describe in few words about its climate?
They face severe cyclones.
Bay of Bengal
From January to October, the current is northward flowing, and the clockwise circulation pattern is called the "East Indian Current". The Bay of Bengal monsoon moves in a northwest direction striking the Nicobar Islands, and the Andaman Islands first end of May, then coast of Mainland India by end of June.

The remainder of the year, the counterclockwise current is southwestward flowing, and the circulation pattern is called the East Indian Winter Jet. September and December see very active weather, season varsha (or monsoon), in the Bay of Bengal producing severe cyclones which affect eastern India. Several efforts have been initiated to cope with storm surge.
where do cyclones occur in the southern hemisphere They generally form on a regular basis between the African coast and the middle of the South Pacific. what is "tropical cyclone basins"? They are divided into seven basins. These include the "North Atlantic Ocean", the eastern and western parts of the "North Pacific Ocean", the southwestern “Pacific Ocean", the southwestern and southeastern "Indian Ocean", and the northern "Indian Ocean" i.e. "Arabian Sea" and "Bay of Bengal". from where did the last mention region get its name? It gets its name from the historical Bengal region. how is the water quality of the bay? The water is polluted with sewage-borne pathogens and organic load; solid waste/marine litter; increasing nutrient inputs; oil pollution; persistent organic pollutants and persistent toxic substances; sedimentation; and heavy metals.
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Bay of Bengal [SEP] Oceanographic climate
From January to October, the current is northward flowing, and the clockwise circulation pattern is called the "East Indian Current". The Bay of Bengal monsoon moves in a northwest direction striking the Nicobar Islands, and the Andaman Islands first end of May, then coast of Mainland India by end of June. The remainder of the year, the counterclockwise current is southwestward flowing, and the circulation pattern is called the East Indian Winter Jet. September and December see very active weather, season varsha (or monsoon), in the Bay of Bengal producing severe cyclones which affect eastern India. Several efforts have been initiated to cope with storm surge.