Possible seismogenic trigger mechanism of abrupt activation of methane emission and climate warming in the Arctic

A seismogenic trigger mechanism is proposed to explain the abrupt climate warming phases in the Arctic as a result of strong mechanical disturbances in the marginal region of the Arctic lithosphere. Those disturbances might have been caused by great earthquakes in the Aleutian subduction zone, and slowly propagated across the Arctic shelf and adjacent regions, triggering the methane release from permafrost and metastable gas hydrates, followed by greenhouse gas emissions into the atmosphere. The proposed mechanism is based on the identified correlation between the series of the great earthquakes in the Aleutian island arc, which occurred in the early and middle of the 20th century, and the two phases of sharp climate warming, which began in 1920 and 1980. There is a 20-year time lag between these events, which is explained by the time of arrival of deformation waves in the lithosphere (propagating with a velocity of about 100 km per year) at the Arctic shelf and adjacent land from the Aleutian subduction zone, the region of their generation. The trigger mechanism causing the methane release from permafrost and metastable gas hydrates is related to the destruction of micro-sized ice films covering gas hydrate particles, the elements highly important for hydrate self-preservation, as well as destruction of gas-saturated micropores in permafrost rocks due to the slight additional stresses associated with deformation waves, and thus emergence of conditions favorable for gas filtration and its subsequent emission.

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A new Antarctic foraminiferal species for detecting climate change in sub-Recent glacier-proximal sediments

Antarctic Science ◽

10.1017/s0954102009990150 ◽

2009 ◽

Vol 21 (5) ◽

pp. 439-448 ◽

Cited By ~ 10

Author(s):

Wojciech Majewski ◽

Andrzej Tatur

Keyword(s):

Climate Change ◽

Climate Warming ◽

The Arctic ◽

South Shetland Islands ◽

King George Island ◽

Tidewater Glaciers ◽

Admiralty Bay ◽

Shetland Islands ◽

Foraminiferal Species ◽

Water Depths

AbstractCribroelphidium webbi sp. nov. is the only adequately described sub-Recent elphidiid foraminifer from Antarctica. In Admiralty Bay (King George Island, South Shetland Islands), it is found at several locations within inner fiord setting at water depths between 33 and 165 m, but most commonly shallower than 100 m. In outer basins this foraminifer is absent. In the cores analysed, C. webbi sp. nov. is present in well-constrained sub-Recent horizons that are clearly related to climate warming and deglaciation. These horizons represent a diachronous facies marker rather than a single stratigraphic layer. Cribroelphidium webbi sp. nov. shows clear association with retreating tidewater glaciers, therefore it is an important sensitive glacier-proximal indicator. It appears that it shares similar ecologic affinities with Cribroelphidium excavatum clavatum, which is widely distributed throughout the Arctic.

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ON METHANE EMISSION IN THE ARCTIC

Actual Problems of Oil and Gas ◽

10.29222/ipng.2078-5712.2018-23.art64 ◽

2018 ◽

Author(s):

V.V. Adushkin ◽

V.P. Kudryavtsev

Keyword(s):

Methane Emission ◽

The Arctic

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Environmental controls on ecosystem-scale cold-season methane and carbon dioxide fluxes in an Arctic tundra ecosystem

Biogeosciences ◽

10.5194/bg-17-4025-2020 ◽

2020 ◽

Vol 17 (15) ◽

pp. 4025-4042

Author(s):

Dean Howard ◽

Yannick Agnan ◽

Detlev Helmig ◽

Yu Yang ◽

Daniel Obrist

Keyword(s):

Carbon Dioxide ◽

Methane Emission ◽

Arctic Tundra ◽

Cold Season ◽

The Arctic ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Carbon Dioxide Fluxes ◽

