Katabatics wind, a word derived from the Greek word ‘katabaticos’, are high-density winds that blow downwards from a high elevation due to the force of gravity. These winds are, therefore, also known as ‘Fall Winds’.
Katabatc winds travel at a great speed, some even at a speed of a hurricane. But, in most cases, the speed is not so intense and it does not cause much damage. However, not all the winds that travel downwards are Katabatic winds.
Some of the other winds are Chinook, Foehn winds, and Bergwinds, in which the air that was earlier blown upwards comes down with dry and warm air.
Places where you can find katabatic winds are Adriatic, south California, and Japan and these winds are known as Bora, Santa Ana, and Oroshi respectively. One can also experience katabatic winds in New Zealand, known as ‘The Barber’, which is responsible bringing the cold air in the entire region of South Island.
These winds are usually cold because it forms from the elevated ice blocks found in Greenland and Antarctica. Since the wind that is formed in these icy regions is of high density, it is attracted to the ground due to the gravitational force. And when such winds reach valley regions, it can flow at the speed of an hurricane.
One of the most famous forms of katabatic winds is Mistral that is formed in Europe. In the southern area of France, Mistral flows down the Rhone valley, and the speed of this flow sometimes reaches above 80 miles per hour. This is usually found in early spring and winter.
However, some of the most dangerous katabatic winds flow in Antarctic region. The air first goes up the cliff and cools of at a very low temperature, causing the formation of very high-density winds. This wind them comes down at the speed of 200 miles per hour. This form of katabatic wind is one of the strongest winds found on this planet and is capable of destructing the entire region.
In parts of California, it has been found that right from the beginning of a nocturnal cooling period, air in valley floors can remain colder than that on the upper slopes, and that downward moving air caused by katabatic drainage cannot penetrate the denser air in the lowest part of the valley, and remains above it.
Reference: http://www.whatisguide.net/0128-katabatic-winds.html
