Everything You Need to Know About Hurricanes
•Download as PPT, PDF•
1 like•2,368 views
Recommended
More Related Content
What's hot
What's hot (20)
Viewers also liked
Similar to Everything You Need to Know About Hurricanes
Similar to Everything You Need to Know About Hurricanes (20)
Recently uploaded
Recently uploaded (20)
Everything You Need to Know About Hurricanes
- 1. Hurricanes
- 2. The Producers Researcher: Janvi Writer/CEO: Aditi Publisher: Beatrice Technical Producer: Sarah
- 4. Tropical Cyclones Hurricane: regional name for a tropical cyclone. Tropical cyclone: low-pressure center and intense thunderstorms. Tropical depressions: < 39 mph winds Tropical storm: > 40 mph winds Typhoon Axel and Cyclones Mark and Betsy
- 5. Names of Tropical cyclones with winds greater than 74 mph
- 6. Parts of a Hurricane
- 7. The Eye • Calm center 20-40 miles diameter • Winds and rain stop • Sea may be violent • Lowest atmospheric pressures in the hurricane Eye (Hurricane Katrina)
- 8. The Eye Wall • Surrounds the eye • Greatest wind speeds and precipitation. • Eye wall replacement cycle: eye may change size, causing another eye wall to form. outer eye wall inner eye wall
- 9. Rainbands Rainbands • Ring of thunderstorms that rotate counterclockwise • Width: few miles to tens of miles • Length: 50-300 miles • Calm weather between bands • Tornadoes often form in rainbands on land. (Hurricane Ivan)
- 10. Quiz I! Match the following items to their characteristic quality: A. Eye 1. Most destructive B. Eye Wall 2. Lowest pressure C. Rainbands 3. Causes tornadoes
- 11. Formation
- 12. How to Make a Hurricane in 5 Easy Steps!
- 13. Hurricane Maintenance Winds converge and push air upward. Strong winds continue blowing and maintain the speed of the storm Storm weakens when there’s a difference in wind speeds.
- 14. Movement
- 15. Movement Controlled by winds moving westward. Coriolis Effect: Earth’s rotation causes hurricanes to turn towards poles. Landfall: eye crosses coastline, which experiences only half the storm. The Coriolis Effect
- 16. Tracks Track: cyclone’s path of motion. Track is deflected north by winds. Global cyclone tracks (1985-2005)
- 17. Dissipation How a Hurricane Loses Strength and Disintegrates ► Moving over land or low temperature waters. ► Remaining in one area for too long. ► Outer eye wall forms. Hurricane Katrina
- 18. Quiz II! What is the effect that causes hurricanes The Coriolis Effect to turn towards the Earth’s poles?
- 19. Categorizing “At last!! They’ve named a hurricane after you and your mother!”
- 20. The Saffir-Simpson Scale Rates hurricane intensity on scale of 1-5. Factors: Damage Flooding Wind speed Pre-Katrina Post-Katrina
- 21. Category 1 Wind speed: 74-95 mph (Slightly higher than top speed of cheetah) Storm surge: 4-5 feet Little damage and flooding
- 22. Category 2 Wind speeds: 96-110 mph (Top speed of baseball pitch) Storm surge: 6-8 feet Slight damage on buildings and plants. Chances of floods
- 23. Category 3 Wind speed: 111-130 mph (Speed of bullet train) Storm surge: 9-12 feet Damage on building structures Flooding occurs; evacuation may be required.
- 24. Category 4 Wind speed: 131-155 mph (Wind speed of leaf blowers) Storm surge: 13-18 feet Major damage to buildings, trees, and coastal floors.
- 25. Category 5 Wind speed: > 155 mph (Diving speed of Peregrine falcon) Storm surge: > 18 feet Homes can be washed away. Low-lying residences must be evacuated.
- 27. Naming Hurricanes Named by location from list of names. Names alternate male and female. After all names on list are utilized, Greek alphabet used.
- 28. Quiz III! What is the most important factor in Wind Speed determining a hurricane’s category?
- 30. Result of Hurricane Katrina Damage Fatal mudslides and floods can occur. Buildings can be washed away. People may be killed or severely injured.
