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CURRENTS
Currents
run for six whole months, each way. If a vessel happens to be at the
northern extremity of this islands it is no great matter, for then it is
only carried to Cochin, on the coast of India, or thereabouts, about a 150
leagues distance, or to some of the islands on that coast. But if they
cannot make the islands of Ceylon, they are carried to Sumatra, a distance
of about 500 leagues; and if ill-luck has it that these currents carry
them away at the close of the monsoons, and before they make land
anywhere, they are caught in the other current, as often happens, they are
infallibly lost, as I have seen in a number of cases, when they were
expecting to make land every night, and were without water and provisions.
If the current carries them to the west, they are borne straight to the
Arabian coast, which is much further off than that of Sumatra, but most
often they are dead before they get there".
Francois Pyrard, Maldives,
1602 - 1607.
The
currents of the Maldives are notorious for their strength. For this
reasons early traders in the Indian Ocean were extremely cautious when in
the Maldives region. Many ships by-passed the Maldives to the North and
South when they had no reason to visit, others took on local pilots to
steer them through the maze of reefs and their treacherous currents.
The exposure of the
Maldives to the vast Indian Ocean ensures that an immense body of water is
constantly flowing across the plateau on which these Atolls are built.
Ocean currents are largely influenced by the direction of the trade winds
and are of great strength. Currents in the channels near Male' have been
recorded at 4 knots or more. Inside the Atoll, current speed are more
settled and leisurely dives are more than norm. Tidal currents, which flow
according to the height of the tide and the direction of the prevailing
winds, are said to be much weaker than oceanic currents, though they cause
velocity variations in the flow.
Early Arab navigators
studied the patterns of these oceanic and tidal currents to help them
determine their position. When in the vicinity of the Maldives they
observed changes in current direction and surface patterns as the ocean's
waters confronted the great underwater barriers of the Maldives
archipelago.
On the eastern side of
Male' Atoll, currents predominantly flow into the Atoll when the
North-East monsoon is firmly set and flow outside during the South-West
monsoon. The opposite applies to the western side of the Atoll. This is by
no means the rule, as changes in wind direction and tides can offset the
influence of the oceanic currents. If the winds ease off for a few days,
then currents are more likely to flow both in and out of the channels.
During the seasonal
transition months of April and November, when the wind direction and
oceanic currents are less predictable, current is more likely to be
influenced by the tides and similarly flow both in and out of the
channels.
At Atoll passages, current
streams can be quite irregular due to the islands, reefs and sandy shoals.
Most Dhoani captains show great skill in reading the direction of the
current and take great pride in their knowledge of the ocean. If you ask:
"Oi Othee Kon Thaakah" (which direction is the current going?), they will
usually wave their hand and say: "Mi Athah" (this way), or "Eh Athah"
(that way)
Usually they can tell the
current direction by the tiny wave patterns on the surface. If there is no
wind, the current forms ripples that bend around stationary objects, like
the reef, in the direction of flow. The captains can also tell current
direction by the shape of the ripples and the movement of the Dhoani. If
the current is flowing against the wind, then the surface appears more
choppy than if the current is flowing in the same direction as the wind.
If there is very little, or no current, and the captains don't know its
direction, they will usually guess one way or the other, otherwise lose
face. For this reason, it is always advisable for the dive master to enter
the water and check if in doubt. It is better to be sure, and dive on the
best point, than miss the point altogether.
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