The world is going to heat to such an extent that Burgundy may no longer be able to grow Pinot Noir, a conference heard last week.
Wine character as we know it today is on the verge of radical change, world experts on global warming and vines told the first World Conference on Global Warming and Wine held in Barcelona on March 24-25.
According to authoritative computer climate models, over the next 50 years Bordeaux is set to rise by 1.2C, Napa by 1.2C, Barolo 1.4C, Rioja, where water is already an issue, by 1.3C, Portugal – which is already up 2.9C over the last 50 years – by 2C. The list of 50 locations had been compiled from global research presented by climatologist Gregory Jones from Southern Oregon University.
Led by Bernard Seguin, a global bioclimatologist based at France’s national agricultural institute (INRA) in Avignon, scientists defined other regions where temperatures are already near top of the range for the grape varieties that over the past centuries of viticulture have been found to work best there. Drought is also a growing problem.
These include Penedes and La Mancha in Spain, Chianti and Southern Italy, Southern France, Hunter Valley in Australia, parts of Chile and the Central Valley of California.
Southern Hemisphere temperatures in vineyards in New Zealand, southern Australia, parts of Chile and South Africa will rise more slowly due to more water, and less land mass.
The changes in temperature will have a variety of effects on viticulture. Some reds may lose color, some wines will lose varietal flavor, some whites may disappear, said renowned Australian viticulturalist Richard Smart. ‘The effect will be profound,’ he said.
Smart also drew attention to the dangers of vine infestation as temperatures rose, particularly in the case of the glassy-winged sharpshooter, which spreads the fatal Pierce’s Disease, and the aphid hyalestes obsoletus, which spreads a phytoplasma disease called Bois Noir. Higher temperatures mean both insects will be able to survive winters and move further. Hyalestes Obsoletus has recently been found in German vines.
The point was made that while it might seem almost trivial to draw attention to the dangers of global warming to the wine industry when so many staple crops were threatened, the vine’s extreme sensitivity to climate made it ‘the most direct and striking example of global warming’ as Seguin put it.
The conference called on governments to take heed of the warning signals and to invest in grapevine breeding programmes to find varieties that will work in hotter temperatures, as well as improved irrigation systems, Greg Jones said.
Above all, the there are no certainties except for the fact of global warming. While we are not sure of the effects of hotter temperatures we know it will have a profound effect on vines.
Jones pointed out that ‘although the changes are only a few degrees centigrade, that is all that exists at the moment between the regions.’
Taking the Mean July Temperature of various regions he showed how their viticultural character would change if you add 2degreesC.
Santa Maria, with a MJT of 17.3C would become Napa, at 19.3, St Helena at 21.7C would become Stockton at 23.5C, Healdsburg would become Modesto, and Fresno, Bakersfield.
Written by Kathleen Buckley and Adam Lechmere