- 31. Cost Dependent upon: – hurricane intensity – location – response Category 1 •little damage •$1000’s Category 2-3: •significant damage •$100,000’s Category 4-5: •extensive damage •$1,000,000,000’s
- 32. Safety …Because Fremont’s really going to get hit by a hurricane. Be aware of emergency plans and procedures. Identify potential hazards. Shut off utilities (gas, electricity, water). Discard contaminated food. Don’t start fuel-burning devices.
- 33. Observation Far from land: tracked by satellites Near land: tracked by aircrafts or Doppler radar Doppler updates on location and intensity.
- 34. Forecasting Track predicted by hurricane pressures. Computer software produces models and predicts rainfall. Intensity of storm least accurately predicted.
- 35. Beneficial Effects Moderates global heat balance Stirs up waters of coastal fish breeding areas Spurs redevelopment of housing
- 36. Global Warming Increase in global temperatures Increase in water temperatures Increase in hurricane intensity
- 37. Quiz IV! Satellite Name one of the tools used to track hurricanes. Doppler radar Airplanes
- 38. Extraterrestrial Hurricanes Why can’t true There’s no water! hurricanes form on Duh. other planets?
- 39. Jupiter
- 40. Saturn
- 42. Great Hurricane of 1780 • Deadliest hurricane ever recorded • Category 4 • Struck the Caribbean Islands
- 43. Hurricane Ivan (2004) • Category 5 • Moved from Atlantic Ocean to Caribbean Sea • Cost: $19 billion
- 44. Hurricane Katrina (2005) • Costliest and deadliest • Category 5 • Moved from Bahamas to southern U.S. • Cost: $81 billion
- 45. Hurricane Paul (1982) • Second deadliest East Pacific storm • Category 2 • Moved from Central America to Baja California • Caused flooding and mudslides
- 46. Quiz V! What are the two planets (besides Earth) Saturn and Jupiter that have cyclonic storms?
- 47. Credits Information CDC Emergency Preparedness & Response About The Pew Center Wikipedia Atlantic Oceanographic and Meteorological La
- 48. Credits Images Cyclone Tracy Meteorological Information University of South Florida The NASA SCIence Files Mission 2010 [MIT] Wikipedia The National Center for Atmospheric Research Vantage Point Guides Weather Wiz Kids State of New Hampshire Natural Hazards Mitigation Plan CartoonStock Irresponsible Journalism NOAA Satellite and Information Service Associated Press: Hurricane Season 2006
- 49. Credits Animations/Music The National Climatic Data Center Merry-Go-Round of Life [Howl’s Moving Castle] ASesgui @ Youtube.com Joe Hisaishi Excremental Intermission Tim Halbert
- 50. -EndWe hope you enjoyed the show! :)
Editor's Notes
- A hurricane is a tropical cyclone that forms over oceans. A tropical cyclone is a type of storm characterized by a low-pressure center and thunderstorms with strong winds and rain. Depending on location and strength, a tropical cyclone can be known as a hurricane, typhoon, tropical storm, cyclonic storm, or tropical depression. A hurricane’s wind speeds must be at least 74 mph. If the wind speed ranges from 40 to 73 mph, it is known as a tropical storm and assigned a name. Tropical cyclones with maximum surface winds less than 39 mph are known as tropical depressions.
- Hurricanes are the most common, as they occur in the North Atlantic Ocean, the Northeast Pacific Ocean east of the dateline, or the South Pacific Ocean east of 160E. Next are typhoons, which occur in the Northwest Pacific Ocean west of the dateline (on the right of the map). A severe tropical cyclone occurs in the Southwest Pacific Ocean west of 160E or Southeast Indian Ocean east of 90E. Severe cyclonic storms occur in the North Indian Ocean, while tropical cyclones occur in the Southwest Indian Ocean.
- A hurricane is made up of three important parts. These parts are the eye, the eye wall, and the rain bands.
