1. La Nina and El Nino Phenomena

2. http://edition.cnn.com/video/#/video/weather/2009/07/27/byrnes.ctw.aregenti no.el.nino.cnn?iref=videosearchhttp://edition.cnn.com/video/#/video/weather/2009/07/27/byrnes.ctw.aregenti no.el.nino.cnn?iref=videosearch Impact http://www.youtube.com/watch?v=AEoHz56jWGY El Nino Definition

3. Water (Ocean) and Air (Atmosphere) Interactions Trade Winds Ocean CurrentsAir Pressure Air and water temperature Source: http://esminfo.prenhall.com/science/geoanimations/animations/26_NinoNina.html Animation La Nina 2011 video http://www.youtube.com/ watch?v=iWTucpsClLc&NR= 1&feature=fvwp

4. What do we already know? Density: Warm air is less dense than cool air. Warm air rises. Cool air sinks. (convection) Pressure:  High temperature means low air pressure and low temperature means high air pressure.  High pressure = fair weather. Air masses press down, Warm air cannot rise and form clouds. Low pressure = cloudy, rainy weather. Air masses move apart, warm air rises and form clouds.  Air moves from an area of high to low pressure.

5. NORMAL CONDITIONS Guide questions: 1.In what direction would the wind blow? 2.Describe the climate in the Western Pacific? Eastern Pacific? Consider a. pressure systems (high or low) b. ocean temperature Western Pacific (Australia) Eastern Pacific (Peru)

6. Guide questions: 1.Describe what is happening in the atmosphere (Walker Circulation Cell)? 2.Why is rain most likely to happen over a longer period in the Western Pacific? Western Pacific (Australia) Eastern Pacific (Peru) Trade winds blowing

7. LA Nina CONDITIONS Western Pacific (Australia) Eastern Pacific (Peru) Guide questions: 1.What would happen to the water in the Eastern Pacific if the trade winds got stronger? 2.What would be the result of cold water moving towards the West (Think about the weather)? Trade winds blowing

8. Western Pacific (Australia) Eastern Pacific (Peru) Guide questions: 1.Why is there heavier rain observed in more countries in the western Pacific? 2. What changes in weather would occur in North America? Hint: red circle

9. Trade winds weaken

10. Global Impact

11. La Nina

13. http://www.youtube.com/watch?v=ovDp1crqdOU El Nino/La Nina video (with impact on fishing and US weather)

14. During non-El Niño years, the southeast trade winds, drag surface water westward away from shore. As surface water moves away, upwelling brings up colder waters from depths of 40-80 meters or more. This deep sea water is rich in nutrients which can sustain large fish populations.trade windsupwelling

15. During an El Niño event, the southeast trade winds weaken and so does the amount upwelling in the eastern Pacific.El Niño eventtrade windsupwelling The deeper thermocline means that any upwelling that does occur is unable to tap into the rich nutrients found in deeper waters. Consequently, warm nutrient-poor water predominates the region and a decrease in the fish population is observed.thermocline

16. Drought in Southern Africa, Southern India, Sri Lanka, Philippines, Indonesia, Australia, Southern Peru, Western Bolivia, Mexico, Central America Heavy rain and flooding in Bolivia, Ecuador, Northern Peru, Cuba, U.S. Gulf States Hurricanes in Tahiti, Hawaii Atmospheric Consequences of El Niño influencing weather patterns worldwide

17. Why do we care: Global climate impacts continued Floods Lakeport, California (1998) Fires Australia (1998)

18. SOURCES: http://esminfo.prenhall.com/science/geoanimations/animations/2 6_NinoNina.htmlhttp://esminfo.prenhall.com/science/geoanimations/animations/2 6_NinoNina.html http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/eln/home.rxml PAGASA-DOST