Atlantic hurricanes today are more likely to quickly become “major hurricanes” (Category 3 and above) than in the 1970s and 1980s, according to a new study released Thursday, which warns of increased risks for coastal communities.
The oceans, the main drivers of hurricanes, have warmed considerably in recent years, with the world’s seas absorbing more than 90% of the excess warming caused by human activity.
Previous research has shown that climate change creates conditions for more powerful storms that intensify more quickly and carry more water, although it has not been shown to increase their frequency.
The new study, published in the journal Scientific Reportsexamined the evolution of wind speeds during each Atlantic hurricane between 1970 and 2020. It concludes that all Atlantic storms — from the smallest to the fiercest — tend on average to intensify .
“This work shows that the rate at which hurricanes strengthen and the frequency with which they move from relatively weak storms to major hurricanes have increased significantly over just the past 50 years, even as we see increases “substantial changes in ocean surface temperatures due to human-caused warming,” explains study author Andra Garner of Rowan University in the United States.
His analysis shows that Atlantic hurricanes today are more than twice as likely to move from a relatively weak Category 1 to a Category 3 or stronger within 24 hours than in the 1970s and 1980s.
A trend particularly marked off the Atlantic coast of the United States and in the Caribbean Sea, but less notable in the Gulf of Mexico.
According to Andra Garner, this situation is particularly concerning for coastal communities, because the faster a storm intensifies, the more difficult it is to anticipate it.
Although the study did not specifically examine how hurricanes might further intensify as global warming continues, Mme Garner said the findings “should really serve as a cautionary tale about the urgency” of the situation.
“If we don’t radically change our behavior and quickly move away from fossil fuels to limit future ocean warming, I think we can expect this trend to become more and more extreme,” he said. the scientist.