The Barents Sea is a shelf sea of the Arctic Ocean. Being a transition area between the North Atlantic and the Arctic Basin, it plays a key role in water exchange between them. Atlantic waters enter the Arctic Basin through the Barents Sea and the Fram Strait (Figure 3.1.1). Variations in volume flux, temperature and salinity of Atlantic waters affect hydrographic conditions in both the Barents Sea and the Arctic Ocean and are related to large-scale atmospheric pressure systems.

The Barents Sea is a shelf sea of the Arctic Ocean. Being a transition area between the North Atlantic and the Arctic Basin, it plays a key role in water exchange between them. Atlantic waters enter the Arctic Basin through the Barents Sea and the Fram Strait (Figure 3.1.1). Variations in volume flux, temperature and salinity of Atlantic waters affect hydrographic conditions in both the Barents Sea and the Arctic Ocean and are related to large-scale atmospheric pressure systems.

During 2013, the NAO index changed from negative values in January–March to slightly positive values which lasted the rest of the year. During winter (2012 –2013) northerly, northwesterly and northeasterly winds prevailed over the Barents Sea; during summer (April–August) southerly, southwesterly, and southeasterly winds prevailed. During autumn (September–October) wind direction shifted to easterly and northeasterly.

Air temperature data from the NOMADS (NOAA Operational Model Archive Distribution System http://nomad2.ncep.noaa.gov) website were averaged over the western (70–76°N, 15–35°E) and eastern (69–77°N, 35–55°E) Barents Sea. During 2012, positive air temperature anomalies prevailed in the Barents Sea, with the largest values (4–7°C) in the eastern part of the sea from January to April (Figure 4.2.2).

Volume flux in the Barents Sea varies within periods of several years, and was significantly lower during 1997–2002 than during 2003–2006 (Figure 4.2.3). During winter 2006, volume flux was at a maximum throuhout 1997-2013; whereas, during fall volume flux was anomalously low. After 2006, volume flux has been relatively low, particularly during spring and summer. During 2013, volume flux was generally larger than the 1997–2013 average.

Throughout 2013, positive surface water temperature anomalies prevailed in the Barents Sea. The largest anomalies (up to 4.0°C) were found in the eastern sea. Compared to 2012, the surface temperatures were much higher (by 1.3–2.7°C) in most of the Barents Sea, especially in its central and southern parts. In August–September 2013, during the joint Norwegian-Russian ecosystem survey, the surface temperatures were the highest since 1951 in about 50% of the surveyed area (ICES AFWG, 2014).

Mesozooplankton biomasses

Mesozooplankton play a key role in the Barents Sea ecosystem by transferring energy from primary producers to animals higher in the food web. Geographic distribution patterns of total mesozooplankton biomass show similarities over time, although some inter-annual variability is apparent. Challenges in covering the same area each year are inherent in such large-scale monitoring programs, and inter-annual variation in ice-cover is one of several reasons for this. This implies that estimates of average zooplankton biomasses for different years might not be directly comparable.

Benthos

Benthos is an essential component of the marine ecosystems. It can be stable in time, characterizing the local situation, and is useful to explain ecosystem dynamics in retrospect. It is also dynamic and shows pulses of new species distribution, such as the snow crab and the king crab, and changes in migrating benthic species (predatory and scavenger species such as sea stars, amphipods and snails with or without sea anemones). The changes in community structure and composition reflect natural and anthropogenic factors. There are more than 3000 species

Total biomass

Zero group fish are important consumers on plankton and are prey of other predators, and, therefore, are important for transfer of energy between trophic levels in the ecosystem. Estimated total biomass of 0-group fish species (cod, haddock, herring, capelin, polar cod, and redfish) was 1.92 million tonnes during August-September 2017; slightly above the long term mean of 1.76 million tonnes (Fig 3.5.1). Biomass was dominated by cod and haddock, and mostly distributed in central and northern-central parts of the Barents Sea.

