The U.S., Mexico and countries in the Caribbean are being battered by hurricane-induced ocean waves that have grown in areal size by 80 percent over the past 40 years, a study released earlier this year has found.

The first global trend study of its kind, led by Hohai University in China, investigated the long-term changes in both the height and surface area coverage of global tropical cyclone ocean surface waves since 1979.

Published in Nature Communications, the study found the coverage area of ocean waves generated by tropical cyclones increased by nearly 20 percent (167,000 km2, about the size of Florida State) per decade in the North Atlantic Ocean.

Globally, the area of ocean waves increased by 6 percent per decade from 1979 to 2022. The maximum height of ocean waves caused by tropical cyclones grew by 3 percent per decade.

Dr. Xiangbo Feng, a University of Reading tropical storm expert who co-authored the study, said, “The rapid growth of tropical cyclone waves over recent decades is extremely worrying given their immense danger to communities, businesses and ecosystems. Our results show that the threat from their waves is escalating fast across the globe.”

“Hurricanes whip up huge, devastating waves over that quickly swamp coastlines. Their long, rolling swells also travel hundreds of miles, flooding distant areas, so coastal towns and vessels urgently need to prepare better defenses—especially in the Americas—to avoid damage from these extreme waves,” he added.

Tropical cyclones, also known as hurricanes in the North Atlantic and East Pacific or known as typhoons in the West Pacific, are rapidly spinning storms that form over warm ocean waters in tropical regions.

As tropical cyclones move across the ocean, their strong winds stir up large waves from the storm’s center.

The highest tropical cyclone-induced ocean wave height ever recorded (defined as the mean height of the highest one-third of waves measured from trough to crest) was 24 m, caused by Typhoon Krosa in 2007 in the West Pacific.

In addition to wave heights and area coverage rising, the study also found that the total wave energy produced by tropical cyclones has increased by 9 percent per decade globally.

The largest increase of 30 percent per decade was found in the East Pacific and North Atlantic.

These increases pose a greater danger to North American and Caribbean countries located by the North Atlantic Ocean where the frequency of major hurricanes has been increasing in the past several decades.

The researchers anticipate that ocean wave size (defined by the overall height and the footprint area) is likely to substantially increase in the future due to a combination of factors, including tropical cyclone intensity, size and translation speed (how fast tropical cyclones move across the Earth’s surface).

The authors suggest more research is needed to understand the multiple effects of global warming on extreme wave height.

As tropical cyclone waves become higher and more frequent in this region, the new study emphasizes the need for proactive preparation in coastal regions vulnerable to tropical storms.

Larger areas will endure damaging winds and high waves when tropical cyclones make landfall.

Jian Shi et al, Global increase in tropical cyclone ocean surface waves, Nature Communications (2024).