Formation of :
(i) Sub- Polar high pressure belt : This zone experiences extreme cold throughout the year. As a result, the air ** chilled under the extreme cold that prevails over the poles, and this contributes to the steady high pressure experienced here. Polar winds *** from the Polar high pressure belts to the sub-polar low pressure belts. They are colder and stronger. They are also called Easterly winds.
(ii) Sub-Polar low pressure belt : As this zone is close to the Pole, the air is colder here. Though the cold air *** close to the Earth, the air is thrown up due to the rotation of the Earth. As a result, low pressure is experienced all along the region.
