Intro

1. Objective 04/27/12 Describe the formation of hurricanes. Intro What is the difference between a hurricane, a typhoon, and a cyclone?

2. Hurricanes

3. Hurricanes • Tropical cyclone • Massive tropical storm that forms over warm ocean water, with extremely strong winds spiraling around a center of low air pressure • Same storm, different names: • Hurricanes • Typhoons • Cyclones

4. Hurricanes • Where? • Form over warm ocean waters near the equator • Hurricanes that effect the US begin off the west coast of Africa!

5. Hurricanes • Typhoon • Cyclone • Term used for a tropical cyclone in the Pacific Ocean near Asia • Term used for tropical cyclone in Indian Ocean or South Pacific Ocean

6. Hurricanes

7. Hurricanes • Hurricane • Term used for tropical cyclone that forms over warm ocean water in the North Atlantic or eastern North Pacific

8. Hurricanes • Structure • Coriolis Effect • Northern Hemisphere • spin counterclockwise • Southern Hemisphere: • Spin clockwise • Spiraling of winds due to the Earth’s rotation

9. Hurricanes • Eye • Eyewall • Circular region located at the center of a hurricane • Usually has calm weather • Warm air is rising, creating a low pressure zone • Region of tall clouds, heavy rains, and strong winds surrounding the eye • Most severe rain and winds in a hurricane

10. Hurricanes • Rainbands • Region of heavy thunderstorms beyond the eyewall that spiral outward from the center of a hurricane

11. Hurricanes • Formation • Energy source: • Warm water • As water vapor evaporates it carries heat energy into the atmosphere • Water vapor condenses, releasing the heat energy • Rising air spirals, creating the eye (low pressure zone)

12. Hurricanes • Formation (cont.) 3. Thunderstorms become organized and cluster together • As they strengthen they rotate, eventually creating a hurricane

13. Hurricanes • Death of a Hurricane • Wind shear • Cool water • Move over land • Change in wind speed and/or wind direction at different heights in the atmosphere • Cool ocean water does not evaporate easily • Lack of warm water for the hurricane

14. Hurricanes • Death of a Hurricane • Saharan Air Layer • Hot, cry, dusty air layer that forms over North Africa in the summer and affects the formation of hurricanes in the Atlantic Ocean

15. Hurricanes • Saffir Simpson Scale • Measures wind speed and how strong the hurricane is

16. Hurricanes • Facts • Average 6-10 per year • Hurricane Season: • July - September • Circular shape • Average diameter = 300miles • Ocean water has to be at least 80˚F to create a hurricane

17. Hurricanes • Tracking • Satellites • Airplanes • Gathers large amounts of data over wide regions • Can get directly inside a hurricane to gather data

18. Hurricanes • Dropsonde • Weather detection device designed to be dropped from a hurricane hunter aircraft to collect data on tropical storm conditions as the device falls to Earth • Collects data on global position, air pressure, temperature, humidity, wind speed, and wind direction

19. Hurricanes • Doppler Radar • Enhanced radar that can detect storm location, intensity and amount of precipitation, wind speed and wind direction, rotation patters and other valuable data

20. Hurricanes • Path • Travel from East to West while strong • Reverse when weak

21. Katrina: Path, 2005

22. Hugo: Path, 1989

23. Andrew: Path 1992

24. Camille: Path 1969

25. NY Hurricane: Path, 1938

26. Hurricanes • Record Holder • Typhoon Tip, 1979 • 1380 miles wide • Wind speeds over 190 mph

27. Hurricanes • Hurricane Safety • Evacuate!!! • Staying? • Have disaster kit containing: • Food • Water • Basic first aid • Flashlight • Board up windows • Stay indoors

29. Objective 04/27/12 Describe the formation of hurricanes. Outro Why is hurricane tracking important? Is it okay to be wrong?