If you don’t believe in climate change, ask a farmer.

Few farmers see the more immediate impact of warming temperatures than winemakers and vineyard managers across the country.

In normally cool-climate Oregon, the vineyards are warming. But just like the different terriors across the 150-mile long valley, the impact varies from vineyard to vineyard. But winemakers seem to agree something is happening.

“I don’t think it necessarily means warming for everyone at every time of the year,” said Alloro Vineyards winemaker Tom Fitzpatrick. “I think what we’re seeing is wide swings in the temperatures and weather during the ripening period, which is really an important period of time.

“So the last couple of years (2016-2017) were fairly warm and fairly early harvest in September," he said. "Then in 2018, things were a little bit more typical at harvest. We had a really dry and really warm summer. We were lucky to get these really cool temperatures, 60s and 70s, through early September for harvesting."

The state’s legislature ordered a climate assessment that concluded with a 160-page document. The report says that even if emissions are reduced, average temperatures will rise 3 to 7 degrees by 2050. That number may or may not seem significant, but the state’s leading crop, delicate and thin-skinned Pinot Noir grapes, does not do well in intense heat.

“I typically talk about global change instead of global warming,” said Youngberg Hill Winery and Inn owner and winemaker Wayne Bailey. “I think what we’re seeing is a lot more extremes. There is extreme rain in the Midwest, extremes in terms of cold and warm and extremes in terms of hurricanes. It’s all over.

"More specifically to growing, over the last four to five years, we’ve had consistent warmer temperatures. But I’ve been in agriculture all my life and know weather patterns go in 20-year cycles. I’m here to say in five to six, years we’re still going to have warmer and cool years. I’m going to suggest there are going to be more extremes instead of less extreme weather events because of global warming.”

Steve Lutz, owner/winemaker at Lenne Estate, agreed it’s all about the timing of the state’s hotter spells.

“We’ve been really fortunate,” he said. “This year, we had a huge cooldown at the end of August and beginning of September. We had 10 days of no sugar movement in the vineyard at all. My take is we have to be very careful how much fruit we drop (which allows remaining fruit to ripen better).”

Lutz’s point is cutting grapes aggressively, followed by a warmer fall harvest season, could substantially reduce a winery’s ability to reach normal production levels. More heat means more sugar in the grapes, which results in wines with a higher alcohol content while the industry is largely moving to lower alcohol wines.

One logical step might be the increased planting of varietals other than Pinot Noir. Tempranillo, gamay, syrah and even some cabernet have been planted in recent years.

“Don (Hagge) is way ahead of the curve as usual, and we’re already making estate tempranillo in the Chehalem Mountains AVA,” said Vidon winemaker David Bellows.

Hagge owns the boutique Vidon winery.

“Other people are only going to plan more similar grapes," Bellows said. "Tempranillo is a good illustration of how to cope because I can’t think of a more hot plains varietal. It has ripened here three years in a row and ripened just fine this year.”

All of the winemakers agreed there will be years of bigger wines — Pinot or different varieties.

Bellows said the 2018 crop went through higher temperatures than the 2017 crop.

“So the 2018 had more sugar than we would want, so we worked on more extraction, more body to balance off the alcohol," he said. "Those are the kind of things you have to do. We’re going to make a bigger, darker wine than last year. We hope more extraction will balance the alcohol.”

So will there be years where Oregon Pinot is closer to the mouth feel of pinots from California?

Bailey agreed.

“There will be years,” he said. “In 2012 and 2014, the wines were bigger, more robust, more red fruit. But consistently, I think not for the foreseeable future. We’re not growing on the valley floor where it’s hottest.”

Fitzpatrick takes a similar view.

“To me, a great pinot is a balance between a warm year and much cooler year, concentration density and roundness, very cool delivers aromatic complexity and more expression," he said. "To me, a great vintage is one where weather conditions are such you get both of those.”

All four winemakers agreed they’ve spent a career watching the weather.

With temperatures rising, watching the thermometer is fine, but more adjustments in winemaking will be necessary, as well.