Just-in-Time Lecture

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www.pitt.edu/super/
Just-in-Time Lecture Hurricane
Ali Ardalan, Ronald E. LaPorte,
Eugene Shubnikov,
Faina Linkov, Mehdi Russel Eric K. Noji
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What is the Disaster
Supercourse?
http//www.pitt.edu/super1
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Mission Statement The Global Health Network
Disaster, Network for Hurricane is designed to
translate the best possible scholarly information
from leading researchers to educators worldwide.
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What is a JIT lecture?
http//www.pitt.edu/super1
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• Lecture objectives
• To provide the best possible
• information about the science of
• Hurricane
• To learn how the science can help
• prepare us for primary secondary
• prevention consequences of Hurricane

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Origin of the word Hurricane
Carib god Hurican was derived from Mayan god
'Hurakan', one of their creator gods, who blew
his breath across Chaotic water brought forth
dry land later destroyed men of wood with a
great storm and flood .
HURRICANE derived from Hurican, the Carib
god of evil !! Glossary of Meteorology
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• Hurricane at a glance!
• A tropical storm with 74 mph speed
• winds Hurricane winds blow in a large
• spiral around a relative calm center
• known as the Eye."
• The Eye" is generally 20 to 30 miles
• wide the storm may extend
• outward 400 miles.

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• Hurricane at a glance!
• A single hurricane can last for
  
• gt 2 weeks over open waters
• Peak months August September
• Hurricane season 1st June-30th
• November

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• Basic terminology in hurricanes
• Sustained wind
• Long lasting wind, reporting based on
• 1 min average time in Atlantic NE Pacific
• 10 min average time in rest of the world
• Maximum sustained wind
• The highest 1 min Surface winds within
• system circulation

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• Basic terminology in hurricanes
• Gusts
• 3-5 seconds wind peak
• 20-25 gt 1 min sustained wind

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• Basic terminology in hurricanes
• Storm surge
• Onshore rush of sea or lake water caused by
• the high winds associated with a land falling
• cyclone and secondarily by low pressure of
• the storm

Be careful Storm surge Storm tide are
different !
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• Hurricane Anatomy
• EYE
• Centre of a hurricane characterized by a
• roughly circular area of light winds
• rain-free skies lowest pressure
• Developed when the maximum sustained
• wind speeds exceed 78 mph
• Ranged size 5-60 miles (20 miles in average)
• Shrinking the eye, intensifying the storm

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• Hurricane Anatomy
• EYE WALL
• Organized band of convection
• surrounding eye or the centre
• Contains cumulonimbus clouds,
• severest thunderstorms, heaviest
• precipitation and strongest winds

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• Hurricane Anatomy
• Spiral rain bands
• Large bands of clouds precipitation spiral
• from the eye wall

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• Hurricane Anatomy
• Moat
• Region between the eyewall an outer
• rainband, such as a secondary eyewall
• rainband
• Relatively light rain region between
• rainband eyewall

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Environmental Condition for tropical cyclone
formation

• Warm ocean waters of at least 26.5 C (80 F)
• Warm, humid air
• Relatively moist layers near mid-troposphere (5
  km)
• Minimum distance of at least 500 km from equator

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Environmental Condition for tropical cyclone
formation

• Pre-existing near-surface disturbance with
  sufficient vorticity convergence
• Low values (less than 23 mph) of vertical wind
  shear between the surface the upper troposphere

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Sequence of Hurricane formation
Tropical Disturbance
1
Tropical Depression
2
Tropical Storm
3
Hurricane
4
4
3
1
2
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• Hurricane term
• REGIONALLY specific names for a strong
• Tropical cyclone"

Tropical cyclones with max. sustained winds of
less than 39 mph with close circulation

• Tropical Depression

• Tropical Storm

Tropical cyclones with max. sustained winds of
39-73 mph

• Hurricane
• Typhoon
• Severe tropical
• cyclone
• Tropical cyclone

Tropical cyclones with sustained winds of 74 mph
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REGIONALLY names of Tropical cyclones with
winds of 74 mph

• Hurricane
• N Atlantic Ocean, NE Pacific Ocean E of
• dateline, or S Pacific Ocean E of 160E
• Typhoon
• NW Pacific Ocean W of dateline

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REGIONALLY names of Tropical cyclones with
winds of 74 mph

• Severe tropical cyclone
• SW Pacific Ocean W of 160E or SE Indian
• Ocean E of 90E
• Severe cyclonic storm
• The North Indian Ocean
• Tropical cyclone
• The Southwest

