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 Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle
22.06.2018 | Technical University of Denmark

nachricht Polar ice may be softer than we thought
22.06.2018 | Eberhard Karls Universität Tübingen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>