Focus Areas E2- Oceanography

Changes during a La Niña episode

Various changes in the atmospheric and oceanic circulation are observed during a La Niña episode. Taken together, these changes are used by weather scientists as signs of an increased probability of certain weather events (e.g. storms, floods) that can have serious impacts in the short term (a few months) to medium term (a few years) on the environment and on human populations around the Pacific Basin but also for countries beyond the Pacific, including especially countries bordering the Indian Ocean.  

Quoting from the Australian Bureau of Meteorology, these indicators include:

  • Cooler than normal ocean temperatures across the central and eastern tropical Pacific Ocean.  
  • Increased convection or cloudiness over tropical Australia, Papua New-Guinea, and Indonesia.
  • Stronger than normal (easterly) trade winds across the Pacific Ocean (but not necessarily in the Australian region).  
  • High (positive) values of the SOI (Southern Oscillation Index).
    (Source: Australian Bureau of Meteorology )

Students learn about El Niño and La Niña
Students learn to identify features of El Niño and La Niña