AWI researchers measure temperatures of minus 90 degrees Celsius and lower at 20 kilometres altitude
Unusual weather development in the Arctic leads to ozone depletion. According to the researchers of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) in the past weeks an extreme cold spell in the Arctic stratosphere has created conditions that might cause severe ozone depletion over the Arctic in March – if the next few weeks will not bring a significant warming.
"At about 20 kilometres altitude over the Arctic, the air has been as cold as minus 90 degrees Celsius for weeks," explains AWI atmospheric researcher Dr Marion Maturilli. "Since the beginning of December, above our Arctic research station on Spitsbergen the mean temperature in the stratosphere has been eight degrees Celsius below the long-term average and two degrees Celsius below the previous minimum. These are conditions that can result in substantial ozone depletion."
The depletion of the ozone layer is caused by chlorofluorocarbons, which humankind has released in large quantities over the past decades. Their breakdown products attack the ozone layer, especially after prolonged periods of extreme cold.
Such cold spells usually only occur in the Antarctic winter, which is why an ozone hole forms over the Antarctic every year in spring.
"In the Arctic, on the other hand, the temperatures in the stratosphere are usually higher and much more variable, which means that ozone depletion is limited. Here, severe ozone losses only occur following periods of particularly low temperatures, which we have experienced only very rarely – for example after the cold stratospheric winter of 2010/2011. At that time, ozone depletion also led to a pronounced minimum over the northern hemisphere," says AWI researcher Dr Markus Rex, the coordinator of the EU funded project StratoClim, which observes the situation in the Arctic closely.
Conditions created by stable low-pressure vortex
Model calculations performed by AWI researchers based on the extreme cold spell in recent weeks show that the chemical conditions in the Arctic stratosphere already now exceed the ozone depletion potential of the 2010/2011 winter. "The air masses with these unusual conditions are currently caught in a low-pressure vortex high over the Arctic. Transport of ozone into the vortex has also been low and an ozone minimum has already started to develop. By mid-February more than a quarter of the total ozone above the Arctic will have been destroyed chemically. At that time ozone depletion within the vortex will gain momentum when more intense solar light returns to the Arctic at the end of the polar night," according to Markus Rex. "Should the vortex persist until well into March, the formation of a deep ozone minimum over the Arctic has to be expected. However, if the vortex breaks up before then, the air masses will sufficiently mix with fresh air from lower latitudes and the Arctic will narrowly avoid a new record of ozone depletion," the researcher explains.
The scientists are not currently able to reliably predict the fate of the vortex beyond late February and whether it will break up in time. If a pronounced ozone minimum does develop, there is a chance, that it will drift over Central Europe. In order to closely follow the ozone loss over the Arctic, the StratoClim consortium, together with further international collaborators, is sending hundreds of ozone sensors into the stratosphere from a network of 30 observation stations in an on-going coordinated effort. Furthermore, measurement flights into the Arctic stratosphere with a high-altitude research aircraft are planned for early April.
Cooling of the stratosphere is a consequence of global climate change
"We are expecting a general cooling of the stratosphere as a result of global climate change. The mechanisms that regulate the temperatures of the Arctic stratosphere, however, are complicated and not fully understood. Whether the record low temperatures in the past weeks are linked to climate change is therefore the subject of active research," says Markus Rex.
The production of ozone-depleting CFCs is now banned worldwide by the Montreal Protocol. In the long term, the ozone layer is therefore expected to make a full recovery by the end of the century. "The current unusual situation in the Arctic does not change this positive outlook, even if a record ozone loss over the Arctic should occur this spring," says Markus Rex.
These impressive results probably make the Montreal Protocol the most successful international treaty for the protection of the global environment. However: "Unfortunately, the CFCs already released cannot be removed from the atmosphere and their natural breakdown in the atmosphere is very slow. During the next one to two decades, following unusual cold spells, the Arctic stratosphere will therefore remain susceptible to severe ozone losses," the AWI expert explains.
Related Science article: Record ozone hole may open over Arctic in the spring - DOI:10.1126/science.aaf4033
Notes for Editors:
You can find printable photos of rising ozone sensors at the German-French Arctic research station AWIPEV in Ny-Ålesund, Spitsbergen, in the online version of this press release at: http://www.awi.de/nc/en/about-us/service/press.html
Your scientific contacts at the Alfred Wegener Institute in Potsdam are:
• Topic ozone: Dr Markus Rex (tel.: +49-(0)331 288–2127; e-mail: Markus.Rex(at)awi.de)
• Topic meteorological measurements on Spitsbergen: Dr Marion Maturilli (tel.: +49 (0)331 288–2109; e-mail: Marion.Maturilli(at)awi.de)
Please contact Sina Löschke at the AWI press office (tel.: +49(0)471 4831–2008; e-mail: medien(at)awi.de) if you have further questions.
The Alfred Wegener Institute researches in the Arctic, the Antarctic and oceans in the central and high latitudes. It coordinates polar research in Germany and provides important infrastructure such as the research icebreaker Polarstern and stations in the Arctic and Antarctic for the international science community. The Alfred Wegener Institute is one of the 18 research centres belonging to the Helmholtz Association, which is Germany's largest scientific organisation.
StratoClim (Stratospheric and upper tropospheric processes for better Climate predictions) is a five-year research project funded by the EU, studying changes in the chemical composition of the upper troposphere and stratosphere. The consortium of 28 European research institutions is co-ordinated by AWI. Results of the project will directly improve the representation of key atmospheric processes in global climate models and enhance thus the overall understanding of climate change and its environmental and socio-economic implications. For more information on StratoClim please visit: http://www.stratoclim.org/
Ralf Röchert | idw - Informationsdienst Wissenschaft
Stagnation in the South Pacific Explains Natural CO2 Fluctuations
23.02.2018 | Carl von Ossietzky-Universität Oldenburg
First evidence of surprising ocean warming around Galápagos corals
22.02.2018 | University of Arizona
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy