The Red Sea, the only enclosed coral sea in the world, is
a distinctive and unique
tropical sea - an unparalleled source of entertainment and
beauty. Running as a narrow strip between Africa and Arabia
for 1500 miles, the Red Sea joins at its southern tip the
Indian Ocean through the Strait of Bab-El-Mandab, while
at its northern head it branches into the twin gulfs of
Suez and Aqaba. Unlike the arid lands of desert and semi-desert
on either side, the Red Sea is framed with thousands of
untouched coral reefs, oases of teeming under-water life
basking into its shallow waters.
The Red Sea is characterized by its high salinity - a
consequence both of the hot climate and the absence of
any river adding fresh water to the sea. The surface sea
temperature ranges, according to the time of the year,
from approximately 20 to 26 degrees Celsius in the northern
part, and from 25 to 31 deg. C in the central and southern
parts. Clear skies, strong sunlight and the absence of
inflowing sediments contribute to excellent underwater
visibility, leading to the Red Sea waters being among
the clearest waters in the world.
The normal tides are small and occur on a semi-diurnal
(twice a day) basis, with the whole sea oscillating around
a nodal point approximately at the latitude of Port Sudan.
The Peak tides, at the northern and southern ends, are
of about half a meter, while in the center there is no
virtual daily tide. There are, however, throughout the
Red Sea, seasonal variations in water level over a longer
period, the mean water level in Summer being nearly a
meter lower than it in Winter.
The Seasonal tides, and the pattern of prevailing winds
and currents, are all influenced by the change between
summer and winter monsoons in the Indian Ocean. During
the summer northerly winds prevail through the whole Red
Sea, the main surface current generated by these winds
is to the south, and water is driven out of the Red Sea,
thus lowering its level. During winter the prevailing
winds are still northerly in the northern half, but in
the southern part are from the south, and these winds
generate a northerly current, thus bringing water back
into the Red Sea again.
