Eruption of Bardarbunga volcano in Iceland spread SO2 pollutants over Europe
- Date:
- July 20, 2015
- Source:
- European Association of Geochemistry
- Summary:
- The six month long eruption of the Bardarbunga volcano from August 2014 to February 2015, released more SO2 that was released in Europe in the whole of 2011, and enough lava to cover Manhattan Island.
The six month long eruption of the Bardarbunga volcano (31 August 2014?27 February 2015 ) was the largest in Iceland since the devastating Laki eruption of 1783-84, producing around 1.6 km3 of lava, covering an area equivalent to Manhattan Island.
The eruption caused total Sulphur dioxide (SO2) emissions of nearly 12m tonnes, which exceeded the total SO2 emitted in Europe in 2011. In Iceland, concentration of SO2 exceeded the 350 µg m-3 hourly average health limit over much of the country for days to weeks. However, the effects of the volcano were not confined to Iceland -- many parts of Europe also saw high SO2 levels.
Researchers were initially concerned that the SO2 emissions would be much higher, which would have caused serious health problems throughout Iceland and perhaps Europe.
Lead researcher, Professor Sigurdur Gislason (University of Iceland) said, 'In the end we were lucky, but at the end of September we were getting pretty scared. Eight thousand years ago -- which is nothing in geological time -- Bardarbunga experienced an eruption even bigger than that of the 1783-84 Laki eruption. So knowing the history, we were worried that we would see a comparable event. Laki killed around 10,000 people in Iceland (20% of the Icelandic population), and the resultant SO2 pollution is thought to have affected tens of thousands in Europe, especially in the Britain, France and the Netherlands'
Writing in the peer-reviewed journal Geochemical Perspectives Letters (the journal of the European Association of Geochemistry), a group of Icelandic researchers has detailed the environmental effects of the Bardarbunga eruption.
Working in Iceland, and with environment agencies in several European countries, they were able to show that the SO2 levels rose significantly in the wake of the eruption. Monitoring stations in Ireland showed high SO2 spikes, with SO2 levels exceeding the European limits for the protection of human health on 6th September. Even at an altitude of 1210 meters in the Austrian Alps, SO2 levels spiked at 235 µg m-3. This is around 60% of permitted levels, and nearly 50 times the normal background level of around 5 µg m-3
The researchers stress that for most of Europe, the effects on health would have been minimal, given that the SO2 exposure was not prolonged.
According to lead Sigurdur Gislason: 'This was the biggest volcanic eruption in Iceland since the Laki eruption 200 years ago, which was an order of magnitude bigger. In 2014-15 most of Iceland, especially North Iceland, experienced gas pollution. However this was away from most inhabited areas.
We were also lucky with the timing, and with the weather, which tended to minimize the overall effects in Iceland, but also elsewhere on mainland Europe. The average wind speed is higher in winter than summer, thus the Bardarbunga eruption produced fast-dispersing plumes. Because of reduced autumn-winter sunlight hours, a smaller per cent of emitted SO2 had the potential to be oxidised under dry conditions to H2SO4 -- sulphuric acid. During winter there is therefore greater environmental and human health risk from SO2 than from sulphuric acid aerosol particles due to reduced conversion efficiency, whereas in summer the aerosol particle effects may dominate.
Speaking to the EAG, Dr Anja Schmidt from the University of Leeds said "This eruption presented a truly remarkable opportunity for the scientific community to better understand and quantify how such large sulfur dioxide emissions affect regional climate, the environment and human health. Gislason and co-workers present several important datasets ranging from petrological estimates of the volcanic gas emissions to the degree of acidification of the environment. These data will be of great value to the scientific community and for future studies of this eruption."
Story Source:
The above post is reprinted from materials provided by European Association of Geochemistry. Note: Materials may be edited for content and length.
Journal Reference:
- S.R Gíslason, G. Stefánsdóttir, M.A. Pfeffer, S. Barsotti, Th. Jóhannsson, I. Galeczka, E. Bali, O. Sigmarsson, A. Stefánsson, N.S. Keller, Á. Sigurdsson, B. Bergsson, B. Galle, V.C Jacobo, S. Arellano, A. Aiuppa, E.B. Jónasdóttir, E.S. Eiríksdóttir, S. Jakobsson, G.H. Guðfinnsson, S.A. Halldórsson, H. Gunnarsson, B. Haddadi, I. Jónsdóttir, Th. Thordarson, M. Riishuus, Th. Högnadóttir, T. Dürig, G.B.M. Pedersen, Á. Höskuldsson, M.T. Gudmundsson. Environmental pressure from the 2014–15 eruption of Bárðarbunga volcano, Iceland. Geochemical Perspectives Letters, 2015; 84 DOI: 10.7185/geochemlet.1509
Scientists Record Explosion at Alaska's Cleveland Volcano
An explosion Tuesday morning rocked Alaska's Cleveland Volcano but scientists have detected no ash cloud that could threaten jets crossing the Pacific Ocean.
