1. Southern Oscillation”
“El Niño -
Southern Oscillation”
Outline:
What is El Nino?
How does it work?
What affect does El Niño have on California?

3. What is El Niño? El Niño is: El Niño occurs:
The name, “El Niño” (means ‘boy child’ in Spanish) as it often occurs around Christmas time.

4. What is El Niño? El Niño is: El Niño occurs:
The name, “El Niño” (means ‘boy child’ in Spanish) as it often occurs around Christmas time.
a warming of the equatorial eastern Pacific Ocean
about about once every 2 to 7 years

7. Normal Conditions

9. El Niño Conditions

10. ‘Normal’ conditions (sea surface temps)

11. El Niño (sea surface temps)

12. How does El Niño work? El Niño is a coupled ocean-atmosphere process
It involves:
_____________ of the trade winds
__________of the eastern equatorial Pacific
_______ movement of the heavy rain region
_________ pressure in the west and reduced pressure in the east

13. How does El Niño work? El Niño is a coupled ocean-atmosphere process
It involves:
_____________ of the trade winds
__________of the eastern equatorial Pacific
_______ movement of the heavy rain region
_________ pressure in the west and reduced pressure in the east
Weakening
Warming
Eastward
Increased

15. Normal conditions:
warm water and rain in the west Pacific
El Niño conditions: warm water and rain in the central Pacific

16. ENSO (El Niño-Southern Oscillation)
The Southern Oscillation:
is the part of El Niño
The Southern Oscillation Index is the pressure difference between Tahiti and Darwin:
During El Niño, the pressure is _______ in the west and _______ in the east
During El Nino, the Southern Oscillation Index is (positive/negative).

17. ENSO (El Niño-Southern Oscillation)
The Southern Oscillation:
is the part of El Niño
The Southern Oscillation Index is the pressure difference between Tahiti and Darwin,
During El Niño, the pressure is _______ in the west and _______ in the east
During El Nino, the Southern Oscillation Index is (positive/negative).
atmospheric
Pressure(Tahiti) – Pressure(Darwin)
higher
lower

18. Southern Oscillation Index

19. How does El Niño affect the other parts of the globe
May change ‘normal’ storm tracks
i.e.
Wetter in California
Some areas flood, other areas have drought

20. How does El Niño affect the other parts of the globe
May change ‘normal’ storm tracks
i.e.
Warmer and drier in pacific northwest
Wetter in California
Wetter over Southern States
Some areas flood, other areas have drought

24. m

25. El Niño

27. El Nino…
…_________________________________

28. El Niño… …is an important modifier of local climates
…may change global wind patterns
…can cause floods or drought
…is NOT a storm!!!
…is pretty fascinating!!!