Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How the detergent of the atmosphere is regenerated

07.10.2013
Juelich troposphere researchers demonstrate effective recycling of radicals during isoprene degradation

Hydroxyl (OH) radicals – known as the detergent of the atmosphere – decompose isoprene in the air. This leads to the creation of new OH radicals, which are then able to purify the air of other pollutants and trace gases. The scientific community had previously only been able to speculate about this mechanism.


The large atmosphere simulation chamber SAPHIR provides a platform for reproducible studies of well-defined atmospheric-chemical mechanisms.

Credit: Forschungszentrum Jülich

The atmosphere has an astonishing ability to cleanse itself. Chemical processes ensure that trace gases and pollutants are removed from the atmosphere – such as isoprene, which is largely produced by forests. Without these processes global warming would be even more severe and , air quality much poorer. Just a few years ago, scientists thought that the degradation of isoprene considerably reduced the concentration of OH radicals.

During studies in China, troposphere researchers from Jülich's Institute of Energy and Climate Research simultaneously determined high concentrations of both OH radicals and trace gases such as isoprene. Other research groups made similar observations in the air above North American forests and tropical rainforests. The obvious conclusion was that during isoprene degradation something happens to regenerate the OH radicals.

"In the past few years, there has been an intensive discussion in the scientific community about what this mechanism could be. But without actual proof this remained pure speculation. Now we have succeeded in demonstrating this process," says the Jülich troposphere researcher, Dr. Hendrik Fuchs.

The scientists recreated the natural conditions prevailing in the atmosphere above China and the tropical rainforests in the Jülich simulation chamber, SAPHIR. This chamber enables researchers to simulate the degradation of even slight quantities of trace gases. It is equipped with exactly the same measuring instruments as are used in field experiments. "It is only this particular combination that makes it possible to study the processes precisely. SAPHIR means that we enjoy unique conditions here at Jülich," says head of institute Prof. Andreas Wahner. Jülich scientists were indeed able to confirm the basic principles of this mechanism and to quantify its impact on OH regeneration. The process takes place much faster than thought before, but not so effectively as some researchers had assumed.

Since the degradation process is now understood for isoprene, scientists can begin to quantitatively investigate feedback effects. Relations between self-cleansing processes in the atmosphere and the climate are particularly interesting for the Jülich researchers. More OH radicals in the air mean that more greenhouse gases such as methane can be degraded. Furthermore, in contrast to all other known mechanisms for the degradation of isoprene, less climate-damaging ozone is produced in the atmosphere than previously assumed. Moreover, the effectiveness of the process increases with air temperature. "We may possibly have identified an important interaction between air quality and climate change leading to the accelerated degradation of trace gases in an atmosphere that is heating up," adds the deputy head of institute Dr. Andreas Hofzumahaus.

The Jülich investigations are part of the ongoing EU project PEGASOS (Pan-European Gas-AeroSOls-climate interaction Study) concerned with interactions between atmospheric chemistry, air quality and climate.

Original publication:

Experimental evidence for efficient hydroxyl radical regeneration in isoprene oxidation.
H. Fuchs et al.
Nature Geoscience, published online 6 October 2013, DOI: 10.1038/ngeo1964
Further information:
Institute of Energy and Climate Research – Troposphere (IEK-8)
http://www.fz-juelich.de/iek/iek-8/EN/Home/home_node.html
SAPHIR atmospheric simulation chamber
http://www.fz-juelich.de/iek/iek-8/EN/Expertise/Infrastructure/SAPHIR/SAPHIR_node.html
EU PEGASOS project
http://www.fz-juelich.de/iek/iek-8/EN/AboutUs/Projects/PEGASOS/PEGASOS_node.html
Contact:
Dr. Hendrik Fuchs
Institute of Energy and Climate Research – Troposphere (IEK-8)
Forschungszentrum Jülich
Tel: +49 2461 61-6741
h.fuchs@fz-juelich.de
Press contact:
Annette Stettien, Forschungszentrum Jülich
Tel: +49 2461 61-2388
a.stettien@fz-juelich.de

Dr. Hendrik Fuchs | EurekAlert!
Further information:
http://www.fz-juelich.de

More articles from Earth Sciences:

nachricht Climate satellite: Tracking methane with robust laser technology
22.06.2017 | Fraunhofer-Gesellschaft

nachricht How reliable are shells as climate archives?
21.06.2017 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>