Presentation is loading. Please wait.

Presentation is loading. Please wait.

El Nino and La Nina. What weather phenomena has the largest impact on weather in the western US ?

Similar presentations


Presentation on theme: "El Nino and La Nina. What weather phenomena has the largest impact on weather in the western US ?"— Presentation transcript:

1 El Nino and La Nina

2 What weather phenomena has the largest impact on weather in the western US ?

3

4 Definitions: La Niña - Unusually cold surface water temperatures in the Pacific ocean caused by strong easterly trade winds.

5

6 El Niño - Unusually warm surface water temperatures in the Pacific ocean caused by weak (or reversed direction) easterly trade winds.

7

8 El Niño and La Niña simplified… zEl Nino is the abnormal heating of Earth’s ocean surface in the Pacific. z La Nina is the abnormal cooling of Earth’s ocean surface in the Pacific.

9 Did You Know… zEl Nino means “The Christ Child” zThey were discovered hundreds of years ago zThey can be caused by underwater volcanoes z La Nina means “Little Girl” z They occur half as often as El Nino’s

10 Time Pattern zEl Nino usually lasts from a year to two years. zThe longest El Nino ever recorded lasted six years. z La Nina usually lasts nine to twelve months. z The longest ever recorded lasted three years. El Nino La Nina. Oracle Think Quest. Retrieved May 14th, 2012. http://library.thinkquest.org/5818/elnino.html

11 Causes: zEl Nino is caused when trade winds allow warm water from the Pacific to flow east. zThis builds up warm surface water that will soon cause the El Nino. z La Nina is caused when the temperatures drop in the pacific, also being blown east. z This builds up at the coasts and will cause a La Nina.

12 What causes an El Niño? Weak trade winds and weak upwelling cause warm water off the coast of S. America

13 What causes a La Niña? Strong trade winds blow surface water towards east, creating colder surface temperatures off South American coast. We get strong upwelling.

14 What causes the patterns? zNormal

15 Movement of Ocean Water zSurface currents zDeep ocean currents zUpwelling

16 Surface Ocean Currents zCurrents that are controlled by the wind. ~¼ mile depth, 10%

17 Deep Ocean Currents zCurrents controlled by water density: temperature and salinity 90% of the ocean water moves in deep ocean currents

18 Upwelling zupwelling brings up cold, nutrient-rich waters to the surface, which encourage seaweed growth and support blooms of phytoplankton.

19 Upwelling zThis happens along the coast, and when this happens it creates animal diversity. zPhytoplankton use these nutrients to grow and reproduce at rapid rates. zThis attracts organisms to areas of upwelling that rely on phytoplankton as food and, in turn, attracts their consumers. zThis areas is rich in biological activity and diversity. zApproximately half of the fish caught in the world come from areas of upwelling.

20 El Nino’s Damage Done zFloods in the Pacific states zCause tornadoes in the mid-west states zCauses severe thunderstorms in the south zNortheast typically has stormy winters, "Snowmageddon”

21 La Nina’s Damage Done z Drier and Milder conditions in the south. z Cause severe droughts in the southeast. z Cause unusual cold temperature changes along the Pacific coast. z Causes wetter conditions for the Pacific states. z Northeast will have cold periods

22 Strange phenomenon occur during an El Niño and La Niña like...

23 Brush fires caused by drought in Texas (La Niña)

24 Increased Tropical Storms (La Niña)

25 Hurricane Floyd was HUGE! (1999 - La Niña)

26 Causing devastating floods in Australia (2010-2011 La Niña)

27 Peruvian anchovy populations declined (El Niño)

28 Star Tribune Aug 2 1993 Minneapolis, MN FLOODS Upper Mississippi Basin Source: Trenberth

29 NO!!! Scientists have found no significant correlation between El Niño and La Niña weather patterns and increased tornadoes. More tornadoes through tornado alley?

30 The drought of 1988: cost about $40 billion

31

32 Watch Videos (3 minutes each) zScience Cheat Sheet http://science.discovery.com/tv-shows/cheat- sheet/videos/el-nino-and-la-nina.htm zNational Geographic Video http://video.nationalgeographic.com/video/environment /environment-natural-disasters/landslides-and-more/el- nino  La Nina water movement explained  https://www.youtube.com/watch?v=8qJYCHBEj2g https://www.youtube.com/watch?v=8qJYCHBEj2g

33 A B C QUIZ! Which is which… Normal, El Niño, La Niña?

34 Were you’re predictions correct?

35 Videos : If time zhttp://www.youtube.com/watch?v=SR5VPAqVQBw El Nino explanation video 3minhttp://www.youtube.com/watch?v=SR5VPAqVQBw z zhttp://www.youtube.com/watch?v=jEAv-9TZktY La Nina explanation video 3.5minhttp://www.youtube.com/watch?v=jEAv-9TZktY z zhttp://www.youtube.com/watch?v=iWTucpsClLc Austin newscast in January talking about Australia flooding 2minhttp://www.youtube.com/watch?v=iWTucpsClLc z zhttp://www.youtube.com/watch?v=l5x8dJ57xkk Texas weatherman predictions for this year from July 2010. about 3minhttp://www.youtube.com/watch?v=l5x8dJ57xkk z zhttp://esminfo.prenhall.com/science/geoanimations/animations/26_NinoNin a.html All three animations http://esminfo.prenhall.com/science/geoanimations/animations/26_NinoNin a.html


Download ppt "El Nino and La Nina. What weather phenomena has the largest impact on weather in the western US ?"

Similar presentations


Ads by Google