Monsoon, Madagascar coast & Mascarenas High

The south-west monsoon travels thousands of kilometres from its place of origin off the Madagascar coast to Somalia from where it gets deflected to India to its retreat to Tibet in September and its final dissipation in Madagascar again -- a journey transcending continents, cultures and different climates.

1. The monsoon is born due to a high pressure area called the Mascarenas High.


2. The moisture laden currents then travel northwards to the African country of Somalia


3. From Somalia a jet stream formed in the month of May brings monsoon from Somalia to India.


4. Met officials explained the reason why India attracts the south-west monsoon from Madagascar:


5. The land in Indian subcontinent heats up in the month of May in summers but the ocean surrounding it does not heat up as fast as the land.


6. The hot air over the land mass rises creating a low pressure area.


7. The air from the high pressure area rushes to fill the void created by low pressure.


8. The jet stream brings moisture laden winds from high pressure area to India, hitting from south-west direction. That's why the monsoon is called `south-west monsoon'.


9. This south-west monsoon enters India through two areas


10. -- winds that gather moisture over the Arabian Sea lash the Western Ghats


11. ---those collecting moisture over the Bay of Bengal hit north-eastern states.


12. This further brings rain to West Bengal and Bihar. Both the streams merge over Central India to power the monsoon towards UP, Delhi and Jammu.


13. However, by this time the winds lose most of their moisture, hence northern states receive less rain than coastal areas. The last place to be hit by monsoon in India is west Rajasthan.


14. The monsoon starts withdrawing from the month of September. As temperature starts dropping in September, a high pressure area gets formed over Tibet, known as Tibetan High.


15. The anti-cyclone movement over this area pushes the winds coming from Bay of Bengal to assume an easterly direction, creating an easterly tropical jet which takes the winds back to the coast of Madagascar where it finally sinks into Mascarenas High the place of its inception.

The entire cycle of formation and departure is going on for thousands of years

http://timesofindia.indiatimes.com/Lucknow/Monsoon-in-UP-delayed-by-a-week/articleshow/4664396.cms