ESSAS - Ecosystem Studies of Subarctic and Arctic Seas

ESSAS Project Endorsements

Research and public dataset production on the Arctic marine environment

Knowledge regarding ocean heat transport, marine ecosystem, and biogeochemical cycles in the Arctic central basins and marginal ice zones is still insufficient, and studying these topics is a pressing task in order to achieve sustainable utilization of the rapidly changing polar region. In this research program, we aim to clarify the Arctic marine environment, following three sub-programs:

  1. Ocean Heat/Freshwater Transport and Biogeochemical Cycles
  2. in Seasonal and Multi-Year Sea-Ice Zones
  3. Vulnerability and Resilience of Marine Ecosystem
  4. in Response to Rapid Sea-Ice Retreat
  5. Air–Sea (Including Waves) Interactions Related to Sea Ice

Each of the team members participates in multiple sub-programs, and we will aim to create an overall picture of the Arctic marine environment by exchanging information with related other groups. Our efforts with advanced observation systems to approach the marginal and multi-year ice zones – which despite being important areas had thus far been difficult to access – represent a major progression from the previous Japanese Arctic research projects such as GRENE-Arctic and ArCS. As one means to provide valuable findings related with human society, we will release public datasets on the Arctic marine environment.

The findings of sub-programs 1 and 2 will contribute to the preservation and sustainable use of fish stocks controlled by the Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean, as well as ecosystem-based management of marine food sources. Knowledge based on surveys in marginal ice zones and ice camp stations in sub-program 3 will be utilized to achieve more accurate prediction of sea conditions for safe and efficient navigation along the Arctic Sea Route.

Assessing risks of cumulative impacts on the Barents Sea ecosystem and its services (BarentsRISK)

BarentsRISK is the first unifying framework for risk assessment of multiple, interacting pressures related to climate warming, fisheries, petroleum, transportation and invasive species in the Barents Sea, also taking into account indirect, food web interactions. The project builds on the Ecological Risk Assessments (ERAs) framework and includes a structured approach to i) identifying the most critical present and emerging future pressures, with extensive stakeholder involvement across sectors and with natural and social scientists, ii) qualitative and quantitative approaches used in a hierarchical manner to assess current and future risks of cumulative impacts on ecosystem components, structure and functioning, including antagonistic and synergistic interaction effects, iii) efficiently and transparently communicate risks and associated uncertainties, and iv) determining how these ecological risks are linked to ecosystem services provided by the Barents Sea, and thus to societal aspects important for management and policy makers. Interaction between natural and social scientists and coproduction with stakeholders from management agencies and industry through the whole project is an essential part of Barents-Risk. Stakeholders are actively involved in all parts of the ERA, through workshops and one-to-one interaction with our scientists.

AnalogueART (Natural Analogues of an Arctic in Rapid Transition)

Our current understanding of key processes driving the responses of Arctic species and ecosystems to climate change is limited since the majority of studies conducted so far have been in vitro, short-term, rapid perturbation experiments on isolated elements of the ecosystem. It is difficult to extrapolate from such studies to larger scales, as these are generally too short-term to reveal how organisms may adapt/acclimatize. Experiments have often been performed with set constant pCO2 levels (which are unrealistic) and use organisms that are separated from their natural suite of competitors, predators, parasites and facilitators. In reality, OA itself is a multi-stressor dependent on a number of drivers (e.g., pCO2, salinity, total alkalinity, temperature) that form a mosaic of natural temporal and spatial gradients, particularly in coastal areas (e.g., Arctic fjords). Temporal and spatial gradients with regard to OA variability will be investigated in other parts of the FRAM OA flagship. Consequently, this project will link to past and present flagship activities by investigating how these natural temporal and spatial gradients in multiple OA drivers (pCO2, salinity and temperature) affect the physiological and skeletal responses of key benthic and planktonic species. Experiments will be performed within naturally assembled systems, where organisms have been exposed to a natural suite of energetic modulators and stressors, possibly across multiple generations of selection. Benthic invertebrates (bivalves, urchins and amphipods) and zooplankton (Limacina helicina) will be collected from across carbonate chemistry gradients previously identified in Kongsfjorden and Rijpfjorden.

VITALS (Ventilation, Interactions and Transports Across the Labrador Sea)

The objective of VITALS is to understand and model the functioning and vulnerability of the Labrador Sea as a key component of the earth’s climate system including its uptake of oxygen, anthropogenic carbon, and exchange of heat with the atmosphere. Measurements of oxygen, carbon dioxide and other climate-relevant gases will be taken over several seasonal cycles, their temporal and spatial variability in the Labrador Sea characterized, and the factors controlling their uptake, storage and circulation will be determined. The fluxes will be parameterized in terms of the forcing factors so that models have the appropriate physics and flexibility to simulate their evolution in a changing climate. The links between processes in the Labrador Sea and the global climate system will be outlined. The working hypothesis is that deep convection in the Labrador Sea, which allows for exchange of oxygen and natural and anthropogenic carbon to the deep ocean, is sensitive to the warming that is taking place at high latitudes. Validating and quantifying this sensitivity is central to the research as well as the broader community of climate change researchers and policy makers interested in characterizing, and possibly minimizing, the effects of global climate change. More details can be found at

Arctic Eis: Arctic Ecosystem integrated survey

The objective of Arctic Eis is to provide an unprecedented baseline for understanding Arctic marine and coastal fish and invertebrate communities and to assess the potential effects of future development and climate change on fisheries resources and the marine environment in the northern Bering and Chukchi Seas. Significant gaps currently exist in our understanding of these regions, particularly with regards to fish communities. Thus, our ecosystem-wide approach aims to provide the first integrated and geographically complete survey of the oceanography, plankton, fish and invertebrate communities of the northeastern Bering Sea shelf and eastern Chukchi Sea shelf. To address these objectives, we will use a combination of field and laboratory studies, modelling, retrospective analyses, and data syntheses. Field surveys will be conducted in 2012 and 2013 with data analysis and syntheses continuing through 2016. We further aim to build a cooperative research network with on-going projects and research efforts in the region to greatly enhance our overall understanding of these marine environments.

