_
.
SEA WATER
motion are varied, and among these the polar ice, the suu’s
heat, the trade winds and the rotation of the earth all
play their part. ,
This current is really only a portion of a system of currents
in continuous circulation in the Atlantic Ocean, a system
which cannot be said strictlÿ to begin or end anywhere.
,
We will however conne ourselves here to the North
Atlantic.
'
.
'
—
.
'
In the region just north of the equator the surface waters
'
are warmed by the erceheat of the tropical sun and their
'
salinity is raised by constant evaporation.
Upon these
,.
warm saline waters are continually blowing
per_
sistent north-easterly winds known as the “ North-east
Trades.”
Their action aids a natural tendency of the
surface waters to “move in an easterly direction
»
the north coast of the South 'AmeriCan cOntinent as the
_
North.Equatorial Drift, which ows on into the Caribbean
.
Sea and Gulf of Mexico.
Here the waters become piled
up so that the surface level is raised abovethat of the
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ocean water outside the islarids of the West Indies in the
Sargasso Sea. —Under such conditions the Water must
ow
somewhere in order to maintain its equilibrium.
Its only place of egress
through the Florida Straits and
here it issues as the mighty Gulf Stream, the actual current
_
"
through the straits being _50metimes known as the Florida
_
Stream.
heŒthe—GulfStream runs in a ’ortherly
.
direction along “the c0ast ofAmèrica ata speed
'
_
fourknotS (Plate 85).='
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…
'
w
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‘
—_
’Owing— to_Î the'r0tation of the earth there is a tendency
for any moving particle to be d‘eected to the right. ' This
,
'
action is felt by the Gulf Stream and it moves northWards
with an increasing trend t0wards the right or east, ‘so that
_
by the time it has reached latitude forty degrees north”
it- ;is owing due east across the Atlantic; «At this point
‘
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