LA MORRA, Italy — On a road winding through the heart of Barolo country, Michele Reverdito pulled his car over and stepped onto a sloping and sickly vineyard.

“Look at the wilting leaves and how small and shriveled the grapes are,” he said, holding a sad bunch of nebbiolo grapes in his hand on yet another hot August day.

The 48-year-old winemaker explained that unlike his own nearby vines, which were old, with deep roots, these vines were unable to tap the earth’s underground reserves of water, leaving grapes vulnerable to this year’s drought and brutal summer sun.

“Nebbiolo means ‘the wine of the fog’ because you picked the grapes in November,” he said. “Now we pick in September! The world is changing.”