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Winegrowing regions and climate change

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Grapes grown to make wine are sensitive to climate conditions including temperatures and amount of rainfall.  The warming climate is already having visible effects on yields, grape composition, and the quality of wine.  This has significant consequences on the geography of wine production and is of major concern for the $350 billion global industry.

Winegrowing regions are mostly at the mid-latitudes where temperatures are warm enough to allow grapes to ripen but not excessively hot.  The climates are relatively dry so that fungal diseases are not rampant.

Because of the warming climate, harvesting in most vineyards now begins two or three weeks earlier than it did 40 years ago and this affects the grapes and the resultant wines.  Temperature changes affect acidity, wine alcohol, and aromatic signatures.

If global temperature rise crosses the 2-degree level, 90% of all traditional winegrowing areas throughout Spain, Italy, Greece, and southern California may become unable to produce high-quality wines.  Conversely, areas of northern France, the states of Washington and Oregon, British Columbia, and Tasmania will see improved conditions for producing quality wines. 

As the climate warms, winegrowers face new challenges such as the emergence of new diseases and pests as well as an increasing number of extreme weather events.  Wine producers are using more drought-resistant grape varieties and are adopting management methods that better preserve soil water.

The changing climate poses many threats to the quality of wines produced in traditional vineyards.  In the future, the wine industry may look very different in terms of where and how the best wines are produced. 

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A global map of how climate change is changing winegrowing regions

Photo, posted November 14, 2008, courtesy of Curtis Foreman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Protecting wine grapes from wildfire smoke

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In recent years, wildfires have become a major threat to the wine industry because of the effects of smoke on wine grapes.  Smoke taint from the California fires of September 2020 significantly impacted the quality of wine grapes.  In total, smoke taint cost the wine industry in Western states more than $3 billion in losses from the hundreds of thousands of tons of wine grapes that could not be harvested because of the off flavors imparted by the smoke.  The California wine industry alone is a $43 billion a year business and the state’s frequent wildfires are a major threat to it.

Researchers at Oregon State University have developed techniques for eliminating the effects of three volatile chemical compounds that contribute to smoke taint in grapes.  The compounds are guaicol, syringol, and meta-cresol.

The researchers developed cellulose nanofiber-based coatings that can be applied to grapes in the vineyard.  The coatings can block guaicol and syringol and capture meta-cresol.

Blocking is ideal because the coating doesn’t absorb the wildfire smoke compounds.  Therefore, it doesn’t have to be washed off.  Capturing means the coating absorbs the compounds and would need to be washed off.  Ideally, a coating that doesn’t need to be washed off would save time, money, and water.

Two years of studies at Oregon State found that the coatings do not impact the growth and quality of wine grapes.  In an era when wildfires are increasingly common and extensive, growers need something they can spray on their vines to protect their grapes.  If the Oregon State technology can be commercialized, it would be a game-changer for the Western U.S. wine industry.

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Spray coating for grapes shows promise in battle between wildfire smoke and wine

Photo, posted October 3, 2006, courtesy of Naotake Murayama via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Here Come The Lanternflies | Earth Wise

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The spotted lanternfly is an invasive pest from Asia that primarily feeds on tree of heaven, which is itself an invasive species that has become widespread.  The real problem is that the lanternfly can also feed on some 70 other plants such as grapevines, maples, fruit trees, and more.

The lanternfly was first discovered in the US in Pennsylvania in 2014 and has since spread to 14 states including New York, Massachusetts, Connecticut, and Rhode Island.  (It was first spotted in New York in Staten Island in 2020 and has continued to spread).

The insect poses a significant threat to New York’s agricultural and forest health. Both the adults and nymphs feed on the sap of plants which stresses them making them vulnerable to diseases and other insect attacks.  They also secrete a sticky substance that attracts molds and interferes with photosynthesis.

Lanternflies are not strong fliers.  They mostly spread through human activity by laying their eggs on vehicles, firewood, outdoor furniture, and other objects that people transport.

The bout of unusually warm weather that the Northeast experienced in early spring is likely to have jumpstarted the spotted lanternfly timeline and hatching could be bumped up to as early as May.

Agriculture officials are asking for people to look for spotted lanternfly egg masses and scrape them off with implements with a sharp edge.  Adult insects should be reported to local authorities and should be killed if at all possible.  There is lots of information online about how to recognize the egg masses and the insects.  Spotted lanternflies are not a direct threat to humans, but they have the potential to cause great harm to vineyards, orchards, and forests.

