Types of wind :-
Wind are generally three types
1. Planetary winds
2. Periodic winds
3. Local winds
We discuss about these three types of wind one by one
1. Planetary winds :-
• Winds which blow throughout the air from one latitude to the other in response to the latitudinal differences in air pressure, are called prevailing winds or planetary winds.• These winds blow over vast area of the continents and oceans.
• Winds for climate and human activities.
Types of planetary winds
(a) Trade winds :-
These winds blow from subtropical high pressure area ( 30° N and S) towards the equatorial low pressure belt and are extremely steady winds.
(b) westerlies :-
These winds blow from subtropical high pressure belts towards sub-polar low pressure belts.
2 periodic winds :-
The winds changing their direction periodically with change in season are called periodic winds.
Monsoons are the best example of large scale modification of the planetary wind system.
Types of periodic winds
Periodic winds are also classified in three type
(a) Monsoon winds :-
These are seasonal modification of the general planetary wind system.
(b) Land and Sea breezes :-
These affect only a narrow strip along the coast. During day time, and land gets more heat than the adjacent sea and develop low pressure ,the Sea being cool, develops a comparatively higher pressure. The warm air of the land being lighter ascends and it's place is taken by the cooler air coming from the Sea, which is called sea breeze. At the higher elevation, warm air gets cooled and moves towards the sea. Hence, sea breezes blow during day at the lower and moderate the weather of the coastal fringe. At night, rapid radiation makes the land cooler than the adjoining sea.
(c) Mountain and valley breezes :-
During day time, slope of the mountain is heated more than the valley floor. The air from the valley flows up the slope, and is called valley breeze.
3. Local winds :-
Local wind develop as a result of local differences in temperature and pressure.
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Science