El Nino
Prolonged warming of the Pacific Ocean. Happens every 2-7 years and last 9 months to 2 years.
- Warms the waters replacing cold, nutrient rich water. Kills fish and birds.
- Increased rainfall in South America and flooding
- Affects the fishing industry
- Winters are warmer and drier in North America
Hurricanes
Travel poleward. Intense low pressure areas that form over warm oceans waters in the summer and early fall-the source of energy is water vapor. The low pressure causes wind to spiral inward.
- Eye of the Hurricane is calm
- Saffir Simpson scales rates hurricanes from 1-5 with a 5 having winds of 155mph and catastrophic
- Most damage is from the storm surge after the storm
Tornadoes
Form in unusually violent thunderstorms which include instability and wind shear. Warm humid conditions in lower atmosphere and cooler than normal in the upper atmosphere.
- 15 mph - 50 mph
- Up to 5,000 feet
- Ahead of cold front and low pressure systems
- The U.S. experiences more tornadoes than any other place in the world.
- 95% spin counter clockwise
- Tornado Alley: Texas, Oklahoma, Kansas