Remember “normal” ocean circulation?
El Nino? (warm) Trade winds weaken Thermocline drops Upwelling is cut off SST rises in E.Pacific High & Low pressure areas in Pacific reverse Disrupts fish/bird populations in E.Pacific Occur every 2-7 years Lasts months
La Nina? (cold) Trade winds strengthen SST decrease in E.Pacific Upwelling increases Occurs every 3-5 years Lasts 9-12 months
Prentice Hall Textbook animation linkTextbook animation link
Prentice Hall Textbook animation linkTextbook animation link
Prentice Hall Textbook animation linkTextbook animation link
Normal El nino – strong counter-current
Sea surface anomalies associated with El Nino
SST differences between El Nino and La Nina
A B C QUIZ! Which is which… Normal, El Nino, La Nina?
Were you’re predictions correct?
What are the effects of El Nino?
Brush fires caused by drought
Increased Tropical Storms
Devastating floods
Peruvian anchovy populations decline
Winter NH El Nino La Nina
Summer NH El Nino La Nina
El nino - precipitation
Hurricanes El Niño contributes to more eastern Pacific hurricanes and fewer Atlantic hurricanes. La Niña contributes to fewer eastern Pacific hurricanes and more Atlantic hurricanes. US hurricane damage
US Tornados Tornado activity Depends on the location of the polar jet stream El Nino: More to the south La Nina: more to the north
Measurements! How can we predict an El Nino or La Nina event?
Buoys Measure... temperature currents winds
Radiosonde Weather balloon Monitors global weather and climate patterns
Satellites Provide data on: Rainfall Wind Ocean temp. Sea surface height Ocean color Surface currents
TOPEX/Poseidon (T/P)
Click here to find out what the current sea surface temperatures are. Are we in an El Nino, La Nina, or neither?