Napa Wine Quality may Suffer Climate Change
According to a study conducted by researchers at the Stanford University in California, there could be 50% less land suitable for cultivating premium wine grapes in high-value areas of Northern California even as some cooler parts of Oregon and Washington state would become correspondingly better for growing grapes, writes Subhash Arora with divergent viewpoints expressed by experts like Cakebread, Torres and Pancho Campo MW, and yet all recognizing the results of the study and pointing in the same direction.
The researchers examined climate change over the next 30 years of four wine-growing areas Napa Valley and Santa Barbara County in California, Yamhill County in Willamette Valley in Oregon and Walla Walla in Columbia Valley in Washington.
Taking the premium wine grape suitability in the western USA including Napa Valley as an illustrative case study, the research focused on the evaluation in the near-term period years 2000–39. The report finds that ‘the projected warming over this period results in the loss of suitable wine grape area throughout much of California, including most counties in the high-value North Coast and Central Coast regions.’
It however adds that ‘in quantifying adaptation wedges for individual high-value counties, we find that a large adaptation wedge can be captured by increasing the severe heat tolerance, including elimination of the 50% loss projected by the end of this period in the North Coast region, and reduction of the projected loss in the Central Coast region from 30% to less than half. Increased severe heat tolerance can capture an even larger adaptation wedge in the Pacific Northwest, including conversion of a projected loss of more than 30% in the Columbia Valley region of Washington to a projected gain of more than 150%,’ adding that ‘we also find that warming projected over the near-term decades has the potential to alter the quality of wine grapes produced in the western US.
These results follow the researchers' 2006 climate study, which projected that as much as 81% of premium wine grape acreage in the country could become unsuitable for some varietals by the end of the century. For the current study the team assumed a 23% increase in greenhouse gases by 2040, which would amount to a 1˚C increase in global temperature.
Researchers used a climate model based on local, regional and global conditions and including factors like wind conditions and coastal variations. It was tested against actual data of 40 years, between 1960 and 2010. They predicted that by 2040 all four wine regions are likely to experience higher average temperatures during the growing season and an increase in the number of ‘very hot days’ when the temperature reaches 35˚ C. In Napa the average temperature could increase by more than 1˚C, with the number of ‘very hot’ days going up by 10. As a result, the amount of land suitable for growing Cabernet Sauvignon, Pinot Noir and Chardonnay would shrink by half. There would be slight increase in suitable land In Willamette Valley in Oregon, but in Columbia Valley in Washington there would be a 30% reduction.
Growers have two options, the report’s co-author of the study Noah Diffenbaugh, of the Woods Institute for the Environment at Stanford University warns, according to Decanter. They can either find grape varieties that can withstand up to 45 very hot days, or they can move their growing operations and employ a range of strategies, such as new trellising methods and irrigation, to keep vines cool.
"There will likely be significant localized temperature changes over the next three decades," said Noah. "One of our motivations for the study was to identify the potential impact of those changes, and also to identify the opportunities for growers to take action and adapt." High-value growers in California may need to take into account warmer weather and integrate climate information into their cultivation and practices, Diffenbaugh said. He identified Yamhill County in Oregon and Walla Walla County in Washington, as they are with a cooler climate.
Cakebread CEO reacts Positively
The issue of climate change, its causes, effects, and how we can diminish or alleviate them is something for which producers in Napa and elsewhere have shown concern, even before this report came out last Thursday. As Bruce Cakebread, CEO of Napa Based Cakebread Cellars tells delWine, ‘The issue has already driven policy at the California state level with the successful passage of AB 32 (the California Global Warming Solutions Act of 2006). The reduction of greenhouse gases (GHG’s) will likely become the cornerstone of decisions regarding not only farming and wine production practices, but business and industry across the board in California.’
While Bruce admits that in Napa valley they believe climate change is very real, how regions around the world are affected by the changes will be very different. ‘It is not a blanket effect, so local data and research is required,’ he stresses.
‘Two major research papers addressing the affects of climate change on the wine industry were published in 2006, notably a NASA/Purdue Study that specifically singled out Napa Valley, and as a result, scores of articles have been written in publications world-wide and Napa Valley has been the target of much of the discussion about the potential negative impacts of climate change,’ he informs delWine.
