This photograph shows many contrails in the sky near Sutherland, NE (November 2004).
Click on image for full size
Courtesy of Susan Gallagher
Contrails
The white streaks you see coming off high-flying jet airplanes are called contrails, which is short for condensation trail. Contrails are clouds that form when water vapor condenses and freezes around small particles (aerosols) that exist in aircraft exhaust. The water vapor comes from the air around the plane and the exhaust of the aircraft.
Some contrails evaporate quickly while others stay in the sky for a long time after the airplane is gone. These contrails can become human-made cirrus clouds. Contrails last longer when there is a greater amount of water in the air; they last until the water in the clouds evaporates.
There are three types of contrails: short-lived, persistent non-spreading, and persistent spreading.
The study of contrails addresses important scientific questions, as they are clouds whose formation is a direct result of human activities. A change in the amount of high-level cloudiness resulting from contrails may impact our climate. Contrails can be seen over virtually all parts of the world as white streaks across the sky. This image shows widespread contrails over the southeastern United States.
Shop Windows to the Universe Science Store!
Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our
online store.
You might also be interested in:
One process which transfers water from the ground back to the atmosphere is evaporation. Evaporation is when water passes from a liquid phase to a gas phase. Rates of evaporation of water depend on factors
...more
Cirrus (weather symbol - Ci) clouds are the most common of the High Cloud (5000-13000m) group. They are composed entirely of ice and consist of long, thin, wispy streamers. They are commonly known as
...more
As turboprop and jet aircraft climb or descend under certain atmospheric conditions, they can inadvertently "seed" mid-level clouds, causing narrow bands of snow or rain to develop and fall to
...more
Altocumulus clouds (weather symbol - Ac), are made primarily of liquid water and have a thickness of 1 km. They are part of the Middle Cloud group (2000-7000m up). They are grayish-white with one part
...more
Altostratus clouds (weather symbol - As) consist of water and some ice crystals. They belong to the Middle Cloud group (2000-7000m up). An altostratus cloud usually covers the whole sky and has a gray
...more
Cirrocumulus clouds (weather symbol - Cc) are composed primarily of ice crystals and belong to the High Cloud group (5000-13000m). They are small rounded puffs that usually appear in long rows. Cirrocumulus
...more
Cirrostratus (weather symbol - Cs) clouds consist almost entirely of ice crystals and belong to the High Cloud (5000-13000m) group. They are sheetlike thin clouds that usually cover the entire sky. The
...more
