Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

LSU professor uses volcanic emissions to study Earth's atmospheric past

17.06.2010
On March 20, Iceland's Eyjafjallajokull volcano woke from its nearly 200-year slumber to change the way the world viewed volcanoes forever. Bringing almost all transatlantic air travel to a halt for the first time in modern history, this volcano reminded humanity of the powers these forces of nature contain – and of our relative inability to understand them. Associate Professor Huiming Bao of LSU's Department of Geology & Geophysics has published research in the journal Nature about massive volcanic eruptions and their atmospheric consequences in the past in North America.

"Past volcanic eruptions have had significant impacts on the environment," said Bao. "We humans have witnessed the various impacts of volcanic eruptions like the 1991 Mount Pinatubo and the more recent Icelandic one. The physical aspect of the impacts such as explosion or ash plumes is often short-lived, but the chemical consequence of its emitted massive gases can have a long-lasting effect on global climate."

The paper, titled "Massive Volcanic SO2 Oxidation and Sulfate Aerosol Deposition in Cenozoic North America," represents research into the Earth's climactic past. Using computer models and geological data, Bao and his colleagues, Shocai Yu of the EPA and Daniel Tong of the National Oceanic and Atmospheric Administration, or NOAA, were able to simulate the sulfur gas oxidation chemistry and atmospheric condition of the northern high plains region of North America long before human activities began significantly impact the air quality. Yu and Tong contributed to the modeling aspect of the study. They used a state-of-the-art atmospheric sulfur chemistry and transport model to simulate the atmospheric conditions necessary for the observed sulfate isotope data preserved in rock records.

Bao and his colleagues discovered that many of the volcanic ash beds are rich in sulfate, the product of atmospheric oxidation of sulfur gases. Most importantly, these sulfates have distinct stale isotope signatures that can tell how they were formed in the atmosphere, particularly which oxidation pathways they went through. In order to explain their geological data, they did an extensive modeling test and found that it is imperative to have an initial alkaline cloudwater pH condition, which rarely exists in modern days.

According to Bao, the most important volcanic gas – as far as atmospheric implications go – is sulfur dioxide, or SO2. This gas is oxidized in the atmosphere, where it is turned into sulfate aerosol, which plays a very sensitive role in the rate and impact of climate change. When the sulfate aerosol is dense or long-lasting and the depositional condition is right, the sulfate aerosol can be preserved in rock records.

"These sulfate aerosol deposition events were so intense that the sulfate on the ground or small ponds reached saturation and gypsum mineral formed," Bao said. He pointed out that the closest analog event is perhaps the 1783 Laki eruptions of Iceland and the subsequent "dry fogs" in continental Europe. "That event devastated Iceland's cattle population. People with lung problems suffered the worst. In North America, the next year's winter was the longest and one of the coldest on record. The Mississippi River froze at New Orleans. The French Revolution in 1789 may have been triggered by the poverty and famine caused by the eruption."

These explosive eruptions are much more intense and sulfur rich than any human has ever experienced or recorded. But that doesn't mean that eruptions of such magnitude can't happen today.

"It is important to note that the volcanic eruptions we experienced in the past thousands of years are nothing compared to some of the eruptions occurred in the past 40 million years in western North America, either in the level of power or the amount of SO2 spewed," said Bao. "What we reported in our Nature paper is that there were many massive volcanic SO2 emissions and dense sulfate aerosol events in the northern High Plains of North America in the past. We show that in the past the sulfate aerosol formed in a very different way than today, indicating a difference in the past atmospheric condition or something peculiar with these explosive eruptions in the west."

NOTE: Bao is currently conducting fieldwork and will have intermittent access to communication through June.

More news and information can be found on LSU's home page at www.lsu.edu

Ashley Berthelot | EurekAlert!
Further information:
http://www.lsu.edu

More articles from Earth Sciences:

nachricht Ice cave in Transylvania yields window into region's past
28.04.2017 | National Science Foundation

nachricht Citizen science campaign to aid disaster response
28.04.2017 | International Institute for Applied Systems Analysis (IIASA)

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

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | 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

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>