How Climate Impacts Wine Grapes

June 3, 2019 // Article by: Zach Graff

While walking through your local grocery store for a bottle of wine, have you ever wondered why there isn’t more selection from New Jersey or New York compared to California? Why do they get all the shelf space? The main reason California gets all the love is because of their unique terrain and, in particular, the climate. California is the leading wine producer in the United States, with approximately 90% of the market share. New York ranks third just behind the evergreen state of Washington.

So what makes California’s more suitable for growing a wide variety of wine grapes relative to New Jersey or New York? One of the leading factors is the cool Pacific Ocean along with the chilly San Francisco Bay in very close proximity to the wine growing regions or AVA’s (American Vinicultural Areas). These waters are influential because it allows for cool, moist air to flow over the grapes, which helps equalize the warm, dry summers California exhibits. The average high temperature of the growing season (March through October in Napa Valley) is around 75°F, but a few stretches during the summer can exceed 100°F. This flip-flopping of hot and cool temperatures coupled with ample sunshine allows for grapes to flourish and mature well on the vine.

This climate is vastly different compared to New York. As many know, there is a lot more rainfall and cloudier weather during the summer here in the Northeast, which largely impacts the sugar content in the grapes. This sugar content is altered by sunshine, temperature and rainfall. For example, in warmer climates, the grapes can mature easier, allowing for higher sugar levels and a darker color. This high level of sugar in the grapes will lead to increased levels of alcohol and better overall flavor. While in cooler climates, the sugar content is much less which causes a higher level of acidity. This acidity can give the wine more of a tart taste, as well as a lower alcohol level. On the other hand, more rainfall allows for water to get trapped inside the actual grape itself, which dilutes the overall sugar in the grape. This causes a wrinkle in the winemaking process.

You may ask yourself, New York is the third largest producer of grapes in America, so the climate can’t be that bad, right? The main caveat is New York has a very difficult time growing bold, red varietals like Malbec and Sangiovese, because of its cooler, cloudier environment. On the other hand, New York’s climate is very appropriate for varietals like Riesling and Concord (the leading types of wine from NY) due to the cooler conditions. Overall, New York is not in same league as California, strictly based on the number of varietals grown. New York wine is not “worse” per say, but just different based on the weather and climate.

So next time you walk down the supermarket or liquor store aisle, remember this blog and appreciate the unique weather conditions that go into your favorite glass of cabernet sauvignon.