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Spotted Lanternfly

Photo, posted September 12, 2018, courtesy of the U.S. Department of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Spotted Lantern Fly Is A Big Problem | Earth Wise

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The spotted lanternfly is an invasive pest from Asia that arrived in the United States seven years ago.  It is a handsome and colorful insect, but it feeds on the sap of more than 70 plant species, leaving them susceptible to disease and destruction from other natural antagonists.  It destroys fruit crops, trees, and plants by hopping from plant to plant, crop to crop, and tree to tree.

Several states have established quarantines aimed at preventing the spread of the insects.  Pennsylvania, where they were first detected in the U.S., issued an Order of Quarantine and Treatment that imposes fines and even potential criminal penalties on anyone who intentionally moves a spotted lanternfly, at any stage of its life, from one sort of location to another.  The insects hop and fly only short distances, but they can hitch a ride on vehicles, clothing, and other objects that people bring with them.  They have now spread to at least nine states, primarily in the Northeast.

Lanternflies arrived in New York City last year and quickly made it to the Most Wanted List for environmentalists.  The City’s Parks Department says: “If you see a spotted lanternfly, squish it, dispose of it, and report it to us.”  New York’s Department of Agriculture has asked people in the Finger Lakes region, home of numerous vineyards, to collect specimens and provide specifics on where they were found.

Lanternflies are harmless to humans, but they threaten everything from oak, walnut, and poplar trees to grapes, almonds, and fruit orchards.  As the species continues to spread across the country, federal and state officials have a unified message:  if you come across a spotted lanternfly, kill it.

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Die, Beautiful Spotted Lanternfly, Die

Photo, posted August 30, 2018, courtesy of the USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wine And Wildfire Smoke | Earth Wise

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Rising global temperatures have made droughts and heatwaves more common and intense, leading to larger and more destructive wildfires.   In 2020, wildfires in California blackened more than 4 million acres, the largest wildfire season on record.   With its continuing drought, California has already had 1.5 million acres burned by wildfires this year, and the fires continue.

Wildfires can cause extensive damage throughout the agricultural industry by destroying crops and killing livestock.  But the fires can have a unique effect on the wine industry:  wine grapes can be affected by smoke taint.

Vineyards have demonstrated themselves to be good fire breaks.  They definitely help prevent the movement of wildfires.  But there is no way to stop smoke from the fires from drifting into vineyards.  By far, the damage caused by smoke far outweighs direct losses from fires in vineyards.

Winemakers sometimes add subtle smoky notes to their vintages by aging them in toasted oak barrels.   But wildfire smoke permeating vineyards – even from distant blazes – can end up making wines undrinkable.  Smoke-tainted wines end up having unpleasant aromas that people describe as being like disinfectants or burnt rubber. 

With wildfires an increasingly persistent presence in California, the state’s $43 billion wine industry is facing a major challenge.  An estimated 165,000 to 325,000 tons of California wine grapes went unharvested last year, adding up to more than $600 million in losses from fire and smoke.  The industry will need to figure out ways to detect and manage smoke taint as the problem isn’t going to go away.

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Wildfire Smoke: An Emerging Threat to West Coast Wines

Photo, posted July 25, 2021, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fighting Mildew With Robots | Earth Wise

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Cornell Researchers have partnered with Norwegian company SAGA Robotics to develop autonomous robots that can roam vineyards at night armed with ultraviolet lamps that can kill powdery mildew, which is a pathogen that devastates many crops, including grapes.

The robots are being field tested on Chardonnay grapes at two sites:  Cornell AgriTech’s research vineyards in Geneva, New York, and at Anthony Road Wine Co. in Penn Yan, New York.

Cornell has been researching the use of UV light to kill grapevine powdery mildew for nearly 30 years.  They have also worked with the University of Florida on using it to control powdery mildew in strawberries.

The UV treatment has been shown to suppress powdery mildew over a period of two years with the application of treatments once a week.  The technique represents a breakthrough because the mildew can adapt to chemical anti-fungal sprays in a single season, making them ineffective.  UV light damages DNA, but mildews have natural biochemical defenses that are triggered by the blue light present in sunlight.  By applying the UV at night, when there is no blue light from the sun, the defenses of the mildew are defeated.

In earlier trials, the researchers used UV lamps mounted on a tractor wagon, but this required all-night labor to treat an entire vineyard.  That has now been replaced with autonomous vehicles that can work seven nights a week, all night long.

The next development will be imaging technology that will detect and quantify mildew on grape leaves.  With this, the dose of UV light applied to a particular vine will depend on whether it is sick or healthy.

A high-tech solution to a problem that plagues vineyards.

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Robots armed with UV light fight grape mildew

Photo courtesy of Rodrigo Onofre/Twitter.

Earth Wise is a production of WAMC Northeast Public Radio.

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