| El Nino
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According
to NOAA (National Oceanic and
Atmospheric Administration), El
Nino is described as the "disruption of the ocean-atmosphere system in the
tropical Pacific having important consequences for weather around the
globe". This involves the unusual
warm conditions that appear in
the coastal areas near Peru and
Ecuador, South America. Actually
El Nino is a term used to
describe the warm southward
current of the Pacific Ocean,
that appears every December of
the year. However, it's now
become more intense and severe
over the past years, especially
in the 1982 and 1983 season, and
once occurring, it affects the
climate for one year around the
globe. It's now happening every
3 to 7 years, including 1972,
1976, 1982/1983, 1987, 1991,
1994, 1997.
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El
Nino's disturbance to the
weather system is identified by
the reversal of the normal
weather conditions in the
eastern and western Pacific
caused by the sufficiently warm
and persistent ocean currents.
During this event, the trade
winds that usually blow from
east to west is collapsed and
even reversed to blow from west
to east, thus changing the climatic pattern of
the western Pacific and the
eastern Pacific. The western
Pacific that usually moist, warm
and high in rainfall is changing
to an arid and low rainfall
condition thus bringing droughts
to south-eastern Asia, India,
and southern Africa. While the
eastern Pacific that usually
arid, cold and low in rainfall
is reversed to a moist, warm and
high in rainfall, leading to
heavy rainfall in the areas.
Below
is a table explaining some
important pointers for El Nino:
| Impacts |
- Increase
of rainfall in the
eastern Pacific
- Arid
conditions causing
droughts and in
western Pacific:
increased risk of
forest burns.
- Economical
effect particularly
in coastal areas of
Peru and Ecuador. In
normal condition the
cold water supports
large populations of
fish, however,
during El Nino the
coastal areas are
warmer, depleting
nutrient in the area
thus causing lack of
food for the fishes.
- Health
problems, especially
in drought areas.
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| About
the name |
The
name El Nino was derived
from Spanish word that
means "a little
boy." This term was
picked because the event
usually occurs in
December, near
Christmas.
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La
Nina
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La
Nina is a contrary to El Nino,
described as unusual cold
condition in the eastern
Pacific. During this event, the
coastal areas of Peru and
Ecuador are dominated by arid
and cool weather, making it
drier and cooler than ever.
While in the western Pacific,
the condition is warmer and more
moisture, leading to high rate
of rainfall. La Nina always come
after El Nino, but not every El
Nino episode will be followed by
La Nina. The
name La Nina means "a
little girl." A slight
opposite to El Nino.
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