Science Mr. G/Mrs. Kelly Name: KEY Date: Inv.6.1 - That s a Fact: An Introduction to Thunderstorms, Tornadoes, and Hurricanes (pgs.92-97) 1. Define lightning. A bright flash that is produced due to electrical discharge and occurs during a thunderstorm. 2. Define thunder. A loud sound produced by rapidly expanding Heated air that typically follows lightning and occurs during a thunderstorm (usually follows lightning) 3. What happens to air immediately around lightning? The air is suddenly heated to high temperatures of just 30,000 degrees Celsius and subjected to high pressure and it expands rapidly 4. What are thunderstorms accompanied by? Gusty winds, heavy rain, sleet, snow, or hail, or by no precipitation at all 5. What can a severe thunderstorm also produce? Flash floods and tornadoes 6. Where do thunderstorms mainly occur? Generally occur in mid-latitudes in the southeastern United States, they most often occur along the Gulf Coast especially in Florida 7. When do most thunderstorms occur? spring and summer months during the warmest part of the day, When warm air is in motion
8. How much area does a well-developed thunderstorm cover? Can cover an area as large as 8 to 16 square kilometers or 5 to 10 square miles 9. How does hail form? When the temperature of the Thundercloud Falls below freezing and winds are strong, Raindrops turn to hail 10. How much energy can a typical bolt of lightning discharge? As much energy as a medium-sized nuclear reactor can in the same amount of time, currents up to 160,000 amps 11. How many thunderstorms occur on Earth at any given moment? 1500-2000 thunderstorms, Can trigger 6000 or more lightning flashes per minute 12. Do we see lightning or hear thunder first? What does this mean? Lightning is seen before Thunder, The time difference between the lightning Flash and the sound of thunder can be used to calculate the distance from a storm (Flashes of lightning followed by Thunder close together indicate the storm is very close) 13. What is a tornado? A rotating column of air that forms from thunderstorms over dry LAND under special conditions, when moist warm air meets cold dry air head on 14. Where do most tornadoes occur? The United States has the most tornadoes in the world, most happen in Tornado Alley in the Western Plains or in Dixie Alley in the Lower Mississippi Valley Between the Gulf States and Tennessee
15. When do most tornadoes occur? Three fourths of all tornadoes develop between March and July during late afternoon, the month of May = greatest number of tornadoes (about 5 per day), April = most violent 16. What is the diameter of most tornadoes? Between 100 and 600 meters (328 and 1,969 feet) 17. How fast can the winds in a tornado s vortex be? Up to 350 kph ( 217 ) 18. What are waterspouts? Tornadoes that form over water 19. What is most dangerous about a tornado? Strong winds that can lift objects and turn them into dangerous, high speed missiles. 20. Define Enhanced Fujita Scale. A scale for measuring the strength of tornadoes. 21. The Enhanced Fujita Scale better relates wind speeds to the amount and type of damage. 22. ENHANCED FUJITA SCALE OF ES F-Scale Number Intensity Phase Wind Speed Type of Damage F0 GALE 65-85 Tree branches broken, shallow rooted trees pushed over, covering/shingles damaged. F1 WEAK 86-110m ph Trees uprooted, poles bent, school windows broken, mobile homes rolled over or moved upside down, moving cars pushed off roads.
F2 STRONG 111-135 Tree trunks snapped, trees uprooted, poles collapsed, walls of schools collapsed, mobile homes separated from undercarriages. F3 SEVERE 136-165 Trees debarked and uprooted. Exterior and interior walls of schools collapsed, mobile homes completely destroyed, large sections of big box stores destroyed, cars overturned. F4 DEVASTATING 166-200 Large sections of school buildings destroyed, walls collapsed on single family homes, high rise buildings deformed, large objects including cars thrown, buildings with weak foundations moved. F5 INCREDIBLE >200 Well-constructed buildings completely destroyed, cars carried long distances, all trees downed with bark stripped off. 23. What distinguishes hurricanes from thunderstorms and tornadoes? Hurricanes are MASSIVE rotating storms formed when warm, moist air rises over tropical waters. 24. Define typhoon. A massive rotating storm that forms north of the equator in the western Pacific Ocean. Another name for a hurricane. 25. Define cyclone. A MASSIVE rotating storm that forms in the Indian Ocean and off the coast of Australia. Another name for a hurricane. 26. Describe how hurricanes can vary in size. Diameter of 100 km ( 62 miles ) to 1,100 km ( 684 miles ). 27. How fast can hurricanes move? 8 to 24 kph ( 5-15 )
28. Define tropical storms. An organized, low-pressure system of storms over warm ocean waters. It has wind speeds between 63-117 kph, and may rotate. 29. Define the Saffir-Simpson Scale. A scale used to measure hurricane strength. 30. What happens to a hurricane when it hits land and why? It becomes less powerful since it gets most of its energy from the warm ocean water. 31. How long can hurricanes last? What does this have to do with naming them? A week or longer and many can occur at the same time so naming them reduces confusion. 32. SAFFIR/SIMPSON HURRICANE SCALE Categor y Wind Speed Damage Type of Damage Storm Surge 1 74-95 119 to 153 kph 74 to 95 Minimal No significant damage to buildings. Damage primarily to unanchored mobile homes, Shrubbery, and trees. Some coastal flooding and minor Pier damage. 1-2 meters 4-5 ft 2 154-177 kph 96-110 Moderate Some damage to Roofing, doors, and windows. Considerable damage to vegetation and mobile homes. Flooding damage to piers and small craft. 2-2. 5 m 6-8ft. 3 178-208 kph 111-129 Extensive Some structural damage just small residences and utility buildings. Mobile homes destroyed. Flooding near Coast destroys small structures semicolon floating debris damage is larger structures. Inland flooding possible. 2.7 to 3.7 m 9-12 ft. 4 209-251 Extreme Complete roof damage on small 4-5.5 m
kph 130-156 homes, major erosion of beaches, inland flooding possible. 13-18 ft. 5 worst 252 + kph 157+ Catastrophic Complete roof failure on many homes and buildings. Some buildings completely destroyed. Flooding causes damage to lower floors of structures near shoreline. Massive evacuation of people possible. 5.5+ m 18+ ft.