eastern region oil spill disaster contingency plan - Indian Coast Guard

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surface currents over the Bay of Bengal of Bengal remain the same as that of
month of January.
8. Cyclonic Storms and Depressions. The Arabian sea is practically free
from tropical storms in this month. In Bay of Bengal they are very few. They
usually originate between latitude 5 deg to 9 deg North and west of longitude 92
deg East during the winter season. The frequency of formation of Cyclone and
Depression per year is 0.04. These systems initially move NW-Nly direction and
cross the Tamil Nadu or East Coast of Srilanka. However, on some occasions
after initial movement they may recurve and move in N-NNEly direction and
strike the Arakkan Coast.
March
9. General. The month of March, April and May constitute the premonsoon
season also called as Hot weather period. The main synoptic features
that are generally observed during these months, with a special reference to
coastal areas are given in the succeeding paragraphs.
10. Synoptic Features. During the month of March, a Heat low establishes
itself over the southern peninsula as a result of heating of the interior
landmasses. The heat low is shallow with no well-defined upper air circulation. It
is well marked only during the afternoon / evening hours.
11. Pressure Pattern. The pressure gradient over the entire country is
slack. The pressures are however slightly higher over Indian sea areas. The
center of high pressure cells, during the month lies at about 18 Deg North / 60
Deg East in the Arabian sea and 16 Deg North / 90 Deg East in the Bay of
Bengal.
12. Wind Discontinuity: In association with the high pressure cells over
Arabian sea of Bay of Bengal, a North –South wind discontinuity line develops
over the central parts of India with N/NWly winds on one side and S/SEly wind
on the other side. It normally joins with another discontinuity line is potential
area of thunderstorm / thunders activity.
13. Land and Sea Breeze. Since the pressure gradient over the country is
slack during March and sea breezes become pronounce in the coastal areas,
particularly in the late afternoon hours.
14. Thunder Storms. During the Hot Water Period extensive connective
activities occur causing thunderstorms hailstorms and dust storms, on days
having favorable synoptic situation. In general, thunder activity starts by March