Warming may help Northwest wine

Many Oregon winemakers have been striving to reduce their carbon footprints, but the warming climate may actually improve their bottom lines in the decades to come.

  "When it gets warmer, the cooler climates will be better off," said Orley Ashenfelter, economics professor at Princeton University and president of the American Association of Wine Economists.

  "I think the biggest effect is that you will be able to get more consistent high prices," he told the Capital Press at the association's recent conference in Portland.

  In fact, Ashenfelter believes Oregon's Willamette Valley has already benefited from slowly rising temperatures. Quality has clearly improved since Pinot noir production began in the region decades ago, he said.

  "Part of it is they know how to do it better, but part of it is that it's hotter," Ashenfelter said.

  Not only will the warmer climate make it easier to grow high-quality grapes from year to year, but it will also increase the available acreage for planting grapes - for example, on the valley floor, he said.

  The eastern part of the Willamette Valley may also receive more attention from grape growers, most of whom are currently concentrated on the western side, said Gregory Jones, research climatologist at Southern Oregon University.

  "People will start speculating in those next-best places," he said.

  Growers may also begin to have more varieties available to them, such as heat-loving Syrah, Merlot and Tempranillo grapes, Jones said.

  In terms of temperature suitability for growing Pinot noir, Oregon is currently near the edge of the spectrum, he said. As it moves more to the center, regions to the north - like the Puget Sound - will shift into its place, Jones said.

  "The climate of that area today is almost identical to the Willamette Valley in the 1960s," he said. "And because it has Seattle nearby, it will be a major market."

  Of course, not all winemakers will benefit from climate change: For example, California's San Joaquin and Napa valleys, which are already hot, may end up with lower-quality grapes and desiccated vines, Ashenfelter and Jones said.

  Similarly, growers in Western Oregon who have found ideal temperatures at the top of a slope may also face degraded conditions and need to change the placement of their vineyards to maintain quality, Jones said.

  As for grape growers east of the Cascade range, the likely effects of climate change are still unclear, he said.

  Higher temperatures could hypothetically improve grape production there as well, but they may also reduce snowpacks and induce earlier runoff, which would hurt irrigation, Jones said.

  Warmer winters could also impact Eastern Washington's important tree fruit industry, if the temperature does not stay low enough to maintain the trees' winter freeze requirements, he said.

  The overall impact climate change will have on rainfall is unknown: There is no consensus as to whether the West will experience more rain or less, Ashenfelter and Jones said.

  "Precipitation is a hard one," said Jones. "We don't have a very clear picture, other than that we will have variability."