West News Wire: According to a recent study, changes in air patterns brought on by global warming will undoubtedly increase the number and intensity of hurricanes that strike the east and Gulf coasts of the United States, particularly Florida.
The study published on Friday in the journal Science Advances focuses on the key issue of where hurricanes are going, whereas previous studies have projected how human-caused climate change will likely alter the frequency, severity, and wetness of tropical storms.
According to research main author Karthik Balaguru, a climate scientist at the Pacific Northwest National Laboratory, it all comes down to expected changes in steering currents.
According to Balaguru, “they’re kind of pushing the storms closer to the U.S. along every coast.” Along the Gulf of Mexico, the steering currents flow from south to north; on the East Coast, the typical west-to-east steering is lessened considerably and can be more east-to-west, he said.
Overall, in a worst-case warming scenario, the number of times a storm hits parts of the U.S. coast in general will probably increase by one-third by the end of the century, the study said, based on sophisticated climate and hurricane simulations, including a system researchers developed.
The central and southern Florida Peninsula, which juts out in the Atlantic, is projected to get even more of an increase in hurricanes hitting the coast, the study said.
Climate scientists disagree on how useful it is to focus on the worst-case scenario as the new study does because many calculations show the world has slowed its increase in carbon pollution. Balaguru said because his study looks more at steering changes than strength, the levels of warming aren’t as big a factor.
The study projects changes in air currents traced to warming in the equatorial eastern Pacific Ocean, just off the coast of South America. Climate change is warming different parts of the world at different rates, and models show the eastern Pacific area warming more quickly, Balaguru said.
That extra warming sets things in motion through Rossby waves, according to the study atmospheric waves that move west to east and are connected to changes in temperature or pressure, like the jet stream or polar vortex events.
“I like to explain it to my students like a rock being dropped in a smooth pond,” said University of Albany atmospheric scientist Kristen Corbosiero, who wasn’t part of the study. “The heating is the rock and Rossby waves are the waves radiating away from the heating which disturbs the atmosphere’s balance.”
It doesn’t factor in where storms are born, which is important, and the study assumes a global trend toward more El Nino events, said Jhordanne Jones, an atmospheric scientist at the National Center for Atmospheric Research and Purdue University’s Climate Extreme Weather Lab. Most climate simulations project more El Ninos, which is a natural warming of the central Pacific that alters weather worldwide and dampens Atlantic hurricane activity. But recent observations “suggest a more La Nina- like state,” she said.