The following research groups participate in the OSL Fellowship Program 2010.

1. Spatial and temporal variability of the Laptev Sea polynya region in 2007-2009: analysis and synthesis of biological data from the TRANSDRIFT XII-XVI expeditions
E. Abramova, F. Martynov, D. Taborskiy

2. Evaluation of the coupled permafrost-vegetation response to climate change: synthesis of observations and modeling
O. Anisimov, S. Reneva, V. Kokorev

3. Interannual variability of the Arctic Ocean surface layer in winter and its causes
E. Chernyavskaya

4. Hydrochemical characteristic of arctic lakes and polygons of the Lena River delta and characteristic their environmental sustainability for human impact and for changes of natural regime
A. Chetverova

5. Geochemical and palynological investigations of the 140 m long permafrost core from Lake Elgygytgyn Crater
G. Fedorov, E. Morozova, N. Ostanin

6. Tracking environmental change using invertebrate bioindicators from lakes of Northern Yakutia (Siberia, Russia). Step toward a regional bioindicators-climate transfer function
L. Frolova, L. Ushnitskaya, O. Tumanov

7. Dense water formation on the Laptev Sea shelf in the changing Arctic
V. Ivanov, V. Nikolaev, A. Il'ina

8. Millennial-scale variability of paleoenvironments on the Shirshov Ridge, Bering Sea, during the last climatic cycle
E. Ivanova, E. Ovsepyan

9. Gas seepage and possibilities for the shallow gas hydrate accumulation at the Barents and Kara seas
T. Matveeva, E. Logvina, D. Korshunov

10. Comparison of spring sea-ice algal and ice-edge phytoplankton communities from the Laptev Sea polynya, 2008 & 2009 years
Ye. Polyakova, N. Kopeiko

11. Experimental investigation of atmosphere-sea-ice interaction in Laptev sea
I. Repina, D. Chechin, N. Fomin

12. Holocene palaeoclimate of the Laptev Sea region from pollen signal changes in lake sediments along a transect from tundra to forest
L. Savelieva, P. Vakhrameeva, D. Titova

13. Assessment of permafrost melting rates and its influence on hydrological regime in Eastern Siberia using various scenarios of climate change
O. Semenova, N. Kotova, L. Lebedeva

14. Aeolian transport and fluxes of matter (including pollutants) in the Arctic
V. Shevchenko, N. Goryunova, D. Starodymova

15. Late Pleistocene and Holocene environmental changes in Eurasian Arctic seas inferred from microfossils and lithology: summary of recently obtained results
E. Taldenkova, A. Stepanova, Ya. Ovsepyan

16. Multiyear variations of sea ice thickness in the Laptev Sea by data derived in the annual „Sever" expedition during 1969-1993
A. Timofeeva


1. Spatial and temporal variability of the Laptev Sea polynya region in 2007-2009: analysis and synthesis of biological data from the TRANSDRIFT XII-XVI expeditions

E. Abramova, F. Martynov, D. Taborskiy

In our new project we focus on writing two papers about the current state of different ecosystem parameters and their seasonal variability on the Laptev Sea shelf and especially the polynya region. Biological data collected in summer and winter during the TRANSDRIFT XII-XVI expeditions will be used for the description of chlorophyll a, pelagic and benthic fauna and flora distribution, foodweb structure, invasion of open-water marine and riverine species, as well as overall and regional changes in productivity as affected by the changes in meteorological, oceanographic, hydrological, and hydrochemical boundary conditions during the last three years.

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2. Evaluation of the coupled permafrost-vegetation response to climate change: synthesis of observations and modeling

O. Anisimov, S. Reneva, V. Kokorev

The main project objective is to study the feedbacks between the climate-induced changes in permafrost and vegetation. We are going to collect and analyze published data on vegetation dynamics in Russian permafrost regions, compare it with climatic data and permafrost changes. We will use the results of such analysis to construct a coupled climate-vegetation-permafrost model. The model will be used with several climatic scenarios to construct consistent vegetation and permafrost projections for the northern Eurasian region. We will seek collaboration with the researcher group in Jena that is involved in developing the LPJ dynamical vegetation model in order to discuss the potential application of our model in their studies. In the coupled model we will account for a sufficiently large amount of plant functional types (PFT) in the tundra to identify the impacts of changing climate and permafrost on the northern biomes. All findings, data bases and models developed in the course of the project will be deposited on the dedicated web site http://www.permafrost.su.

