5:45 pm ET, August 30, 2023
Warmer ocean temperatures may have increased Italia’s destructive power by 40 to 50%, the scientist says
From CNN’s Rachel Ramirez
Before making landfall as a Category 3 storm, Hurricane Italia went through a significant period of rapid intensification from Tuesday night into Wednesday morning. Its maximum sustained winds increased to 55 miles per hour in just 24 hours.
To draw from the vast pool of warm ocean water, the storm converts that heat into wind power. In addition to storm surge and heavy rain, strong winds are one of the most dangerous aspects of hurricanes.
In 1987, Kerry Emanuel, a professor of atmospheric sciences at the Massachusetts Institute of Technology, predicted that for every 1°C increase in tropical ocean temperatures, hurricane wind speeds are expected to increase by about 5%.
Tom Knutson, a senior scientist at the National Oceanic and Atmospheric Administration, told CNN that 4 to 5% was “toward the high end of the range across studies.” Some studies like the one written by Knutson showed an increase of 3.75%.
But that increase — however small — can dramatically increase a hurricane’s damage potential, Masters explained.
“A 4-5% increase in hurricane winds may not seem like a big deal, but hurricane damage increases exponentially with increased winds,” Masters wrote. “For example, according to NOAA, a Category 2 hurricane with 100 mph winds can cause 10 times the damage of a Category 1 hurricane with 75 mph winds. This includes damage not only from wind, but also from storm surge, inland flooding and tornadoes.