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ahead of warm or obstructed fronts, but as the front passes, these clouds bulk out to become nimbostratus clouds (which can produce rain or snow). Altocumulus clouds are generally associated with settled weather that will commonly appear with a white or grey shading depending on its features. Altocumulus clouds exist in patches of clouds commonly found as rounded clumps. Depending on which differing cloud is created, the formation process of altocumulus clouds could happen as a breakup in an altostratus cloud, the lifting of a warm air pocket cooled by gentle winds or turbulence or mountainous terrain creating different atmospheric waves. Due to altocumulus clouds found in settled weather, they rarely rain; even if they do, it will rarely reach the ground instead forming a wisp that is retracing it steps back to the clouds. Cirrus The highest (5,500 meters to about 12,200 meters) layer of clouds is known as the cirrus layer, and it is comprised of long stranded, hair-like clouds. They are primarily made of ice crystals as they are very high, so are whiter than any other

cloud. During the day, they will be whiter than any other clouds but during sunset or sunrise they will take onboard the colours of the sunset or sunrise. Cirrus clouds form naturally or with the assistance of humans: they form ahead of a warm from and indicate a change in the weather is coming and can develop from the trails left by airplanes. The cirrus layer has several different clouds found within itself: cirrus fibratus, this cloud consists of two parallel, thin stripes that will follow the direction of the wind; cirrus uncinus, when translated into English the word uncinus means hook and that is what it looks like as a cloud, or it can be known to be a ‘horse’s tail’; cirrus spissatus, is right at the end of the troposphere (10,000 meters) and is very; cirrus floccus, it is more ragged or cotton wool-like in patches than other cirrus family members or floccus members; and cirrus castellanus, more vertically developed than its neighbor (cirrus floccus) and the tops can look a tad more like turrets. Special Clouds Fog is when your visibility has decreased to below 1 kilometer (for weather forecasts it is usually 180 meters) whilst

mist is anything above 1 kilometer. On the other hand, is haze which is completely different and is the suspension of tiny, dry particles which are invisible to the naked eye but together, the particles can make the air look more opalescent. Other than the distances mist and fog are the same thing. Fog and mist are just an extremely low-lying cloud containing millions of water molecules and ice crystals, but fog and mist can only appear when the surface of the Earth is cool so that the warm air will cool close to the surface. Virga clouds are long, hair-like that will form when the rain from a cloud dissipates before it hits the ground. They come from the base of the cloud and when a sunrise or sunset is occurring, they have a golden tint to them which makes them look gorgeous. Although they are a sight, virga clouds can cause turbulence for plains due to the water vapor from the rain taking a lot of the moisture in that area (there is not a lot of water molecules except for clouds at that altitude). Some people may call virga clouds ‘ jellyfish’ clouds because the cloud is like the head of the jellyfish and the small lines coming from the head are like a jellyfish’s stingers. Even though contrails or condensation trails are created by

planes, they are a cloud! They will come in lines or be longer than wide and are just a tiny amount of water vapor. Water vapor is a biproduct of burning airplane fuel so due to the high altitude of 6,000 meters, the water vapor will rapidly freeze and stay petrified in the air. If the air is very dry, the water vapor will then further turn into a solid (sublimation) but otherwise it will just spread out a bit and create a fluffier cloud. Since contrails are not very dense, they shall not produce any rain (unless they merge with another cloud). Clouds, like many other features on earth, are very interesting and they have been split into multiple layers and further split into categories. Each category has its own unique features in the way that higher clouds are more ice crystals than water vapor. Not only are there different layers, but there are also clouds like contrails and virga clouds which are captivating as well. On a personal note, the clouds are a beautiful part of our world and I really enjoyed gazing at them outside of my window whilst making this.

18 | Geographical Magazine • Merchant Taylors’ School

2021/22 Edition | 19