Man-made climate change has increased surface temperatures throughout the planet, leading to increased atmospheric instability and extreme weather events, such as hurricanes.
But in the oceans, higher temperatures have a different effect, slowing the mixing between the warming surface and cooler, oxygen-rich water, the researchers said.
This ocean “stratification” means that less deep water is moving towards the surface carrying oxygen and nutrients, while water at the surface absorbs less atmospheric carbon dioxide.
In a report published in the journal Nature climate changeThe international team of climate scientists said they found that globally stratification increased by “substantial” 5.3 percent from 1960 to 2018.
Much of this stabilization occurred toward the surface, and was largely attributed to the increase in temperature.
He said the process is also faster than the melting of sea ice, meaning that more fresh water – which is lighter than saltwater – also accumulates on the ocean surface.
Study author Michael Mann, a climate science professor at Pennsylvania State University, said in a comment published in Newsweek that “seemingly technical discovery has profound and disturbing implications.”
These include potentially more “intense, catastrophic storms” when the ocean surface heats up.
Mann also pointed to a decrease in the amount of CO2 absorbed, which could mean that carbon pollution in the atmosphere increases rapidly.
He cautioned that sophisticated climate models often reduce ocean stratification and its effects may be underestimated.
With warmer upper waters receiving less oxygen, there are implications for marine life.
According to the Intergovernmental Panel for Climate Change (IPCC), the oceans’ population is kept alive by absorbing a quarter of man-made CO2 and soaking more than 90 percent of the heat generated by greenhouse gases – but at a terrible cost.
Ceases have become acidic, possibly reducing their ability to draw CO2. Warm surface waters have expanded the force and range of deadly tropical storms.
Marine heatwaves are eroding coral reefs, and melting glaciers and ice sheets, accelerating sea level rise.
Research published last year US Proceedings of the National Academy of Sciences It was calculated that climate change would empty the sea by about a fifth of all living beings measured by mass by the end of the century.
© Agnes France-Presse