“Making contrails" WebApp Courtesy of the Cooperative Institute for Meteorological Satellite Studies (CIMSS), Copyright © 2008, 2011, 2013 by Tom Whittaker.
Check out the instructions for this simulation!
Adjust the environment by dragging the Big Red Dot around to set the temperature and humidity of the atmosphere. Click on the “Fly” button to start the plane moving. You can change the atmospheric conditions while the plane is flying!
You can change:
- The degree of supersaturation, which affects the density of the contrail (or how thick the contrail is)
- The relative humidity, which affects the rate of dissipation of the contrail (or how long it takes the contrail to disappear or dissolve)
- The wind speed by adjusting the temperature, which affects the rate of spreading of the contrail
Wondering what contrails are and how they form? Continue reading!
Contrails form when water vapor from an airplane’s exhaust condenses and freezes, forming clouds made of ice crystals. Knowing this, can you guess what the word “contrail” is short for? “Contrail” is short for “condensation trail”!
While it is easy to imagine that contrails are streams of pollution coming out of airplanes as they cross the sky, they are mostly ice crystals. Water vapor is already present in the atmosphere, but when the extra vapor from the airplane exhaust saturates already moist air, the water condenses and freezes into tiny ice crystals.
For contrails to form, it has to be really, really cold! Most commercial jets fly at 26,000 feet or higher. It’s super chilly that high into our atmosphere. Contrails form at these high altitudes because it is cold enough for water vapor to condense and freeze into ice.
On a clear day, the sun’s rays freely travel to Earth’s surface. We can see contrails because, when sunlight runs into the contrail, it is reflected by the ice crystals within them, making the cloud visible against the sky.
Scientists study contrails because, like naturally occurring clouds, they may contribute to a warming or cooling effect in Earth’s atmosphere.
In this simulation, you can create your own contrails!