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More details about Hurricane formation (1)
Wind blows the clouds clockwise start pulling
up ocean water. Then the bottom water moves
counterclockwise.
Air sinks into the centre (the eye).
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More details about Hurricane formation (2)
Wind spins around the eye, where hurricane is the
strongest.
As the wind flows higher it becomes weaker and
flows clockwise.
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• Hurricane death
• A mature hurricane is a well-oiled
  meteorological
• machine, but disruption of the processes that
• drive storm (interaction with land or colder
  air
• feeding in) will begin to destroy storm,
  the
• disintegration of a hurricane is quick
  dramatic.
• Important death factors
• Westerly winds
• Going over land as there is warm water

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• Cape Verde-type hurricanes
• Atlantic basin tropical cyclones fairly close
• (lt1000 km) of Cape Verde Islands then
• become hurricanes before reaching Caribbean
• Typical months August September
• Frequency Ranged 0-5, with an average of 2

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• Hurricane/Tropical Cyclone
• Intensity Scales
• Atlantic hurricanes ranking
• (Saffir-Simpson hurricane intensity
• scale)
• Australian tropical cyclones ranking

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Saffir-Simpson hurricane intensity scale
Damage descriptor Storm surge Minimum surface pressure Max. sustained 1 min. wind speed Category
Damage descriptor m mb mph Category
Minimal 1.0-1.7 gt 980 74-95 1
Moderate 1.8-2.6 979-965 96-110 2
Extensive 2.7-3.8 964-945 111-130 3
Extreme 3.9-5.6 944-920 131-155 4
Catastrophic 5.7 lt 920 156 5
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Australian tropical cyclones ranking
Effects Wind Category
Negligable house damage. Damage to some crops, trees and caravans. Draft may drag moorings. Strongest gust less than 125 km/h 1
Minor house damage. Significat damage to signs, trees and caravans. Heavy damage to some crops. Risk of power failure. Small craft may break moorings Strongest gust 125 - 170 km/h 2
Some roof and structural damage. Some caravans destroyed. Power failure likely. Strongest gust 170 - 225 km/h 3
Significant roofing loss and structural damage. Many caravans destroyed and blown away. Dangerous airborne debris. Widespread power failure. Strongest gust 225 - 280 km/h 4
Extremely dangerous with widespread destruction. Strongest gust More than 280 km/h 5
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• Factors contributing in hurricane damages
• Distance from zone of maximum winds
• How exposed the location is
• Building standards
• Vegetation type
• Resultant flooding

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• Major hurricane Intense hurricane
• Max. sustained surface winds At least 111 mph
• Category 3,4 and 5 on Saffir-Simpson scale
• Cause gt 83 of damages in the USA even
• though account for only 21 of tropical
• cyclone landfalls

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• HURRICANE WARNING
• Added to a hurricane advisory that sustained
  winds
• of 74 mph associated with a hurricane are
• expected in a specified coastal area within 24
  h.
• Can remain in effect when dangerously high water
  or
• a combination of dangerously high water
• exceptionally high waves continue, even though
  
• winds may be less than hurricane force.
• Is used to inform the public and marine
  interests of
• the storm's location, intensity, and movement.

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• HURRICANE WATCH
• An announcement added to a hurricane
• advisory that hurricane conditions pose a
• possible threat to a specified coastal area
• within 36 hours.
• Is used to inform the public and marine
• interests of the storm's location, intensity,
• movement.

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• Subtropical cyclone
• Low-pressure system in tropical or subtropical
  latitudes cyclones
• Radius of max. winds farther out (on order of
  60-125 miles from
• the centre) than what is observed for purely
  tropical systems
• Max. sustained winds no stronger than 74 mph
• Classified by max. sustained surface winds
• lt 37 mph Subtropical depression
• 38 mph Subtropical storm

Transform to tropical cyclones in many times
then Hurricane, like Hurricane Florence, Nov 1994
!
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USGS
Slide Dr. Tom Songer
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Hurricane direct related health hazard
High winds
Storm surge
Flooding
Tornados

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Hurricane direct related health hazard High
Winds
Energy of winds wind velocity squared (E V2)
2 times wind speed 4 times destructive energy

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Hurricane direct related health hazard High
Winds

• Intensity of a landfalling hurricane is
• expressed in terms of categories that relate
• wind speeds potential damage
• (Saffir-Simpson Scale)
• Category 4 hurricane (131-155 mph winds)
• causes 100 times damage of Category 1 storm!

