Friday, 23 June 2017

Research shows the seabed has become much warmer

Örjan Gustafsson (Google translate):

"Our measurements showed that the seabed has become much warmer. At the end of the Ice Age was the temperature on the seabed -18 degrees. Now it is about 0 degrees. We also explored the line between frozen and thawed permafrost in the seabed and could see that this limit lies at 10-30 meters depth, and the limit drops quickly. The permafrost thaws by an average of 14 cm a year now and then 4 meters in the last 30 years."


The arctic permafrost is thawing faster than previously thought
Arktis permafrost tinar snabbare än vad som tidigare är känt



22 June, 2017

Permafrost in the seabed in the World, the arctic ocean thaws now with an average of 14 cm per year. It is much more than what you've previously known, and the process threatens to amplify global warming, according to a new study from Stockholm university which is published today in the scientific journal Nature Communications.

It is a huge area that is now thaws, it is as large as four times the Baltic sea, " says Örjan Gustafsson, professor in biogeochemistry at the Department of environmental science and analytical chemistry (ACES), Stockholm university, which is one of the authors behind the study.
He has in several research projects and expeditions investigated the conditions in the Arctic seas in order to, inter alia, note the changes of not only the carbon stored in the permafrost, as it's usually called ”the sleeping giants”. If this carbon is released levels of carbon dioxide and methane in the atmosphere which increases the warming of the climate.
Örjan Gustafsson and the research group's latest study is based on observations that have been made over the years 2011-2015 in kusthavet off the north-east Siberia.
We had a isläger there and was out with vehicles and rigs on the sea ice in order to drill down to the permafrost in the seabed.
The cores of sediment could then be compared with surveys carried out in the same places 30 years ago.
Our measurements showed that the seabed has become much warmer. At the end of the ice age was the temperature on the seabed -18 degrees. Now, it is approximately 0 degrees. We also investigated the boundaries between frozen and unfrozen permafrost in the seabed and were able to see that this limit is set at 10-30 meters deep, and the limit drops quickly. The permafrost thaws with an average of 14 cm per year now and that is 4 metres in the last 30 years.
Permafrost is the constantly frozen soil that consists of decomposed organic material, and already the format of methane; moreover, when a heating also of methane in the form of natural gas released when permafrostlagret weakened.
"Previously, the natural gas held in place by the permafrost that has formed over it as a lid, but now when the permafrost thaws and becomes perforated as create channels and then gas is released," says Örjan Gustafsson, who argue that the latest study is important in order to understand the processes occurring in the arctic seabed.
For the first time, we have been able to observe how permafrost is constructed in the seabed, the temperature and how quickly it thaws. If these processes affect the global warming, it is important to take the height for it and prepare society for it development, " says Örjan Gustafsson.
About the study:

Natalia Shakhova, Igor Semiletov, Örjan Gustafsson, Valentin Sergienko, Leopold Lobkovsky, Oleg Dudarev, Vladimir Tumskoy, Michael Grigoriev, Alexey Mazurov, Anatoly Salyuk, Roman Ananiev, Andrey Koshurnikov, Denis Kosmach, Alexander Charkin, Nicolay Dmitrevsky, Victor Karnaukh, Alexey Parking, Alexander Meluzov & Denis Chernykh, 2017: “Current rates and mechanisms of subsea permafrost degradation in the East Siberian Arctic Shelf”, Nature Communications.
Link to the article in Nature Communications:
Contact:

Örjan Gustafsson, 070-324 73 17, orjan.gustafsson@aces.su.se

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