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3. Interannual variability of the Arctic Ocean surface layer in winter and its causes

E. Chernyavskaya

The Arctic Ocean region is known to be very sensitive to environmental conditions. Its surface layer is the most dynamical and changeable part which occupies the depth from the ocean surface down to 10-40 m in summer and 25-100 m in winter. The bulk of freshwater, flowing into the Arctic Ocean and consisting of precipitation, continental runoff and waters which form in the ice melting, accumulates in the surface layer, which has a largest impact on thermohaline structure and the Arctic Ocean water circulation. The main goals of this project are to study the Arctic Ocean surface layer to estimate changes of surface layer parameters and the role of different factors in climatic variability of the Arctic Ocean surface layer.

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4. Hydrochemical characteristic of arctic lakes and polygons of the Lena River delta and characteristic their environmental sustainability for human impact and for changes of natural regime

A. Chetverova

This proposal is based on results obtained from expeditions to the Lena Delta by the Arctic and Antarctic Research Institute, St. Petersburg State University, and Alfred Wegener Institute, in carrying out the grants supported by the OSL in 2008-2009 and by the DFG in 2009. It is a continuation of water and sediment research in Lena River delta. And as a result it should become a basis for grantee's master thesis. The main project objective is to determine hydrochemical characteristics of water bodies (lakes, polygons and Olenekskaya channel water) of Samoylov Island, as well as their changes during the months, to define the conditions of hydrochemical composition formation and sources or biogenic elements. On the basis of the past projects results of grain-size and geochemical analyses of sediments were obtained. In July 2009 an international expedition to the Lena Delta took place, in which the grantee participated. Our own results and materials of studying, new samples and data from this expedition and laboratory results from the expedition 2008 are planned to be used for the applied research. Scientists from the AWI (Potsdam) and AARI have been working on scientific topics on similar water objects. Combining German meteorological, hydrological and biological data with SPbU measurements will allow conducting the investigation using a greater amount of observation data and with a higher level of confidence.

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5. Geochemical and palynological investigations of the 140 m long permafrost core from Lake Elgygytgyn Crater

G. Fedorov, E. Morozova, N. Ostanin

This proposal requests technical support for geochemical and palynological analysis of the upper part of the 141.5 m long permafrost core collected from Lake Elgygytgyn crater jointly with German colleagues in November-December 2008. This field campaign was a first phase of the international „Lake Elgygytgyn Deep Drilling" research project. Our research group will closely collaborate with the German group from the AWI-Potsdam. And our joint main goal is the reconstruction of the environmental conditions of the permafrost development in the Elgygytgyn Lake crater area.

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6. Tracking environmental change using invertebrate bioindicators from lakes of Northern Yakutia (Siberia, Russia). Step toward a regional bioindicators-climate transfer function

L. Frolova, L. Ushnitskaya, O. Tumanov

Cladocera and chironomids fossil assemblages in lacustrine sediments are increasingly important for reconstructing past ecological and climate change, as these organisms are diverse, sensitive to limnological and climatic conditions and represent different compartments of lake ecosystems. Furthermore, the remains of these organisms preserve well in lake sediments, are identifiable and they are therefore valuable indicators of past environmental change. The purposes of this research will be to examine Cladocera and Chironomidae assembles (contemporary and sub-fossil) from 68 northern Siberian lakes (Anabar district and Kolyma region), and determine how invertebrates are distributed within the region with regard to environmental gradients. To obtain empirical models (i.e. transfer functions), a calibration dataset is needed which consists of the water chemistry data, climatological data and the species assemblage distributions from about 50 to 100 lakes. Since the transfer function estimates a single variable of the physico-chemical characteristics measured in the calibration dataset, it is important to allow for a sampling intensity and frequency appropriate for obtaining reliable estimates of the variable to be reconstructed. Our study is directed towards developing an empirical model based on the relationships between Chironomids and Cladocera taxa and abiotic variables (e.g., water chemistry, climate variables, etc.), particularly in terms of species optima to a measured variable. This inference model can then be used to reconstruct past changes of the abiotic variable of interest.

