Global warming (or the more encompassing term climate change) is both a natural and an anthropogenic phenomenon (involving the impact of man on nature) responsible for the increasing average temperatures on the earth’s surface and oceans over time. Impacts include warmer days and fewer cold nights, heat waves, droughts, erratic seasonal cycles, and other extreme weather patterns. According to the Intergovernmental Panel on Climate Change (IPCC), a United Nations Environment Programme (UNEP) and World Meteorological Organization (WMO) initiative, the increase over the last century has been 1.33°F (0.74°C).
The major anthropogenic culprits of climate change are stratospheric ozone depletion and emissions of carbon dioxide, methane, nitrous oxide, and ozone gases, which are mainly the result of anthropogenic activities such as fossil fuel use and agriculture. These gases cause the so-called greenhouse effect, first observed by French mathematician Jean Baptiste Joseph Fourier (1768-1830) of Fourier transform fame in 1824 but not quantified until 1896 by Swedish physical chemist Svante Arrhenius (1859-1927). The greenhouse effect is a phenomenon whereby radiation by gases trapped in the atmosphere cause warming of the earth’s lower atmosphere, surface, and oceans.
The study and forecasting of climate change is a gargantuan scientific endeavor as it is based on very complex, highly-intertwined factors studied over long periods of time and on intricate modeling to predict future impacts. Though there is much debating in the scientific community-and the political arena-regarding the extent of climate change impacts and timing, one thing is for sure; climate change impacts are for real and the world must take prompt action to mitigate these.
How big of an impact is climate change on the wine industry?
Woods Institute for the Environment at Stanford University communications manager Mark Shwartz cites a 2006 study led by Noah Diffenbaugh, assistant professor of environmental Earth system science at Stanford which based on an analysis of historical temperature datafrom California, Oregon and Washington, concludes “that global warming could reduce the current U.S. wine grape region by 81 percent by the end of the century.” Now that is some apocalyptic prediction!
Over time, man has planted and replanted grape cultivars best suited to regional and local climates. For example, it is well known that Pinot Noir best adapts in cool-climate viticultural areas for making premium wine. The effects of global warming and climate change would then transform cool-climate regions into subtropical regions and subtropical regions into tropical ones. Cultivars adapted to one type of region would no longer be able to thrive in a different climatic region. It would be akin to trying to grow Pinot Noir in Central America today. Grapes would develop increased sugar levels and a corresponding alcohol increase, reduced acidity that will create balance challenges but likely without a commensurate increase in flavor profile-flavor development takes time, not necessarily more heat. Then, vineyards would need to be replanted by better-suited cultivars-quite the expensive proposition, particularly considering that, on average, it takes five years for new vines to produce wine-worthy grapes.
Failing that, vineyards will be faced with many new viticultural challenges such as: a shorter growing season which may not allow grapes to develop optimum maturity for making premium wines, increased irrigation which entails higher water usage, already a scarce resource, and significantly higher capital and operating costs, and a whole host of new pests and diseases that will require new technology and means to fight.
Whole businesses may be seriously impacted. Consider the existing situation in Germany where making Eiswein (Icewine) year after year is not a given since the necessary winter conditions are not guaranteed. If there will no longer be cold winters, there will be no deep freeze to make those lusciously sweet nectars of the gods and growing grapes in Champagne for making high-acid wines for bubbly will also become a challenge. On the flip side, we could see wines-perhaps even premium wines-being produced from non-traditional wine producing areas such as the UK and Scandinavia.
Although wine regions throughout the world have embraced and are implementing sustainable agricultural and winemaking practices, it behooves us all to become “greener” and support climate change mitigation measures-at least for wine’s sake.
* Excerpt from “WINE MYTHS, FACTS & SNOBBERIES: 81 Questions & Answers on the Science and Enjoyment of Wine” by Daniel Pambianchi (Véhicule Press, 2010).