Sharks... to Improve Hurricane Forecasting - Sarmad
From the killer shark in the film “Jaws” to the predators hurled by hurricanes in “Sharknado,” movies have long portrayed these fish as symbols of summer fear.
But when a shark swims through waters off the U.S. East Coast, it may not be hunting alone; it could also be gathering data that help scientists predict the potential intensity of a hurricane before it makes landfall.
Researchers at the University of Delaware are testing whether sharks can serve as mobile ocean data observers, providing near-real-time information about oceanic, atmospheric, and climate models by carrying sensors that measure ocean conditions.
These sensors are small electronic devices that measure the ocean’s electrical conductivity—a metric closely linked to salinity—as well as temperature and depth, while the marine animals carrying them swim and dive.
Aaron Carlyle, the principal investigator and professor at the College of Earth, Ocean, and Environment, said, “Oceanographers have successfully used animal-borne sensors for years, particularly on elephant seals in polar regions where scientific observations are scarce.”
Carlyle noted that sharks offer a new opportunity for such research because they are abundant, widely distributed, and more accessible than many protected marine mammals.
To date, tagging sharks or attaching sensors to them has typically aimed at tracking their movements and the habitats they use.
University of Delaware researchers select sharks capable of collecting the most useful measurements for hurricane studies, preferring species that surface frequently enough for the devices to transmit data to satellites.
Previous analyses identified shortfin mako sharks, blue sharks, smooth hammerheads, and juvenile great white sharks as ideal candidates for such research in the North Atlantic.
Carlyle said, “We are particularly interested in the heat content of the upper ocean, known as the mixed layer.”
He added, “This is the part of the water column that significantly influences hurricane intensity. A warmer mixed layer means a stronger hurricane because it retains the heat that fuels storms.”
Caroline Vernitsky, a doctoral candidate in marine sciences at the University of Delaware, said the tagging process begins in early May, when highly migratory species approach the coast from their winter habitats in the Atlantic Ocean.
She explained that researchers travel 50 to 65 kilometers offshore on a research vessel, deploy baited lines, and wait—typically two to three hours—for sharks to take the bait.
Carlyle said, “The devices are attached to the dorsal fin. Each time the shark surfaces, the devices can connect and transmit data to the satellite network of ground receivers.”
He added that the tagging process is conducted under the supervision of an institutional animal care specialist to minimize impact on the sharks. The devices are secured using materials designed to degrade and fall off over time. Each shark also undergoes a health check before release, as stressed or injured sharks may not behave normally, which could affect data accuracy.
If the project succeeds, the data collected by the sharks could help improve hurricane intensity forecasts as storms approach the U.S. East Coast. Vernitsky noted that this information could provide communities from North Carolina to Massachusetts with more reliable data to bolster the resilience of coastal areas against increasingly powerful storms.
