How is a marine layer formed?

Answer 1

A marine layer is a cool, moist, foggy layer of air that can be several hundred feet to as much as three thousand feet thick associated with offshore weather patterns. The marine layer is formed as cold ocean water such as is found on the Pacific Coast in California cools the air just above it. Warmer air above that layer acts like a seal, and keeps the air below it from mixing and dispersing. In the case of Southern and Central California, a steady west wind often brings the marine layer ashore overnight, blanketing coastal communities in a cool, thick advection fog. This can last until midday when the heat of the sun is frequently strong enough to break the inversion layer and dissipate the effects. In California, the marine layer is most common from spring through to fall. The colloquial term "June Gloom" is used by locals to refer to the persistent gray marine layer overcast that is typically prevalent during that month. Drizzle or light rain can also be associated with a particularly wet marine layer. I have copied this information from a blog I came across when I was trying to find out the same thing. Here is the link: www.justpleinair.com/blog/_archives/2007/6

Answer 2

A marine layer is formed when warm, moist air from the ocean moves over cooler coastal areas. As this air cools, its moisture condenses into fog or low clouds near the surface. The marine layer is common in coastal regions with temperature contrasts between the land and ocean.