Ship Tracks Off Coast of California – March 21st, 2009
The white streaks in the clouds off the coast of California are not condensation trails caused by airplanes, but rather “ship tracks” from passing ships.
Ship tracks form when water molecules gather around the exhaust ships release into the air. When enough water molecules collect there, a visible cloud is formed. Ship track clouds have a long, string-like form because they stretch over the long, narrow path where the exhaust particles have been blown by the wind.
The particles billowing from ships’ smokestacks enter the air above the eastern Pacific and create long, thin clouds that remain there for days.
This is because the air above the oceans generally suffers from less turbulence and convection than the air above land. The lower atmosphere is especially calm over the eastern Pacific in the summertime due to a layer of hot air that settles in 500 to 700 meters above that region of the ocean.
This effect creates a temperature inversion, placing a cap on the cooler air below, trapping pollutants and water vapor. While the inversion is responsible for the smog that reduces air quality in Los Angeles, it also allows for the formation of long lasting ship tracks.