El Niño Southern Oscillation (ENSO); Ocean-Atmosphere Interactions

Lecture slides (powerpoint); Note that Figure numbers in the text below correspond to the slide sequence in the powerpoint file.

Take away ideas and understandings

  1. Mean climatology of the tropical Pacific ocean-atmosphere system.
  2. Changes in equatorial Pacific ocean and atmosphere circulation associated with El Niño and La Niña events.
  3. Two dynamic feedback processes which act to intensify El Niño and La Niña events.
  4. Why this system oscillates and the time-scale of this oscillation.
  5. Effects of El Niño/La Niña on regional and global climate.

I. General Background

II. Impacts of 1982/83 El Nino Episode (Fig 5)

III. Mean Tropical Pacific Ocean-Atmosphere Climatology

IV. End Members of ENSO Circulation

V. General History of ENSO Research; Sir Gilbert Walker (Fig 13)

VI. Mean Sea Level Pressure (MSLP) Index of ENSO

VII. General History of ENSO Research; Jacob Bjerknes (Fig 21)

VIII. General Description of ENSO Processes: Why is There an El Nino State?

IX. Why Does ENSO State Tend to Oscillate?

X. Predictions Fall 04 - Winter 05. Figures 27-39 in powerpoint.

XI. Kelvin Wave / Rossby Wave Oscillations discussed in Wednesday session.



Text by Mark Cane, Peter deMenocal, and Jim Simpson; Modified by Arnold Gordon, Fall 2004.