London, 30 Dec (ONA) --- Climate change will expand the range of tropical cyclones, making millions more people vulnerable to these devastating storms, a new study found.
At present, these cyclones - or hurricanes as they are also known - are mainly confined to the tropical regions north and south of the equator, but researchers say that rising temperatures will allow these weather events to form in the mid-latitudes.
These areas include cities such as New York, Beijing, Boston and Tokyo.
The study has been published in the journal Nature Geoscience.
The scientists involved say their work shows by the end of this century, cyclones will likely occur over a wider range than they have for the past three million years.
When subtropical storm Alpha made landfall in Portugal in September 2020, the relatively small scale of damage caused by the cyclone made few headlines, but for scientists this was quite a momentous event.
Dr. Joshua Studholme, a physicist from Yale University said, “We hadn't observed this before. You had a traditional kind of mid-latitude storm, that sort of decayed, and in its decay, the right conditions for a tropical cyclone to form occurred, and that hadn't happened to Portugal before.”
Dr. Studholme is the lead author of this new study, which projects that a warming climate will see the formation of more of these types of storms in the mid-latitudes, where most of the world's population lives, and where most economic activity takes place.
He explained that as the world gets hotter, the difference in temperature between the equator and polar regions will decline, and this will impact the flow of the jet streams.
Normally, these high-altitude rivers of air act as a kind of border guard for hurricanes, keeping them closer to the equator.
"As the climate warms, that sort of jet stream activity that happens in the middle latitude, will weaken and in extreme cases split, allowing this sort of cyclone formation to occur."
The question of the impact of human induced climate change on hurricanes has been contentious in the past, but recent research suggests that the connections are becoming clearer.
Last August, the Intergovernmental Panel on Climate Change published the first part of its sixth assessment report, dealing with the science of a warming climate.
In relation to hurricanes and tropical cyclones, the authors said they had "high confidence" that the evidence of human influence has strengthened.
"The proportion of intense tropical cyclones, average peak tropical cyclone wind speeds, and peak wind speeds of the most intense tropical cyclones will increase on the global scale with increasing global warming," the Intergovernmental Panel on Climate Change (IPCC) said.
The new research published on Wednesday makes use of multiple strands of evidence to show that tropical cyclones in future are likely to occur over a wider range than previously thought.
The likely expansion of these storms poses a significant danger to the world, especially when the other impacts of warming come into play.
"These tropical cyclone changes, plus pronounced coastal sea level rise might compound potential societal impacts."
The authors argue that this course is not set in stone and that dramatic reductions in carbon emissions over the next decade particularly, could alter the outcome, the BBC news reported.