Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cardiac fibrillation of the climate

18.02.2009
Rapid decadal climate change before the start of the Holocene

In the current issue of the Scientific Journal Nature Geoscience a group of Norwegian, Swiss and German geoscientists prove that before the set-in of the Holocene very rapid climate changes already existed. The transition from the stable cold period took place about 12 150 to 11 700 years ago with very rapid fluctations up to the temperatur-threshold at which the Holocene began.

For this study, a group of scientists around J. Bakke, University of Bergen, examined sediments from Lake Kråkenes in Southwest Norway. These micro-layered lake deposits constitute a particularly suitable geological archive, with which scientists are able to analyse the climate volatility. The geochemical determination of titanium in sediments shows that during this phase significant short-term fluctuations in the titanium concentrations in the lake are detectable.

"We ascribe this to the short-term fluctuations in watermelt runoff from the inland glacier which feeds this lake", explains Professor Gerald Haug from the DFG Leibniz Center for Earth Surface Process and Climate Studies at the University of Potsdam and the ETH Zürich, who carried out the analysis together with his colleague, Peter Dulkski, from the GFZ German Research Centre for Geosciences. "The fluctuating glacialmelt is a result of the intermittent advancement of the Gulf Stream and the resulting successive retreat of the sea-ice coverage."

This process is closely linked with an equally high-frequence change in the westwind system and the therewith connected heat transport to Europe. This cardiac fibrillation of the climate is reflected again, as shown, in the fast-varying meltwater runoff into the examined lake, which at this point in time actually lay at the most climate-sensitive location of Europe, namely there where the Gulf Stream and the sea-ice coverage transformed.

* J. Bakke, Ø. Lie, E. Heegaard, T. Dokken, G. Haug, H. Birks, P. Dulski and T. Nilsen: (2009): Rapid oceanic and atmospheric changes during the Younger Dryas cold period, Nature Geoscience, Advance Online Publication, 15.02. 2009, 18:00 London time

Franz Ossing | EurekAlert!
Further information:
http://www.gfz-potsdam.de

More articles from Earth Sciences:

nachricht New research calculates capacity of North American forests to sequester carbon
16.07.2018 | University of California - Santa Cruz

nachricht Scientists discover Earth's youngest banded iron formation in western China
12.07.2018 | University of Alberta

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Microscopic trampoline may help create networks of quantum computers

17.07.2018 | Information Technology

In borophene, boundaries are no barrier

17.07.2018 | Materials Sciences

The role of Sodium for the Enhancement of Solar Cells

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>