- The eye, the calmest part of the hurricane, is located at the hurricane’s center and can have a width of 20-40 miles. There is usually very little wind and rain near it. It has the lowest atmospheric pressure in the hurricane. The eye will develop when the maximum sustained wind speeds exceed 78 mph. As the storm strengthens, the eye decreases in size. In strong tropical cyclones, the eye is characterized by light winds and clear skies. In weaker tropical cyclones, it’s less defined and can be covered by the central dense overcast, an area of high, thick clouds.
- The eye wall surrounds all or most of the eye. It consists of a ring of thunderstorms that produce heavy rains and strong winds. The side of the eye wall where the wind blows in the same direction as the hurricane’s forward motion is the most destructive part of the hurricane. Changes in the eye wall can cause changes in wind speed, which is an indicator of the hurricane’s intensity. When the eye either grows or shrinks in size in category three hurricanes or stronger, concentric or double eye walls can form. This is called the eye wall replacement cycle.
- Rainbands are curved bands of clouds that trail away from the eye wall. They spiral slowly counterclockwise and range in width from a few miles to tens of miles. They are capable of producing heavy bursts of rain and wind. The outer rain bands can extend a few hundred miles from the eye of the hurricane. Their length ranges from fifty to three hundred miles. Rain bands are part of the evaporation/condensation cycle that feeds the hurricane. Tornadoes often form in the rainbands that are located on land.
- Answers: 2 1 3
- In order for a hurricane to form, a thunderstorm must undergo a continual evaporation-condensation cycle of warm, humid air. Surface winds must occur at higher altitudes. There must be a difference in air pressure between the surface and high altitude.
- Hurricanes form in the warm tropical waters over 80 degrees Fahrenheit or 27 degrees Celsius. As warm air rises rapidly from the surface of the ocean, its water vapor forms storm clouds and rain droplets, releasing latent heat of condensation. The heat warms the cool air and causes it to rise; the air is replaced by warm ocean air. The cycle repeats, causing continuous circulation of air from the surface to the atmosphere. This causes an exchange of heat that creates a pattern of wind.
- Winds at the ocean surface converge and push warm air upward, speeding the rising of air and the storm. Strong winds continue to blow and maintain the storm’s speed. The storm loses organization and weakens when there’s a difference in wind speeds. High-pressure air in the atmosphere removes heat from the rising air, further driving the hurricane’s growth. Wind speeds increase as high-pressure air is sucked into the low-pressure center of the storm. Hurricanes can last for more than two weeks over open water, but loses power on land or over cool waters, and its winds gradually die down.
- The movement of a hurricane is controlled by large-scale winds, the streams in the Earth’s atmosphere. Hurricanes rotate in different directions depending on their location.
- Tropical systems are steered westward by east to west winds, also known as trade winds. The earth’s rotation contributes to the acceleration that causes cyclonic systems to turn towards the poles in the absence of strong currents. This is known as the Coriolis Acceleration or Effect. When a storm’s center crosses the coastline, it is called landfall. The landfall area experiences only half the storm.
- The hurricane’s path of motion is referred to as a tropical cyclone’s track. Its general track around the high-pressure area is deflected significantly by winds moving towards the general low-pressure area to its north.
- Dissipation occurs when a hurricane moves over land, which deprives the storm of warm waters that power it, disorganizing it into low pressure areas. A hurricane remaining in one area too long uses all the warm surface water. It then draws up cooler water that cannot support the hurricane. Moving over water with temperatures below 26 degrees Celsius also causes a loss of strength. The formation of an outer eye wall ends the convection in the inner eye wall, causing the storm to lose power and stop. Artificial dissipation has been attempted, but tropical cyclones are too large.
- Answer: The Coriolis Effect
- Hurricanes are given names and categorized by the Saffir-Simpson scale, created in 1969 and used mostly in the Western Hemisphere.
- The Saffir-Simpson Hurricane Scale is a scale with a 1 to 5 rating on a hurricane’s intensity. Many factors such as potential property damage, amount of flooding expected along the coast, and particularly wind speed, determine the hurricane categories.
- To be considered a category one hurricane, the storm must have wind speeds of 74-95 mph with a storm surge generally 4-5 feet above normal sea level. Not much damage is done to homes and other buildings, unless they are unanchored, such as mobile homes. There is only minor coastal road flooding and damage. Hurricane Lili of 2002 and Hurricane Gaston of 2004 were category one hurricanes.
