Atmospheric circulation is coupled to ocean surface behavior

El Nino is the dominant source of variability in the climate system on interannual to decadal time scales.

El Nino is characterized by major shifts in global precipitation patterns, associated with a weakening of the trade winds and warming of the eastern Pacific Ocean and formation of intense rain over the warm water.

El Nino's occur every 4--7 years with varying increases in intensity. The periodicitiy and the overall cause are not well understood The coupling between changing sea surface levels and temperature to atmospheric circulation is complex!

Note however, until recently its been technically difficult to measure sea surface temperature and the most realible data only starts in 1981 . Now of course, we have all kinds of data which can be represented visually (top panel is winds, middle is sea surface height, bottom is sea surface temperature ).

There is every possibility that Global Warming will increase the amplitude of this year's El Nino.

This year's El Nino

Animated Comparison of 4 El Nino's

Summer Time Global Consequences

Winter Time Global Consequences

US Temperature Anomolies

Global Effects of the 82/83 El Nino

1.Australia-Drought and bush fires
2.Indonesia, Philippines-Crops fail, starvation follows
3.India, Sri Lanka-Drought,fresh water shortages
4.Tahiti-6 tropical cyclones
5.South America-Fish industry devastated
6.Across the Pacific-Coral reefs die
7.Colorado River basin-Flooding, mud slides
8.Gulf states-Downpours cause death, property damage
9.Peru, Ecuador-Floods, landslides
10.Southern Africa-Drought, disease, malnutrition

Internet Resource Alert:

Comprehensive El Nino Site

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