Navigation Links
Improved interpretation of volcanic traces in ice
Date:7/8/2013

Storms, cold, poor harvests -- the year 1816 was a "year without a summer" in European history. The reason was the eruption of the Indonesian volcano Tambora a year earlier. It had thrown huge amounts of sulfur compounds into the stratosphere (at altitudes of 15-50 km) where they spread around the entire globe and significantly weakened solar radiation for several years afterwards. Such intense volcanic eruptions are quite common in Earth's history. To better understand their impact on the climate and the atmosphere, scientists try to reconstruct those eruptions accurately. Important archives of information are ice cores from Greenland and Antarctica because the sulfur particles ejected from the volcano fall back to the surface. A portion of that fallout is trapped in the ice of the polar regions and can be analyzed even thousands of years afterwards. The former aerosol contamination of the atmosphere is derived from it using a simple ratio calculation.

But this method has its limitations. "Volcanic aerosols in the stratosphere absorb infrared radiation, thereby heating up the stratosphere, and changing the wind conditions subsequently," said Dr. Matthew Toohey, atmospheric scientist at GEOMAR Helmholtz Centre for Ocean Research Kiel. Using an atmospheric model, he has now tested the effects of this phenomenon. "We have found that the deposition of sulfur compounds in the Antarctic after very large volcanic eruptions in the tropics may be lower than previously thought," the atmospheric researcher summarizes the findings of the study which has just been published in the current issue of the international Journal of Geophysical Research Atmosphere.

For the study, Dr. Toohey and his colleagues from GEOMAR and the Max Planck Institute for Meteorology in Hamburg have used an aerosol-climate model to track 70 different eruption scenarios while analyzing the distribution of the sulfur particles. It was based on real volcanic eruptions during the past 200,000 years in Central America, which had been investigated in the framework of the Collaborative Research Project 574. "In our calculations, we could clearly see the differences in distribution and deposition between the northern and southern hemispheres," explains co-author and director of the working group, Dr. Kirstin Krger. The spatial deposition of sulfur particles in the bipolar ice cores, as calculated in the model, agrees well with the actually measured deposits of large volcanic eruptions, such as Pinatubo in 1991 or even of Tambora of 1815.

"If we know how volcanic sulfur particles affect the atmospheric winds, we can have a much improved interpretation of the traces of volcanic activities in the ice cores," says Dr. Toohey. For one, there are better estimates of the strength of an outbreak. And secondly, the previously undetermined traces of volcanic eruptions that could not be assigned to any particular event or volcano eruption, can now be clearly traced to their origin.

"In any case, the results of our model study give a clear indication that the bipolar variability of sulfate deposits must be taken into consideration if the traces of large volcanic eruptions are to be deduced from ice cores," says Dr. Krger, "Several research groups that deal with this issue have already contacted us to verify their data through our model results."


'/>"/>

Contact: Jan Steffen
jsteffen@geomar.de
Helmholtz Centre for Ocean Research Kiel (GEOMAR)
Source:Eurekalert

Related biology news :

1. Improved Authentication and Confidentiality Protection. ICAP Patent Brokerage Announces for Auction Important Patents in Data Encryption and Document Security
2. Some improved cookstoves may emit more pollution than traditional mud cookstoves
3. Improved loblolly pines better for the environment, study finds
4. Early detection techniques offer hope for improved outcomes in lung cancer patients
5. Trial seeks improved lung-cancer screening by combining imaging and biomarkers
6. A trained palate: Understanding complexities of taste, smell could lead to improved diet
7. How alert hospital employees improved hospitals MSRA infection rate
8. 3-D motion of cold virus offers hope for improved drugs using Australias fastest supercomputer
9. Ship-borne measurements show EU policies have improved air quality in harbors
10. Glass offers improved means of storing UKs nuclear waste
11. Nutrition tied to improved sperm DNA quality in older men
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... BANGALORE, India , April 28, 2016 /PRNewswire/ ... product subsidiary of Infosys (NYSE: INFY ), and ... global partnership that will provide end customers with ... banking and payment services.      (Logo: http://photos.prnewswire.com/prnh/20130122/589162 ... area for financial services, but it also plays a fundamental ...
(Date:4/26/2016)... LONDON , April 26, 2016 /PRNewswire/ ... Systems, a product subsidiary of Infosys (NYSE: ... partnership to integrate the Onegini mobile security platform ... http://photos.prnewswire.com/prnh/20151104/283829LOGO ) The integration ... security to access and transact across channels. Using ...
(Date:4/19/2016)... , UAE, April 20, 2016 ... be implemented as a compact web-based "all-in-one" system solution ... the biometric fingerprint reader or the door interface with ... of modern access control systems. The minimal dimensions of ... ID readers into the building installations offer considerable freedom ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... ... will join the faculty of the University of North Carolina Kenan-Flagler Business ... strategy and entrepreneurship at UNC Kenan-Flagler, with a focus on the school’s international ...
(Date:6/24/2016)... NY (PRWEB) , ... June 24, 2016 , ... While ... machines such as the Cary 5000 and the 6000i models are higher end machines ... is the height of the spectrophotometer’s light beam from the bottom of the cuvette ...
(Date:6/23/2016)... TORONTO , June 23, 2016 /PRNewswire/ - ... Ontario biotechnology company, Propellon ... the development and commercialization of a portfolio of ... cancers. Epigenetic targets such as WDR5 represent an ... contribute significantly in precision medicine for cancer patients. ...
(Date:6/23/2016)... , June, 23, 2016  The Biodesign Challenge (BDC), ... new ways to harness living systems and biotechnology, announced ... (MoMA) in New York City . ... participating students, showcased projects at MoMA,s Celeste Bartos Theater ... Antonelli , MoMA,s senior curator of architecture and design, ...
Breaking Biology Technology: