Cirriform Names of Clouds
Cirriform clouds are also referred to as cirrus clouds. They are atmospheric clouds that look like thin and wispy strands. Often, Cirrus clouds are called a mare's tail because they resemble bunched up tufts. Cirrus means curl in Latin which is why it looks like curly hair in the atmosphere. Cirrus clouds are colored faint gray and white depending on their composition and they are found in the upper level of the troposphere, mostly composed of ice crystals because of the coldness at this height. Thin and wispy cirrus clouds indicate fair weather while heavy ones are signs of a coming storm.
Cirriform Clouds or Cirrus Clouds
Cirrus clouds have different thickness levels. Some are 330 feet thick while others can be as huge as 26,000 feet but the average thickness of these clouds is around 4,900 feet. They are mainly composed of ice crystal because of the extreme cold weather at the troposphere. Cirrus clouds have 30 ice crystals per liter on average, while the size of these ice crystals is .25 millimeters on the average. These clouds also vary in temperature, ranging from -20°C to -30°C.
Cirrus clouds are fun to watch because of their different shapes. What you don’t know is that the ice crystals in the clouds are responsible for the multiple shapes the cirriform clouds have. Cirrus clouds can look like solid or hollow columns, rosettes, plates and conglomerations. What determine the shapes of ice crystals are three things: air pressure, air temperature, and ice supersaturation. In cold regions like the Arctic and Antarctica, the ice crystals are a lot larger than normal and they can take the shape of plates, columns, and conglomerations.
Cirrus Clouds Used for Forecasting
When checking for atmospheric signals that will show signs of coming cyclones and storms in the area, weather forecasters look at cirrus clouds. Isolated cirrus clouds are insignificant but once the cloud is heavy and a larger number of cirrus clouds start to form, this means that there is an approaching weather disturbance in the area. This is usually a sign that bad weather is coming.
Cirrus castellanus cloud is among the cirriform names of clouds that show instability. When this cloud spreads and leads to the formation of cirrus radiates or cirrus fibrates, this means that a weather front is approaching. This weather front will still vary from warm and cold, and if it is a warm weather front, the cirrus clouds become cirrostratus clouds which tends to go lower and thicker. These are the fluffy clouds that you see on a bright and sunny day. However, if it is a cold weather front, cumulonimbus clouds will appear.
The veil of cirrus clouds is also used to forecast tropical cyclones but this is only applicable in the tropic region. If there are white cirrus clouds beginning to form and approaching the direction of the cyclone, this means that the cyclone will arrive in the area after 36 hours. Veil of cirrus clouds is also used to forecast the arrival of hurricanes.
Subtypes of Cirrus Clouds
In the above section, you have read about some cirriform names of clouds that seem rather unfamiliar. This is because cirrus clouds have different genera. The three main genera of cirriform clouds are cirrus clouds, cirrostratus clouds, and cirrocumulus clouds.
- If you’ve seen a cloud that forms a halo in the sky, this is called the cirriform cloud. They produce halos because they are entirely composed of ice crystals only.
- The next cirriform cloud would be the cirrocumulus clouds, which appear in patches and sheets. Often, cirrocumulus appears in rippling patterns with rows of clouds filled with spaces between them. When the patches of this type of clouds grow larger, it is a signal of instability in the high altitude signaling that bad weather is approaching. Cirrocumulus clouds don’t stay long in the sky and will change to normal cirrus clouds later on. This is due to the water vapor deposit in the ice crystals, which lower the cloud and disturb the upward convection.
- The last of the cirriform names of clouds would be the cirrostratus clouds. These clouds look like thin sheets in the sky. It is distinguishable among other clouds because the sun and moon can still be visible through the cloud. Cirrostratus clouds produce halos. They are formed when warm air is lifted up to the high altitude. Once the warm weather front arrives, the cirrostratus clouds go lower and then rain will start pouring within the day.
Contrails or Man-made Cirrus Clouds
Contrails are man-made cirrus clouds that are formed from a jet engine. Contrails are formed when the jet engine exhausts water vapor that condenses on the particles and freezes because of the cool surrounding air. You will know that this is a man-made cirrus cloud because of the visible trail it makes, which usually goes on and on. The jet engine’s exhaust also provides ice nuclei in the sky, which persistently produces cirrus clouds. Hence, air traffic seems to be a cause of increasing cirrus clouds in the atmosphere.
Cirrus Clouds and the Climate
The abundance of cirrus clouds in the sky has a net heating effect on the Earth’s atmosphere. Cirrus clouds cover 25% of the sky, absorbing infrared radiation and only reflect a marginal amount of sunlight. Cirrus clouds that are 330 feet thick only allow 9% sunlight to pass through while absorbing half of the infrared rays escaping the Earth’s atmosphere. Because of this, the temperature of the atmosphere gets warmer. In other words, cirrus clouds aid in the greenhouse effect, which contributes to global warming.
On the other hand, there are studies contradicting this process. One study shows that instead of trapping the heat in the atmosphere, the increase in temperature will increase the size of ice crystals, which in turn, can help balance out the infrared radiation in the atmosphere. This theory is supported by another study saying that if there is an increase in sea surface temperature then less cirrus clouds will form and infrared radiation will be able to escape the Earth’s atmosphere