El Nino and La Nina

•http://video.nationalgeographic.com/video/player/environment/environment-natural-disasters/landslides-and-more/el-nino.html

El Nino Causes

•Trade winds weaken or reverse

•Warm ocean water moves closer to South America

El Nino Effects•Weakens or stops the upwelling / animals die

•Increased rainfall in South America

•Drought in Australia

Upwelling

Diagram of El Nino•El Nino Explained

Normal /Neutral Conditions•Trade winds blow to the west

•Warm ocean water is pushed towards Australia

•Upwelling occurs

•Cool and Dry in South America

•Average rainfall in Australia

La Nina Conditions•Trade winds blow harder•Warm ocean water is pushed further to the west

•Upwelling increases•Very dry in South America•Heavy rainfall / flooding in Australia

La Nina Diagram•Diagram of La Nina Explained

QUIZ! Which is which…Normal, El Nino, La Nina?

QUIZ! Which is which…Normal, El Nino, La Nina?

How can we predict an El Nino or La Nina event?

Measures...temperaturecurrentswinds

NOAA drifting buoys

TOPEX/Poseidon (T/P) helps predict El Nino and La Nina

•http://www.youtube.com/watch?v=uySu7Zv2cbU

• During El Niño, the trade winds weaken in the central and western Pacific. The warm water moves eastward towards South America causing a rise in sea surface temperature. Rainfall follows the warm water eastward, causing flooding in Peru, but drought in Indonesia and Australia in the west. The warm water also reduces upwelling which leads to fewer nutrients in the water. Fewer nutrients mean fewer fish.

• During La Niña, the trade winds strengthen in the central and western Pacific. The warm water moves further westward towards Australia causing a drop in sea surface temperature. Rain fall moves further from the coast of South America, causing a dry period in this area.