Published 18:01 IST, December 10th 2019
NASA understands ocean currents around Antarctica with help of elephant seal
NASA conducted a study on the movement of ocean currents and the exchange of heat with the help of elephant seal. Oceanographers deploy sensors on head of seal
In the latest study published by NASA’s Jet Propulsion Laboratory, an oceanographer studied the movement of ocean currents around the Antarctic for three months. The study was conducted with the help of a southern elephant seal, who was deployed with a small hat-like instrument which was equipped with sensors.
Movement of ocean currents
The study looked at the movement of Antarctic Circumpolar Current which influences the movement of warm water, which in turn has a major role in climate change. The study found that the “Antarctic Circumpolar Current flows in a loop around Antarctica, connecting the Atlantic, Pacific, and Indian oceans”. Scientists call this as the most important ocean currents in our climate system as it helps in the exchange of heat and other important properties among various oceans which it connects. The scientists were unable to figure out the process of the exchange of heat which is directed vertically from top to bottom. The report said that “This current is very turbulent, producing eddies - swirling vortices of water similar to storms in the atmosphere - between 30 to 125 miles (50 to 200 kilometres) in diameter. It also spans some 13,000 miles (21,000 kilometres) through an especially remote and inhospitable part of the world, making it one of the most difficult currents for scientists”.
The sensors used by the Scientists were able to record results every time the seal would dive. It recorded the time, depth and water temperature. Throughout the study, the seal travelled 3,000 miles across the Antarctic. “The seal made around 80 dives at depths ranging from 550 to 1,090 yards (500 to 1,000 meters) per day during this time.” The data collected by the seal was combined with altimetry data from satellites, which collect data related to ocean currents, wind direction, and wave height. This will provide new insight into the research.
According to a study published in Nature Geoscience, oceanographer Siegelman that the ocean current consists of swirling eddies. Siegelman said, "These medium-sized eddies are known to drive the production of small-scale fronts - sudden changes in water density similar to cold and warm fronts in the atmosphere.” She further added, “We found that these fronts were evident some 500 meters [550 yards] into the ocean interior, not just in the surface layer like many studies suggest and that they played an active role in vertical heat transport." According to the new results provided by the seal, it is difficult to conclude that the movement of heat is from the surface to the interior of the ocean.
Updated 18:26 IST, December 10th 2019