Hurricanes will grow stronger as the climate heats. More of them will spin up into major storms. It’s not only the worst cyclones that are getting worse. Research has shown that weak tropical cyclones (including tropical storms) are becoming more severe over time.
The study, published Wednesday in the journal Nature, uses data collected by thousands of scientific instruments scattered across the world’s oceans. The water is swollen by tropical cyclones, which can cause ocean currents to speed up as they move through. These currents can be measured by scientists to determine the wind speeds of a storm.
This is one of the first studies to use ocean measurements directly, instead of satellite data, in order to track changes over time in the intensity and strength tropical cyclones.
This is important, the authors state. Satellites have been invaluable for tracking hurricane activity around the world over the last 40 years–but they have their limitations. Satellites can be used to show scientists where storms are forming and where they’re moving but they’re not as reliable in determining the storm’s intensity.
Scientists often use aircraft missions to get up-close information about hurricanes’ wind speeds and other characteristics. It’s impossible to collect this kind of data for every cyclone that forms in the world.
This makes it difficult for long-term trends to be tracked in hurricane intensity.
However, previous studies have attempted this and there are indications that tropical storms are becoming stronger over time. A 2020 study found that the proportion of hurricanes that turn into major storms–a Category 3 or higher–has grown over the last few decades.
Climate models suggest that hurricanes will continue to strengthen as the planet warms.
The new study adds to the evidence that tropical storms are becoming stronger. According to ocean measurements, tropical cyclones are likely increasing at an average rate of around 1.8 meters per year. This study shows that storms around the globe are experiencing a strengthening trend.
The study has one major drawback: the findings are not reliable for weak tropical cyclones such as Category 1 hurricanes and tropical storms. This is because there hasn’t been enough data to determine if stronger storms have ever occurred.
But in a comment on the new research, also published Wednesday in Nature, atmospheric scientist Robert Korty says he suspects the findings are probably true for stronger storms as well. He also notes that the measurements in this study are only snapshots of time. These storms could have been weak at the time they passed over ocean sensors, but would eventually intensify into larger storms.
He writes that “some of these data correspond to stronger storms.”
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2022. E&E News delivers vital news to professionals in the energy and environment industries.