Distribution of air pressure belts is not equal every where. Daily and yearly changes occur in air pressure, due to factors such as the situation of the summer solstice and winter solstice of the sun, the difference in the nature of the land and the water. In the summer when the Sun is in the northern hemisphere, these belts shift from their average position towards 5° north, and in the winter, when the sun shines directly in the southern hemisphere, these belts shift from their average position to 5° southwards.

Their ideal condition is only on 21 March and 23 September, when the Sun is vertical on the equator. At the time of shift of air pressure belts, the equatorial linear belts get extended in the northern and southern hemisphere between 0° to 10° latitudes instead of 0° to 5° latitudes, according to the season. Similarly, the subtropical belts shift between 30° to 40° latitudes instead of 30° to 35° latitudes, while the sub – polar belt is found between 60° to 70° latitudes instead of 60° to 65° latitudes.

Due to the continental expansion in the polar regions, especially in the North Polar region, it has a greater effect as the polar belt becomes very narrow in summers here. In the southern polar region, due to narrowing of the land and ocean expansion, there is no special change found in them.