MONSOON?

The word "monsoon" comes from an Arab word means "season". It has to do with a type of climate in which winds blows from the sea to land ( onshore ) during the warm season, and from land to sea ( offshore ) during the cool season. The warm season of onshore winds is often very rainy, while the cool season of offshore winds may be dry.

What cause this seasonal change in winds and rainfall ? It is due to the fact that large continents or land masses heat and cool more rapidly than the surrounding oceans. Central and Southern Asia grow warm rapidly in the spring, and during the summer they are much warmer than the Indian Ocean on the South, or the Pacific Ocean on the east.

The warmer temperatures inland create lower atmospheric pressure, and therefore  the wind blows inland from the surrounding seas. This is the onshore or summer monsoon.

In the autumn, interior Asia cools rapidly and during the winter it has much lower temperatures than the surrounding  oceans. These lower temperatures create high atmospheric pressure, and therefore the winter monsoon winds blow outward from the dry interior regions toward the sea.