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7. Dense water formation on the Laptev Sea shelf in the changing Arctic

V. Ivanov, V. Nikolaev, A. Il'ina

Dense waters forming on the Arctic continental shelves and descending along continental slope (i.e. cascading) are believed to be a significant contribution, hitherto not accurately quantified, in shaping of intermediate and deep Arctic waters. Dense water originates on specific Arctic shelves in winter through freezing and consequent brine ejection. The northwestern Laptev Sea shelf is one of the regions, where this process was documented. Formation of dense water in the Laptev Sea was addressed in the past on the basis of historical observations and modeling. Proposed study will provide useful benchmark information on how currently observed decrease of the Arctic ice cover may effect dense water production on the Arctic shelves and therefore, climatically important related processes, such as water mass transformation in the deep Arctic Ocean and global thermohaline circulation. The project goal is to simulate dense water formation on the northwestern Laptev Sea shelf and transport of this water down continental slope using newly obtained hydrographic data and advanced mathematical modeling. The outcome of this project will add to understanding of mechanisms controlling shelf-basin water exchange in the Arctic Ocean in the present climate, which is characterized by substantial retreat of the ice cover in summer.

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8. Millennial-scale variability of paleoenvironments on the Shirshov Ridge, Bering Sea, during the last climatic cycle

E. Ivanova, E. Ovsepyan

High-resolution multi-proxy study of the 18m-long piston core SO201-2-85KL by our team in cooperation with German partners will provide a pilot reconstruction of poorly investigated paleoenvironments of the western Bering Sea during the last glacial-interglacial cycle. The core was retrieved from the Shirshov Ridge during the Russian-German expedition onboard RV „Sonne" cruise 201 Leg 2 in September 2009. The major goal of the proposal is to evaluate changes in the surface water conditions, bioproductivity, North Pacific Intermediate Water production/ventilation and bottom current velocities by analyzing planktic and benthic foraminiferal assemblages, grain-size and trace metals distribution. As dropstones were not found in the sediment cores from the Shirshov Ridge, the question about the sea-ice conditions during the stadials has to be addressed. Besides, we are going to assess changes in trace element and siliclastic sediment sources. Use of the OSL equipment (especially CIROS ICP and SediGraph 5100) will ensure the modern level of grain-size and trace metals analyses. According to onboad logging, the average sedimentation rate in the core is about 10-12 cm/1000 yr, therefore we expect to get insights into the millennial-scale climatic variability. Furthermore, we intend to correlate paleoceanographic changes in the Bering Sea, surrounding lands and remote regions.

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9. Gas seepage and possibilities for the shallow gas hydrate accumulation at the Barents and Kara seas

T. Matveeva, E. Logvina, D. Korshunov

Emission of methane as one of the greenhouse gases through the seafloor could influence the environment variability and control formation of the shallow gas hydrates. On the other hand, gas hydrates are a component of the ecosystem very sensitive to climate changes and human activity. The main idea of this study was to forecast potential areas of the shallow gas hydrate accumulation related to hydrocarbon gas seepage in the Barents and Kara seas off Russia. The proposed project is going to map potential gas seepage-sites and forecast related hydrate occurrences from existing marine geophysical and geological data. The study will base on the interpretation of high-resolution seismic data from long-term Russian surveys, examination of bottom water characteristic measurements and overall hydrocabon content in sediment. Existing pressure-temperature conditions will be calculated using the CSMHYD Hydrate Program software in order to predict areas favorable for the seepage-related gas hydrate formation. As the result we will be able to forecast hydrate occurrences related to shallow gas seepage in the Barents and Kara seas. The proposed study is important today in the context of global climate changes impacting the environment of the Eurasian North including submarine and land permafrost.

