Creek Running North

In summer, wind comes down the Pacific coast from Alaska. It pushes near-shore waters before it. They do not move in a straight line. Blow on a bowl of soup to cool it, and eddies will circle back to the left and right. In the bowl of the Pacific, land lies to the left, so no eddy forms there. Surface waters skitter offshore, at near-right angles to the northwest wind.

When the water heads west, more must come to replace it. A current comes up from the depths, ten or fifteen degrees colder than the water it replaces. At Stinson Beach, callow August tourists from the east run gleefully into the surf, shriek, and run back looking ghastly pale. They shiver in blankets and drink hot tea. 

From the depths, the upwelling brings crab larvae and copepods, free-floating marine algae, krill and other drifters. Fish eat them, and larger fish eat them in turn. This wind off Alaska feeds whales and seals. Shut it down — as happened this summer, for a time — and the food chain atrophies.

We along the California coast walk out in the morning, our world shaped by the whale wind. Moist wind meets cold, benthonic brine, and fog congeals from the summer air.

There are as many kinds of fog here as there are whales off the Farallones.

There is the creeping kind, the kind that has no boundaries, that wafts in stealthily until you suddenly notice that you cannot see fifty yards in any direction, and the sun is a faint bright dazzle above.

There is overcast, the fog that hangs five hundred feet above sea level, or two thousand, an obvious, sharp ceiling above the world. This fog looks much like a Great Lakes high summer stratus, except that it’s low enough to remove the peaks of hills, the top few floors of tall buildings. The towers of the Golden Gate furrow this fog, gray eddies twisting around orange steel.

There is the Glacier, a formidable wall of white a half mile high hanging ominously off shore, or sealing the westward neighborhoods of San Francisco in near-permanent gloom. From a mile off, or two, the Glacier seems placid. Venture toward the front and you will be buffeted. Where Glacier meets hilly land chaos thrives. You can drive north off the Golden Gate Bridge and watch rivers of thick fog flowing eastward down the drainages of the Marin Headlands, faster than any white water river. Every so often a spot near the ground will brighten, and then an eighteen-wheeler’s headlights will emerge from the torrent. By the time the back end is visible, the cab will have gone into the next river of fog. Hold tight to the wheel as you enter, for the cross-winds will push you up against the guardrail and down into Sausalito.

There are the tongues. These are the oddest fogs of all, and the most relentless. Our old place in Richmond attracted them: a band of thick fog a half-mile wide originating far out to sea, on an otherwise clear day. Three days out of five, that half-mile wide tongue would reach out from its home beyond the Farallones, beeline for the Golden Gate, slip under the bridge without touching the sides, execute a perfect turn at Alcatraz, and reach fifteen miles northeast to land in my vegetable garden. It rarely reached a mile inland from our yard. It rarely landed anywhere else. During our four years in Richmond I never had a ripe tomato before September, when the upwelling ceased, the water warmed, and the fog retreated off the Cordell Banks.