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The Piedmont region in northwest Italy produces renowned wines such as Barolo and Barbaresco. But weather extremes due to climate change are affecting the region's grapes, and that is forcing producers to find new ways to maintain their best vintages. NPR's Sylvia Poggioli has this report.
SYLVIA POGGIOLI, BYLINE: The rolling hills of the Langhe are home to Nebbiolo. The red takes its name from nebbia, the early morning fog that envelops these gentle slopes. The fourth-generation owner of a local winery is Angelo Gaja.
ANGELO GAJA: We own three wineries. And the historical one is Gaja, founded by my great-grandfather in 1859.
POGGIOLI: Some vintners are reluctant to talk about climate change. They fear that if they talk about its impact on what the French call terroir - the vines' particular geography, environment and how the soil and climate contribute to the grapes flavor. It could lessen the value of their wine. Not so at Gaja. As summers got warmer and devastating rains more common, this winery focused on making its vines more resilient to a changing climate.
The Sori San Lorenzo slope faces south, ideal for the slow-ripening Nebbiolo grape. But with prolonged heat waves, the grapes need more shade. So leaves are no longer stripped from the vine before harvest, says Angelo's daughter Gaia, a fifth-generation wine producer. And on these steep slopes, she stresses, it's important to prevent soil erosion from increasingly violent rainstorms that wash away vital nutrients.
GAIA GAJA: One of the first reaction was to be much more respectful of the soil and especially work better with the grass.
POGGIOLI: A few years ago, the Gajas took the bold step of planting various varieties of grasses along the paths separating the rows of vines. Giorgio Culasso is the vineyard master.
GIORGIO CULASSO: (Through translator) It was a revolution because our past tradition held that grass was the enemy of the vineyard because it was competing for nutrients in the soil.
POGGIOLI: So far, says Culasso, the results are positive - less soil erosion when it rains and moister soil during prolonged heatwaves. Up till the '70s and '80s, Nebbiolo was harvested in early November. By the early 2000s, hotter summers meant grapes ripened faster and were picked, on average, two months earlier. This year, after a perfect May, a heatwave struck in June with record temperatures at 107 degrees, followed fortunately by soothing rains in July. That made a late October harvest possible, with the prospect, the winery believes, of an excellent vintage. Gaia Gaja says this proves her family's vines are now more able to resist attacks from climate change.
G GAJA: You don't grow resilience if you you're not attacked. If your vine is perfectly always fertilized and is always perfectly sprayed with chemical product, it's a fantastic vine that has no stress but doesn't build any resilience. Resilience comes from attacks.
POGGIOLI: The biggest challenge, she says, is higher temperatures produce more sugar in the grapes, leading to higher alcohol levels that can alter the nature of the wine.
G GAJA: What is really in danger is the elegance of wines. You need a vine that made fully, fully, slowly, slowly ripe. And you need the grapes that they stay on the plant for very long time to really get a full complexity.
POGGIOLI: Like many wine producers in other parts of Europe, the Gaja Winery has started planting different grape varieties at higher, cooler altitudes - another sign that, along with the climate, Piedmont's wine-growing terroir is gradually changing. Sylvia Poggioli, NPR News, in the Langhe hills of Piedmont, Italy. Transcript provided by NPR, Copyright NPR.