我深入探究了葡萄酒收藏界杂志中关于小气候的内容，这种概念在葡萄栽培区（AVA）中扮演着重要角色。作为加利福尼亚索诺玛山Trombetta Family Wines和Pfendler Vineyards的酿酒师，以及Petaluma Gap Winegrowers Alliance的一员，Erica Stancliff将小气候定义为“与周边地区具有独特气候差异的一小部分地区”。这些环境微妙的变化可能只影响几英亩，也可能跨越几平方英里。
影响小气候的因素包括与水体接近程度、土壤类型、地理特征、海拔和高度以及温度和湿度。即使是在一个葡萄园内，这些特征也会有所不同。“这不仅是酿酒师关于成熟度收获决定的重要考虑因素，而且这也是使一些小型酿酒区和葡萄园如此独特的原因，”Stancliff说。
Matt Dils, a winemaker in Santa Barbara, California, has a profound understanding of how small climate variations affect different regions within his AVA. Just like in Sonoma County, Dils says the biggest deciding factor is the distance from the ocean. Nearby vineyards feel the cold ocean air and fog.
In these two AVAs, a series of hills, valleys and plateaus make small climates even more nuanced. All these factors determine whether grapevines are exposed to marine influences or not. For example, fog settles in valleys creating cooler microclimates. Vineyards above the fog line are exposed to more sunlight during the day with higher temperatures but may experience more extreme diurnal changes due to elevation.
These details decide which varieties grow best where. “We get what we call cool-climate sunlight,” Dils said about Sta Rita Hills.“It's very suitable for planting Pinot Noir, Chardonnay and Syrah.” The Ballard Canyon [AVA]......[has] warm days and colder nights on its limestone soils with sand and clay. Syrah and Bordeaux varieties grow best there.”
Moving east towards Happy Valley vineyards face more extreme diurnal changes that help maintain acidity for widely planted Bordeaux varieties.
“I hardly considered Los Alamos,” Dils added in comment on numerous sub-appellations within broader Santa Barbara County AVA each with unique environmental conditions.
Stancliff collaborates with several vineyards in Sonoma County where Pinot Noir is one of the most widely planted varieties. Grapes serve as case studies on how to break down wider AVAs into specific environmental conditions.
“In some areas like Russian River black skin will mature slightly faster than surrounding coastal areas resulting in different flavor characteristics and tannin maturity,” she said.“In Petaluma Gap because of long growing seasons you'll see developed tannins and large structures matching fresh acidity deep color mature fruit flavors.”
Wind plays an equally important role at Petaluma Gap AVA named after gaps between coastal mountains that collect cool sea breeze inland.[It] defines our microclimate," Stancliff said."Grape skins form thicker skins."
Thicker skins will produce more color singletons concentration flavors in wines made from grapes grown under such conditions.
"For everything we do in our cellar it's important to remember that wine is defined by thousands of moments related to life of grapevines – wind sun root depth plus human intervention," Dils said."Terroir is driven by countless such moments."
