Featured Research

from universities, journals, and other organizations

Scientists Determine Biological And Ecosystem Changes In Polar Regions Linked To Solar Variability

Date:
September 29, 2003
Source:
University Of California - Berkeley
Summary:
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.

LIVERMORE, Calif. – 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.


Story Source:

The above story is based on materials provided by University Of California - Berkeley. Note: Materials may be edited for content and length.


Cite This Page:

University Of California - Berkeley. "Scientists Determine Biological And Ecosystem Changes In Polar Regions Linked To Solar Variability." ScienceDaily. ScienceDaily, 29 September 2003. <www.sciencedaily.com/releases/2003/09/030929054445.htm>.
University Of California - Berkeley. (2003, September 29). Scientists Determine Biological And Ecosystem Changes In Polar Regions Linked To Solar Variability. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2003/09/030929054445.htm
University Of California - Berkeley. "Scientists Determine Biological And Ecosystem Changes In Polar Regions Linked To Solar Variability." ScienceDaily. www.sciencedaily.com/releases/2003/09/030929054445.htm (accessed October 20, 2014).

Share This



More Earth & Climate News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Powerful Hurricane Gonzalo Heads to Bermuda

Raw: Powerful Hurricane Gonzalo Heads to Bermuda

AP (Oct. 17, 2014) Hurricane Gonzalo pounded Bermuda with wind and heavy surf on Friday, bearing down on the tiny British territory as a powerful Category 3 storm that could raise coastal seas as much as 10 feet. (Oct. 17) Video provided by AP
Powered by NewsLook.com
So, Kangaroos Didn't Always Hop

So, Kangaroos Didn't Always Hop

Newsy (Oct. 16, 2014) Researchers believe an extinct kangaroo species weighed 500 pounds or more and couldn't hop. Video provided by Newsy
Powered by NewsLook.com
Hurricane Gonzalo Is A Category 4 And Heading To Bermuda

Hurricane Gonzalo Is A Category 4 And Heading To Bermuda

Newsy (Oct. 16, 2014) Powerful hurricane could hit Bermuda this weekend, and even if it misses it will likely do some damage. Video provided by Newsy
Powered by NewsLook.com
The Largest Volcano In Centuries Is Spewing Toxic Gas

The Largest Volcano In Centuries Is Spewing Toxic Gas

Newsy (Oct. 16, 2014) One of the largest volcanic eruptions in centuries is occurring on Iceland. The volcano Bardarbunga is producing high levels of sulfur dioxide. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins