Massive freshwater overflow accumulates in the Arctic

The enormous amount of fresh water that accumulates in the Arctic Ocean due to global warming, it can flow en masse to the Labrador Sea altering local and global ocean currents.

Beaufort sea, which is the largest freshwater reservoir in the Arctic Ocean, has increased its content of40% sweet gua over the past two decades. How and where this water will flow into the Atlantic Ocean is important to local and global ocean conditions.

A study by the University of Washington, Los Alamos National Laboratory and National Oceanic and Atmospheric Administration (NOAA) shows that this freshwater crosses the Canadian archipelago to reach the Labrador Sea on the Canadian east coast, rather than through the wider shipping lanes that connect to the seas of northern Europe. The study was published in Nature communications.

“The Canadian archipelago is an important channel between the Arctic and the North Atlantic”, the main author said in a statement Jiaxu Zhang, postdoctoral researcher at the University of Washington at the Cooperative Institute for Climate, Ocean and Ecosystem Studies. “In the future, if the winds weaken and fresh water is released, it is possible that this large amount of water has a great influence on the Labrador Sea region. “

This finding has implications for the marine environment of the Labrador Sea, as arctic water tends to be cooler but also rich in nutrients. This pathway also affects larger ocean currents, i.e. conveyor belt circulation in the Atlantic Ocean in which cooler, heavier water sinks into the North Atlantic and returns to the surface as Gulf. Stream. The softer, lighter water entering the Labrador Sea could slow this reversal in circulation.

“We know that the Arctic Ocean is showing one of the biggest signs of climate change,” said co-author Wei Cheng of the University of Washington Cooperative Institute for Climate Studies, Ocean and the atmosphere. “Right now this fresh water is still trapped in the Arctic. But once released it can have a very big impact “added.

The softest water reaches the Arctic Ocean through rain, snow, rivers, the relatively milder coves of the Pacific Ocean, as well as the recent melting of sea ice from the Arctic Ocean. The softest, lightest water floats up, and the clockwise winds in the Beaufort Sea push this water lighter to create a dome.

When these winds ease, the dome will flatten and fresh water will be released into the North Atlantic.

“People have already spent a lot of time studying why the fresh water in the Beaufort Sea has increased so much in recent decades”said Zhang, who started work at the Los Alamos National Laboratory. “But they rarely care where the fresh water goes and we think it’s a much bigger problem,” he said.

Using a technique Zhang developed to track ocean salinity, researchers simulated ocean circulation and tracked the spread of fresh water from the Beaufort Sea during a past event that occurred between 1983 and 1995 .

His experience showed that most of the fresh water reached the Labrador Sea. across the Canadian archipelago, a complex set of narrow passages between Canada and Greenland. This region is poorly studied and has been considered less important for freshwater flow than the much wider Fram Strait, which connects to the seas of northern Europe.

In the model, the freshwater discharge from 1983 to 1995 traveled primarily along the North American Highway and significantly reduced salinities in the Labrador Sea, a 0.2 part per mile refresh on its western edge. shallower, off Newfoundland and Labrador, and 0.4 part per thousand in the Labrador Current.

The volume of fresh water currently in the Beaufort Sea is approximately double the size of the case study, more … than 23,300 cubic kilometers or more than 5,500 cubic miles. This volume of fresh water released into the North Atlantic could have significant effects. The exact impact is unknown. The study focused on past events and current research is examining where the current freshwater buildup might end up and what changes it might trigger.

“A freshwater discharge of this magnitude in the North Atlantic subpolar could affect a critical circulation pattern, called the South Atlantic reverse circulation, which has a significant influence on the climate of the northern hemisphere ”said co-author Wilbert Weijer from the Los Alamos National Laboratory.

Europa Press