What happened in 1982
El Nino?
Mehmet ILICAK
RSMAS, University of Miami
2005
1
Outline
• What is El Nino?
• Why 1982?
• Oceanographic Events
• Meteorological Events
• Summary
2
What is El Nino?
• major temperature fluctuations
in surface waters of the
tropical Eastern Pacific Ocean.
• Non-El Nino conditions the
trade winds blow towards the
west across the tropical
Pacific.
• During El Nino, the trade
winds relax in the central and
western Pacific leading to a
depression of the thermocline
in the eastern Pacific, and an
elevation of the thermocline in
the west.
3
Why 1982 El Nino?
• The strongest and most devastating of the
century.
• 2,000 deaths.
• $13 billion in damage to property and
livelihoods.
4
Oceanographic Events
• The Annual Cycle in the Tropical Pacific
• The Canonical El Nino
• Theory
• 1982-1983 El Nino
“Oceanographic Events during El Nino”, Mark A. Cane
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6
Standard El Nino Phases
• Prelude: Strong easterlies, high sea level,
deep thermocline.
• Onset: East trade winds begin to diminish
• Event: Warming the South Coast of
America, westerly winds, high sea level
• Mature Phase: Another warming in
December, trade winds become normal
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Theory
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1982-1983 El Nino
• West coast sea level
•
decreased in April and
continued to drop
throughout the year.
East Coast Islands
sea level increased
25cm instead of
10cm.
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SST Anomalies
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Meteorological Aspects of El Nino
• In normal conditions, Walker Circulation
12
Typical El Nino vs. 1982 El Nino
Atm. Conditions after the peak of
Typical El Nino
1982 El Nino Atm.
Conditions
13
Possible reasons of 1982 El Nino
• Swing in the Southern
Oscillation
• El Chichon eruption
• The El Chichon eruption of 6th
April 1982 was powerful
enough to eject aerosols and
dust particles into the
stratosphere, resulting in
greater scattering and
reflection of incoming sunlight,
thus dampening the warming
effect of El Niño.
14
December 1982-February SST & SST
Anomalies
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