Climate change and wine grapes: Go, stay or change?

On a hot afternoon in California wine country, the sun can do more than warm a vineyard. It can scorch it. When temperatures climb above 100°F, grape clusters can heat to nearly 140° in direct sunlight. The berries shrivel. Their color compounds break down. Yields drop. And for growers who have invested millions in land and vines expected to produce for decades, a single brutal heat wave can ripple through the balance sheet for years.