One of my favorite sessions at The 2014 Wine Bloggers Conference was Michael Larner's (Larner Vineyard & Winery) presentation on the Terrior of Santa Barbara County. Not only is Larner a winemaker, but also a trained geologist, so he was undoubtedly qualified to explain the geology, soil, and climate of Santa Barbara County.
He started by describing how the county was formed, specifically the land actually moved up from what is now San Diego. Then it was covered by deep marine sediment that moved east from the ocean. Wish I could locate his video that shows the movement of land. The final position created two significant geological results. First, a small notch of land sticks out into the ocean. Cold water from the north circles through on one side and warm water from the south circles around the other. The result is fog; daily fog. Second, instead of running north-south, the two major mountain ranges run east-west, creating lanes for the fog to move into the valleys. This fog helps generate a larger diurnal shift - allowing the grapes to mature over a longer period of time.
Larner then spoke about the five appellations within Santa Barbara County as well as the proposed Los Olivos District. The Santa Maria AVA is the northern most AVA and was established in 1981. This region receives the most rainfall, has sandy to clay soils, and is close to the ocean which provides cooling from winds and fog. The sandy soils in Santa Maria (from deep sea debris pushed west from moving plates) explains why Bien Nacido Vineyards could plant its original vines on their own rootstock. Chardonnay dominates the area for whites; whereas Pinot Noir & Syrah dominate for reds. 
The Santa Ynez Valley AVA was established 1983 and has a Mediterranean climate but with distinct differences from east->west. This is why the SYV is sub-divided into three smaller AVA's plus the Los Olivos District. The Sta. Rita Hills AVA was established 2001 and is the closest to the ocean; thus also the coolest within SYV. Chardonnay and Pinot Noir are the favored grapes with many popular wineries located in the Lompoc Guetto. For those questioning the spelling of the AVA, Chile's Santa Rita wine empire had an issue with the AVA's name and politely requested a name change. 
Moving east, the Ballard Canyon AVA was pushed through in 2013 by Mr. Larner. The area has more diurnal shift than the western border and here Syrah dominates (over ½ of the vineyards planted are in Syrah) with GSM grapes as well as some Cabernet Franc. The AVA can be divided in half with the bottom portion composed of chalky soils and the northern area more limestone. The proposed Los Olivos District AVA is adjacent to the Ballard Canyon's eastern border and is home to Sauvignon Blanc and Cabernet Franc. the district's eastern border is, itself, adjacent to the most eastern and warmest AVA, Happy Canyon. This AVA was created in 2009 and can count on summer temperatures in the mid 90's. Here, Bordeaux grapes flourish in the warm temps and red and yellow serpentine soils.Looking forward to my next visit to Santa Barbara County. Click here to read about our bicycle tour of parts of the Ballard Canyon AVA from Buellton to Solvang. Cheers.
