Napa Vintners Provide Climate Change Update

Complex Topic Requires Ongoing Thoughtful Review

Amidst another cool summer, Napa Valley again finds itself featured in various media outlets as the poster child for the potential results of climate change as it relates to, not just wine, but agriculture in general. Culturally, people are drawn to the romance of vineyards and since wine grapes, among all crops, are sensitive to vintage conditions and climate, there is more interest than say soy or oats or other crops.

The Napa Valley Vintners (NVV) acknowledges the climate research published this summer by an associate professor from Stanford, as well as all of the work done in this area over the recent decades, believing that the more attention and study given to this important global topic, the better off we will all be in developing ideas and tools for dealing with the potential impacts. Clearly, this is an issue of paramount importance to everyone, especially those of us in agriculture.

It was almost exactly five years ago that the Napa Valley Vintners Board of Directors established the Climate Study Task Force, comprised of a small group of vintners that had an awareness of, interest in, and passion for climate science and its possible effects on growing premium wine grapes, as well as wine production. The focus was to look specifically at Napa Valley, with its unique geographic position and resulting climate. It was this group of dedicated vintners that recommended the NVV work with Dr. Dan Cayan and his renowned team of climate scientists at Scripps Institution of Oceanography at UC San Diego. That officially launched the NVV's Climate Study Project, whereupon historical temperature and phenological data specific to the Napa Valley were gathered, analyzed and reported upon.

Over the next three years, the Climate Study Task Force collected data from 12,000 points in Napa Valley--from vintners, growers and weather stations. It was from this massive, grass-roots data collection that the Scripps science team assembled the "Climate and Phenology in Napa Valley: A Compilation and Analysis of Historical Data" report (Dan Cayan, Kimberly Nicholas, Mary Tyree and Michael Dettinger). This report, released in February 2011, indicated that Napa Valley has warmed slightly over recent decades, but not to the degree that has been previously reported. The warming we have experienced, 1-2° degrees Fahrenheit has taken place only in overnight temperatures between the months of January to August.

Not only did this study prove that we are not currently "tasting" climate change in a glass of Napa Valley wine, it also demonstrated what we all know to be true: the Napa Valley is indeed a unique place. Napa Valley is neither a coastal nor an interior climate, but shares traits of both: southern Napa Valley is more maritime-like, while central northeastern Napa Valley features some climate traits similar to California's coastal valleys. Daily and seasonal temperature changes in Napa Valley are higher than cool coastal climates, but less severe than warmer inland climates. Even though Napa Valley is not considered a coastal region, it is highly influenced by the marine layer, especially in the summer. Marine-influenced morning cloud cover mitigates daytime high temperatures, even though the clouds dissipate by early afternoon.

"Climate and Phenology in Napa Valley: A Compilation and Analysis of Historical Data" report's original media release and executive summary are linked below.

Climate change can and will affect all fine wine-growing regions worldwide, but the results will not necessarily be a blanket effect, as climate change is not a "once size fits all" phenomena. This is a very long-term issue which vintners and growers in Napa Valley need to continue to pay attention to and be directly involved with.

About the Napa Valley Vintners
The Napa Valley Vintners is the non-profit trade association responsible for promoting and protecting the Napa Valley appellation as the premier winegrowing region. From seven founding members in 1944, today the association represents 400 Napa Valley wineries and collectively is a leader in the world-wide wine industry. To learn more about our region and its legendary American wines, visit www.NapaVintners.com.

Read the executive summary of the Climate Report