he Ocean Most absorbed heat and the carbon emitted by human activity, but the amount that can be absorbed depends on turbulence within said body of water, both being pushed toward the depths or drawn toward the surface. That’s why an international group of scientists has warned that these waves and other forms of underwater turbulence will not be accurately reflected in climate models and warned that this could happen. Changes in their role in storage.
As they explained, trade Atlantic Ocean It plays a major role in regulating global heat and carbon balance through the inter-hemispheric transport of water masses. And while most of this occurs along near-horizontal surfaces of high density in the ocean interior, vertical movement across density levels is key to bringing deep waters back to the surface. This multi-density transport is mainly facilitated by internal waves breaking turbulence and in processes close to the boundary.
It is for the team of specialists led by the University of Cambridge, Oxford and California San Diego that the underwater waves In the depths of the ocean surface, some of them up to 500 meters high, it plays an important role in How is heat and carbon stored? there. They even quantified the impact of these waves and other forms of underwater turbulence in the Atlantic Ocean and found that their importance was not accurately captured in the climate models that guide government policy.
While the ocean absorbs most of the heat and carbon emitted by human activity, The amount that can be stored depends on turbulence within the periphery. It is that although these submarine waves are already known, their significance in heat and carbon transfer has not been fully understood. The results of this research are published in the journal AGU predecessorIntra-ocean turbulence has been shown to be more important for the transfer of carbon and heat on a global scale than previously imagined.
Ocean circulation transports warm water from the tropics to the North Atlantic, where it cools, sinks, and returns south to the ocean depths like a giant conveyor belt. The Atlantic offshoot of this circulation pattern, called the Atlantic meridional overturning circulation (AMOC), plays a key role in regulating global heat and carbon balance, as ocean circulation redistributes heat to the polar regions, where ice melts, and carbon to the ocean depths where It can be stored for thousands of years.
“If you were to take a picture of the inside of the ocean, you would see a lot of complex dynamics in action,” explained first author Laura Simoli, from Cambridge’s Department of Applied Mathematics and Theoretical Physics. Beneath the surface of the water are jets, currents, and waves. In the depths of the ocean, these waves can be up to 500 meters high, but they break like a wave on the shore.
For his part, Ali Mashayek, from the Department of Earth Sciences at Cambridge, continued: “The Atlantic Ocean is distinctive in the way it affects the global climate. It has a strong pole-to-pole circulation from the upper reaches to the depths. Also, water moves faster on the surface than at depth. “.
Over the past few decades, researchers have been studying whether AMOC might be a factor that explains why the Arctic is losing so much ice cover, while some of the Antarctic ice sheets are growing. One possible definition of this phenomenon is that the heat absorbed by the ocean in the North Atlantic takes several hundred years to reach Antarctica.
Now, using a combination of remote sensing, shipboard measurements, and data from autonomous buoys, Researchers have discovered that heat from the North Atlantic can reach Antarctica much faster than previously thought. Like a big cake, the ocean is made up of different layers, with cooler, denser water at the bottom and warmer, lighter water at the top.
Most heat and carbon transfer in the ocean occurs within a given layer, but heat and carbon can also be transferred between denser layers, causing deeper waters to return to the surface. The researchers found that the movement of heat and carbon between layers is facilitated by small-scale turbulence, a phenomenon that is not fully represented in climate models.
Mixing estimates from different observation platforms showed evidence of small-scale perturbation in the upper branch of the circulation, consistent with theoretical predictions for inland ocean waves. Various estimates have shown that the disturbance mainly affects the density layers associated with the deep water core moving south from the North Atlantic Ocean into the Southern Ocean. This means that The heat and carbon carried by these water masses have a high probability of moving through different density levels.
“Climate models account for disturbances, but mainly how they affect ocean circulation,” said Simoli. But we found that turbulence is dynamic in itself and plays a major role in how much carbon and heat the ocean absorbs and where it is stored. Many climate models have a very simplistic representation of the role of perturbation on a small scale, but we have shown that it is important and should be treated more carefully.”
“For example, its role in ocean circulation exerts control over the amount of human heat that reaches the Antarctic ice sheet and the timing at which it does so.” Research indicates that a The urgent need to ‘fit sensors into global monitoring matrices and more accurately represent disturbances small scale in climate models, to allow scientists to make more accurate predictions of future impacts of climate change.”
This research was contributed by Helen Johnson, David B. Marshall, Alberto C. Navera Garabato, Caitlin B. Whalen, Clement Vick, Casemiro de LaVergne, Matthew H. Alford, Jennifer A. MacKinnon, and Lynn D.