Researchers also found the wind speeds in these storms could increase by as much as 20%, as well as a tremendous increase in the frequency of category 4 and category 5 storms — by more than 200% in some regions.
“Our results also re-emphasize that regions that currently have a (very) low risk could start to be really impacted by tropical cyclones under climate change,” Nadia Bloemendaal, a climate scientist at the University of Amsterdam and the lead author on the study , told CNN in an email. “We found it shocking to see the disproportionate amount of developing countries at risk for future climate change.”
The researchers used a statistical prediction system called STORM to generate 10,000 years of past and future climate conditions. They then used high-resolution wind speed maps to examine the future changes on a local scale, “which is so important for a risk assessment perspective,” Bloemendaal noted.
The region around Hong Kong and parts of the South Pacific have the highest likelihood of an increase in high-intensity storms, the scientists found.
Tokyo — the largest metropolitan area in the world with a population of around 38 million people — currently has a 4.6% chance annually of being impacted by an intense storm. In the future, scientists found that number jumps up to a 13.9% probability.
Another noticeable jump was for Hawaii. Currently, Honolulu has a 4% probability each year of being hit by an intense hurricane. In future years, that number will be 8.6% — more than doubling, as the study suggests.
The researchers said their results are likely due to the increase in sea surface temperature around the world. Ocean temperatures have warmed dramatically over the past several decades as a result of burning fossil fuels. The warmer water “will create more fuel for the storms to intensify,” Bloemendaal said.
The only regions where scientists didn’t see intense tropical cyclones doubling in the future was the Gulf of Mexico and the Bay of Bengal. The frequency of intense storms remained “essentially unchanged” in the study, Bloemendaal noted, because atmospheric conditions there will become less favorable for tropical storms in the future.
“The global climate models are projecting increased atmospheric stability over that region under future-climate conditions,” wrote Bloemendaal. “Due to this enhanced atmospheric stability, the overall frequency of tropical cyclones in the Gulf of Mexico is projected to decrease, as conditions have become more unfavorable for tropical cyclone development.”
But she also noted that when tropical storms do form in those regions, the warmer waters will provide extra fuel for the cyclone to intensify up to a category 3 or higher.
So while these scientists expect to see fewer storms overall in the Gulf of Mexico or Bay of Bengal, they will be extremely powerful and costly.
Hurricanes and typhoons are responsible for more monetary losses than any other natural disaster. In the last decade alone, the study notes, the United States has seen $480 billion in losses due to tropical storms and hurricanes.
Bloemendaal said that’s one of the reasons it’s more important than ever to be able to project where the strongest storms will occur in the future.
“Our results can help identify the locations prone to the largest increase in tropical cyclone risk,” Bloemendaal said in a statement. “Local governments can then take measures to reduce risk in their region, so that damage and fatalities can be reduced.”
Globally, 80 to 100 tropical cyclones form each year. But reliable records for these storms — which at one point could only be observed by ships or when they made landfall — only go back to the 1960s or so, as long as scientists have had weather satellites. This has made it difficult to predict long-term changes amid the climate crisis.
With this new research, scientists say the world will have a clearer picture into what the future holds for natures most destructive phenomenon worldwide.