Whereas conventional vineyard techniques had evolved in northern growing areas where optimal ripening was a struggle, now, ripeness is achieved more easily and quickly.
"We are returning to a more conservative approach, diminishing canopy sizes, picking slightly earlier and reducing vine vigor to allow the vines to better manage the resources in the soil," he said.
In Burgundy, where sun and heat can be a boon, there is some cautionary optimism about global warming. "The vines flower very early now," said Marie-Andree Mugneret, co-owner of Domaine Georges Mugneret-Gibourg in Vosne-Romanee. "If I told my grandfather we were picking grapes in early September, he would say it's impossible.
"For now, it seems a good thing; the concentration of flavors is there. But we just don't know what the future will hold."
Burgundians worry that alcohol levels may rise high above 14 percent in pinot noir, the dominant grape there. Possible soil damage is also a nagging concern for enologist Gautier Romani of Chateau de Pommard.
"I fear that global warming will affect the soil underneath the top layer. It will become compacted and micro- organisms in the soil will be affected," he told me. "The vineyards will change but we don't know how."
In Portugal's Douro Valley, home of Port, winemakers are confident that hundreds of years of experience will enable them to cope, says Robert Bower, sales and export manager for the Fladgate Partnership Vinhos, maker of Taylor, Croft, and Fonseca Ports.
Though there's no definitive evidence yet, "if global warming comes to the Douro, the Port producers can adapt with the variety of elevations and various aspects to the sun available in a port vineyard," he says. "If the year is warmer than they would like, winemakers can use more grapes from higher elevations or use more grapes from a northerly aspect to the sun."