Hurricane Thermodynamics

Alex MacIntoshCam MateusSteve Lazar

Costliest Hurricanes

1. Katrina – 2005 – $81 Billion2. Andrew – 1992 – $26.5 Billion3. Wilma – 2005 – $20.6 Billion4. Charley – 2004 – $15 Billion• Difficult to study: immense power• About 48 of 80 tropical cyclones qualify

in terms of intensity

http://www.nhc.noaa.gov/Deadliest_Costliest.shtml

Physical Structure

• Storms form in the tropics

• Three main parts– The eye– Eyewall– Rainbands

• Axisymmetric Vortex• Hydrostatic and

Rotational Balancehttp://www.srh.noaa.gov/jetstream/tropics/tc_structure.htm

Carnot Engines

• Thermodynamic disequilibrium

• Four Sequences– Isothermal Expansion– Adiabatic Expansion– Isothermal

Compression– Adiabatic

Compression http://en.wikipedia.org/wiki/Atmospheric_thermodynamics

Equations

• Efficiency of Carnot Engine• Carnot’s Theorem to

predict maximum wind speed

1

2

1

2 11TT

QQ

hhCC

TTT

VD

hMax

*

2

212

dtdQ

dtdW

dtdQ 21

dtdQ

TTT

dtdW 10

2

21

Climate Change

• Greenhouse gases and effects on hurricanes

• Carnot’s Theorem: Temperature difference and intensity of hurricane– Adiabatic expansion increased– Greater wind velocity

How Temperature Variation Effects Wind Velocity

When T1 = 25C, the Vmax is ~ 5.85 m/sWhen T1 = 30C, the Vmax is ~ 8.34 m/s

This is a stunning 50% increase in the wind velocity!

hhCC

TTT

VD

hMax

*

2

212

How?

• Apply a cryogenic coolant– Nitrogen gas– Carbon Dioxide– Air– Water

• Transport and deliver coolant using – Plane– Ship – BargeRemotely Controlled?

Thermal Updrafts

Strongest Thermal UpdraftAt the down tilt right region of Hurricane

Apply Coolant There

From Nat. Oceanic and Atmospheric Administration http://celebrating200years.noaa.gov/historymakers/Smagorinsky/hurricane_emily650.html

What?

• Coolant does:– Decreases updraft temperature– Increase wind shear w/ large solid coolant

pieces• Higher the wind shear---weaker the storm

From www.fema.gov

Clausius-Clapeyron

Citations

• Emanuel, K.A., The Theory of Hurricanes. Annu. Rev. Fluid Mech., 23 (1991) 179-196

•Tropical Cyclone Structure. [cited November 27, 2008]; Available from: http://www.srh.noaa.gov/jetstream/tropics/tc_structure.htm

•Kondepudi, Dilip. Introduction to Modern Thermodynamics. John Wiley & Sons, Ltd, 2008.

•Emanuel, K.A., Tropical Cyclones. Annu. Rev. Earth. Planet. Sci., 31 (2003) 75-104.

•Atmospheric thermodynamics. [cited November 26, 2008]; Available from: http://en.wikipedia.org/wiki/Atmospheric_thermodynamics.

•Mooney, C. The Truth About the 2007 Atlantic Hurricane Season. 2007 [cited October 26, 2008]; Available from: http://www.thedailygreen.com/environmental-news/blogs/hurricanes-storms/7889.

•O’Keefe, D.R., Hurricane Abatement Method and System, U.P.T. Office, Editor. 2007: USA