LOUISVILLE, Ky. (WAVE) - Wine. It gets a lot of us through the week. Climate change may have an impact on that evening glass of wine.
A recent study showed that if global average temperatures rise by just two degrees Celsius, many wine growing regions may shrink by 56%. A four-degree jump in global average temperatures would leave 85% of wine-producing areas unable to create high-quality products.
It's not all bad news, though. There are ways producers can adapt to changing conditions. Switching where certain grape varieties are grown could decrease potential losses by half for two degrees of warming and by a third for four degrees of warming. There are quite a few options for growers; there are more than 1,100 varieties of grapes planted. This study focused on the following varieties: cabernet sauvignon, chardonnay, merlot, pinot noir, riesling, sauvignon blanc, and syrah.
Researchers have found that cool wine-growing regions like the Pacific Northwest, New Zealand, and Germany would be relatively unaffected by a two-degree Celsius rise in global average temperatures. This means that these areas could become more suitable for merlot and grenache since they prefer warmer temperatures. Warmer growing regions, like Italy and Spain, would be the most impacted by warming.
Here's why the temperatures are so important. It is harder for grapes to ripen in cooler climates. Less ripe grapes have higher acidity levels, which can give them a sour or tart flavor. There's also lower sugar levels in less ripe grapes, which leads to lower alcohol content. Grapes also need plenty of sunshine to ripe, regardless of temperature. Remember, climate change does not just mean warmer temperatures but also a change in the type and location of precipitation. More clouds and rain can lead to less ripe grapes.
Too much rain can lead to higher moisture content in grapes; this can dilute the raw material used for wine production.
Warmer temperatures aren't entirely bad. Grapes have higher sugar content, lower acidity and darker color since the ripen faster in warmer climates. Higher sugar content means a higher alcohol content in wine.
There’s a negative side to the warmth though. A growing season that’s too hot will force grapes to ripen too quickly. Too much sunshine can actually sunburn crops; vines can even shut down to protect themselves from the heat.