Chapter 18 - El Niño & La Niña
What does ENSO stand for?
(El Niño Southern Oscillation).
Explain the Weather during El Niño
Brings lots of rain and flooding to California and South America; drought to Australia and Indonesia
Explain the Weather during La Niña
Brings very dry air (drought) to California and South America; rain and flooding to Australia and Indonesia
How often do we experience El Niño conditions?
Occurs every 2 to 7 years
Explain the Wind during La Niño
Strong trade winds
What is the other part of the ENSO cycle?
The other part of this cycle is called La Niñaand results in cooling
Where does the upwelled water originate?
This is water that sank at the poles as NADW or AABW then crawled along the ocean floor towards the equator.
what is upwelling?
Upwelling is when cold, dense bottom water rises to the surface.
Explain the Wind during El Niño
Weak trade winds
Where is the drought caused by in the El Niño ?
Western Pacific (Australia and New Guinea)
La Niña
a. colder-than-average surface temperatures in the eastern Pacific b. strong trade winds c. strong westward-moving equatorial current d. a strong Peru Current with significant coastal upwelling
4 WAYS TO DETECT AN El Niño
a. warmer ocean temperatures than usual in the Eastern Pacific along the coasts of Ecuador and Peru. b. weak trade winds c. strong eastward-moving equatorial countercurrent d. weakened Peru Current d. diminished upwelling along the western margin of South America
El Niño & La Niña
-El Niño-Southern Oscillation (ENSO) is an irregularly periodical variation in winds and sea surface temperatures over the tropical eastern Pacific Ocean, affecting much of the tropics and subtropics. -The warming phase is known as El Niño and the cooling phase as La Niña. Southern Oscillation is the accompanying atmospheric component, coupled with the sea temperature change: -El Niño is accompanied with high, and La Niña with low air surface pressure in the tropical western Pacific. -The two periods last several years each (typically three to four) and their effects vary in intensity.
Where is the heavy rainfall brought on by El Niño .
Eastern Pacific (Peru, California, Mexico)
What is the name of the warming part of the ENSO cycle?
El Niño
