Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Plankton may influence climate change says UCSB scientist

06.05.2004


Plankton appear to play a major role in regulating the global climate system, according to new research



David Siegel, professor of geography at the University of California, Santa Barbara, and director of the Institute for Computational Earth System Science, made the discovery with his former Ph.D. student Dierdre Toole, who is now based at Woods Hole Oceanographic Institute.

In an article in the May 6 issue of the journal Geophysical Research Letters, the scientists explain their research in the Sargasso Sea, approximately 50 miles southeast of the island of Bermuda. Siegel’s research group has been making observations at this location since 1992.


Phytoplankton are tiny, single-celled floating plants. They inhabit the upper layers of any natural body of water where there is enough light to support photosynthetic growth. They are the base of the ocean’s food web, and their production helps to regulate the global carbon cycle. They also contribute to the global cycling of many other compounds with climate implications.

One of these compounds is a volatile organic sulfur gas called dimethyl sulfide or DMS. Scientists had previously theorized that DMS is part of a climate feedback mechanism, but until now there had been no observational evidence illustrating how reduced sunlight actually leads to the decreased ocean production of DMS. This is the breakthrough in Toole and Siegel’s research.

They describe how the cycle begins when the ocean gives off DMS to the lower atmosphere. In the air, DMS breaks down into a variety of sulfur compounds that act as cloud-condensing nuclei, leading to increased cloudiness. With more clouds, less sunlight reaches the Earth and the biological processes which produce DMS are reduced.

According to their research, it appears that phytoplankton produce organic sulfur compounds as a chemical defense from the damaging effects of ultraviolet radiation and other environmental stresses, in much the same way as our bodies use vitamins E and C to flush out molecules that cause cellular damage.

Siegel and Toole found that ultraviolet radiation explained almost 90 percent of the variability in the biological production of DMS. They showed that summertime DMS production is "enormous," and that the entire upper layer of DMS content is replaced in just a few days. This demonstrates a tight link between DMS and solar fluxes.

"The significance of this work is that it provides, for the first time, observational evidence showing that the DMS-anti-oxidant mechanism closes the DMS-climate feedback loop," said Siegel. "The implications are huge. Now we know that phytoplankton respond dramatically to UV radiation stresses, and that this response is incredibly rapid, literally just days."

He explained that the findings give new impetus for scientists to re-examine the DMS-climate feedback hypothesis. And the DMS-climate feedback may also play out under possible global warming and climate change scenarios.

As the Earth’s ozone shield thins and greenhouse gases increase, higher ultraviolet radiation will reach the surface layer of the oceans. The findings indicate that phytoplankton will then produce more DMS in response to this increased ultraviolet radiation, causing increasing cloudiness and mitigating the effects of global warming. However, Siegel is careful to note that while the process may mitigate global warming it will not reverse the trend.

The project was funded by NASA. NASA’s Earth Science Enterprise is dedicated to understanding the Earth as an integrated system and applying Earth System Science to improve prediction of climate, weather, and natural hazards using the unique vantage point of space.


Note: David Siegel can be reached at 805-893-4547 or by e-mail at davey@icess.ucsb.edu.

Gail Gallessich | EurekAlert!
Further information:
http://www.ucsb.edu/

More articles from Earth Sciences:

nachricht Large-Mouthed Fish Was Top Predator After Mass Extinction
26.07.2017 | Universität Zürich

nachricht Strength of tectonic plates may explain shape of the Tibetan Plateau, study finds
25.07.2017 | University of Illinois at Urbana-Champaign

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Abrupt motion sharpens x-ray pulses

Spectrally narrow x-ray pulses may be “sharpened” by purely mechanical means. This sounds surprisingly, but a team of theoretical and experimental physicists developed and realized such a method. It is based on fast motions, precisely synchronized with the pulses, of a target interacting with the x-ray light. Thereby, photons are redistributed within the x-ray pulse to the desired spectral region.

A team of theoretical physicists from the MPI for Nuclear Physics (MPIK) in Heidelberg has developed a novel method to intensify the spectrally broad x-ray...

Im Focus: Physicists Design Ultrafocused Pulses

Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.

Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

New 3-D imaging reveals how human cell nucleus organizes DNA and chromatin of its genome

28.07.2017 | Health and Medicine

Heavy metals in water meet their match

28.07.2017 | Power and Electrical Engineering

Oestrogen regulates pathological changes of bones via bone lining cells

28.07.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>