Question

there is a seasonal shift in pressure belt

Answer 1

The earth resolves on its orbit round the sun in 365 days. The earth is inclined on its axis at an angle of 23.5 degrees. Thus, the relative position of the earth with the sun changes. In consequence, the position of all the pressure belts change with the northward and southward migration of the sun. At the time of summer solstice the sun is vertical over the tropic of cancer and therefore all the pressure belts except the northern polar high pressure belt shift northward. In the Northern Hemisphere, the equatorial low pressure belt prevails between 0 degree latitude and 10 degree N latitudes, the subtropical belt extends between 30 degree and 40 degree N latitudes. Thus, all the wind belts associated with the said pressure belts also shift northward. The sun becomes vertical over the equator at the time of autumnal equinox (23rd September) and hence all the pressure belts positions. After autumn equinox, there is southward migration of the sun, which becomes vertical over the tropic of Capricorn at the time of winter solstice (23rd December) and hence the pressure and wind belts shift southward except the southern polar high pressure belt. Thereafter, the sun again becomes vertical over the equator at the time of spring (vernal) equinox (21st march) and hence all the pressure and wind belts occupy their normal positions. Thus, there is shifting in the position of pressure and wind belts due to seasonal changes of position of the earth in relation to the sun. These seasonal changes in the relative positions of the pressure and wind belts influence the areas of the Mediterranean climate and the position of the westerlies which move northward in the summer season (June) and southward in the winter (December) season. The summer and winter monsoons and the complete reversal of wind direction are also the result of shift of wind and pressure belts. Both the trade and anti-trade winds are thus closely influenced by the shifts in pressure belts

Answer 2

The distribution of atmospheric pressure across the latitude is termed global horizontal pressure of distribution of pressure its features zontal character called pressure belt......