Soil Temperatures ◽

Annual Total

Abstract. Understanding the processes that influence and control carbon cycling in Arctic tundra ecosystems is essential for making accurate predictions about what role these ecosystems will play in potential future climate change scenarios. Particularly, air–surface fluxes of methane and carbon dioxide are of interest as recent observations suggest that the vast stores of soil carbon found in the Arctic tundra are becoming more available to release to the atmosphere in the form of these greenhouse gases. Further, harsh wintertime conditions and complex logistics have limited the number of year-round and cold-season studies and hence too our understanding of carbon cycle processes during these periods. We present here a two-year micrometeorological data set of methane and carbon dioxide fluxes, along with supporting soil pore gas profiles, that provide near-continuous data throughout the active summer and cold winter seasons. Net emission of methane and carbon dioxide in one of the study years totalled 3.7 and 89 g C m−2 a−1 respectively, with cold-season methane emission representing 54 % of the annual total. In the other year, net emission totals of methane and carbon dioxide were 4.9 and 485 g C m−2 a−1 respectively, with cold-season methane emission here representing 82 % of the annual total – a larger proportion than has been previously reported in the Arctic tundra. Regression tree analysis suggests that, due to relatively warmer air temperatures and deeper snow depths, deeper soil horizons – where most microbial methanogenic activity takes place – remained warm enough to maintain efficient methane production whilst surface soil temperatures were simultaneously cold enough to limit microbial methanotrophic activity. These results provide valuable insight into how a changing Arctic climate may impact methane emission, and highlight a need to focus on soil temperatures throughout the entire active soil profile, rather than rely on air temperature as a proxy for modelling temperature–methane flux dynamics.

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New species of Scolelepis (Polychaeta, Spionidae) from the Norwegian coast and Barents Sea with a brief review of the genus

Fauna norvegica ◽

10.5324/fn.v35i0.1666 ◽

2015 ◽

Vol 35 ◽

pp. 9 ◽

Cited By ~ 2

Author(s):

Andrey Sikorski ◽

Lyudmila Pavlova

Keyword(s):

New Species ◽

Kola Peninsula ◽

Climate Warming ◽

Barents Sea ◽

Identification Key ◽

The Arctic ◽

Atlantic Sector ◽

Norwegian Coast ◽

The Barents Sea

The species Scolelepis finmarchicus sp. nov. is described from the Norwegian and Barents Seas along the northern Norwegian coast and Kola peninsula. The occurrence of this species in the Kola Bay could be seen as a sign of climate warming in the area. Taxonomic issues existing in the genus Scolelepis within the area along the Norwegian coast and in the Barents Sea are briefly touched upon. Seven species belonging to Scolelepis have recently been recorded from the Atlantic sector of the Arctic. Scolelepis (S.) matsugae Sikorski, 1994 is newly synonymized with S. (S.) laonicola (Tzetlin, 1985). This article provides a brief review of Scolelepis together with an identification key for the genus from the Atlantic sector of the Arctic

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Role of Salt Migration in Destabilization of Intra Permafrost Hydrates in the Arctic Shelf: Experimental Modeling

Geosciences ◽

10.3390/geosciences9040188 ◽

2019 ◽

Vol 9 (4) ◽

pp. 188 ◽

Cited By ~ 6

Author(s):

Evgeny Chuvilin ◽

Valentina Ekimova ◽

Boris Bukhanov ◽

Sergey Grebenkin ◽

Natalia Shakhova ◽

...

Keyword(s):

Gas Hydrates ◽

Methane Emission ◽

Gas Hydrate ◽

Negative Temperature ◽

Arctic Shelf ◽

The Arctic ◽

Permafrost Degradation ◽

Stability Zone ◽

Local Pressure ◽

Hydrate Stability

Destabilization of intrapermafrost gas hydrate is one possible reason for methane emission on the Arctic shelf. The formation of these intrapermafrost gas hydrates could occur almost simultaneously with the permafrost sediments due to the occurrence of a hydrate stability zone after sea regression and the subsequent deep cooling and freezing of sediments. The top of the gas hydrate stability zone could exist not only at depths of 200–250 m, but also higher due to local pressure increase in gas-saturated horizons during freezing. Formed at a shallow depth, intrapermafrost gas hydrates could later be preserved and transform into a metastable (relict) state. Under the conditions of submarine permafrost degradation, exactly relict hydrates located above the modern gas hydrate stability zone will, first of all, be involved in the decomposition process caused by negative temperature rising, permafrost thawing, and sediment salinity increasing. That’s why special experiments were conducted on the interaction of frozen sandy sediments containing relict methane hydrates with salt solutions of different concentrations at negative temperatures to assess the conditions of intrapermafrost gas hydrates dissociation. Experiments showed that the migration of salts into frozen hydrate-containing sediments activates the decomposition of pore gas hydrates and increase the methane emission. These results allowed for an understanding of the mechanism of massive methane release from bottom sediments of the East Siberian Arctic shelf.

