Download Physics and Challenges of Tropical Cyclones

Physics and Challenges of
Tropical Cyclones
Ashley Bernheisel
24 February 2014
Discussion Outline
 Why this topic?
 Difference between a
cyclone, hurricane,
and typhoon
 Physics of Cyclones
 Challenges
 Can we destroy
tropical cyclones?
 Conclusion
 References
Why this topic?
Property of Ashley Bernheisel
Property of Carl Miller
Property of Ashley Bernheisel
Property of Carl Miller
Cyclone, Hurricane, Typhoon?




Rotating storm (“cyclonic”)
stretching 100-1000 km
horizontally and 15 km
vertically
All the same phenomenon,
different locations
 Cyclone: South Pacific,
Indian Ocean
 Hurricane: Atlantic,
Northeast Pacific
 Typhoon: Northwest
Pacific
Counter clockwise rotation
in the Northern
Hemisphere
Clockwise rotation in the
Southern Hemisphere
http://www.ucar.edu/news/features/hurricanes/htc_desc.htm
http://talkingpointsmemo.com/news/photos-over-100-dead-as-typhoonrips-through-philippines
How is a cyclone formed?
 Tropical disturbance
 Energy transferred
from oceans to
atmosphere
 Air becomes more
buoyant
 Coriolis Effect
 Drop in atmospheric
pressure
 7% of tropical
disturbances turn into
tropical cyclones
http://www.abc.net.au/storm/exposure/thirteen.htm
http://www.nicerweb.com/sketches/video/B
BC-WildPacific/
http://www.soest.hawaii.edu/met/Faculty/busin
ger/poster/hurricane/
Diagram of Cyclone Formation
http://c9geonaturalhazards.wikispaces.com/Caitlin.m
Basic Concepts
 Why warm
waters?
 How does a
tropical
cyclone cool
the ocean
surface?
http://www.wunderground.com/blog/Weather456/tropical-cyclonesphysics-energetics-and-mechanics
Basic Concepts - 2
 Why is moist air
lighter than drier air at
the same temperature?
 What causes the warm
core in the cyclone?
http://www.wunderground.com/blog/Weather456/tropical-cyclonesphysics-energetics-and-mechanics
http://www.aoml.noaa.gov/hrd/tcfaq/A17.html
Basic Concepts - 3
 What causes the
pressure heights
to fall in a
tropical
cyclone?
 Types of energy
associated with
tropical
cyclones?
http://www.wunderground.com/blog/Weather456/tropicalcyclones-physics-energetics-and-mechanics
The Mature Cyclone: A Natural Carnot Heat
Engine
http://eaps4.mit.edu/faculty/Emanuel/
Maximum Wind Speed
 Equation:
http://www.columbian.com/news/2013/nov/10/typhoo
n-deaths-climb-into-thousands-in-philippines/
Can We Destroy Tropical Cyclones?
 STORMFURY Project –
Silver Iodide
 Placing a substance on
the ocean surface? (Soot)
 Cooling the surface
waters?
 Altering heat balance
using high altitude
particles?
 Seeding them with
hygroscopic particles?
http://www.aoml.noaa.gov/hrd/hrd_sub
/sfury.html
Challenges
 International Effort
 Understanding Effects:
1. Movement,
2. Genesis and Intensity
Change
3. Ocean-Biogeochemistry
Interaction
4. Response and feedback to
climate change
5. Tectonics, Geomorphology,
Seismology
 Numerical Weather
Predictions
 McNoldy Statement
http://www.cnn.com/2013/11/09/world/iyw-how-tohelp-typhoon-haiyan/
http://www.dodlive.mil/index.php/2009/11/armed-withscience-the-joint-typhoon-warning-center-tropical-weathersupport/
Conclusion
http://www.japanfocus.org/site/view/2763
 Tropical Cyclone is generic
term for a cyclonic storm
 Formation needs the right
conditions
 Ideal cyclone is like a Carnot
Heat Engine
 Maximum Wind Speed
 We have not found a way to
destroy tropical cyclones
 Many challenges ahead
 Tropical Cyclones have an
enormous amount of energy
References
Emmanuel, Kerry. “Lectures on Tropical Cyclones”. 13 April
1998. http://wind.mit.edu/~emanuel/geosys/node1.html
Emmanuel, Kerry. “The Theory of Hurricanes.” Annual
Reviews Fluid Mechanics. 1991.
http://www.math.nyu.edu/caos_teaching/hurricanes/em
anuel91.pdf
“Frequently Asked Questions”. NOAA: Hurricane Research
Division. 2014.
http://www.aoml.noaa.gov/hrd/tcfaq/tcfaqHED.html
“How do tropical cyclones form?” . 10 October 2012.
http://blog.cyclonecenter.org/2012/10/10/how-dotropical-cyclones-form/
Rawlins, Cavin. “Tropical Cyclones”. Weather Underground.
25 October 2009.
http://www.wunderground.com/blog/Weather456/tropic
al-cyclones-physics-energetics-and-mechanics
Questions?
http://rs.resalliance.org/2007/10/29/global-tropical-cyclone-tracks/