‘To date these major studies have been largely based on the 2003 Jones report commissioned by the Oregon wine grape industry which uses broad generalizations of west coast climate data to make predictions on the future of Napa Valley specifically. It does not take into consideration the complex system of the region’s micro-climates or the influences of the Pacific Ocean specific to Napa Valley.
The Napa Valley Climate Study (sponsored by the Napa Valley Vintners in 2006 and presented at Vinexpo in late June 2011) was completed earlier this year by Dr. Dan Cayan of Scripps Institution of Oceanography at UC San Diego and Dr. Kim Nicholas of Stanford University who studied under Chris Field who shared the Nobel Prize with Al Gore.’
‘After four years of examining 12,000 data points throughout the region, the conclusion is that what is needed is continued data collection to forecast what the future of Napa Valley might look like with global climate change since to date it is not happening. The data reveals the Napa Valley appellation has experience very minimal warming over the past fifty years—in fact only one degree Fahrenheit in overnight temperatures in winter to spring’.
‘In fact, the warmest years on record, globally, 1998, 2005 and 2006 have been the coolest years for the Napa Valley—a mix of the region’s very complex micro-climates, position in relation to the Pacific Ocean and the buffering mountains from California’s Central Valley make the forecasting wildly complex,’ stresses Bruce.
On a lighter note, Cakebread chirps, and says, ‘there is a reason Mark Twain said, “The coldest winter I ever spent was a summer in San Francisco.” Talking of several ongoing programmes to face the challenge he says, ‘here in Napa Valley we have several leading edge programs, Napa Green Land and Napa Green Winery programs which are designed to reduce soil erosion, protect stream waters for fish, reduce electricity, water and trash use and increase recycling and is third party certified for verification.’
Miguel Torres stresses need for more data
Reacting to a reported interview by a well known British journalist, I had asked Miguel Torres Sr. last year if it was true that he had bought vineyard sites in the cooler climes during the last couple of years. The shrewd visionary’s instant reply was that he had been buying such vineyards for over a decade. He has also formed a group of Spanish winemakers, headed by his daughter Mireia Torres, which studies the impact of climate change on the vines and the Spanish grapes and find ways of keeping them cool.
He was not available for comments since he is travelling but his son Miguel Torres Jr. who heads the family’s Chilean winery commented to delWine, ‘ I think that not only in California, but all over the world, we should be conscious of the most recent studies including the one that you mention and try to find solutions, but always with a back up by the data and with deep work and research behind it, and always comparing data from a scientific point of view, avoiding alarmist information that could also be biased.’
Citing the canopy management and irrigation techniques, he says, ‘Even if the temperature increases, there are ways to adapt the viticulture to slightly different climate conditions, as the way we work with canopy management and irrigation. It might be that in some areas of the world certain varieties will lose attractiveness but maybe others will have a new future,’ thus partially validating what has been said in the report.
Justifying the vision of his father Torres Sr. when he bought Spanish vineyards at higher altitudes, he says, ‘from my point of view, the key thing is to do everything we can in order not to get a higher increase in temperatures due to human causes, but also, we have to learn and finally to adapt.’
Pancho Campo MW, President of the Wine Academy of Spain and the Chairman of Wine Future 2011, being held in Hong Kong in November 2011, also feels the impact of climate change will be different in different wine regions but the factors remain about the same-the increase in temperatures, lack of hydric resources and climate variability the origin of most consequences.
Pancho laments the lack of enough efforts to negate the effects of the climate change and says, ‘ i believe that too much attention is being paid to mitigation and the wine industry is not focusing in the bigger picture, which is adaptation. If we do not reduce our dependence on fossil fuels and start using more renewable energy in order to drastically reduce CO2 emissions in the next 20 years, trust me, wine is going to be the least of our worries, in Napa, France or Spain,’ he tells delWine. He should know; he has focused a lot in the area of climate control during the last 4-5 years with a specific focus on Spanish vineyards.
Pancho further adds, ‘The wine industry has a moral obligation to address climate change and to protect the environment because our industry totally depends on nature and climate. Everyone from individuals to large corporations has to pitch in. We cannot wait for governments or organizations to solve the problem. We must act soon as we are at the verge of reaching the point of no return. Enough talk, enough green marketing, enough questioning the origin. We have a problem and we must tackle it immediately.’
NVV Climate Study