A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. Clouds in Earth’s atmosphere are studied in the nephology or cloud physics branch of meteorology. Two processes, possibly acting together, can lead to air’s becoming saturated: cooling the air or adding water vapor to the air. There are many families, species, varieties and physical categories of clouds; but I don’t want to know all of that – I just enjoy looking at the clouds, just as kids do. I hope you’ll enjoy our gallery, and remember all those carefree days when you were kids.
Cumulus Clouds
At an altitude of about 2000 – 6000 feet, the Cumulus are one of the most common with flat bases and fluffy cotton wool cauliflower like tops that grow vertically. Cumulus are formed by a convection of air pushing a thermal of hot air upwards, as it rises it cools, expands and the water vapour condenses into tiny cloud droplets. If these clouds don’t have too much vertical growth, fair weather is ahead. However, these benign looking clouds can develop into the more ominous Congestus Cumulus, which can then grow on into the awesome Cumulonimbus.Cumulonimbus Clouds – the King of Clouds
This gigantic cloud is responsible for most types of extreme weather, such as thunder storms, heavy rain, hail, snow and tornadoes. These dense clouds can tower up to 10 miles in height, when a cumulonimbus reaches the troposphere the high winds flatten the top which creates an anvil shape. These clouds can been seen in groups or alone and are most common in tropical or temperate regions. Cumulonimbus can hold up to half a million tons of water. They can grow to form a Supercell Cloud which has the potential to be the most severe of thunderstorms – the photo below is of a Supercell, very scary!Stratocumulus Clouds
These grey lumpy clouds look like flattened cumulus and they appear in either horizontal layers of patches, rows or masses. They can produce limited drizzle and a little light rain, and can cover the whole sky for many hundreds of miles. These clouds are responsible for bringing a winter gloom that hangs around for days.Nimbostratus – the Rain Cloud
Covering the whole sky in a grey blanket, nimbostratus most commonly produce persistent moderate to heavy rain or snow.
Stratus Cloud – the Drizzly Cloud
When a large air mass cools at the same time, this creates a stratus Cloud. These clouds are a featureless grey mass, horizontal and the lowest forming. Stratus are fog or mist at ground level, the highest it can reach is 6,500 feet when it becomes a “cloudy day”.Altostratus – the Boring Cloud
When the Stratus clouds rise about 6500 feet it becomes the Altostratus. This flat mass belongs to the middle level of clouds, the thicker the cloud becomes the greyer it gets.Altocumulus Clouds
If there is a humid morning, you may see these grayish, puffy clouds which often precede a thunder storm. They can look like parallel bands or rolling masses.
Cirrocumulus Clouds
When you see these pretty puffy clouds sailing high, fair weather is forecast for tomorrow. These are seen in rows and form patterns like popcorn, cirrocumulus can also form a pattern termed “mackerel sky” due to the fish scale effect they produce. Cirrostratus can mean rain or snow within the next day.Cirrus Clouds
These are the highest clouds at 16,500 to 45,000 feet and are composed of tiny ice particles. They make wonderful wispy shapes due to the 100 – 150 mph fluctuating winds at that height. Cirrus mean fair weather ahead and are nicknamed “mare’s tails”.Contrails
Contrails are artificial clouds made from ice particles produced from the aerosols from aircraft exhaust. They are produced in very cold temperatures at -40 degrees and at high altitudes of 26,000 feet.Undulatus Asperatus Cloud
This surreal looking cloud is a new discovery, the first since 1951! This has been put forward for official classification by the founder of the Cloud Appreciation Society, Gavin Pretor-Pinney. It looks scary, but these clouds generally follow after a storm rather than become one. The wave affect comes from turbulent differing air masses pushing cloud into shapes like rough waves on the sea. If you are interested, you can read more about this special cloud at: A Guide to the Undulatus Asperatus.The UFO Cloud
This is an Altocumulus Lenticularis, a rare lens-shaped cloud that forms when moist air flows over mountains.
The Nacreous Cloud
This cloud occurs in the polar regions during winter at a very high altitude of 15,000 to 25,000 metres. They form at low temperatures and although beautiful they contribute to the destruction of the ozone layer. These clouds convert benign chlorine in the atmosphere into a destructive form and also by removing the nitrogen compounds that help prevent the chlorine becoming reactive. These clouds are becoming more common in the polar regions, particularly the Artic. Read more about this cloud formation here: A Guide to Rare Nacreous Clouds.Mammatus Clouds
Mammatus comes from the Latin, meaning “mammary” because of their bosomy shape! Mammatus clouds look like portents of scary weather, but they are actually harmless. Mammatus form of often on the underside of an anvil cumulonimbus cloud, after the storm has passed. The ice crystals at the top of the anvil start to sink as they become heavier than the surrounding air. The base of a cloud is flat because all moisture evaporates at that level, but the ice crystals they are still too large to melt, so they sink further – and this creates the mammatus pockets.
