eastern region oil spill disaster contingency plan - Indian Coast Guard

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with passage of weather systems approaching from the west. These weather
systems are known as western Disturbances (WDs) and are noticed on synoptic
charts as low level cyclonic circulation’s Through, Low Pressure areas or
Depressions and induced systems there of. These systems given rainfall all along
their tracks followed by cold wave conditions at the rear of them Usually 2 to 3
Western Disturbances are expected in each of the winter months and affect the
weather of North Bay off West Bengal and Orissa Coast.
6. Currents Off Orissa, Andhra Pradesh and Tamil Nadu Coast: In the open
parts of Bay of Bengal surface water currents flow 15 to 30 deg to the right of
the prevailing winds. These currents get modified as they approach the East
Coast of India. A clock wise gradient usually found over West central and
Northwest Bay. The currents off north AP and Orissa / west Bengal Coasts are
directed NE wards and their speed is of the order of ¼ kt. In the East Central
bay the currents are mainly directed towards SSWly and the speed is about
1/4kt. South of 15 deg north, the mean surface current in the open sea is
directed towards the extreme parts of the South Bay. However near to the
remaining part of East Coast of India and east coast of Sri Lanka, the currents
are directed from N – NE to S-SW direction.
February
7. General. February is the last month of winter season. Basic conditions
remain the same as in January. The low level circulation over the central parts of
country during the month of February is 5 is anti cyclonic because of which dry
weather and low temperatures continue to prevail over most parts of land and
sea areas of the region. However equally weather accompanied by thunder
activity is often observed over the southern parts of South Bay and Southern
Andaman Sea. At times the weather over these parts deteriorate due to passage
of waves in eastern lies which move from east to west over the low latitudes,
giving rise to rainfall activity over coastal Tamil Nadu coastal Srilanka, South Bay
and South Andaman Sea. The general fine weather over the North Bay and
adjoining coastal areas is replaced at times, with passage of Western
Disturbances resulting in rainfall activity. The average surface winds are mainly
NE-ENE Ly / 10-15 Kts over Central Bay and South Bay and NW-N Ly /05-10 kts
over North Bay. Accordingly the state of sea is normally between calm to slight
visibility is generally good in afternoon and evening hours. However it may
reduce to 3000 M or less in morning haze / fog along the coast. The ocean