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Eutrophication exacerbates the impact of climate warming on lake methane emission

The Science of The Total Environment ◽

10.1016/j.scitotenv.2018.04.283 ◽

2018 ◽

Vol 636 ◽

pp. 411-419 ◽

Cited By ~ 30

Author(s):

Armando Sepulveda-Jauregui ◽

Jorge Hoyos-Santillan ◽

Karla Martinez-Cruz ◽

Katey M. Walter Anthony ◽

Peter Casper ◽

...

Keyword(s):

Climate Warming ◽

Methane Emission ◽

The Impact

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The effects of ultraviolet-B radiation on freshwater ecosystems of the Arctic: Influence from stratospheric ozone depletion and climate change

Environmental Reviews ◽

10.1139/a04-003 ◽

2004 ◽

Vol 12 (1) ◽

pp. 1-70 ◽

Cited By ~ 24

Author(s):

S Perin ◽

D RS Lean

Keyword(s):

Climate Change ◽

Uv Radiation ◽

Climate Warming ◽

Ozone Depletion ◽

Aquatic Ecosystems ◽

Stratospheric Ozone ◽

Aquatic Organisms ◽

Ultraviolet B ◽

The Arctic ◽

Uvb Radiation

Depletion of stratospheric ozone, the principal atmospheric attenuator of ultraviolet-B (UVB) radiation, by man-made chemicals has raised scientific and public concern regarding the biological effects of increased UVB radiation on Earth. There is an increased awareness that existing levels of solar UV radiation have an important influence on biological and chemical processes in aquatic ecosystems. For aquatic organisms, numerous studies have shown direct detrimental effects of UVB radiation at each trophic level. Fortunately, many aquatic organisms also possess a range of photoprotective mechanisms against UV radiation toxicity. In addition to its direct impact, harmful effects of UVB radiation at a single-trophic level can cascade through the food web and indirectly affect organisms from other trophic levels. Because UV radiation photochemically reacts with humic substances and other photosensitive agents in the water, increases in solar UVB can also indirectly affect aquatic organisms through the production and (or) release of different photoproducts like biologically available nutrients and harmful reactive oxygen species. Polar aquatic ecosystems have been of particular concern, since stratospheric ozone-related UVB increases have been the greatest in these regions. With the influences of climate warming and the possibility of future volcanic eruptions, ozone losses are expected to get worse in the Arctic stratosphere, and the ozone layer recovery may not follow the slow decline of industrial ozone-depleting compounds in the atmosphere. Climate warming is also expected to bring important changes in underwater ultraviolet radiation (UVR) penetration in Arctic freshwaters that would be more significant to the aquatic biota than stratospheric ozone depletion.Key words: Arctic, UV radiation, UVB, ozone depletion, climate change, aquatic ecosystems.

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Methanotrophic diversity in high arctic wetlands on the islands of Svalbard (Norway) - denaturing gradient gel electrophoresis analysis of soil DNA and enrichment cultures

Canadian Journal of Microbiology ◽

10.1139/w03-080 ◽

2003 ◽

Vol 49 (10) ◽

pp. 602-612 ◽

Cited By ~ 47

Author(s):

Ingvild Wartiainen ◽

Anne Grethe Hestnes ◽

Mette M Svenning

Keyword(s):

Methane Emission ◽

Gel Electrophoresis ◽

Denaturing Gradient Gel Electrophoresis ◽

The Arctic ◽

Rrna Gene ◽

Climatic Warming ◽

Soil Dna ◽

Enrichment Cultures ◽

Arctic Soil ◽

Gradient Gel Electrophoresis

The methanotrophic community in arctic soil from the islands of Svalbard, Norway (78°N) was analysed by combining group-specific PCR with PCR of the highly variable V3 region of the 16S rRNA gene and then by denaturing gradient gel electrophoresis (DGGE). Selected bands were sequenced for identification. The analyses were performed with DNA extracted directly from soil and from enrichment cultures at 10 and 20 °C. The two genera Methylobacter and Methylosinus were found in all localities studied. The DGGE band patterns were simple, and DNA fragments with single base differences were separated. The arctic tundra is a potential source of extensive methane emission due to climatic warming because of its large reservoirs of stored organic carbon. Higher temperatures due to climatic warming can cause increased methane production, and the abundance and activity of methane-oxidizing bacteria in the arctic soil may be important regulators for methane emission to the atmosphere.Key words: methanotrophic diversity, Svalbard, arctic wetland, denaturing gradient gel electrophoresis.

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