Here is a short video I took of the Los Carneros District just south of Domaine Carneros looking south towards San Pablo Bay. Notice how flat it is - this allows the fog to roll in quite fast.
I am standing on the last hill. Back to my left (towards Napa) the topography is more hills, while to my right (toward Sonoma) the terrain stays relatively flat and lower. This contributes to the difference in flavors and structure in the wines from Napa Carneros and Sonoma Carneros.