Hurricane Risk to Northeast USA

The Northeastern coast of the USA could be struck by more frequent and more powerful hurricanes in the future due to shifting weather patterns, according to new research.

Hurricanes have gradually moved northwards from the western Caribbean towards northern North America over the past few hundred years, the study led by Durham University. The researchers suggest that this change in hurricane track was caused by the expansion of atmospheric circulation belts driven by increasing carbon dioxide emissions. New York and other major cities along the Northeast coast of the USA could come under increased threat from these severe storms and need to be better prepared for their potential impact. Researchers reconstructed hurricane rainfall for the western Caribbean dating back 450 years by analyzing the chemical composition of a stalagmite collected from a cave in southern Belize, Central America. When the hurricane history of Belize was compared with documentary hurricane records from places such as Bermuda and Florida, this information showed that Atlantic hurricanes were moving to the north rather than decreasing in total numbers. Although natural warming over the centuries has had some impact on shifting hurricane tracks, the researchers found a marked decrease in hurricane activity in the western Caribbean.
The researchers said that initial regional cooling of the Northern Hemisphere due to increased industrial aerosol emissions should have pushed the hurricane tracks southward since Industrialization. But they added that rising amounts of atmospheric carbon dioxide had overridden this effect by expanding the Hadley cell - a pattern of circulating air in Earth's tropical belt, pushing hurricane tracks further north, away from the western Caribbean towards the Northeastern USA. If future trends in carbon dioxide and industrial aerosol emissions continue as expected, hurricanes could shift even further northward, exacerbating the risk to the Northeast coast of the USA.

The study's lead author, Dr Lisa Baldini, in the Department of Geography, Durham University, said: "Our research shows that the hurricane risk to the Northeastern coast of the United States is increasing as hurricanes track further north".

Given the devastation caused by Hurricane Sandy it is important that plans are put in place to protect against the effects of similarly destructive storms which could potentially occur more often in the future.

Co-author Dr Amy Frappier, of the Geosciences Department, Skidmore College, USA, said the research showed Atlantic hurricanes were responding to warming.

"Aerosols from volcanoes and industrialization in the Northern Hemisphere have a cooling effect, which tend to shift moisture belts and hurricane tracks southward, closer to the equator.
"On the other hand, warming from more carbon dioxide in the air tends to expand Earth's tropical belt, pushing hurricane tracks further north away from the western Caribbean and towards the Northeastern US," Frappier said.

"However, increased sea surface temperatures also provide extra energy, potentially fueling larger storms. We therefore need to prepare for the effects of more frequent landfalls of larger storms along the Northeast coast of the United States and stronger storms impacting the Caribbean," Dr James Baldini, in Durham University's Department of Earth Sciences said.

https://www.sciencedaily.com/releases/2016/11/161123124441.htm