Most Barents Sea fish species are demersal (Dolgov et al., 2011); this fish community consists of about 70-90 regularly occurring species which have been classified into zoogeographical groups. About 25% are Arctic or mainly Arctic species. The commercial species are all boreal or mainly boreal (Andriashev and Chernova, 1995), except for Greenland halibut (Reinhardtius hippoglossoides) that is classified as either Arcto-boreal (Mecklenburg et al., 2013) or mainly Arctic (Andriashev and Chernova, 1995).

Phytoplankton development in the Barents Sea is typical for a high latitude region with pronounced maximum biomass and productivity during spring. During winter and early spring (January-March), both phytoplankton biomass and productivity are relatively low. Spring bloom is initiated during mid-April to mid-May and may vary strongly from year to year. Bloom duration is typically about 3-4 weeks and is followed by a reduction in phytoplankton biomass mainly due to nutrient exhaustion and grazing by zooplankton. Later in the fall when the increasing winds start to mix the upper layer and bring nutrients to the surface, a short autumn bloom can be observed. However, the timing of phytoplankton development can vary geographically. Spring bloom in the Atlantic water domain (without sea-ice) is thermocline-driven; whereas in the Arctic domain (with seasonal sea-ice), stability from ice-melt determines the bloom (Skjoldal and Rey 1989, Hunt et al. 2012). Thus, spring bloom at the ice edge can sometimes take place earlier than in the southern regions of the Barents Sea due to early stratification from ice melting.

There were no special researchers on marine mammals on board of Norwegian vessels during ecosystem survey. However, the Norwegian observers of seabirds on boards «Eros», «Johan Hjort», and «Helmer Hansen», as far as possible in parallel also did observations of marine mammals.

8 species of marine mammals were observed during the observation period in the research area, reaching a total of 899 individuals.

Mercury is the single most toxic element for seabirds. Mercury, along with Cadmium and lead, is one of the heavy metals that are of environmental concern as it can be toxic at levels only moderately elevated above natural ambient levels.

The surface sediments, i.e. the predominant sediment type of the upper ~ 50 cm of the seabed, form the uppermost part of a sediment sequence covering the rocks of the Barents Sea. This sediment sequence varying in thickness from a few to several hundred meters and was mainly deposited during the Quaternary (the last 2.6 million years), a time period where glaciations took place repeatedly.

The map service shows the grain size of seabed surface sediments of the Barents Sea. The map has been compiled in cooperation between the Geological Survey of Norway, Trondheim (Aivo Lepland), and OAO "SEVMORGEO", St. Petersburg (Aleksandr Rybalko), in the frame of the Norwegian-Russian Environmental Commission Workplan 2013-2014, OECEAN 5. Existing maps produced by various organizations served as a basis for the compilation.

This biotope map, covering the entire Barents Sea, has been compiled in collaboration between the Geological Survey of Norway, the Norwegian Institute of Marine Research (IMR) and the Russian Polar Research Institute of Marine Fisheries and Oceanography (PINRO) in the frame of the Norwegian-Russian Environmental Commission Workplan for 2011-2013 and 2013-2015.

The protected areas in Northwest Russia are divided into different categories of protection and management. In strict nature reserves (zapovednik) no economic activities are permitted. National parks are designated to nature conservation, research, educational and cultural purposes as well as controlled recreational activities. In national parks there are restrictions to the management of natural resources. Nature parks (prirodnyi park) are the equivalent of the Norwegian

Scientists, managers and commercial fishermen from Northern Norway, Finland and north-west Russia, White Sea area combined their efforts in the Kolarctic salmon project (2011-2013), with the aim of providing a better knowledge-base for the countries salmon management. Within this joint and unique effort bio-specimen were sampled along the North-Norwegian coast and in Russian Barents and White Seas generating the most comprehensive ecological and genetic datasets for Atlantic salmon (Salmo salar).