1. Short term Climate change
El Niño and La Niña
What causes them?
Why do they occur?

2. El Niño and La Niña
Are short term changes in the Tropical Pacific Ocean by changes in ocean surface currents and prevailing winds.
Both influence weather patterns all over the world.

3. What is El Niño?
A climate event that occurs every two to seven years in the Pacific Ocean , during which winds shift and push warm water toward the coast of South America.
Unusual pattern of warm winds forms over the western Pacific.
Causes vast sheet of warm water to move eastward toward the South American coast.
Disrupts the cold ocean currents along the western coast of South America.
Changes weather pattern. Often bring severe conditions such as heavy rains normally in dry areas or droughts in wet areas.

4. The Effects of El Niño are Worldwide
Wet winters over southeastern United States
Drought in Indonesia and Australia, and other places that are typically wet
Flooding in South America in areas typically dry
Wildfires and mudslides
Warmer winters in the upper Midwest united states and Canada

5. The Effects of El Niño are Worldwide
El Niño’s warm current of nutrient-poor tropical water replaces the cold, nutrient-rich surface water where Peru’s fishing industry usually is vibrant

6. What is La Niña? Opposite of El Niño event.
A climate event in the eastern Pacific Ocean in which surface waters are colder than normal.
Brings colder than normal winters and greater precipitation to the Pacific Northwest and the north central United States.
Greater hurricane activity in the western Atlantic

7. Under normal conditions, easterly trade winds move water
and air warmed by the sun towards the west
This also creates an upwelling of nutrient-rich cold water along
the coasts of Peru and Ecuador
What is Upwelling? – The movement of cold water upward from the
deep ocean that is caused by wind.

8. Under El Niño conditions, warm, nutrient-poor water
slumps towards the east because of weakening winds.
The nutrient-rich cold water does not get pulled
up as much – Little upwelling

9. Under La Niña conditions, unusually cold water
pushes up in the east Pacific
Often follows El Niño
Too much upwelling

10. http://www. youtube. com/watch

11. El Niño vs. La Niña El Niño La Niña
Usually more intense effects than La Niña
Unusually warm ocean temperatures in eastern Pacific (west united states)
Summers in central united states tend to be wetter and cooler
Usually follows El Niño, but not always
Unusually cold ocean temperatures in eastern Pacific (west united states)
Summers in central united states tend to be drier and warmer

12. El Niño vs. La Niña El Niño La Niña
Causes drier weather on West Pacific (Australia, Indonesia, etc)
Warmer winters in the upper Midwest states and Canada
Wet winters over southeastern United States
Causes wetter weather on West Pacific (Australia, Indonesia, etc)
Colder winters in the upper Midwest states and Canada
Dry winters over southeastern United States

13. La Niña to blame?
Recent droughts occurred during latest La Niña