The origin of the strong ozone losses are very low temperatures in the stratosphere (about 20 km altitude) that release chlorine and bromine atoms from the chlorofluorocarbons (cfc) and related brominated substances emitted by humans and catalytically destroy ozone. The measurements by SCIAMACHY confirm high chlorine activation in March 2011.
Stratospheric temperatures in the Arctic are very variable from winter to winter. Last year temperatures and ozone above the Arctic were very high. The year-to-year variability is related to the global upper atmosphere circulation. In winters with a strong circulation more ozone is transported into high latitudes and polar stratospheric temperatures are getting higher resulting in less polar ozone depletion.
In the science community there is currently a debate on why just this Arctic winter was very cold. In a changing climate, it is expected that on average stratospheric temperatures cool which means more chemical ozone depletion will occur. On the other hand many studies show that the stratospheric circulation in the northern hemisphere may be enhanced in the future and consequently more ozone will be transported from the tropics into high latitudes and reduce ozone depletion. The measures by the Montreal protocol banning cfc’s and related species have succeeded in that the stratospheric halogen (chlorine and bromine) load is now slowly declining. Nevertheless strong chemical ozone depletion will still occur during unusually cold Arctic winters in coming decades.
The Institute of Environmental Physics of the University of Bremen (IUP) is routinely processing satellite data from GOME (since 1995), SCIAMACHY (since 2002), and GOME-2 (since 2007). IUP has initiated the GOME and SCIAMACHY projects. Spectral data from the satellite instruments are provided by ESA (GOME/ERS-2, SCIAMACHY/Envisat) and EUMETSAT (GOME-2/Metop-A). Calculations using a chemistry-transport model at IUP have shown that about half of the Arctic ozone has been chemically depleted during this winter.Contact:
Eberhard Scholz | idw
In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
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