Atlantic hurricanes are more than twice as likely to quickly intensify into major storms in the past two decades compared to a comparable period in the late 20th century, according to research published Thursday in the journal Scientific Reports.
Author Andra Garner of New Jersey’s Rowan University analyzed more than 800 tropical cyclones originating in the Atlantic since 1971. She found that this century, storms grew from Category 1 minor storms to major hurricanes — those with winds of at least 111 miles per hour — within 24 hours 8.1 percent of the time. Comparatively, storms only intensified that quickly 3.2 percent of the time between 1971 and 1990.
Much of the intensification is due to warming ocean waters fueled by climate change, according to Garner. This warming largely overlaps with the intensification period she analyzed, with 0.6 degrees Celsius occurring in the period after 1980.
“Considering the role of warm upper ocean water and [sea surface temperatures] in the fastest TC [tropical cyclone] intensification, it is reasonable to expect that we may observe an increase in TC intensification rates that coincides with warming ocean temperatures in recent decades,” she wrote.
The findings have major implications for the U.S. in particular, where tropical cyclones are one of the costliest natural disasters along the East and Gulf coasts. Of the more than 160 climate disasters that caused in excess of $1 billion in damage to the U.S. over the last 10 years, 24 were tropical cyclones.
Among these were 2017’s Hurricane Maria, which had the highest death toll of any climate disaster in four decades and was the fourth-costliest in the same period. The storm went from a tropical storm to a Category 5 hurricane in about 48 hours.
During the same period, Garner also found that the likelihood of tropical cyclones quickly intensifying in the Gulf of Mexico has decreased, with a similar decrease occurring in the waters east of the Caribbean Sea. Likelihood has increased in not only the tropical eastern Atlantic and parts of the U.S. East Coast, but also the southern Caribbean.