International Research Laboratory for Arctic Seas Carbon

The laboratory was established with funding of the Ministry of Education and Science of the Russian Federation in the framework of the project -The Siberian Arctic Shelf as a Source of Greenhouse Gases of Planetary Significance: Quantitative Assessment of Flows and Identification of Possible Environmental and Climatic Consequences The research is conducted under the supervision of Professor Igor Semiletov. The project main goal is to identify characteristic features and estimate the extent of spatiotemporal variability of the basic components of the carbon cycle on the Siberian Arctic shelf under conditions of warming and degradation of the permafrost. The particular attention is paid to the widest and shallowest shelf of the World Ocean, that is the Eastern Arctic seas (EAS), as a source of the greenhouse gases of global significance.

• Quantitative assessment of degradation rate of the permafrost in context of creating a model for transformation of methane potential and release of methane into the water column and the atmosphere for various scenarios of climate change.

The laboratory conducts research in two main areas:

1. The development and expansion of comprehensive studies focused on clarifying the role of underwater permafrost, possible destabilization of hydrates, upward flow of gas from deep geological sources. That is processes, determining the amount of methane emission from sediments into water and atmosphere. It is this aspect that crucially important for the understanding of formation mechanism of the atmospheric maximum of CH4 over the Arctic in the Holocene, i.e. the present time, and in the previous warm geological epochs.
2. The laboratory studies and identifies the core processes, responsible for developing a pool of ancient organic matter (OM) ground origin in the modern bottom sediments. They can lead to disbalance between the main components of the carbon cycle on the Arctic shelf due to oxidation of surface OM to CO2, thereby causing intensification of the greenhouse effect.

The main research results:

Based on comprehensive biogeochemical, geophysical, and geological studies we carried out quantitative assessment of the bubble methane flow on the shelf of the Eastern Arctic seas (MBA).  It was found out that depending on the state of underwater permafrost (the data obtained from core drilling, geophysical studies, and an improved mathematical model) the flow can be broken into 5 types from mg to hundreds of grams per square meter per day (Shakhova, Semiletov et al., Phil. Trans. R. Soc., 2015).

• Based on more than 200,000,000 precision measurements of the atmospheric methane concentration and more than 14,000 measurements of dissolved methane concentration, we found out abnormally high concentrations of methane in EAS. It is worth noting, that the highest values of atmospheric methane were found in areas of massive emissions of bubble methane, where it was up to 3.5-8.0 ppm, i.e. it is many times higher than the average concentration on the earth.

• We have proved, that the main factors, determining the significant supersaturation of the EAS waters with carbon dioxide and extreme abstraction of the EAS waters, are: 1) the growing influence of river runoff and degradation of permafrost, which is manifested in increase of erosive ground organic matter, which is mineralized on the shelf, thereby increasing the concentration of carbon dioxide in seawater (Semiletov et al., Nature Geoscience, 2016); 2) the increase in the temperature of surface water upon the reduction in the ice extent of the Arctic seas.
• For the first time, we have identified volatility of exports of terrestrial organic matter of various genesis over the past 9500 years. It was found out, that the export of erosional carbon has dominated all the time. This signal is more significant in the East Siberian Sea, comparing with the Laptev Sea. On the other side, in the Laptev Sea, the soil light organic matter has made a more tangible contribution. It was shown, that the maximum export rate of erosional carbon is typical for the last 1700 years and for the time period 9,500-9,300 and 8,500-8,300 years ago. These results expand the boundaries of fundamental studies, aimed at identifying and assessing of processes, determining export and transformation of ground organic matter of the present time, which were summarized in an author's monograph (Semiletov et al., 2017).

The core academic papers, that reflects the laboratory research achievements:

• Semiletov I., Pipko I., Gustafsson O., Anderson L.G., Sergienko V., Pugach S., Dudarev O., Charkin A., Gukov A., Broder L., Andersson A., Spivak E., Shakhova N. Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon // Nature Geoscience, 2016, vol. 9, 361-365, doi: 10.1038/NGEO2695.
• Sapart, C. J., Shakhova, N., Semiletov, I., Jansen, J., Szidat, S., Kosmach, D., Dudarev, O., van der Veen, C., Egger, M., Sergienko, V.; Salyuk, A., Tumskoy, V., Tison, J.L., Rockmann, T. The origin of methane in the East Siberian Arctic Shelf unraveled with triple isotope analysis // Biogeosciences, 14, 9, 2283-2292, 2017.
• Shakhova N., Semiletov I., Sergienko V., Lobkovsky L., Yusupov V., Salyuk A., Salomatin A., Chernykh D., Kosmach D., Panteleev G., Nicolsky D., Samarkin V., Joye S., Charkin A., Dudarev O., Meluzov A. and Gustafsson O. The East Siberian Arctic Shelf: towards further assessment of permafrost-related methane fluxes and role of sea ice // Phil. Trans. R. Soc. A, 2015, 373: 20140451. (Philosophical Transactions of the Royal Society A). 
• Semiletov I.P., Dudarev O.V., Pipko I.I., Pugach S.P., Sergienko V.I., Chubik P.S., Mazurov A.K., Shakhova N.E. The carbon cycle in the seas of the Eastern Arctic at the turn of the XX-th and XXI-st centuries.  Book 1. Transportation and Transformation of Carbon in the System - Land-Shelf/Tomsk Polytechnic University publishing house, 2017. – 545 p.
• Dudarev O.V., Charkin A.N., Shakhov N.E., Mazurova A.K., Semiletov I.P. The Modern Lithomorphogenesis on the East Arctic shelf of Russia. - Tomsk: Tomsk Polytechnic University publishing house, 2016. – 192 p.