Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Satellite instrument helps tackle mysteries of ozone-eating clouds

11.04.2006


Polar stratospheric clouds have become the focus of many research projects in recent years due to the discovery of their role in ozone depletion, but essential aspects of these clouds remain a mystery. MIPAS, an instrument onboard ESA’s Envisat, is allowing scientists to gain information about these clouds necessary for modelling ozone loss.



"The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) is unique in its possibilities to detect polar stratospheric clouds (PSCs) since it is the first instrument with the ability to observe these clouds continuously over the polar regions especially during the polar night," Michael Höpfner of Germany’s Forschungszentrum Karlsruhe GmbH said.

Using data collected by MIPAS, a German-designed instrument that observes the atmosphere in middle infrared range, Höpfner and other scientists discovered a belt of nitric acid trihydrate (NAT) PSCs developing in the polar night over Antarctica in 2003 about one month after the first PSCs, which were composed of water crystals, were detected.


There are two classifications of PSCs – Type I clouds contain hydrated droplets of nitric acid and sulphuric acid, while Type II clouds consist of relatively pure water ice crystals.

The presence of NAT was detected because of MIPAS’ ability to map the atmospheric concentrations of more than 20 trace gases, including ozone as well as the pollutants that attack it.

"This has been the first evidence for the existence of NAT PSCs on a large scale," Höpfner said. NAT particles, which contain three molecules of water and one molecule of nitric acid, enhance the potential for ozone destruction in polar regions.

The thinning of the ozone is caused by the presence of man-made pollutants in the atmosphere such as chlorine, originating from man-made pollutants like chlorofluorocarbons (CFCs). During the southern hemisphere winter, temperatures drop to very low levels causing the chemicals in the stratosphere, which is in complete darkness during the winter, to freeze and form PSCs that contain chlorine.

Now banned under the Montreal Protocol, CFCs were once widely used in aerosol cans and refrigerators – and have not vanished from the air. CFCs themselves are inert, but ultraviolet radiation high in the atmosphere breaks them down into their constituent parts, which can be highly reactive with ozone.

As the polar spring arrives, sunlight returns and creates chemical reactions in PSCs responsible for converting benign forms of chlorine into highly ozone-reactive radicals that spur ozone depletion. A single molecule of chlorine has the potential to break down thousands of molecules of ozone.

NAT PSCs enhance the potential for chlorine activation and can also sediment and irreversibly remove nitrogen from the lower stratosphere, causing a process known as denitrification, which slows the return of chlorine to its inactive form and allows for ozone destruction to continue.

Höpfner and fellow scientists were able to explain the sudden NAT formation of PSCs in 2003 by temperature disturbances in waves over the Antarctic Peninsula and the Ellsworth Mountains, suggesting a more significant role for mountain waves in the formation of Antarctic’s PSCs than previously thought.

According to Höpfner, the presence of PSCs could intensify in the future due to a globally changing climate where the Earth’s surface gets warmer due to trapped greenhouse gases but the stratosphere gets colder, providing an environment in which the clouds can form. An increase in PSCs could counteract the recovery of the ozone layer.

Although scientific efforts have focused on determining PSC composition and their formation mechanisms, the process causing the ozone depletion is far from understood. In order to gain a better understanding of ozone depletion, scientists must continue obtaining data which allows them to measure the key species involved in the process.

Mariangela D’Acunto | alfa
Further information:
http://www.esa.int/esaEO/SEMBZNNFGLE_planet_0.html

More articles from Ecology, The Environment and Conservation:

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Transport of molecular motors into cilia

28.03.2017 | Life Sciences

A novel hybrid UAV that may change the way people operate drones

28.03.2017 | Information Technology

NASA spacecraft investigate clues in radiation belts

28.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>