How strong were the recent El Niño and La Niña of the late 1990s?

In the following JPL animation, you will compare the sequence of events from 1996 through 1999 documenting one of the largest El Niño events of the century followed by a strong La Niña event.  Images from Topex-Poseidon satellite are used to show changes in sea surface temperatures and in sea surface heights.

View the animation and answer the questions below:
<http://podaac.jpl.nasa.gov/sst/movies/epacific_75q.mov>

1.  What does the globe on the left show?

    a.  SST        b.  SST anomalies        c.  sea surface height        d.  sea surface height anomalies

2.  What does the globe on the right show?

    a.  SST        b.  SST anomalies        c.  sea surface height        d.  sea surface height anomalies

3.  About when did the El Niño reach its maximum strength?

    a.  Mar. 1997        b.  Oct. 1997      c.  Feb. 1998        d.  June 1998        

At the time of the maximum El Niño strength, what was the largest sea level
height anomaly in the eastern Pacific?

 a.  2 cm.        b.  5 cm.        c.  8 cm.        d. over 10 cm.

5.  For the same time as in #'s 3 and 4, what was the greatest SST anomaly?

    a.  0.5oC        b.  1.0oC        c. 1.0-2.0oC        d. over 3.0oC

6.  In February, 1998, southern California experienced a very wet month. How
strong was the El Niño in terms of SST anomalies?

    a.  weak, but growing stronger        b.  continues showing strength
    c.  strong, but growing stronger       d.  weak, and growing weaker

7.  What indicates the weakening of the El Niño and a rapid change to La Niña
conditions in May and June of 1998?

    a.  sea level heights rise in the central equatorial Pacific
    b.  sea level heights fall in the central equatorial Pacific
    c.  SST’s are much cooler in the Alaskan Gulf
    d.  SST’s are warming in the eastern tropical Pacific

8.  What is the sea surface height anomaly in the eastern Pacific in January, 1999?

    a.  10 cm. higher        b.  5 cm. higher        c.  5 cm. lower        d.  10 cm. lower

9.  What is the SST anomaly in the eastern Pacific in January, 1999?

    a.  3o C cooler        b.  1o C cooler        c. 3o C warmer        d. 1o C warmer

10.  The Scripps, UCSD, website,  http://meteora.ucsd.edu/~pierce/elnino/en97/en97.html
offers an interesting 3-dimensional look at the development of the 1997-98 El Niño.
From the monthly 3-D figures, about when did the actual El Niño begin (when warm water at depth begins to move eastward)?

     a.  Jan. 97        b.  Mar. 97        c.  May 97        d.  July 97        e.  cannot tell
 

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