting people in the Global South. However, given how widely reported this story has been I thought it would be interesting to check out the science behind it.

The headlines were triggered by the International Organisation of Wine and Vine’s (OIV) latest report. It reports a fall in total production of 5% compared to 2015, making this year’s production among the three worst this century. 

Image 2: Trends in global wine productions using OIV data.

It has been reported in many articles (including in The Guardian, CNN and The Independent) that this is attributable to climate change. In the OIV’s press release they briefly mention that South America was ‘strongly affected by climatic events’. The OIV’s Director General reportedly added “output was greatly affected by exceptional weather conditions. If there is one product that is vulnerable to weather events, it’s wine,” and "with global warming, we're witnessing an increase in exceptional events that are more frequent, longer lasting and of greater scale."

Let’s examine these claims one by one.

Firstly: could ‘climatic events’ really explain the fall in production in South America? The climatic event in question is El Niño, a reversal in usual weather patterns in the South Pacific. It causes dramatic changes in rainfall patterns and temperatures across the Southern hemisphere. This year’s El Niño is one of the most powerful ever recorded and had massive impacts, including droughts in Brazil and floods and landslides further south. It’s pretty much inevitable that destructive climate events of this scale result in overall reductions is agricultural productivity, and grapes are no exception.

It’s also true that climate change is likely to exacerbate these effects. There has been a lot of speculation and debate for a long time about how climate change may affect El Niño events, but a recent study concludes that these events will become stronger and more frequent with climate change.

But what about elsewhere? Much of the decrease in production is indeed attributable to South American countries. For example, production in Brazil decreased by 50%. However many other countries also saw a fall in wine production. The biggest absolute decrease in wine production occurred in France, which accounted for more than a third of the total global decrease.  El Niño mainly affects the South Pacific and neighbouring regions, and although it is true that more local climate events can have knock on impacts around the globe, it is unlikely that El Niño was the sole cause of wine production decreases in Europe.

So could anthropogenic climate change also be affecting wine production? A 2014 review paper published in the journal ‘Wine Economics and Policy’ suggests climate change will affect wine production in a number of ways, including reducing both productivity and the land available for vineyards, requiring changes in grape varieties grown, causing fundamental changes in wine chemistry, and increasing pests and diseases attacking vines. It also corroborates the above statement about the susceptibility of grapes to changes in climate (although given that the paper features the line ‘wine is not essential to human survival’ some may be inclined to reject its findings completely).

Another paper published in Nature Climate Change earlier this year compared past climate records to vineyard records in France and Switzerland. It found that although recent climate change has in fact resulting in some outstanding vintages, the current decoupling of summer heat waves and droughts is likely to negatively impact future wine production. 

It seems that the assertions in these media stories are true. However, as is often the case, the headlines don’t accurately represent the actual stories or the OIV report they’re based on. The OIV’s tiny mention of ‘climatic events’ refer to the most recent El Niño,and the Director General’s follow up comments (rarely even mentioned in media stories) to its interaction with climate change.  Headlines such as ‘Attention wine lovers: You might want to start paying attention to climate change’, while factually correct, don’t accurately reflect the article or the report on which it is based.

Looking at the graph above, it s also clear that this year’s overall production, although genuinely lower than recent averages, is not as low as headlines like ‘Global Wine Production Is Collapsing Thanks To Climate Change’ suggest.

As always then, this story is a reminder to always take media hysteria with a pinch of salt. And if in doubt about the science- send it this way!