Pressure Belts

Pressure Belts


In this video. We shall learn about the various pressure belts and wind patterns that have developed on Planet Earth While understanding the basic concepts behind the development of pressure belts we will not take into consideration the tilt of the axis and the influence of land water distribution equator divides the Globe into Southern hemisphere and Northern hemisphere and equatorial belt extend up to five degree North and five degrees south equatorial region receives nearly vertical rays of the sun and this heats of the air near the equator when temperature increases pressure decreases So along the equator we have low pressure and we call this region as equatorial low pressure belt The warm air starts rising up in the troposphere and as the warm air is rising the temperature drops after rising up to a certain point it stops rising upwards because it becomes Cooler and it is obstructed by tropopause So the air spreads out the air starts moving in the Southern and Northern direction as the air is moving it becomes denser and after a certain point it sinks down to the surface So at around 30 degrees north and south we have sinking air This sinking air is cool air, so it forms high pressure systems these regions are called as subtropical High-pressure belts Because these regions lie outside the tropical region and at the same time adjoining the tropical region the sinking air now moves towards North and south So along the equator the warm air rises Spreads out and cools and sinks down in this way it develops Convectional currents at the poles the sun rays are very much inclined So we have cold air that sinks These regions are known as polar highs in the Northern hemisphere the air moves towards the South and in the Southern hemisphere the air moves towards north At this point we have air coming from North and south So at this point the air converges and rises up These regions are known as sub polar lows So at 60-degree latitudes. We have low pressure system because we have rising air Along the equator the air is rising because of convection and At sub polar lows. We have rising air because of convergence this rising air also spreads out cools and sinks Same things happen in the Southern hemisphere on the surface of the Earth along the equator the winds move from high pressure regions to low pressure regions That is from subtropical highs to the equatorial low in the Northern and Southern hemisphere These winds bend to the right in the Northern hemisphere and the Southern hemisphere the winds bend to the left and this is described as coriolis effect The winds bend to the right and left in the Northern and Southern hemisphere respectively because the Earth is spherical in shape and the Earth rotates from West to east in the same way in between 30 and 60 degrees North and South the winds bends towards right and left in the Northern and Southern hemispheres respectively Even at the polar region the same phenomena can be seen