Atmospheric Circulation and Weather Systems Test - 2

Air expands when heated and gets compressed when cooled. This results in variations in the atmospheric pressure. The result is that it causes the movement of air from high pressure to low pressure, setting the air in motion.

The force exerted by the rotation of the earth is known as the Coriolis force. 

The source region is an extensive region of the earth's surface where large masses of air having uniform temperature and humidity conditions originate. The best source regions for air masses are large flat areas where air can be stagnant long enough to take on the characteristics of the surface below. That's why the Siberian Plain is the correct option because it has a cold, large, and homogeneous mass of land.

Isobars are lines connecting places having equal pressure. 

A wind circulation around a low-pressure center is called a cyclone.

The weight of a column of air contained in a unit area from the mean sea level to the top of the atmosphere is called the atmospheric pressure.

This is one of the most devastating natural calamities. They are known as Cyclones in the Indian Ocean, Hurricanes in the Atlantic, Typhoons in the Western Pacific and South China Sea, and Willy-willies in Western Australia.

The formula for calculating air pressure at altitude is:

\(P = P_0 \times e^{-\frac{h}{H}}\)

where:

P = pressure at altitude

\(P_0\) = pressure at sea level (1013 mb)

e = Euler's number (2.71828)

h = altitude in meters

H = scale height (7,400 meters)

Given that the surface air pressure is 1,000 mb, we can use the formula above to calculate the air pressure at 1 km above the surface.

\(P = 1000 \times e^{-\frac{1000}{7400}}\)

P = 900 mb

In the Northern Hemisphere, this means that air is blown around low pressure in an anticlockwise direction and around high pressure in a clockwise direction.

There are four types of fronts: (a) Cold; (b) Warm; (c) Stationary; and (d) Occluded.