Contents	Introduction	Normal Pacific currents		Changes with El Niño
Contents	Measurement	Effects	Research	Prediction	Conclusions

Changes to the weather and current systems due to El Niño

El Niño conditions are simply the disintegration of the Walker cell, as the feedback loop temporarily stalls. The warm waters flow back across the Pacific, upwelling stops, and the global atmospheric circulation pattern changes. Bjerknes suggested that the trigger for all this was a relaxation in the easterly trade winds, but the reasons for that are still unknown.

The form exhibited by El Niño is not always constant. For example, sometimes sometimes warm anomalies occur at Peru first and then flow across to meet the preexisting warm pool which is moving west.

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