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pressures over the Pacific every two
to seven years and enables an El
Niño condit ion to develop. Here's
how.
Under normal circumstances,
high pressure cells (columns of
warm light air) domín a te the
Pacific Occan. Together with the
ear th 's rotat ion, they c reate a
clockwise (in the Northern Hemi–
sphere) and counterclockwise (in
the Southern Hemisphere) move–
ment of ai r. This movement creates
the easterly (east to west) trade
winds along the equator.
One result of the easterl ies is
that the warm surface water of the
eastern Pacific is blown westward
making the western Pacific both
slightly higher and warmer than
the eastern Pacífic. In addítíon, thc Beach residences collapse, Santa Cruz, Cali fornia
movement of warm surface water
from east to west creates an upwell–
ing of nutríent- laden cold water in
the eastern Pacífic. This helps sup–
port the abundant supply of fish
and marine fowl that normall y
inhabi t the South American coastal
waters.
As the Pacific high pressure cells
begin to break down, for reasons
not yct known, low pressure cells
(columns of cool dense air) take
their place. This causes the easter–
lies to die down or even reverse
direction. With no wind to push the
su rface water to the west, and the
addition of a warm water equatorial
counter current (west to east), the
eastern Pacific's water level a nd
temperature begin to rise. This
drives away the fish and fowl in the
area. The end product is what is
known asan El Niño condition.
As El Niño develops, water tem–
peratures rise significantly. In sorne
areas of this most recent El N iño,
water temperatures increased by as
much as 15 degrees Fahrenheit.
This can be compared to a pan of
thíck soup on low boíl. As the tem–
perature begins to rise, bubbles
explode on the surface here a nd
there. Likewise, as the hot, mois–
ture-Iaden air of the eastern Pacific
heats up, it spawns violent storms
here and there.
Now add to the scenario that as
the low pressure cells develop in
the Pacific, they begin to attract
the jet streams toward the equator.
lt
is easy to see how s torms devel–
oping in the Pacific could be blown
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