THE CORIOLIS EFFECT

Lake Michigan Diary 98

The fog comes/on little cat feet./ It sits looking/ over harbor and city/ on silent haunches/ and then moves on.

That’s what Carl Sandberg wrote, and in my poetical twenties, I would read it and say, a-doy-doy, Carl, no it doesn’t. That was some poetical bullshit, I kept thinking. Because I was looking at San Francisco fog, no catfeet involved.

And lately? the weather report: heat for several days, but at an early part of the summer when the flowering Catalpa trees shed their flowers so it looks like Chicago brushed the remnants of a sloppy bucket of popcorn eaten at a stressful showing of “28 Years Later” off its laps and waits for the cleanup crew, and the great lake water is still relatively chilly. To repeat, the phenomenon of temperature over a great sweetwater lake is that it makes the land at the edge of the inland sea warmer in the chill of winter, and cooler in the heat of summer. The radio weather report, “Ninety-eight degrees in Chicago; cooler by the lake.”

Everybody thinks Mark Twain said that the coldest winter he ever experienced was a summer in San Francisco, and though the sentiment is true, somebody else said it, and then Twain spun it by saying “The coldest winter I ever experienced was last summer in Paris,” which is fancier. I lived in San Francisco for sixteen years, and one of the reasons the misquoted Mark Twain is because of the Coriolis Effect.

In the Bay Area, the marine layer is particularly cold and foggy due to coastal upwelling.

Coastal upwelling is the process by which the strong and persistent northwesterly winds bring deep and cold water to the surface at the coast. How they do that? With the aid of the earth’s rotation, when surface water flows along the coast pushed by the winds, the Coriolis effect then deflects the flow to the right in the Northern Hemisphere, which around that coast happens to be offshore. The displaced coastal water is then replaced by water from depth. Once this deep water reaches the surface, it cools the air, too, leading to the formation of fog as water vapor condenses into droplets because colder air can “hold” less water than warm air.

This is why hurricanes, draining bathwater, and the groinal biz of the gyrating men of Thunder Down Under swing in the opposite direction of bathwater, hurricanes, and groinal biz of the gyrating Thunder Down Under men in Las Vegas. SCIENCE

Hot air by nature only rises, and that is why God invented the Albuquerque Hot Air Balloon Festival. Have you ever heard of an undersea hot air balloon festival? Other than those Godzilla movies? If I had a nickel for every time Godzilla was killed by air bubbles, I would have two nickels, but that is a lot of nickels considering it has been established that Godzilla can be killed by air bubbles.

Can you tell I’ve been struggling with this f-ing diary entry? I’m trying to explain FOG ON LAKE MICHIGAN TODAY and somehow, I’ve strayed.

Anyhoo, The Coriolis Effect grabs San Francisco’s hot air and sends it into the Central Valley. A day or three of heat in San Francisco can only result in chilly clammy foggy vengeance, over and over. But September is nice there!

Meanwhile, a break in the heat caused a cool fog to hover over Lake Michigan today, and it didn’t burn off, as it does in San Francisco. It crept in on those little cat feet, because Carl Sandberg was born in Illinois and Lake Michigan Chicago fog is the only fog Carl Sandberg knew, experientially. It crept in and stayed. I was going to go kayaking, but then I would never have been heard from again. When I lived in San Francisco and saw that San Francisco fog, I thought, that’s not cat’s feet, because it wasn’t.

Now I understand fog as cat’s feet, even though never mind. Time to rehabilitate the poetry of Carl Sandburg. On the subject of grass, he was absolutely and awfully correct.