- Category two hurricanes have wind speeds of 96-110 mph with a storm surge generally 6-8 feet above normal. Some minor parts are damaged in homes and buildings, such as window and roofing material. More damage occurs in shrubbery and plants, and whole trees can completely get blown down. There are chances of 2-4 hour floods along the coast. Hurricane Frances of 2004 and Hurricane Isabel of 2003 were both category two hurricanes.
- Category three hurricanes must meet the wind speed of 111-130 mph with a storm surge of 9-12 feet above normal. Structural parts of buildings may be damaged. Floods can reach many miles inland, and street signs are completely demolished. It may even require the evacuation of low-lying residences along the coast. Category three hurricanes include Jeanne and Alex of 2004.
- To be a category four hurricane, a storm must have a wind speed of 131-155 mph with a storm surge generally 13-18 feet above normal. Extensive damage to building structures and roofs can be caused by category four hurricanes. All sorts of shrubbery and large trees are completely destroyed. Major damage can be done to low floors of coastal floors. Hurricanes Charley and Dennis were category four hurricanes.
- Category five hurricanes must have wind speeds greater than 155 mph with a storm surge of greater than 18 feet above normal. Complete homes can be washed away by the floods and winds. Low-lying residences within 10-15 miles of the shoreline must be massively evacuated. Hurricanes Katrina and Wilma of 2005 were considered deadly and put in category five.
- The Saffir-Simpson scale is based upon the Richter scale for hurricanes. Although the Saffir-Simpson scale categorizes hurricanes based upon wind speed and potential damage, it does not consider location and precipitation. This means that a lower category hurricane may actually do more damage than a higher categorized one.
- Tropical cyclones are named according to where they occur. Each section has a list of male and female names which are reused every six years. Hurricane names alternate between female and male, so if the first hurricane has a male name, it will be followed with a female name and vice versa. All the letters of the alphabet except Q, U, X, Y, and, Z are used when creating names. If all the names on a list have been used, storms are named after the letters of the Greek alphabet.
- Answer: Wind speed
- Hurricanes are capable of destroying buildings, large trees, and people. Between Category one and Category five hurricanes, the difference between the costs to repair this damage is between thousands of dollars to billions of dollars. To prevent further damage, scientists use a variety of tools to observe and predict hurricanes.
- A dissipating storm releases much rain, causing fatal mudslides and floods. Depending on the category of the hurricane, there can be a range of minimal damage to extensive damage. Buildings can be damaged and sometimes washed away by floods and winds. People can be killed or severely hurt by category four and five hurricanes. Often, evacuation is required to prevent deaths in an area.
- The cost of repairing damage done by a hurricane depends on its intensity, the location it hits, and response. Category one hurricanes cause little damage; therefore, there’s minimal cost for repair. Category two and three hurricanes cause a significant amount of damage. Trees are often uprooted, and structural damage to residences occurs. Evacuation near the coast is needed. This can range between thousands and hundred thousands of dollars. Category four and five hurricanes cause extensive damage. Homes can be wiped away, and people can be killed. To repair the damages done by Hurricane Katrina, 100 billion dollars were spent.
- To prepare for a hurricane, you should know about your community’s emergency plans, warning signals, evacuation routes, and locations of emergency shelters. You should also identify potential home hazards and know how to secure or protect them before the hurricane strikes. Electrical power, gas, and water supplies should be turned off before you evacuate. Structurally unstable building materials should be secured. After a hurricane strikes, it is important to discard any food that may have been touched by water. Don’t start any fuel-burning devices; there may be a chance that carbon monoxide could poison or kill you.
- When far from land, hurricanes are tracked by satellites with visible and infrared imagery that produce quarter- or half-hour updates. When near land, Doppler radar that has minute-by-minute is used. Doppler radars update on the storm's location and intensity. Small government aircrafts are sometimes flown into hurricanes.
- A hurricane's track is predicted by the position and strength of high- and low-pressure areas. High-speed simulation software produces forecast models of the track. The intensity of the storm is the least accurately predicted. Computer models are also used to predict rainfall.
