Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UF research gives clues about carbon dioxide patterns at end of Ice Age

26.10.2010
New University of Florida research puts to rest the mystery of where old carbon was stored during the last glacial period. It turns out it ended up in the icy waters of the Southern Ocean near Antarctica.

The findings have implications for modern-day global warming, said Ellen Martin, a UF geological sciences professor and an author of the paper, which is published in this week’s journal Nature Geoscience.

“It helps us understand how the carbon cycle works, which is important for understanding future global warming scenarios,” she said. “Ultimately, a lot of the carbon dioxide that we’re pumping into the atmosphere is going to end up in the ocean. By understanding where that carbon was stored in the past and the pathways it took, we develop a better understanding of how much atmospheric carbon dioxide the oceans can absorb in the future.”

Scientists know that during the transition from the last glacial period to the current inter-glacial period about 14,000 years ago, carbon dioxide levels rose very quickly at the same time that the age of the carbon dioxide in the atmosphere fell, as measured by radiocarbon data. That suggests carbon dioxide had been stored in the ocean and suddenly released, she said.

One idea holds that it was building up in the Southern Ocean around Antarctica, where extensive sea ice on the surface of the ocean initially prevented the exchange of gasses into the atmosphere, Martin said. The other possibility is that the same process occurred in the Northern Hemisphere with ice sheets in the North Pacific Ocean, she said.

In her lab, Martin and lead author Chandranath Basak, a UF graduate student in geological sciences; Keiji Horikawa, a UF postdoctoral fellow in geological sciences; and Thomas Marchitto, a University of Colorado geology professor, studied that question by using a technique to measure isotopes of neodymium, a rare earth element not commonly found in marine sediments but preserved in microscopic fossil fish teeth. The isotopic signature of a water mass, which is captured in the fish teeth, reflects the location where the water mass came from, she said.

“It’s essentially what we call a water mass tracer,” Martin said. “You can tell where the water masses have formed and where they have moved to by using this tracer.”

The researchers took samples that had been shown to have old carbon in them and measured the neodymium isotopes on fish teeth from the sediments to see if they could reconstruct whether they had come from the North Pacific or the Southern Ocean, she said.

“When we did this, we got a signal that looks very much like the Southern Ocean,” she said. “It implies that all the carbon was being stored in the Southern Hemisphere and as the ice sheet melted back, it released that carbon dioxide into the atmosphere, causing part of the big increase in carbon dioxide and introducing old carbon back into the atmosphere.”

By giving information about environmental conditions during the last glacial period, the research findings can help scientists to reconstruct what the world was like at that time, she said.

The implications are that while large amounts of carbon could be stored in the ocean when there was a great deal of sea ice, the opposite is the case in a world that is warming, with less ice, which allows more carbon dioxide to be released into the atmosphere, Martin said. Thus, in a warming scenario the oceans may not be able to store as much carbon dioxide as they could under glacial conditions

The oceans are a critical part of the carbon dioxide cycle, Martin said. “The oceans have 60 times more carbon dioxide in them than the atmosphere, so when we worry about what’s happening with carbon dioxide in the atmosphere, we often look to the oceans as a potential source or sink.”

The concentration of carbon dioxide in the atmosphere during the glacial periods was about 200 parts per million, compared with 280 parts per million during a typical interglacial period, Martin said. Today that level has soared to about 380 parts per million, she said.

The time period that encompasses the last glacial period to the current interglacial period when carbon dioxide levels went up very quickly is often referred to as the “mystery interval” because scientists hadn’t known where the carbon was stored, Martin said.

“Now we have a better understanding of how the system worked,” she said.

Writer
Cathy Keen, ckeen@ufl.edu, 352-392-0186
Source
Ellen Martin, eemartin@ufl.edu, 352-392-2141

Ellen Martin | EurekAlert!
Further information:
http://www.ufl.edu

More articles from Earth Sciences:

nachricht Supercomputing helps researchers understand Earth's interior
23.05.2017 | University of Illinois College of Liberal Arts & Sciences

nachricht How is climate change affecting fauna in the Arctic?
22.05.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

Im Focus: Bacteria harness the lotus effect to protect themselves

Biofilms: Researchers find the causes of water-repelling properties

Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

Scientists propose synestia, a new type of planetary object

23.05.2017 | Physics and Astronomy

Zap! Graphene is bad news for bacteria

23.05.2017 | Life Sciences

Medical gamma-ray camera is now palm-sized

23.05.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>