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.
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
25.04.2018 | Physics and Astronomy
25.04.2018 | Physics and Astronomy
25.04.2018 | Information Technology