Arctic Seas: projects/activities

The aims of the project are: - to evaluate the fluxes of radionuclides in the water column and their accumulation in the sediment, on a short-time scale; - to determine the C/N and delta13C-delta15N ratios in suspended and sedimentary matter, and test their use as tracers of origin, composition and transformation pathways of organic particles. The selected study area is the Kongsfjord-Krossfjord system, Svalbard, considered as representative test-site for studying processes occurring in Arctic fjords. The focus of the project will be on the processes occurring at the glacier-sea interface, where enhanced lithogenic and biogenic particle fluxes are reported in summer. Specific methods will be used to trace the particle sources. The rate of accumulation-resuspension processes will also be investigated from the inner fjord to the outer continental shelf.

The succession of macro- and microalgal communities in the Antarctic will be investigated in field experiments under various UV radiation (UVR) conditions and in the absence or presence of grazers. The observed differences in the succession process will be correlated to physiological traits of single species, especially in spores and germlings, which are the most vulnerable stages in their life histories. Photosynthetic activity of the different developmental stages will be measured routinely. Additionally we plan the determination of pigment composition, C:N ratios, content of UV protective pigments and of possible DNA damage. The experiments will start in spring, concomitant to the time of highest UVBR, due to the seasonal depletion of the ozone layer in the Antarctic region. Supplemental laboratory experiments will be conducted to determine the effects of UVR on spores and germlings of individual species. In addition to the above analyses, we plan to examine of UVR induced damage of cell fine structure and of the cytoskeleton. The results of both the field and laboratory experiments will allow us to predict the consequences of enhanced UVR for the diversity and stability of the algal community.

Radioactivity in the Arctic environment is a central topic within environmental pollution issues. Increased discharges of technetium-99 (99Tc) from the nuclear fuel reprocessing plant Sellafield to the Irish Sea has caused public concerns in Norway. This project (acronym “RADNOR”) includes model and monitoring assessments and improvements, assessment of current and novel abiotic and biotic dose parameters and dose calculations and use of realistic climatic background scenarios in order to assess corresponding consequences for transport of radioactive pollutants. RADNOR consists of three main components: part 1, the determination of levels and time series of 99Tc in benthic and pelagic food webs; part 2, containing working packages on improvements to the understanding of site-specific and time-dependent sediment-water interactions (KD), kinetics of accumulation (CF) and body distribution in marine organisms, including contaminated products for the alginate industry and part 3, dealing with model hindcasts and observations for spreading of 99Tc from the Sellafield nuclear reprocessing plant during the 1990s and improvement of the NRPA dose assessment box model. From the model outputs, doses to man and environment will be calculated resulting in a valuable database for use within environmental management and for decision makers.

The Submarine Operational And Research Environmental Database (SOARED)is comprised of a fixed relational environmental database using unclassified data collected during the Science Ice Exercises (SCICEX) during the past several years. It also includes publicly accessible gridded historical sound velocity, temperature and salinity data from 1900 from the US National Oceanographic Data Center. This project is a demonstration system to show ways to retrieve and analyze sound velocity, temperature and salinity profiles, bathymetry and ice thickness data using a mouse-driven GIS-based query.

Biological materials obtained in the central Arctic Ocean at the FSU “North Pole stations” in 1975-1981 have shown that the multi-year ice and ice/water interface is of rich and diverse biotop inhabited by the large number of diatoms and invertebrate animals. Two main matter fluxes in the sea ice ecosystem may be distinguished: (1) the inflow of biogenous elements from water into the ice interior where they are assimilated by the microflora during photosynthesis (summer stage), and (2) the outflow – from ice to water - of the organic matter accumulated in the summer due to photosynthesis (winter stage). Accumulation of organic matter within the sea ice interior during the process of photosynthesis may be considered as an energy depot for organisms of the whole trophic network of the arctic sea ice ecosystem. Recent data from the SHEBA Ice Camp drifted within the Beaufort Gyre 1997-1998 have shown that: (1) sea ice diatoms are very scarce by species and numbers; (2) fresh water green algae are dominated by numbers and distributed within the whole sea ice thickness; (3) invertebrate animals within the sea ice interior are not indicated; (4) invertebrate animals from the ice/water interface are scarce by species and numbers; (5) concentrations of chlorophyll and nutrients in the sea ice are significantly lower of the average concentrations measured before in this region for the same period of time. Remarkable accumulation of the organic mater within the sea ice interior were not indicated.

Ecology of bacterioplankton and bacterioneuston in the polar seas, distribution, number, in situ heterotrophic activity, involvement in natural purification processes from oil pollution.

The overall objective of MAIA is to develop an inexpensive, reliable system based on coastal sea-level data for monitoring the inflows of Atlantic Water to the northern seas. Available observation systems, including stan-dard tidal stations, will be used to obtain transport estimates with a time resolution of less than a week and show that the method is generic and can be applied to a similar monitoring of other regions.

Our broad area of enquiry is the role of polar regions in the global energy and water cycles, and the atmospheric, oceanic and sea ice processes that determine that role. The primary importance of our investigation is to show how these polar processes relate to global climate.