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momo95
15th Jan 2018, 05:27
Good morning all, I'm having some difficulty trying to figure out what I initially thought was a rather simple concept.

Can someone please clarify the direction of air movement over India during winter and summer?

As far as I'm aware, in summer the ITCZ moves north, and so India should be covered by the SW trade winds south of the ITCZ that causes a SW monsoon to affect the country. Then in winter this jet moves south, causing India to be covered by the north of the ITCZ that blows NE trade winds ... leading to the NE monsoon.

However there are numerous questions in which the logic appears to be totally reversed. For example the questions in which the answer (or indeed the question itself) talks about an easterly jet during summer ... even though the next question will ask about the SW monsoon, also in summer. How is this contradiction? How do we have monsoons making their way from the SW (in line with the trade winds during that season) whilst simultaneously having an easterly jet, i.e. from the total opposite end?

Any help is greatly appreciated :)

Stanley Eevil
15th Jan 2018, 05:44
The monsoon is a low-level wind system. You may be confusing this with upper wind theory, where the upper wind in the vicinity of the ITCZ is often easterly.

cavok_flyer
15th Jan 2018, 16:29
I got my head around this by thinking where the air is rising at that time of the season. In N. Hemisphere summer, the continental landmass radiates more than the ocean, warm air mass rises, and pulls the moist air from the ocean onto land. In the winter, the other way (warm ocean, cold continental landmass) causing the dry monsoon.