1. SCIENCE NEWS

2. TROPICAL CYCLONES

3. Weather related deaths in the u.s.

4. Tropical Cyclones Most violent storms on Earth
Large rotating low pressure tropical storms
Known as
Typhoons in the W Pacific
Cyclones in the Indian Ocean
Hurricanes in the N Atlantic, Caribbean & Gulf of Mexico

5. Occurrences

6. Cyclone Formation Require two conditions
Abundant supply of warm ocean water
&
Lifting mechanism

7. Cyclone Stages Formative Stage
Energy comes from condensing water vapor
Develop most often in late summer when warm
water temperatures provide energy and
moisture
Begins as a tropical disturbance
Low pressure area over warm water fueled by precipitation and latent heat
Initial stage is not well understood

8. Developmental Stage
Tropical depression Coriolis effect cause rotation, Counterclockwise in the N hemisphere
Tropical depression Tropical depression – winds do not exceed 61 kilometers (38 miles) per hour

9. Tropical Depression

10. Mature Stage Air pressure at the center continues to decrease
Increasing winds toward the center
Tropical storm – winds between 61 to 119 km/h (38 and 74 miles) per hour
Cyclone – winds exceed 120 km/h

11. Fully Formed Cyclone

12. Dissipation Stage Diminish in intensity whenever
• They move over cooler ocean water
• They move onto land
• The large-scale flow aloft is unfavorable
Can undergo several intensities

13. Hurricanes
Profile
Form between the latitudes of 5 degrees and 20 degrees North
North Pacific has the greatest number per year
Wind speeds reach 300 km/hr
Generate 50 foot waves at sea

14. Parts of a hurricane Eye • At the very center
• About 20 km (12.5 miles) diameter
• Precipitation ceases
• Winds subsides
• Air gradually descends and heats by
compression
• Warmest part of the storm

15. Parts of a hurricane Eyewall • Wall of cumulonimbus clouds
• Greatest wind speeds
• Heaviest rainfall

17. Hurricane Destruction
Factors that affect amount of hurricane damage
Strength of storm (the most important
factor)
Size and population density of the area
affected
Shape of the ocean bottom near the shore
Saffir-Simpson scale ranks the relative
intensities of hurricanes

19. hurricane Destruction
Storm surge - large dome of water 65 to 80 kilometers (40 to 50 miles) wide sweeps across the coast where eye makes landfall
Wind damage
Inland flooding from torrential rains

20. Storm Surge

21. Hurricane Katrina

23. Hurricane Katrina
Of the 2005 Atlantic hurricane season was the costliest hurricane, as well as one of the five deadliest, in the history of the United States. Among recorded Atlantic hurricanes, it was the sixth strongest overall.

24. National Hurricane Center