- Although hurricanes mostly cause destruction, they are also known to have several beneficial effects. Hurricanes bring precipitation to hot and dry areas and moderate the global heat balance by moving warm air to cooler regions. The storm stirs up the waters of coastal fish breeding areas. It also spurs redevelopment of housing, which increases property value.
- Global temperatures have been increasing, which causes an increase in precipitation, thus in turn, causing an increase in hurricane intensity. Hurricanes thus have increased wind speeds and heavier precipitation because of the increase in water temperatures, which fuels hurricane growth. The annual number of storms has stayed about the same, but hurricane intensities have greatly increased.
- Answer: Satellite Doppler radar Airplanes
- The Great Hurricane of 1780 is known as the deadliest hurricane ever recorded, killing over 22,000 people! It was a category 4 hurricane, sustaining a wind speed of 150 mph. This hurricane first struck Barbados, and then continued on to other neighboring islands such as Martinique, Puerto Rico, and the Dominican Republic, and thousands perished in each place.
- Hurricane Ivan of 2004 reached a sustained wind speed of 165 mph, meeting the required speed for category 5. It originated in the Atlantic Ocean, and then moved over the Windward Islands over the Caribbean Sea. Its damage totaled to more than $19 billion.
- Hurricane Katrina of 2005 was the costliest and deadliest hurricane in the history of the United States. It was the sixth-strongest hurricane ever recorded in the world. Katrina was a category 5 hurricane and had maximum sustained wind speeds of over 175 mph. It started as a category 1 hurricane over the Bahamas and gradually made its way to category 5 over Louisiana and Mississippi. Over $81 billion was lost in destruction.
- Hurricane Paul of 1982 was the second deadliest East Pacific storm, with over 1,000 deaths. It was a category 2 hurricane with more than $70 million in damage and a maximum sustained speed of 110 mph. Paul first hit land in Central America, and it later moved north to the Baja California Peninsula. It caused major flooding and severe mudslides.
- Answer: Saturn Jupiter
- http://www.bt.cdc.gov/disasters/hurricanes/recovery.asp http://www.bt.cdc.gov/disasters/hurricanes/returnhome.asp http://miami.about.com/od/weather/a/hurricanenames.htm http://www.pewclimate.org/hurricanes.cfm http://en.wikipedia.org/wiki/Tropical_cyclone http://en.wikipedia.org/wiki/Tropical_cyclone_prediction_model http://en.wikipedia.org/wiki/Tropical_cyclone_rainfall_forecasting http://en.wikipedia.org/wiki/Eye_%28cyclone%29 http://www.aoml.noaa.gov/hrd/tcfaq/A1.html
- http://www.ntlib.nt.gov.au/tracy/advanced/Met/cyclones.html http://chuma.cas.usf.edu/~juster/volc1/world%20map.gif http://scifiles.larc.nasa.gov/text/kids/Problem_Board/problems/weather/hurricanebasics.html http://web.mit.edu/12.000/www/m2010/ http://en.wikipedia.org/wiki/Image:Typhoon_amber_concentric_eyewalls.gif http://en.wikipedia.org/wiki/Image:Low_pressure_system_over_Iceland.jpg http://en.wikipedia.org/wiki/Image:Global_tropical_cyclone_tracks-edit2.jpg http://www.ucar.edu/news/releases/2005/rainex.shtml http://www.vantagepointguides.com/how_to/hurricane.htm http://www.weatherwizkids.com/hurricane1.htm http://www.nhoem.state.nh.us/mitigation/section_iii.htm http://www.cartoonstock.com/ http://chattablogs.com/quintus/archives/2005_09.html http://www.nnvl.noaa.gov/cgi-bin/index.cgi?page=products&category=Year%202005%20Storm%20Events&event=Hurricane%20Katrina http://hosted.ap.org/specials/interactives/_national/hurricanes/index_categories.html
- http://www1.ncdc.noaa.gov/pub/data/images/hurr-rita-irloop.gif http://youtube.com/watch?v=rQ6aNNr4Qcc