The Santa Monica Mountains separate the basin of Los Angeles from the San Fernando Valley. And here in Topanga, west of Los Angeles basin, it separates the Pacific Ocean from the San Fernando Valley. Topanga Canyon is like a gouge through the mountains that connects the high valley to the sea.
I am not a climatologist or a geographer, so I don't know how all this stuff works, but what I do know from living here is that being a conduit between a high, hot, dry desert and a low, cool, damp coast makes for some interesting weather patterns.
The imbalance between the heat of the Valley and the cool of the coast creates a kind of suction or pull that draws the coastline fog up through our canyon. It's like this land is a living creature. It breathes - one day the Valley's lungs draw up the ocean moisture; then the next day it blows its sere breath down toward the sea. Or are there two creatures? Perhaps it's the ocean that wafts its damp breath toward the desert, and then sucks back the heat for warmth.
But whatever the cause - it's not uncommon for us to see a bank of fog rolling up the canyon, moving as if driven, moving with a purpose. And then it changes - rolls backward on itself, or dissolves into nothing.
This spring, on a recent morning I looked out to see the western mountains of Saddle Peak lit by the morning sun. Up at our house it was clear and bright, but down in the boulevard, it was socked in with thick fog that lay low and solid and thick, like a blanket of snow or cotton batting.
I went out to walk the dog, and within a half hour, the fog had dissipated - here it floats as thin and ethereal as a chiffon silk scarf, trailing through the eucalyptus trees across the canyon in the Fernwood neighborhood.
On another morning, the fog billowed and puffed, like the steam of a locomotive chugging up the canyon. As the train of vapor runs up-canyon, just below our neighborhood the creek forks, and the fog collides against the mesa that lies between the two creek branches, piling up, billowing and rising - sometimes to dissolve in the sun, or sometimes to engulf those of us in higher altitudes in its mist.
Three doves sit on a wire, as the fog rises around them.
It's where we live. All fleeting - wait half an hour and it will change. What a great place to live.