Cirrus clouds may not be as pretty in appearance as some other types of clouds, however they are a very commonly occurring type of cloud. These clouds appear as wispy streaks in the sky, like a white or grey smear of paint.
As with many types of clouds, cirrus clouds are named based on how they look. The word “cirrus” comes from a Latin word meaning “curl”, and if you look at a cirrus cloud, you can see how it might resemble a lock of curly hair.
Where are cirrus clouds found?
A cirrus cloud is a high-altitude cloud, occurring at 20,000 feet or higher. Cirrus clouds have actually been spotted as well! In addition to forming on Earth, cirrus clouds can form on planets like Mars, Saturn, Jupiter, Neptune and Uranus! Although a cirrus clouds appears to be very flat and wispy, the thickness of a cirrus cloud is actually about 1.5 km!
How do cirrus clouds form?
Cirrus clouds are formed at very high altitude. When air masses reach these heights, the temperature drops drastically. These cold temperatures cause the moisture in the air masses to condense and actually freeze into ice crystals. This occurs above 8000m. Masses of ice crystals are visible to the human eye as a cirrus cloud. Because there is very little moisture at such high altitude, there are relatively few ice crystals, which gives these clouds their “thin” appearance.
What do cirrus clouds mean for the weather?
Cirrus clouds are almost always present at high altitudes, so small amounts of cirrus clouds do not have a big impact on the weather. However, forecasters usually take note when a large number of cirrus clouds form, as this can signify a change in the weather approaching. Usually, this will mean a storm is approaching. Cirrus clouds are usually present around the outer edges of a cyclone, so the storms systems that cirrus clouds bring can be severe.
Scientists have explored the idea that, because cirrus clouds are present across the Earth on a somewhat constant basis, they may have an impact on the Earth’s climate. What they have determined is that cirrus clouds actually help to warm the Earth, creating a natural greenhouse effect. However, cirrus clouds are generally regarded as not being a cause of global warming, because they do still allow the sun’s energy to escape through them.
Cirrus clouds themselves cannot produce precipitation, because they occur so high in the atmosphere. However, as moisture and air masses move and fall, the cirrus cloud may transform into other types of clouds at lower altitudes, which can then bring precipitation.
What gives a cirrus cloud its thin, wispy appearance?
The amount of moisture at high altitudes is relatively low, so there are relatively few ice crystals tat can be formed. This is why a cirrus cloud appears to be thin. Winds reach strong speeds at such high altitude and “blow” the collection of ice crystals outwards to create the “wispy” appearance of cirrus clouds.