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10. Comparison of spring sea-ice algal and ice-edge phytoplankton communities from the Laptev Sea polynya, 2008 & 2009 years

Ye. Polyakova, N. Kopeiko

The proposed researches are planned as continuation of the studies which we carried out in the frame of the OSL granted project (2009) "Spring sea-ice algal and ice-edge phytoplankton communities from the Laptev Sea polynya in April 2008". The Laptev Sea polynya is a major area of sea-ice production for the Arctic Ocean, and it is one of the key elements of the environmental system of the Laptev Sea because of the high level of biological activity in this region during the spring and early summer time. The retreat of sea-ice in the Arctic during the last decades requests multidisciplinary investigations of this area. The main goals of our proposed researches are: 1) to complete the study of microalgae (diatoms, dinoflagellates, chrysophytes, chlorophytes) in sea-ice and phytoplankton samples, obtained during the TRANSDIFT XIII (April 2008) expedition to the Laptev Sea polynya area, their species composition, biomass and abundances; 2) to carry out investigation of abundances, biomass, and species composition of phytoplankton and sea-ice communities in the selective samples, obtained during the spring 2009 (TRANSDRIFT XV); 3) to prepare and submit for publication the article: Ye.I. Polyakova, L. Astakhova, T.S. Klyuvitkina, E.N. Abramova, H. Kassens, J. Hoelemann: "Composition and distribution of the sea-ice and ice-edge phytoplankton assemblages in the Laptev Sea during the spring 2008".

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11. Experimental investigation of atmosphere-sea-ice interaction in Laptev sea

I. Repina, D. Chechin, N. Fomin

The problems of climatology attract considerable attention because the climate-related processes occurring in the Arctic regions are specific and it is necessary to clarify the role of the Arctic in the mechanism of shaping climate and weather. The mechanism of energy exchange between the atmosphere and the underlying surface in the Arctic Ocean is very complicated. On one hand, the ice cover hinders the heat exchange between the atmosphere and the ocean while on the other hand the presence and development of the ice cover is determined by the intensity of thermal and dynamic atmosphere-ocean interactions. The ice cover determines albedo changes and energy exchange. Our experimental work is focused on studying the effects of structural and thermal non-uniformity at the ice covered surface on heat and momentum exchange between atmosphere and underlaying surface in the Laptev Sea since 2004. Of special interest is the effect of polynyas and leads on the heat balance of the Laptev Sea. The outcome of this project will be advanced parameterization of turbulent energy exchange for climate models.

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12. Holocene palaeoclimate of the Laptev Sea region from pollen signal changes in lake sediments along a transect from tundra to forest

L. Savelieva, P. Vakhrameeva, D. Titova

Vegetation changes reflected in fossil pollen spectra are a primary source of information about climatic fluctuation in the past. Pollen data is widely used in palaegeographical reconstructions. However, there is no clear criterium for the palaeoclimate signal on the basis of pollen data especially for the Arctic region where open landscapes dominate. This is connected to the abundance of long-distance pollen in spore-pollen spectra from tundra zone. The palaeoclimate signal can be reflected in each vegetations zone differently. Therefore, it is necessary to conduct complex pollen studies of bottom lake sediment and surface-sediment samples in comparison with current vegetation. These results are the prelude for the interpretation of core records taken within different vegetation zones. For the first time, lakes were studied along a transect from tundra to forest in the Laptev Sea region during the Russian-German LENA 2009 expedition. Bottom sediments from 11 lakes and surface samples were collected. Four cores of lake sediments with a thickness from 30 cm up to 120 cm were chosen for the proposed research. A comparison between the results of spore-pollen analysis of surface-sediment samples and surrounding vegetation will be performed. That complex approach allows carrying out more correct palaeogeographical reconstructions on the basis of pollen data. During the proposed project the conception about formation and changes of subfossil and fossil spore-pollen spectra and subfossil and fossil spore-pollen spectra and according them palaeoclimate signals an correlation with vegetation zones will be obtained.

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13. Assessment of permafrost melting rates and its influence on hydrological regime in Eastern Siberia using various scenarios of climate change

O. Semenova, N. Kotova, L. Lebedeva

Understanding the effect of climate change in the permafrost is critical to assessing its various impacts on ecology, infrastructure, etc. The deterministic-stochastic approach can be used for effective quantifiable probabilistic evaluation of the effects of climate change on permafrost and runoff regimes. Here the deterministic models distinguish between the processes in permafrost landscapes with different soil, vegetation, and snow properties, while the stochastic models provide stochastic meteorological input and a framework to link global climate models in a changing environment with the land surface components. The goal of the project is to assess the possible changes in permafrost properties (active layer depth, temperature, seasonal variations) of different landscapes of Eastern Siberia on the basis of deterministic-stochastic modelling using IPCC climate change scenarios. Particular emphasis will be given to the determination of the change of the annual, seasonal and extreme runoff distribution from a probabilistic point of view, and to the movement on the northern limit of the permafrost at different depths for each of the scenarios (including that of the German Max Planck Institute for Meteorology). The research team will stay in scientific contact with the Dr. Julia Boike (AWI) group of young investigators. The project will continue the research started during the project OSL-09-20 "Estimation of water and energy balance model parameters for permafrost conditions using observational data of experimental sites in Eastern Siberia". It will be conducted by three young scientists, one who recently completed PhD and two students.

