The study is published in the journal Nature Geoscience. The scientists used a computer model developed at the Danish Centre for Earth System Science (DCESS) that analyses global changes extending 100,000 years into the future.
The DCESS model includes atmosphere, ocean, ocean-sediment, land-biosphere and lithosphere modules. According to the study, it reproduces 'observed evolutions since 1765 of key climate metrics including atmosphere and ocean warming, atmospheric gas contents and ocean and land-biosphere CO2 uptakes'.
Two emissions scenarios of the Intergovernmental Panel on Climate Change (IPCC) were evaluated: one with a moderate (3°C) temperature increase and one with a high (4.8°C) temperature rise. In both simulations, there was oxygen loss in the upper 500m of the ocean, largely in response to surface-layer warming. Importantly, overturning circulation in the deep ocean, which pulls oxygenated surface waters down to the depths of the ocean, decreased. The high-emissions scenario in particular predicted 'severe, long-term ocean oxygen depletion,' and it was clear that the suboxic regions of the ocean, which are void of fish and other larger creatures, would expand in both cases.
Observations in the oceans already show that suboxic areas are expanding as the atmosphere and ocean warm. In line with this and other supporting observations, the model projects a three- to seven-fold expansion in suboxic zones. The authors explain that as suboxic zones expand, different microbes and plankton take over. This forces a shift towards nitrogen fixers, which the researchers say would probably force large, unpredictable changes in ocean ecosystem structure and productivity, with serious consequences.
The study's conclusions are simple: 'Reduced fossil-fuel emissions would be needed to limit ongoing oxygen depletion and its long-term adverse effects.'
Extreme oceanic oxygen depletion events are thought to be behind some of the large extinction events in the Earth's history, including the largest such event 250 million years ago.
Upcycling of PET Bottles: New Ideas for Resource Cycles in Germany
25.06.2018 | Fraunhofer-Institut für Betriebsfestigkeit und Systemzuverlässigkeit LBF
Dry landscapes can increase disease transmission
20.06.2018 | Forschungsverbund Berlin e.V.
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
16.07.2018 | Physics and Astronomy
16.07.2018 | Life Sciences
16.07.2018 | Earth Sciences