El Niño/Southern Oscillation (ENSO)• Chicken and Egg scenario – ocean

temperatures or trade winds?

This decreases during El NiñoIncreases during La Niña

http://esminfo.prenhall.com/science/geoanimations/animations/26_NinoNina.html

Enso Neutral Conditions

El Niño/Southern Oscillation (ENSO)1. Heavier rainfall over coastal equatorial South America2. Drought in Western Pacific (Indonesia & Australia)3. Increased transmission of disease

More water = increased mosquitoesLess water = flies

4. Migration of fish species (North or South – Inshore or Out)5. Death of seals and sea birds due to changing fisheries6. Heavier rains in the southwestern deserts of United States7. Fewer hurricanes in the Atlantic

2010-2011 Australia has record flooding?• La Nina or El Nino• Weak or Strong

El Nino

La Nina

Tornados

Tornados

Tornados

• Tornado formation: http://www.youtube.com/watch?v=7KDz6dGQ5RE

• Tornado Formation: http://www.youtube.com/watch?v=MjjwPQRVbWk

• Tornado Formation http://www.youtube.com/watch?v=7bHSS1ImFQI

1. Anatomy of a Hurricanehttp://www.youtube.com/watch?v=HJydFJORWf4&feature=related

2. Hurricane Formation: http://www.youtube.com/watch?v=SNEG4YKElgY

2005 Hurricane tracks

Hurricanes• Severe weather events:• Tropical cyclones• Atlantic Ocean = hurricanes• Pacific Ocean = typhoons• Indian Ocean = cyclones

Category One Hurricane: Winds 74-95 mph Category Two Hurricane: Winds 96-110 mph - Storm surge generally 6-8 feet above normalCategory Three Hurricane: Winds 111-130 mph - Some structural damage to small residencesCategory Four Hurricane: Winds 131-155 mph - Complete destruction of mobile homesCategory Five Hurricane: Winds greater than 155 mph - Storm surge generally greater than 18 ft above normal and framed homes destroyed

Hurricanes1. Hurricanes are powered by the energy released during condensation

2. Hurricanes are steered by prevailing wind patterns and wind sheer will destroy a hurricane.

3. What are positive and what are negative feed-back-loops for hurricanes

4. When winds reach 74mph a tropical storm becomes a hurricane

5. Why is the eye clear? Air coming in from the eye wall is coming inward towards the center from all directions. This convergence causes the air to sink in the eye. This sinking creates a warmer environment and the clouds evaporate leaving a clear area in the center.

Katrina

Katrina

Lightning

What do you know about lightning

1. Lightning 5 min. – http://www.youtube.com/watch?v=Q3Awp-3CxSU

2. http://www.youtube.com/watch?v=6MUYsIjTKvk

LightningThunder and Lightning

1. Sound travels about one mile every 5 secondsSo if you count to ten the storm is 2 miles away

2. Thunder rumbles because the sound from different points on the bolt reaches our ears at different times

3. Thunder, is produced by the heating (expansion) and cooling (contraction) of the air around a lightning strike.

4. Lightning forms from negative charges at the bottom of the cloud that meet with positive charges from the ground. A stepped leader from the cloud meets a streamer from the ground. Visible light moves up and charge flows down. Individual charges are drained separately causing lightening to flash and strike multiple times in one location.