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14. Aeolian transport and fluxes of matter (including pollutants) in the Arctic

V. Shevchenko, N. Goryunova, D. Starodymova

We plan to study the aeolian transport and fluxes of chemical elements and compounds (including pollutants) in the Arctic Ocean and surrounding land. We would like to estimate changes in delivery and accumulation of different types of particulate matter. Multidisciplinary approach and 4-dimension studies are necessary. Our work will be focused on samples from the Eurasian Arctic seas and their catchment areas, Central Arctic Ocean, Amundsen Gulf (Canadian Arctic), and Spitsbergen. We plan to study the composition of aerosols, snow, particulate matter, sedimentary matter from sediment traps from the Arctic Ocean, lake sediment and peat cores from the White and Barents seas catchment area. We will compare our results of the Eurasian Arctic studies with our new analyses and literature data from the other Arctic regions. This project could link PACES, ICARP II, SEDIBUD, OASIS, NABOS, Circumpolar Flaw Lead (CFL) and "Laptev Sea System" with active Russian-German cooperation.

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15. Late Pleistocene and Holocene environmental changes in Eurasian Arctic seas inferred from microfossils and lithology: summary of recently obtained results

E. Taldenkova, A. Stepanova, Ya. Ovsepyan

The project is aimed at summarizing the recently obtained new data on the postglacial environmental evolution of the Laptev Sea region and accomplishment of the ongoing investigation of the early stage of the penultimate interglacial in the Western Eurasian Arctic. Three papers will be submitted to the International Journals: 1) A. Stepanova, E. Taldenkova, H.A. Bauch: Ostracod paleoecology and reconstruction of environmental changes in the Laptev and Kara seas during the postglacial transgression (to be submitted to Marine Micropaleontology); 2) E. Taldenkova, S. Nikolaev, H.A. Bauch, J. Gottschalk, J. Rostovtseva: Variability in sea-ice cover extent and iceberg-rafting in the western Laptev Sea during the last 17.6 cal.kyrs BP (to be submitted to Quaternary Science Reviews); 3) E. Taldenkova, H.A. Bauch, A. Stepanova, I. Pogodina, Ya. Ovsepyan, E. Kandiano: Microfossil evidence for environmental changes and Atlantic-derived water masses inflows to the western Laptev Sea continental margin during the Postglacial and Holocene (to be submitted to Polar Research). The ongoing high-resolution investigation of microfossils and lithology of marine sediments from Bychye section (NE White Sea) will be completed, and the draft of a paper will be prepared dealing with the description of the regional past environmental changes during the late Saalian-early Eemian transition.

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16. Multiyear variations of sea ice thickness in the Laptev Sea by data derived in the annual „Sever" expedition during 1969-1993

A. Timofeeva

The extent of Arctic sea ice has declined in recent decades. Variations of sea ice thickness are sensitive indicators of climate change. Different sources of data are used for these investigations. However, the period of instrumental observation is much too short to determine any significant ice thickness trend. The Laptev Sea represents a significant source area of sea ice. Changes of ice thickness in the Laptev Sea are of importance for the sea ice budget and ocean-ice processes in the whole Arctic. In the frame of the Soviet-Russian expedition "Sever," ice thickness measurements by drilling were executed regularly starting in 1948. Annual data with a big amount of working points in the Laptev Sea were collected beginning in 1969. The major purpose of the applied project is an estimation of multiyear sea ice thickness variability in the Laptev Sea by data derived in the expedition "Sever" for the period 1969-1993. Finding a possible correlation with atmospheric circulation is of great importance. Data of "Sever" expeditions are not digitized and should be retrieved from paper and prepared for digital usage. During the project, data will be processed using capabilities of spatial analysis of ArcGIS, Surfer, etc.

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