West Coast Wind Blog: Star like fog pattern.

by Mike Godsey, mikeATiwindsurf.com

On the California coast we are used to seeing lots of weird fog phenomenon fog falls, razor-thin fog banks, hard-topped fog banks, fast appearing and disappearing fog masses.

But is rare to see a star like fog pattern in the satellite imagery of the clouds like we see out in the Pacific west of the San Francisco Bay Area today Nov. 4, 2019.

These trails were a mystery when they were first seen in 1965 in the TIROS V11 satellite imagery. But meteorologists quickly determined the cause of those tracks. The diesel exhaust from ships contains aerosol particulates that as condensation nuclei. More and more water molecules aggregate on these “seeds” until a visible cloud forms aloft trailing behind the ship. It also appears that sulfur dioxide from the ship’s exhaust makes the clouds more reflective and allows them to carry more water.

These ship trails are most best seen using near IR sensors on the satellite but sometimes, as in this image, the tracks are easily seen in visible imagery.

So why the star-like image? This area of the Pacific is an area where many shipping lanes cross and by chance today the trails made a star!

Of course, these days when opinions sometimes count more than facts I am sure that someone will see it as an omen that their favorite politician has been blessed by the heavens.

Here are images of many ship trails: ship tracks