SUMMARY
OF CURRENT CONDITIONS
At the time of TIP-7,
cold La Niņa conditions characterized the tropical Pacific (Figure 1). Temperatures
were as much as 2°C
below normal in areas of the central Pacific, and the trade winds were
significantly stronger than normal in the western Pacific. Likewise, across
nearly the entire range of longitudes shown in figure 1, the thermoline
(as measured by the 20°C depth) was shallower than normal by as much as
40 m. The transition from warm El Niņo to cold La Niņa conditions occurred
abruptly with an 8°C drop in SST over a 30-day period in May-June 1998.
Since then, the area of below normal SST's has continued to expand, although
warm surface anomalies persist in the eastern and western Pacific, and
to the north and south of the cold equatorial strip. Most ENSO forecast
models suggest that cold equatorial SST's will persist through boreal
spring, after which near normal conditions are expected to return.
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