An important thing to realize is that the figures on the previous two slide are updated in
near-realtime; they are not figures that are produced months to years after the data have been
processed. This means that the first Kelvin wave was noticed by scientists connected with the
TOPEX/Poseidon project and the TOGA/TAO project in early February 1997. Because the Kelvin wave was
large, it was expected that there would be a moderate El Niño warming either in the late spring or
early summer, although at that time, no one expected that it would surpass the event of 1982-83. Thus, these
scientists were not surprised when an official NOAA El Niño advisory was issued in April.
The plots from the previous slides are still updated on a regular basis and are available over the World Wide Web.
The TOGA-TAO data can be accessed from the NOAA Pacific Marine Environmental Laboratory:
The TOPEX/Poseidon data can be accessed from the University of Texas, Center for Space Research:
Slide 15 of 27