class #10: tuesday, july 20 hurricanes
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Class #10: Tuesday, July 20 Hurricanes. Chapter 15. hurricanes. Chapter 15. Fig. 15-CO, p. 410. Tropical Weather. Noon sun is always high, seasonal temperature changes small Daily heating and humidity = cumulus clouds and afternoon thunderstorms - PowerPoint PPT PresentationTRANSCRIPT
Class #10, Tuesday. July 20, 2010 1
Class #10: Tuesday, July 20Hurricanes
Chapter 15
Class #10, Tuesday. July 20, 2010 2
hurricanes
Chapter 15
Class #10, Tuesday. July 20, 2010 3Fig. 15-CO, p. 410
Class #10, Tuesday. July 20, 2010 4
Tropical Weather
• Noon sun is always high, seasonal temperature changes small
• Daily heating and humidity = cumulus clouds and afternoon thunderstorms
• Non-squall clusters, tropical squall line, tropical wave
• Seasons defined by precipitation as opposed to temperature
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Class #10, Tuesday. July 20, 2010 6
Anatomy of a Hurricane
• Intense storm of tropical origin with winds greater than 64kts; typhoon, cyclone, tropical cyclone
• Eye• Eye wall• Spiral rain band• Anticyclonic divergence• Latent heat
Class #10, Tuesday. July 20, 2010 7Fig. 15-2, p. 413
Class #10, Tuesday. July 20, 2010 8Fig. 15-3, p. 414
Class #10, Tuesday. July 20, 2010 9Stepped Art
Fig. 15-3, p. 414
Class #10, Tuesday. July 20, 2010 10Stepped Art
Fig. 15-3, p. 414
Class #10, Tuesday. July 20, 2010 11Stepped Art
Fig. 15-3, p. 414
Class #10, Tuesday. July 20, 2010 12Fig. 15-4, p. 415
Class #10, Tuesday. July 20, 2010 13Fig. 15-5, p. 415
Class #10, Tuesday. July 20, 2010 14Fig. 15-6, p. 415
Class #10, Tuesday. July 20, 2010 15
Hurricane Formation and Dissipation
The Right EnvironmentTropical waters with light wind26.5°C sea surface temperatures (June-November)Surface converge trigger (tropical wave)Coriolis effect: 5-20º latitude
The Developing StormCluster of thunderstorms around a rotating Low
pressureRelease of latent heat, divergence aloft
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Class #10, Tuesday. July 20, 2010 17
Class #10, Tuesday. July 20, 2010 18
Class #10, Tuesday. July 20, 2010 19Fig. 1, p. 419
Class #10, Tuesday. July 20, 2010 20
Hurricane Formation and Dissipation
• The Storm Dies Out– Cold water, land
• Hurricane Stages of Development– Tropical Disturbance– Tropical Depression (22-34kts)– Tropical Storm (35-64kts)– Hurricane (> 65kts)
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Class #10, Tuesday. July 20, 2010 22
Hurricane Formation and Dissipation
Topic: Hurricanes and Mid-latitude StormsHurricane warm core lowMid-latitude cold-core lowArctic hurricanesHurricane + upper level trough = mid-latitude
cyclone Hurricane movement
General track: west, northwest, northeastMuch variation
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Class #10, Tuesday. July 20, 2010 24
Class #10, Tuesday. July 20, 2010 25Stepped Art
Fig. 15-12, p. 421
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Class #10, Tuesday. July 20, 2010 27Fig. 15-14, p. 422
Class #10, Tuesday. July 20, 2010 28
Naming Hurricane and Tropical Storms
• Process has changed over the years:– Latitude and longitude– Letters of the alphabet– Alphabetical female names– Alphabetical, alternating female and male names– Retirement (Katrina, Camille)
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Devastating Wind, Storm Surge, and Flooding
• Highest winds on the eastern side of storm (wind + speed of storm)
• Swell• Storm surge on north side of storm (tide)• Coastal flooding• River flooding• Hurricane spawned tornadoes• Saffir-Simpson scale – 1 weakest, 5 strongest
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Class #10, Tuesday. July 20, 2010 31Table 15-1a, p. 423
Class #10, Tuesday. July 20, 2010 32Table 15-1b, p. 423
Class #10, Tuesday. July 20, 2010 33
Class #10, Tuesday. July 20, 2010 34Fig. 15-3, p. 414
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Class #10, Tuesday. July 20, 2010 36Fig. 2, p. 425
Class #10, Tuesday. July 20, 2010 37Fig. 3, p. 425
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Class #10, Tuesday. July 20, 2010 39
Some Notable Storms
• Camille 1969• Hugo 1989• Andrew 1992• Ivan 2004• Katrina 2005
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Some Notable Storms
Observation: Atlantic Hurricanes 2004-2005Abnormally warm ocean water and weak vertical
sheer allowed for high frequency of hurricanes Environmental Issue: Hurricanes in a Warmer
WorldNo clear answer, need more dataIntensity and frequency most likely to be
impacted.
Class #10, Tuesday. July 20, 2010 41Table 15-2, p. 426
Class #10, Tuesday. July 20, 2010 42Table 15-3, p. 427
Class #10, Tuesday. July 20, 2010 43Fig. 15-18, p. 428
Class #10, Tuesday. July 20, 2010 44Fig. 15-19, p. 428
Class #10, Tuesday. July 20, 2010 45Fig. 15-20, p. 429
Class #10, Tuesday. July 20, 2010 46Fig. 15-21, p. 429
Class #10, Tuesday. July 20, 2010 47Fig. 15-22, p. 430
Class #10, Tuesday. July 20, 2010 48Fig. 15-22, p. 430
Class #10, Tuesday. July 20, 2010 49Fig. 15-22, p. 430
Class #10, Tuesday. July 20, 2010 50Fig. 15-23, p. 430
Class #10, Tuesday. July 20, 2010 51Fig. 4, p. 431
Class #10, Tuesday. July 20, 2010 52Stepped Art
Fig. 4, p. 431
Class #10, Tuesday. July 20, 2010 53Fig. 15-24, p. 432
Class #10, Tuesday. July 20, 2010 54Fig. 15-25, p. 432
Class #10, Tuesday. July 20, 2010 55Fig. 15-26, p. 433
Class #10, Tuesday. July 20, 2010 56Fig. 15-27, p. 433
Class #10, Tuesday. July 20, 2010 57Fig. 5, p. 434
Class #10, Tuesday. July 20, 2010 58
Hurricane Watches, Warnings, and Forecasts
• Watch issued 24-48 hours before hurricane expected to make landfall
• Warning issued when storm expected to strike coast within 24 hours and probability of strike in a given location provided.
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Class #10, Tuesday. July 20, 2010 60Stepped Art
Fig. 15-27, p. 433
Class #10, Tuesday. July 20, 2010 61Fig. 6, p. 434
Class #10, Tuesday. July 20, 2010 62
Modifying Hurricanes
• Operation STORMFURY: seed clouds to create rain, weaken hurricane, and reduce winds; no conclusive evidence it was effective
• Oil or film on water to reduce evaporation and latent heat available to storms