Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Climate Change: The Past of the Atlantic Heat Pump

16.10.2012
The circulation of the Atlantic Ocean was faster during the last Ice Age than today

Heat transport in the Atlantic Ocean during the last Ice Age was not weaker, as long assumed, but in fact stronger than it is today. This discovery was made by an international research team led by environmental physicists at Heidelberg University.

The scientists used ultra-precise measurements of natural radionuclides in ocean sediments to study the ocean’s strength of circulation and uncovered new information about the past of the “Atlantic heat pump”. The results of their research, which are also significant for correctly predicting climate models, were published in the journal “Nature Geoscience”.

“Thanks to the Gulf Stream and its northern branches, it is much warmer here than at the same latitudes in North America. Without the ocean’s heat transport, which is comparable to that of a million large power plants, temperatures in Northern and Western Europe would be considerably cooler”, explained Dr. Jörg Lippold, lead author of the study from Heidelberg University‘s Institute of Environmental Physics. Europe’s heating system originates in the Gulf of Mexico, where the waters of the ocean warm and flow northeast due to wind and the Earth’s rotation. The water at the surface cools in the process, growing denser, and then sinks in the North Atlantic, where it flows south again in the Ocean’s depths.

“Using two exotic representatives of the periodic table from core samples of Atlantic deep sea sediment, we were able to quantitatively determine this return flow for the first time”, said the Heidelberg researcher. The two isotopes studied, protactinium-231 and thorium-230, are produced from the radioactive decay of uranium found naturally in sea water. While thorium is deposited directly in the sediment at the Ocean’s floor, the protactinium follows the circulation and is carried by the deep sea current from the North Atlantic. The proportion of the two elements in the sediment ergo reflects the strength of the circulation. Around the time of the largest global ice coverage approximately 20,000 years ago, less proctactinium-231 was measured. According to Dr. Lippold, this points to an increase in the Atlantic circulation, which is also supported by model calculations.

Knowing that the Atlantic circulated faster during the Ice Age is important for models used to calculate the future of the world’s climate. The accuracy of the predictions of climate models is assessed in particular by whether they correctly reflect the climate in the past. “The oceans are the key to the Earth’s climate system. There is approximately 50 times more CO2 bound in the Earth’s Oceans than in the atmosphere, with 1,000 times more heat storage capacity“, said Dr. Lippold. “With the Ocean circulating more quickly then, it could also extract and store more CO2 from the atmosphere.”

Understanding these relationships has special significance for major parts of Europe. “If the Ocean warms in the course of climate change and the density of the waters of the North Atlantic drops due to melt water or increased precipitation, the heat pump could weaken. Paradoxically, this could cause cooling in Europe while the rest of the world heats up”, explained the Heidelberg environmental physicist.

The international team’s large-scale study was based on measurements using mass spectrometers and particle accelerators, which were able to detect the required concentrations of a few picograms. The study led by Dr. Jörg Lippold included researchers from Vancouver, Paris, Oxford, Zürich, Lyon, Bristol and Tübingen. Germany’s support of the project came from the German Research Foundation. For more information, go to www.iup.uni-heidelberg.de/institut/forschung/groups/fa/marine

Original publication:
Jörg Lippold, Yiming Luo, Roger Francois, Susan E. Allen, Jeanne Gherardi, Sylvain Pichat, Ben Hickey, Hartmut Schulz: Strength and geometry of the glacial Atlantic Meridional Overturning Circulation. Nature Geoscience (14 October 2012), doi 10.1038/ngeo1608

Contact:
Dr. Jörg Lippold
Institute of Environmental Physics
Phone: +49 6221 54-6385
joerg.lippold@iup.uni-heidelberg.de

Communications and Marketing
Press Office, phone: +49 6221 54-2311
presse@rektorat.uni-heidelberg.de

Marietta Fuhrmann-Koch | idw
Further information:
http://www.uni-heidelberg.de

More articles from Earth Sciences:

nachricht Early organic carbon got deep burial in mantle
25.04.2017 | Rice University

nachricht New atlas provides highest-resolution imagery of the Polar Regions seafloor
25.04.2017 | British Antarctic Survey

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Early organic carbon got deep burial in mantle

25.04.2017 | Earth Sciences

A room with a view - or how cultural differences matter in room size perception

25.04.2017 | Life Sciences

Warm winds: New insight into what weakens Antarctic ice shelves

25.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>