Final project for ENVE 3320, Energy Analysis II, at the University of Georgia.

1. Energetics of the Multiday
2015 Carolina Flood
Dylan Munn
ENVE 3220
Environmental Engineering
dbmunn@uga.edu
The Weather Channel

2. Atmospheric Rivers Background
• On October 2-5, 2015, North and South Carolina received an
estimated 10 trillion gallons of rainfall
• An meteorological phenomenon called an atmospheric river
(AR) was to blame
• Atmospheric rivers are vital to the earth’s energy budget and
transport massive amounts of moisture poleward from the
tropical regions
• The average mass flow for the storm was 160,645,000 kg/s
• Studies done in the Pacific show AR mass flows up to 180,000,000 kg/s
• Equal to roughly 64 Olympic swimming pools per second
• Tend to occur at elevations of 2-3 km and may be thousands of
kilometers long

3. Energy Fluxes

4. • Water temperature in the Atlantic at the origin of the water vapor
was 30 °C and pressure at the surface was 1000 millibars
• Water vapor condensed at 2.5 km where the temperature was 25
°C and pressure was 800 millibars
• Cloud temperature was 21°C, pressure was 800 millibars, and
elevation was still 2.5 km as it began to form raindrops over SC
• Landed on the ground at a pressure of 1000 millibars and an
average temperature of 21°C
• Rain falls at 10 m/s
• Wind speed in the atmospheric river was 10 m/s
• The atmospheric river was 900 km long
• The mass flow was constant throughout the event
Assumptions

5. Where Energy Is Involved
• Evaporation requires an energy input for seawater to become
gaseous
• 𝑄 𝑣𝑎𝑝,𝑖𝑛 = 𝑚∆ℎ 𝑣𝑎𝑝 = 388.46 𝑇𝑊 Endothermic
• Upward transport of water vapor requires energy to overcome
gravity and extra energy is needed for lift through updrafts
• 𝐸𝑖𝑛 = 𝑚 ∆ℎ + 𝑔∆𝑧 = 578.97 𝐺𝑊 Endothermic
• Clouds form when condensation occurs, which in turn releases
energy into the atmosphere that was previously stored in the ocean
• 𝑄𝑐𝑜𝑛𝑑,𝑜𝑢𝑡 = 𝑚∆ℎ 𝑐𝑜𝑛𝑑 = 392.3 𝑇𝑊 Exothermic
• The transport of moisture over hundreds or thousands of kilometers
requires energy
• 𝐸 𝑜𝑢𝑡 = 𝑚(∆ℎ +
𝑉2
2
2
) = 2.679886 𝑇𝑊 Exothermic
• Energy was delivered to the ground through rainfall
• 𝐸 𝑜𝑢𝑡 = 𝑚 ∆ℎ −
𝑉1
2
2
+ 𝑔∆𝑧 = 3.94484 𝑇𝑊 Exothermic

6. • Heat needed for evaporation
• 𝑄 𝑣𝑎𝑝,𝑖𝑛 = 388.46 𝑇𝑊
• This is only .91% of the energy going toward the total evaporation occurring on earth
• 21.5 times the average world energy consumption at any given moment!!!
• Upward transport
• 𝐸𝑖𝑛 = 578.97 𝐺𝑊
• A little over half of the United States’ average amount of power in the grid system
• Heat released in condensation
• 𝑄𝑐𝑜𝑛𝑑,𝑜𝑢𝑡 = 392.3 𝑇𝑊
• 22 times the average world energy consumption at any given moment!!!
• Horizontal transport of moisture
• 𝐸 𝑜𝑢𝑡 = 2.679886 𝑇𝑊
• 1.5 times the amount of power generation the world gets from natural gas
• Rainfall
• 𝐸 𝑜𝑢𝑡 = 3.94484 𝑇𝑊
• Twice the amount of power generation the world gets from oil
Energy Comparisons

7. Before Flood and
Hurricane Joaquin
After Flood and
Hurricane Joaquin
Temperature Comparisons