Over the last 100 years, California’s average temperature has risen a little more than 2 degrees Fahrenheit. Predictions suggest that this trend will continue and accelerate in the coming decades, with temperatures rising more than 2 degrees in the next two to three decades. Much of the climate change is due to the release of greenhouse gases, including carbon dioxide (CO2) and nitrous oxide (N2O), which can be generated through a host of human activities, including agriculture, manufacturing and transportation. Consequently, the wine industry is looking at ways to reduce its greenhouse-gas footprint and is exploring options to become net-zero, or even net-negative in terms of its emissions.
Businesses must consider two questions when it comes to dealing with what is increasingly being referred to as the climate crisis. The first is how to respond to changing climatic conditions in the short term. The second is how to do their part to help remedy the situation. In either case, understanding the baseline data is important.
Putting it in perspective
The average car emits about 6 tons of CO2 every year. Burning one gallon of gas creates 20 pounds of carbon dioxide. On average, making, shipping and consuming a bottle of wine creates about 2.25 pounds of carbon, nearly 40 percent of which comes from the glass bottle itself, according to the Wine Institute.
On the vineyard side, about 8 percent of greenhouse-gas emissions come from agricultural, crop-related businesses. California has about 27 million acres of cropland, with about 650,000 acres dedicated to winegrape vineyards—about 2 percent of the total cropland. That might seem like a drop in the bucket; however, the climate-friendly practices being employed in typically well-funded vineyard operations are often applicable to many other crops.
Sources of the problem
According to the FIVS International Wine Greenhouse Gas Protocol, the primary contributors of greenhouse gas emissions include consumption of electricity, and combustion of fossil fuels for heating, cooling and operations, within the winemaking process. Additional emission sources can result from recharging cooling systems (refrigeration, air conditioners, etc.) and CO2 used in the winemaking process (dry ice, blanket tanks, pipe flushings, etc.). Similarly, in the vineyard itself, greenhouse-gas emissions are generated from the combustion of fossil fuels by operational equipment such as tractors and forklifts, onsite waste disposal (composting and incineration) and field emissions, particularly N2O, which is generated through natural processes but also by human activities such as the application of synthetic fertilizers and tilling the soil.
The Intergovernmental Panel on Climate Change (IPCC) highlights that within vineyards and other crops N2O is of a particular concern. Nitrous oxide is produced within soils naturally through the process of nitrification and denitrification, but N2O is released when nitrogen is added to soils in the form of fertilizers, both organic and synthetic. According to the IPCC, use of synthetic fertilizers in agriculture is one of the largest sources of N2O production and has 265 times the 100-year global-warming potential of carbon dioxide. Emissions also occur following soil cultivation such as tilling and other land-management practices and potentially contribute as much as 50 percent of the total greenhouse-gas emissions within a vineyard, according to the Wine Institute.
Planning for a more volatile future
Temperature increases can result in fueling extreme conditions such as floods, temperature spikes, droughts, higher winds, severe frosts and increased fire risk, all of which can affect wine industry stakeholders (vineyard, winery, packaging or distribution companies). Therefore, effective strategies must be developed, and contingency planning should remain nimble and updated as conditions evolve.
In the vineyard, non-till farming and shade-cloth implementation should complement fewer passes with tractors in existing vineyards. For those planning to plant/replant new vineyards, row orientation must ensure that on the hottest days of the summer the sun’s rays are equally distributed throughout the canopy. Vertical-shoot positioning is no longer vogue as it can result in sunburned fruit. Today, the use of trellis arms and vines that provide an umbrella for the grape clusters are preferred. Of course, selecting the most appropriate rootstock and cultivar for the site is also critically important and may include selecting varietals that are not typically considered, such as Merlot and even Cabernet Sauvignon in places where Chardonnay and Pinot Noir were historically grown.
In the winery, the biggest opportunity is to look for an alternative to heavy glass bottles. Here, there are plenty of interesting options: kegs, cans, boxes and even barrels are now readily accepted by the consumer.
For those who enjoy wine and would like to pick the ones that have the least greenhouse-gas emissions, the answer is relatively easy: Buy local because they don’t have to be shipped. You might also want to ask the winery about their climate-friendly policies. If they don’t have an answer, you then have yours.