Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Nitrous oxide record sheds light on glacial carbon dioxide

15.08.2003


A 106,000-year-long record of nitrous oxide concentrations and a shorter record of nitrogen and oxygen isotopes show that both marine and terrestrial nitrous oxide production increased in unison and effectively by the same proportional amount during the end of the last glacial period, according to Penn State researchers.



Equal terrestrial and marine production of nitrous oxide also suggest that increased storage of carbon in the oceans was not the cause of low atmospheric carbon dioxide during ancient glacial periods, the researchers report in today’s (Aug. 15) issue of Science.

“Nitrous oxide is a greenhouse gas, but there is so little of it in the atmosphere, that it hardly contributes to climate change through changes in the radiation budget,” says Dr. Todd Sowers, research associate in geosciences. “Changes in nitrous oxide loading can, however, provide clues about systems that control carbon dioxide in the atmosphere.”


Sowers, working with Dr. Richard B. Alley, the Evan Pugh professor of geosciences, and Jennifer Jubenville, former graduate student, looked at nitrous oxide from the Greenland Ice Core Project II ice core to catalog atmospheric nitrous oxide concentrations through time.

“This is a new record of concentration variations back this far, only a small portion had been done before” says Sowers. “We found a 40 percent increase in the concentration of nitrous oxide in the atmosphere as the Earth warmed at the end of the last glacial period.”

The concentration data alone shows how much nitrous oxide was in the atmosphere at any particular time. It cannot, however, suggest how much of that gas came from the oceans or land. The researchers also looked at an ice core from the Taylor Dome, Antarctica, to create a 30,000-year history of the isotopic composition of the nitrogen and oxygen in the nitrous oxide.

Bacteria on land and in the oceans produce nitrous oxide in one of two ways. Ocean bacteria tend to create nitrous oxide that has more of the heavier isotopes of nitrogen and oxygen, while terrestrial bacteria tend to produce nitrous oxide with the lighter atoms. By looking at proportions of isotopes in the trapped gases, the researchers could determine how much was made on land and how much in the oceans.

“Before we had the isotope records, common wisdom suggested changes in terrestrial emission were probably the major player responsible for the observed concentration changes,” says Sowers. “Our isotope data, however, show that both oceanic and terrestrial emissions changed in roughly the same proportion throughout the last 30,000 years.”

Carbon dioxide in the atmosphere hits lows during glacial periods and some researchers have suggested that increased productivity in the glacial oceans could have removed carbon dioxide from the atmosphere. If the oceans behaved as they do today, then increased oceanic productivity during the glacial period would have produced elevated oceanic nitrous oxide production. However, if the relationship between terrestrial and marine nitrous oxide did not change, then this cannot be an explanation for the low levels of carbon dioxide in the atmosphere during glacial periods.

“When we thought terrestrial emissions were the dominant control on atmospheric nitrous oxide concentrations, then this hypothesis could have been true,” says Sowers. “Now that we know that the land and oceans contributed equally, we have to look for another explanation for the low carbon dioxide levels.”

A’ndrea Messer | Pennstate Un iversity
Further information:
http://live.psu.edu/story/3770

More articles from Earth Sciences:

nachricht New Technique for Finding Weakness in Earth’s Crust
30.09.2016 | University of Adelaide

nachricht Researcher creates a controlled rogue wave in realistic oceanic conditions
30.09.2016 | Aalto University

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-Ever 3D Printed Excavator Project Advances Large-Scale Additive Manufacturing R&D

Heavy construction machinery is the focus of Oak Ridge National Laboratory’s latest advance in additive manufacturing research. With industry partners and university students, ORNL researchers are designing and producing the world’s first 3D printed excavator, a prototype that will leverage large-scale AM technologies and explore the feasibility of printing with metal alloys.

Increasing the size and speed of metal-based 3D printing techniques, using low-cost alloys like steel and aluminum, could create new industrial applications...

Im Focus: New welding process joins dissimilar sheets better

Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of light metals.
Scientists at the University of Stuttgart have now developed two new process variants that will considerably expand the areas of application for friction stir welding.
Technologie-Lizenz-Büro (TLB) GmbH supports the University of Stuttgart in patenting and marketing its innovations.

Friction stir welding is a still-young and thus often unfamiliar pressure welding process for joining flat components and semi-finished components made of...

Im Focus: First quantum photonic circuit with electrically driven light source

Optical quantum computers can revolutionize computer technology. A team of researchers led by scientists from Münster University and KIT now succeeded in putting a quantum optical experimental set-up onto a chip. In doing so, they have met one of the requirements for making it possible to use photonic circuits for optical quantum computers.

Optical quantum computers are what people are pinning their hopes on for tomorrow’s computer technology – whether for tap-proof data encryption, ultrafast...

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Paper – Panacea Green Infrastructure?

30.09.2016 | Event News

HLF: From an experiment to an establishment

29.09.2016 | Event News

European Health Forum Gastein 2016 kicks off today

28.09.2016 | Event News

 
Latest News

First-Ever 3D Printed Excavator Project Advances Large-Scale Additive Manufacturing R&D

30.09.2016 | Materials Sciences

New Technique for Finding Weakness in Earth’s Crust

30.09.2016 | Earth Sciences

Cells migrate collectively by intermittent bursts of activity

30.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>