Geoscience Reference
In-Depth Information
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Figure 11.51
El Niño events 1525-1987 classified according to very strong, strong and medium.
Source: Quinn and Neal (1992). Copyright © Routledge, London.
atmosphere - ocean coupling during ENSO events
clearly varies on multidecadal timescales.
ENSO events result from a radical reorganiza-
tion of the Walker circulation in two main
respects:
1
Pressure declines and the Trades weaken over
the eastern tropical Pacific (
Figure 11.50B
),
wind-driven upwelling slackens, allowing
the ITCZ to extend southward to Peru. This
increase in sea surface temperatures by 1-4
°
C
