HURRICANE STRUCTURE

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HURRICANE STRUCTURE

• Dr. Richard M. Yablonsky
• University of Rhode Island/GSO
• Hurricane Webinar Series 2012
• 28 February 2012, 700pm EST

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WHAT IS THIS???
lt 1 mile
Image courtesy of http//www.andovernet.com/
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WHAT IS THIS???
lt 1 mile
Image courtesy of http//www.andovernet.com/

• The Andover, KS TORNADO of April 26, 1991 (Wind
  250 mph)
• This is NOT a hurricane!!! This is NOT a
  hurricane!!!

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WHAT IS THIS???
10 miles
lt 1 mile
10 miles
Image courtesy of http//www.chaseday.com/
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WHAT IS THIS???

• A thunderstorm near
• Ardmore, OK
• This is NOT a hurricane!
• This is NOT a hurricane!
• This is NOT a hurricane!

10 miles
lt 1 mile
10 miles
Image courtesy of http//www.chaseday.com/
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OK Rich so you have lectured us on what a
hurricane IS NOT.Please stop teasing and tell
us what a hurricane IS!
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Definitions from United States National Hurricane
Center

• Hurricane A tropical cyclone in which the
  maximum sustained surface wind is 74 mph or more
  (NHC). OK, but what is a tropical cyclone?

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Definitions from United States National Hurricane
Center

• Hurricane A tropical cyclone in which the
  maximum sustained surface wind is 74 mph or more
  (NHC). OK, but what is a tropical cyclone?
• Tropical cyclone A warm-core, non-frontal,
  synoptic-scale cyclone, originating over tropical
  or subtropical waters, with organized deep
  convection and a closed surface wind circulation
  about a well-defined center (NHC). WHAT??? ?

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Hurricane Ivan on September 9, 2004
250 miles
Image courtesy of NOAA
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Hurricane Ivan on September 9, 2004
A thunderstorm in one of Ivans spiral bands
250 miles
Image courtesy of NOAA
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Hurricane Ivan on September 9, 2004
A thunderstorm in one of Ivans spiral bands
Eye (No Wind)
250 miles
Image courtesy of NOAA
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Hurricane Ivan on September 9, 2004
A thunderstorm in one of Ivans spiral bands
Eye (No Wind)
Eyewall Region of strongest winds
250 miles
Image courtesy of NOAA
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What about SIZE?
SIZE ? INTENSITY!
Courtesy of Brian Kabat US Air Force Academy
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What about SIZE?
SIZE ? INTENSITY!
Courtesy of Brian Kabat US Air Force Academy
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What about SIZE?
SIZE ? INTENSITY!
Courtesy of Brian Kabat US Air Force Academy
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What about SIZE?
Courtesy of Brian Kabat US Air Force Academy
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Largest Smallest Tropical Cyclones
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What about eyes? Here is Wilma
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And here is Isabel!
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Vertical slice through a hurricane
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Wind speed distribution
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Hurricanes Secondary Circulation
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Convection in the Atmosphere
COLD
COOL
Image courtesy of http//home.comcast.net/j2jens
en/
WARM
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Convection in the Atmosphere
COLD
COOL
Image courtesy of http//home.comcast.net/j2jens
en/
WARM
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Convection in the Atmosphere
COLD
The hot air parcel rises just like in a hot air
balloon!
COOL
Image courtesy of http//home.comcast.net/j2jens
en/
WARM
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Hurricanes are fueled by the ocean
URI team focus Understanding modeling
hurricane-ocean interaction
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Tropical vs. Extratropical Cyclones
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Extratropical Transition
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Definitions from United States National Hurricane
Center

• Hurricane A tropical cyclone in which the
  maximum sustained surface wind is 74 mph or more
  (NHC). Rich, you said that already!
• Tropical cyclone A warm-core, non-frontal,
  synoptic-scale cyclone, originating over tropical
  or subtropical waters, with organized deep
  convection and a closed surface wind circulation
  about a well-defined center (NHC). I think I get
  it now! ?

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Hurricanes Science and Society

• Learn more at
• www.hurricanescience.org