The researchers analysed the data and spotted an unnoticed temperature-salinity curve
A previously hidden water mass has been identified in the middle of the Atlantic, offering a new perspective on ocean dynamics. The newly discovered Atlantic Equatorial Water forms along the equator as ocean currents merge distinct water bodies from the north and south, Live Science reported.
The researchers published their findings in the journal Geophysical Research Letters. The researchers spotted waters mixing along the equator in the Pacific and Indian oceans.
"It seemed controversial that the equatorial water mass is present in the Pacific and Indian oceans but missing in the Atlantic Ocean because the equatorial circulation and mixing in all three oceans have common features," Viktor Zhurbas, a physicist and oceanologist at The Shirshov Institute of Oceanology in Moscow, told Live Science. "The identified new water mass has allowed us to complete (or at least more accurately describe) the phenomenological pattern of basic water masses of the World Ocean."
The ocean's vast expanse is not a uniform body of water, but rather a dynamic tapestry of interconnected masses and layers, constantly intermingling and separating under the influence of currents, eddies, and fluctuations in temperature and salinity.
These distinct components, known as water masses, bear the imprint of their origins and share unique physical properties, such as density and the distribution of oxygen, nitrate, and phosphate isotopes.
To discern these water masses, oceanographers map the interplay between temperature and salinity across the ocean – two crucial parameters that govern the density of seawater.
To find the missing water mass, the scientist combed through data collected by the Argo program, an international array of robotics, self-submerging floats scattered across the world's oceans.
The researchers analysed the data and spotted an unnoticed temperature-salinity curve parallel to the curves marking out the North Atlantic and South Atlantic Central waters to the north and south: the Atlantic Equatorial Water, the media outlet reported.
"It was easy to confuse the Atlantic Equatorial Water with the South Atlantic Central Water, and in order to distinguish them it was necessary to have a fairly dense network of vertical temperature and salinity profiles covering the entire Atlantic Ocean," Zhurbas said.