By Daniel Brouse
August 13, 2023
Physicist Sidd Mukherjee said, “Wind and water flow forces scale as the square of velocity, so as flow speeds increase (say due to more intense heating or heavier rain) the damage scales as the square of the velocity. That force is proportional to density times square of velocity (v^2).”
The hall of historic Waiola Church in Lahaina and nearby Lahaina Hongwanji Mission are engulfed in flames along Wainee Street on Tuesday, Aug. 8, 2023, in Lahaina, Hawaii. (Matthew Thayer/The Maui News via AP)
In the Hawaii wildfires of August 2023, both wind and water flow forces contributed to the devastation. Hurricane Dora was at least 500 miles from Hawaii yet the wind forces impacted the fire in Maui. The winds were so strong that before the fire reached Lahaina extremely hot air blew over the town. The streets were so hot they burnt people’s feet trying to flee. The surface of everything became hot. Even after people jumped into the ocean, they said the debris in the water was too hot to float on.
The blast of hot air over Lahaina created the conditions for a flashpoint. A flashpoint is the temperature at which a particular organic compound gives off sufficient vapor to ignite in air. The entire town ignited so quickly that warning sirens could not be activated and people did not have time to escape.
In an unexpected twist, water flow forces also contributed to the chaos. How could water flow add to the fire emergency conditions? When people fled the heat and fire, they jumped into the sea. ABC news reported: Shawn Dougherty, of Lahaina, was among the hundreds of residents forced to flee the resort city when the wildfire began engulfing their homes.
Like others, Dougherty said his only means of survival was to jump into the ocean with his girlfriend, but while some found safety in nearby jetties, the rocks and coral tore up Dougherty’s body.
“At one point, it seemed like I might drown,” he told ABC News. “I’m a good swimmer, but the water was just really rough because of the wind and the turbulence.”
“By increasing the energy in the system, humans have increased flow volumes, masses and velocities leading to increased damage (and deaths.)” — Brouse and Mukherjee
From: Climate Change: The Equation / Brouse and Mukherjee (2023)