14 DAY TRIAL // A collaborative scientific effort, featuring researchers from the United States and Australia, has recently made a very interesting discovery in the Southern Ocean. It would appear that winds in this area have the ability to trigger variations in the deepest layer of surface water responsible for regulating the way in which the sea and the atmosphere interact. With this new knowledge, experts could soon produce a much more complex and accurate map of how the two elements interact, and how these correlations influence the global weather patterns. Its effects on climate change and global warming could also be analyzed, the team believes.
The thing about the target of this new investigation – the surface-mixed layer of water – is the fact that it links together the deepest parts of the sea and the atmosphere above. This makes it terribly important for climate scientists. It plays a crucial part in a number of very relevant processes related to global weather, including the storage of carbon dioxide and heat from the atmosphere, as well as other chemical exchanges that take place between the air and the water. It also plays a very important part in the way waters in the ocean are stirred.
Surface water gets constantly pulled underneath, as new water from the depths climbs up. This is the basis for such things as the North Atlantic gyre, which is directly responsible for keeping Europe warm. Without it, the Old Continent would be covered in glaciers that would stretch all the way to the Mediterranean Sea, experts say. Changes in these natural processes would also influence the food chains in the oceans, with potentially catastrophic consequences for the environment. The new investigation was led by researchers at the Commonwealth Scientific and Industrial Research Organization (CSIRO), the main research agency in Australia.
According to CSIRO Wealth from Oceans Flagship oceanographer Dr Jean-Baptiste Sallee, the leader of the new investigation, the winds that blow over the Southern Ocean experienced a major shift over the past few decades. They are now stronger and blowing closer to Antarctica. “The shift in winds is one of the strongest trends in southern hemisphere climate over the last 30 years. The key question is; 'How does the wind change affect the ocean?' Our knowledge of how the Southern Ocean changes in time is poor because of the lack of ship-based observations in this remote region,” the expert says.
“But we now have seven years of year-round observations from a fleet of profiling floats known as Argo, which allow us to see for the first time how the Southern Ocean changes with the seasons and from year-to-year,” he adds. “We found that the depth of the mixed layer was more sensitive than we expected to a wind pattern known as the Southern Annular Mode, the major mode of variability of the southern hemisphere atmosphere. Even more surprising was the fact that the response is very different in different regions,” he concludes.