Question

Explain the formation of sub-tropical high-pressure belts and sub-polar low-pressure belts. Identify the planetary wind blowing in between these pressure belts.

Answer 1

Hint: On the surface of the earth, there are seven pressure belts. They are Equatorial Low, subtropical areas, dual sub-subpolar subtropical, and dual polar subtropical areas.

Complete Answer: The hot air that rises from the equator under pressure cools slowly and under the sides of the hot spot due to the rotation of the earth. In a low-pressure belt, although the cold air stays close to the ground, the air is blown high due to the earth's rotation. As a result, low pressure is experienced throughout the subpolar region. Westerlies on the other hand have a different phenomenon. This is due to the circular shape of the earth and also because different parts of the earth are heated unevenly. The Equatorial region receives high temperatures throughout the year. Warm air is lighter due to which the Equator air rises, which creates a lower pressure. In poles the heavy cold air causes high pressure to form. It is also because of the rotation of the earth. In the Subpolar region near 60 ° to 65 ° North and South of the Equator, the rotation of the earth accelerates the air toward the Equator, which in turn creates a low-pressure band in the area. From Polar High-Pressure belt to Sub Polar Low-Pressure belt, the deflection seems to be huge. This gives an impression that winds are blowing from east to west and therefore are called Polar Easterlies. Such types of winds that are formed by the pressure belts are called Global winds or Primary Winds or Planetary winds.

Note: Apart from the Equatorial low, some winds form two parallel pairs in the Northern and Southern Hemisphere. There is a pattern of some of the highest and most pressing bands in the world.