Few factors affect the taste and quality of a wine more than climate. This broader term encompasses everything from altitude to weather. Given this season one of our episodes focuses on Malbecs from Mendoza, Argentina, we thought looking at how altitude affects wine was worthy of further examination.
Malbecs grown in Mendoza, Argentina’s largest wine region, thrive at some of the world’s highest elevations. In fact, Mendoza is the only major growing region with most vines planted above 3,000 feet in elevation. One vineyard, in the province of Salta, reaches 9,892 feet!
First, elevation affects temperature. Temperature falls 1.1° F for every 330ft gained in elevation. That means the average temperature of Mendoza’s 4,000-ft vineyards would be 13° F lower than in Bordeaux, based on altitude alone! Lower temperatures delay grape maturation, and they elevate acidity. You’d think this might result in tart, unripe grapes – but high-altitude vines also have more exposure to ultra-violet rays, which stimulates phenolic synthesis (different from sugar ripeness, this refers to structural ripeness of seeds, skins, and tannins) – and the grapes ripen anyway, but they stay fresh-tasting and don’t taste like grape jam. Additionally, night time and daytime temperatures tend to be very far apart. This temperature swings are known as “diurnal differences” and are responsible for that perfect balance of ripeness and freshness!
High-altitude vineyards are also generally mountain, or hillside vineyards. These vineyards tend to have much a more diverse soil make-up than the soils of the valley floor. The diverse soils provide an array of minerals and nutrients to the grapes, and ultimately the wine, resulting in a more varied and complex final product.
Photo of Mendoza, Argentina by Carlos Calise, courtesy of Wines of Argentina.