Climate changes are linked between Greenland and the Antarctic
Even if climate records from Greenland and Antarctic ice cores look different, climate of Artic and Antarctic are directly linked. Investigations of an Antarctic ice core indicate a principle connection between both hemispheres by a 'bipolar seesaw'. Even shorter and weaker temperature changes in the south are connected to fast changes in temperature in the north by change of ocean currents in the Atlantic ocean. Antarctica always warmed in the time period 10,000 to 55,000 years BP whilst the North remained cold.
Concurrently, warm water export from the Southern Ocean to the North Atlantic was reduced. In contrast, the Antarctic started to cool every time more warm water started to flow into the North Atlantic during warm events in the north. This result suggests a general link between long-term climate changes in both hemispheres via this Bipolar Seesaw as a result of Atlantic Meridional Overturning Circulation changes. The Atlantic circulation is an important issue in the global warming debate, as icecap melt water can weaken the Atlantic currents. The research project:
In the current issue of Nature, a joint effort of scientists from 10 European nations working together in the European Project for Ice Coring in Antarctica (EPICA) established a precise link between climate records from Greenland and Antarctica using data on global changes in methane concentrations derived from trapped air bubbles in the ice. The Antarctic ice core analyses were performed on the new EDML (EPICA Dronning Maude Land) ice core, which due to its higher snow accumulation rate allows for reconstruction of higher resolution atmospheric and climate records than previous ice cores from the East Antarctic plateau; a prerequisite for precise synchronisation with the Greenland counterpart.
The Greenland ice core analyses were performed on the North Greenland Ice core Project (NGRIP). Based on the new synchronized time scale the scientists were able to compare high-resolution temperature proxy records from north and south. This showed that the Bipolar Seesaw occurred throughout and most probably beyond the last glacial period. "It is really astounding how systematically heat is moved between the north and south hemisphere with the Seasaw, causing really dramatic climate changes during the glacial period. It is one of our goals in our new Centre for Interglacial Climate to investigate the importance of this Bipolar Seasaw in our present warm climate", says the Danish researchers from the Ice and Climate group at the Niels Bohr Institute, University of Copenhagen.
The study synchronises the work of EPICA scientists from 10 European countries: Belgium, Denmark, France, Germany, UK, Italy, the Netherlands, Norway, Sweden and Switzerland. „This study is a good example of scientist from different disciplines of ice core research and glaciology collaborating internationally. Modellers, isotope specialists and glaciologists are bringing together their expertise", says Prof. Dr Heinz Miller, head of the EPICA steering committee. As the Danish partner within EPICA, The Ice and Climate group has shipped the NGRIP deep drill to Antarctic every season and has taken part in the analyses on the EDML ice core.
Anne Dorte Bach | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
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...
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...
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...
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...
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...