Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists determine biological and ecosystem changes in polar regions linked to solar variability

29.09.2003


A Lawrence Livermore National Laboratory scientist, in collaboration with an international team of colleagues, has reported that noticeable changes in the sub-polar climate and ecosystems appear to be linked to variations in the sun’s intensity during the past 12,000 years.



The research, titled "Cyclic Variation and Solar Forcing of Holocene Climate in the Alaskan Subarctic," is reported in today’s (Sept. 26) issue of Science.

Using core sediment samples from Arolik Lake in the tundra region along the southwestern coast of Alaska, Thomas Brown of Livermore’s Center for Accelerator Mass Spectrometry measured the amount of carbon-14 in samples to provide a chronological framework for the biological and organic evidence of climate and ecosystem changes, which occurred during the Holocene Epoch (12,000 years ago to present).


By studying biological, geochemical and isotopic constituents of sediment samples (such as biogenic silica from single-celled algae, which reflects lake productivity), the researchers determined that variations of these components provided evidence of climate and ecosystem variations over the past 12,000 years.

The scientists identified significant cycles lasting 200, 435, 590 and 950 years in the 12,000-year record, which are consistent with previously recognized cycles of solar activity. By comparison of the Alaskan subarctic record to recent findings of North Atlantic ice cover variations and solar-activity-modulated production records of beryllium- 10 and carbon-14, the scientists showed that the changes in sub-polar climate and ecosystems are correlated with records related to slight variations in solar irradiance.

The data from biogenic silica, North Atlantic sea ice, and beryllium-10 and carbon-14 showed "remarkable correlation during the cycles", Brown said.

"We found natural cycles involving climate and ecosystems that seem to be related to weak solar cycles, which, if verified, could be an important factor to help us understand potential future changes of Earth’s climate," said principal investigator Feng Sheng Hu of the University of Illinois at Champaign- Urbana.

"Will changes in solar irradiation in the future mitigate or exacerbate global warming in the future? They may do both. A period of high solar irradiance on top of high levels of greenhouse gases could result in unprecedented warming."

Other contributors come from Northern Arizona University, the Weizmann Institute of Science in Israel, Brown University and Columbia University.


###
Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy’s National Nuclear Security Administration.

Anne Stark | EurekAlert!
Further information:
http://www.berkeley.edu/

More articles from Earth Sciences:

nachricht New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland
19.01.2017 | University of Gothenburg

nachricht Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>