Crisscrossing Clouds

  • Released Tuesday, October 25th, 2011
  • Updated Wednesday, May 3rd, 2023 at 1:53PM
  • ID: 10839

Since 1965 scientists have observed unusual cloud lines that crisscross over the ocean in certain satellite images. Researchers initially speculated that aircraft, missiles, or even natural patterns of air circulation might have caused the oddly shaped clouds to form. But ultimately seafaring ships proved to be the culprits; specifically tiny particles found in the exhaust that billows from their smokestacks. The streaky clouds, called ship tracks, are found throughout the world's oceans. They form in the same manner as marine clouds, which are made of individual cloud droplets created when water condenses around sea salt and other airborne particles known as aerosols. Ship fumes, however, inject extra particles into the air that boost the overall number of particles and cause an abundance of small, more reflective cloud droplets to form. The result: lines of unusually bright and narrow clouds such as those seen in the video below.

Ship fumes create streaky white clouds visible from space.

Ship fumes create streaky white clouds visible from space.

A NASA data visualizer stitched together 298 cloud scenes collected by the Terra and Aqua satellites to create this video.

An unusually large number of ship tracks are visible in the clouds off the coast of France and Spain in this true-color satellite image.

An unusually large number of ship tracks are visible in the clouds off the coast of France and Spain in this true-color satellite image.

It's possible to see some ship tracks that aren't apparent in visible light by looking at the infrared.

It's possible to see some ship tracks that aren't apparent in visible light by looking at the infrared.

A NASA research aircraft captured this photograph of a container ship (right) and its ship track (center) off the coast of California.

A NASA research aircraft captured this photograph of a container ship (right) and its ship track (center) off the coast of California.

A schematic illustration shows how ship fumes increase the number of small particles in the atmosphere causing abnormally bright clouds.

A schematic illustration shows how ship fumes increase the number of small particles in the atmosphere causing abnormally bright clouds.

Credits

Please give credit for this item to:
NASA's Goddard Space Flight Center