Fog Types Essay, Research Paper
1. There are five types of fog to be found. There is radiation fog which is the cooling of air to dew point by longwave radiation loss and is considered to be a diabatic process (involving the addition of, or removal of heat). This fog develops when the loss of longwave radiation during the night causes cooling to the dew point. This is most likely to occur on cloudless nights. Another type of fog is advection fog that is the cooling of air to dew point as it passes over cool surfaces. This fog is also a diabatic process and is formed when moist, warm air moves horizontally over a cooler surface than that of the air. This then transfers heat downward causing fog to form as it cools diabatically. Upslope fog is the cooling of air as it flows up slope, expanding and cooling as it moves upward. This process is adiabatic in which no heat is added or removed. We also have precipitation fog that increases the water vapor content of the surrounding air by evaporation from falling droplets. This is an adiabatic process. The last type of fog that we are familiar with is steam fog. This is the fog that occurs when you exhale on a cold winter day. This is fog that mixes warm, moist air with that of the surrounding cold air and is also considered to be an adiabatic process.
2. We have three major categories of clouds in meteorology consisting of low, middle, and high clouds. With high clouds we have the subcategories known as cirrus, cirrostratus, and cirrocumulus. Cirrus is a cloud that is entirely made up of ice crystals. Cirrostratus clouds are also composed entirely of ice crystals, but they tend to have less crystals. These clouds are known to form what is called the halo effect, a circular arc around the sun or moon that is formed by the bending of light as it passes through the ice crystals. Cirrocumulus clouds are the prettiest of all clouds for they arrange themselves in nice, long rows of individualized puffy type clouds. With middle clouds we have the subcategories known as altostratus and altocumulus. Altostratus clouds are the middle-level counterparts to the cirrostratus clouds. These, however, are more extensive and composed primarily of liquid water. Altocumulus clouds are layered clouds that form long bands of puffy clouds that are arranged in a row. These are often gray and usually contain darker spots. With low clouds we have the subcategories known as stratus, stratocumulus, and nimbostratus. Stratus clouds are layered clouds that form when large areas of stable air are lifted. Stratocumulus clouds are lower layered clouds that have some vertical development. Nimbostratus clouds are also lower layered clouds, but they are know to have a lower liquidity and weaker updrafts.