Cyclones in Bay of Bengal

Each year cyclones form over the Bay of Bengal and Arabian Sea and affect various parts of India, Bangladesh and Myanmar. Many of these storms turn violent and cause great havoc, damage properties and life.

It appears that the number of cyclones over the Bay of Bengal is much greater than over the Arabian Sea. Three distinctive periods in a year can be identified for the occurrences of these storms and depressions in the Bay of Bengal and Arabian Sea. These periods are:

1. The pre-monsoon period in the months of April and May.
2. The monsoon season covering the months of June, July August and September.
3. The post-monsoon period in the months of October, November and December.

The period of January to March records very few storms – both over the Bay of Bengal and the Arabian Sea.

In the monsoon season the disturbances usually form in the north of Bay of Bengal and generally move in a north-westerly direction. The storms developing during this period are less severe, but contribute large rainfall over the coastal districts of Orissa, West Bengal and also inland areas of Bihar plateau and eastern Madhya Pradesh. On the other hand, the disturbances in the pre-monsoon seasons develop in different regions of the Bay of Bengal and move in various directions. The tracks of many of these disturbances undergo recurvature. In general these storms are violent and cause widespread damages over the coastal areas of Andhra Pradesh, northern Tamil Nadu, Orissa, West Bengal and sometimes coastal districts of Bangladesh and Arakan coast of Myanmar.

These tropical cyclones cause damages in three ways:

1. The storm surge with an abnormal rise of sea level resulting in inundation of the coastal area.
2. High velocity stormy winds that damage buildings and other structures.
3. Heavy rain that gives rise to flooding and water logging of vast area. This results in destruction of standing crops in the fields.