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Hurricane direct related health hazard
Rainfall Flooding

• Responsible for 59 of the
• deaths associated with tropical
• cyclones in the US
• Intense rainfall is not directly related to
• wind speed. Some of the greatest rainfall
• amounts occur from weaker storms that
• drift slowly or stall over an area.

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Hurricane direct related health hazard Rainfall
Flooding NHC Preventive recommendations

• When you hear hurricane, think inland flooding
• Determine whether you live in a potential flood
  zone
• If advised to evacuate, do so immediately
• Keep abreast of road conditions through the news
  media
• Move to a safe area before access is cut off by
  flood water
• Do not attempt to cross flowing water. As little
  as 6 inches
• of water may cause you to lose control of your
  vehicle
• Develop a flood emergency action plan
• Have flood insurance

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Hurricane direct related health hazard Storm
Surge

• 50 - 100 miles wide
• 4 - 6 feet for a minimal hurricane to
• gt 20 feet for the stronger ones

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Hurricane direct related health hazard Tornado

• More intense hurricane, greater tornado threat
• 10 of hurricane related death in the US
• Mostly within 24 hours after
• hurricane landfall
• Mostly within 150 miles
• of the coastline

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Hurricane direct related health hazard Tornado

• Occurrence during morning afternoon rather
• than evening or night due to need for heat
  source
• The Gulf of Mexico hurricanes produce more
• tornadoes than Atlantic storms
• Mostly occur within 30 miles of center of
  cyclone
• Can reach up to 300 mph at a forward speed
• of 60 mph and are usually 100-300 yards wide

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Hurricane History of death economical damages
1990-2003
Damage () Death
26.5 billion 23 Hurricane Andrew 1992
500 million 30 Tropical Storm Alberto 1994
3 billion 59 Hurricane Opal 1995
40 million 9000 Hurricane Mitch 1998
3-6 billion 50-56 Hurricane Floyd 1999
225 million 24 Hurricane Keith 2000
5 billion 41 Tropical Storm Allison 2001
31 Hurricane Iris 2001
3 billion 17 Hurricane Isabel 2003
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• Hurricane Preparedness, Before Hurricane Season
  Stars (8 points)
• 1) Plan an evacuation route
• Contact the local emergency management office or
  Red Cross chapter, ask for the community
  hurricane preparedness plan, including
  information on the safest evacuation routes
  nearby shelters.
• 2) Learn safe routes inland
• Be ready to drive 20 to 50 miles inland to
  locate a safe place.
• Have disaster supplies on hand Flashlight
  extra batteries, Portable, battery-operated radio
  extra batteries, First aid kit manual,
  Emergency food water, Non-electric can opener,
  Essential medicines, Cash credit cards, Sturdy
  shoes.

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• Hurricane Preparedness, Before Hurricane Season
  Stars (8 points)
• 3) Make arrangements for pets
• Pets may not be allowed into emergency shelters
  for health space reasons, so contact your
  local humane society for information on local
  animal shelters
• 4) Make sure that all family members know how to
  respond after a hurricane
• Teach family members how when to turn off gas,
  electricity, water
• Teach children how when to call police, or
  fire department which radio station to tune to
  for emergency information

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• Hurricane Preparedness, Before Hurricane Season
  Stars (8 points)
• 5) Protect your windows
• Permanent shutters are the best protection. A
  lower-cost approach is to put up plywood panels.
  Use 1/2 inch plywood - marine plywood is best -
  cut to fit each window. Remember to mark which
  board fits which window.
• Pre-drill holes every 18 inches for screws. Do
  this long before the storm
• 6) Trim back dead or weak branches from trees.7)
  Check into insurance

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• Hurricane Preparedness, Before Hurricane Season
  Stars (8 points)
• 8) Develop an emergency communication plan.
• In case family members are separated from one
  another during a disaster (a real possibility
  during the day when adults are at work children
  are at school), have a plan for getting back
  together.
• Ask an out-of-state relative or friend to serve
  as the "family contact." After a disaster, it's
  often easier to call long distance. Make sure
  everyone in the family knows the name, address,
  and phone number of the contact person.

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Make sure you are prepared!
http//www.fema.gov/hazards/hurricanes/whatshouldi
do.shtmbefore
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References
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We wish to express our warm thanks to GDHNet
faculties and all groups that contributed their
valuable materials.