Scientists as the Alaska Volcano Observatory recorded an explosion at the volcano 940 miles southwest of Anchorage in the Aleutian Islands.
U.S. Geological Survey geologist Kristi Wallace said a similar explosion was recorded in November. Ash may have been produced but likely stayed under 20,000 feet, she said.
"We see this quite often and we think that they are associated with some sort of ash production," she said.
Clouds obscured the sky at 30,000 feet. The observatory detected no ash above the clouds.
The Federal Aviation Administration and the airline industry become concerned for trans-Pacific flights when an ash cloud has the potential to exceed 20,000 feet.
Alaska's Redoubt Volcano blew on Dec. 15, 1989, and sent ash 150 miles away into the path of a KLM jet carrying 231 passengers. Its four engines flamed out. The jet dropped more than 2 miles, from 27,900 feet to 13,300 feet, before the crew restarted all engines and landed the plane safely at Anchorage.
Cleveland Volcano is within 5,675-foot Cleveland Mountain, a nearly symmetrical peak that looks like an inverted V.
Cleveland Volcano forms the western part of Chuginadak Island and is 45 miles west of tiny Nikolski and its 15 permanent residents on Umnak Island. In previous eruptions, the village was not threatened by as the plume dispersed in other directions.
The volcano experienced a significant eruption in February 2001. Three explosive events generated ash as high as 39,000 feet. The eruption also sent out lava and a hot avalanche that reached the ocean.
In the last 14 years, Cleveland Volcano has occasionally produced small lava flows and explosions with small ash clouds below 20,000 feet. The explosions have launched debris onto the slope of the cone and sometimes hot avalanches.
Colima volcano (Mexico) July 2015 photos: evacuations and Monte Grande pyroclastic flow
http://www.volcanodiscovery.com/colima/photos/july2015/pyroclastic-flow.html
Iridescent Pools Discovered in Undersea Volcano's Crater
 |
 Using underwater vehicles, the international team discovered the pools in the crater of the Santorini volcano.Credit: Rich Camilli, Woods Hole Oceanographic Institution |
Deep in the Aegean Sea, shimmering pools of white water meander through the caldera of the Santorini volcano.
Never seen before, these opalescent pools — called Kallisti Limnes, from ancient Greek for "most beautiful lakes" — appear in a new video taken by underwater vehicles in July 2012. They contain high levels of carbon dioxide, which may make the water dense and prone to pooling.
"What we have here is like a 'black and tan' — think Guinness and Bass [Ale] — where the two fluids actually remain separate," said Rich Camilli, a scientist at Woods Hole Oceanographic Institution (WHOI) and the lead author of a study on the phenomenon published July 16 in the journal Scientific Reports. (A black and tan is a layered drink made by mixing light and dark beers.)
"The volcanic eruption at Santorini in 1600 B.C. wiped out the Minoan civilization living along the Aegean Sea," Camilli said in a statement. "Now these never-before-seen pools in the volcano's crater may help our civilization answer important questions about how carbon dioxide behaves in the ocean." [See Photos of the Iridescent Pools in the Aegean Sea]
The picturesque Greek island of Santorini, or Thira, is actually the edge of an enormous caldera left behind after the eruption. Within this caldera are spots of hydrothermal activity. It was these spots that Camilli and his colleagues were investigating in 2012, a year after the caldera showed signs of increasing volcanic activity. (The unrest has since calmed.)
Using two autonomous underwater vehicles, the researchers explored the chemistry of the water in the caldera. They discovered the milky carbon dioxide-rich pools in depressions along the caldera wall.
The water in the ocean is not an undifferentiated mass — in fact, researchers have previously observed brine pools that separate out from surrounding ocean water because of extra-high salt content, Camilli said.
"In this case, the pools' increased density isn't driven by salt," Camilli said. "We believe it may be the CO2 itself that makes the water denser and causes it to pool."
The observation is intriguing, because carbon dioxide was thought to diffuse through the ocean after being released from geologic activity. Underground carbon dioxide can come from magma or from limestone or other sedimentary rocks under tremendous pressure.
Because of the carbon dioxide, the pools were high in acidity. They may, however, host silica-based organisms, whose glassy microscopic bodies could explain the opal hue, the researchers reported.
The findings could help researchers understand how undersea calderas behave. They might also have implications for carbon capture and storage, one potential way to ameliorate climate change. Some scientists have suggested capturing carbon and trapping it under the seafloor in order to keep it out of the atmosphere (and out of the ocean, where its acidifying properties make it a danger to sea life). But little is known about how subsurface carbon dioxide behaves, or what might happen if the carbon leaks out of the ground.
http://www.livescience.com/51613-iridescent-pools-discovered-in-aegean-sea.html
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