The measurable goals of this project are to:

  • Collect baseline fisheries and oceanographic data to enable resource managers to better predict effects of climate and human impacts on ocean productivity and on the ecology of marine and anadromous fish species within the northeastern Bering Sea and Chukchi Sea;
  • Assess the distribution, relative abundance, diet, energy density, size, and potential predators of juvenile salmon, other commercial fish, and forage fish within the northeastern Bering Sea and Chukchi Sea; and
  • Evaluate the effect of climate change on the health and status of pelagic fishes within the northeastern Bering Sea and Chukchi Sea.

Details on Arctic Eis can be found at

Ecosystem Studies of the Arctic Ocean with declining Sea ice (ECOARCS)

The recent decrease in Arctic sea ice has caused various changes in the Arctic climate and ecosystems. For example, melting of sea ice has improved the light environment for phytoplankton growth but at the same time it increased surface stratification thereby suppressing nutrient supply from deeper layers. Benthic organisms have also been threatened by changes in Arctic environments. Currently, they feed on the ice-edge bloom of phytoplankton that sinks to the seafloor but this may decrease or cease altogether in some areas. However, warming of the Arctic Ocean may increase the population of zooplankton and fish. Furthermore, reduction of sea ice also changes habitat distributions for species in the Arctic and Sub-Arctic seas. For better understanding changes in Arctic ecosystems, we are conducting multi-disciplinary studies examining not only biological but also physical and chemical aspects of the drastically changing Arctic environments. The ECOARCS research project was initiated in 2011 under the GRENE Arctic Climate Change Research Project in Japan ( It focuses on the Pacific side of the Arctic and Sub-Arctic seas, where various environmental changes have already accompanied the sea ice reduction. Hydrographic surveys by R/V Mirai (JAMSTEC), TS Oshoro Maru (Hokkaido University), and various ice-breakers under international collaboration are being carried out. In addition, we are conducting year-round mooring observations that provide hydrographic, chemical and biological data even in undersampled winter time. To clarify the feeding behaviour of higher trophic levels, we are also using bio-logging techniques and monitoring large areas of the Arctic Ocean via satellite throughout the year. Furthermore, we are developing marine ecosystem models for the Arctic Ocean that can diagnose in detail the ongoing changes in the Arctic marine ecosystem and will be used predict future ecosystem scenarios.

Norway-US Climate Change and Marine Ecosystems (NUCCME)

The NUCCME international scientific workshop was held in Ulvik, Norway, 6-9 May 2014 as part of the next round of bi-lateral ecosystem collaborative studies between Norway and the United States (see MENU projects below). The workshop was jointly undertaken with the Nordic network: Climate impact on fish, fishery industry and management in the Nordic Seas (CLIFFIMA). The main objectives of NUCCME/CLIFFIMA are to use future climate projections (1) to explore how they can be used in ecosystem models to determine the likely changes to the lower trophic levels, develop ecosystem indicators of such change, and identify related variables indicative of ecosystem productivity; (2) to examine models of living marine resources to explore how to include climate features in future projections and setting of harvest control rules; and (3) to determine the potential economic and societal consequences of climate change in the two regions. This network has been examining the effects of climate change on the biological and societal systems of the Nordic Seas and hence their interests are closely related to those to be discussed at the NUCCME workshop. At the workshop, a possible 14 papers with co-authors were identified, with 8 on objective 1, 2 on objective 2 and 4 for objective 3.  Over the coming months the papers will be drafted and a special issue in a leading climate change journal will be sought. 

Completed Endorsed Projects

Workshop on Basin-wide Impact of the Atlantic Multidecadal Oscillation

A workshop was convened (6-11 June 2011) to assemble all relevant information on physical and biological processes related to Atlantic Multi-decadal Oscillation (AMO) dynamics and to investigate whether AMO dynamics can be predicted. More specifically the workshop:

  • examined how the climate variability throughout the Atlantic relates to decadal-scale changes like the AMO index, and how such phenomena link to more local hydrographic features as a function of latitude and depth; the position of the north wall of the Gulf Stream; the contraction and expansion of the subpolar gyre; the northward path of the Mediterranean Outflow Water (MOW);
  • investigated the mechanistic hypotheses responsible for Atlantic multi-decadal climate variability, including changes in current systems in the North Atlantic such as the Meridional Overturning Circulation;
  • related recently observed changes in distribution, abundance and tropho-dynamics of plankton and higher trophic levels, especially fish populations, to the recent increase in the AMO index;
  • investigated how impacts vary with climate periodicity, particularly the difference in impacts on interannual climate variability compared to multi-decadal variability;
  • analyzed historical records of changes in species assemblages during previous positive (1950s and 1890s) and negative (1910s and 1970s) AMO periods and provide documentation for similar multidecadal variability in past centuries by paleo data, other kinds of proxy data, or historical descriptions; and
  • investigated if the AMO, or associated features can be predicted, using global climate models.

Workshop results (Alheit et al., 2014; have provided a better understanding of climate impacts on multi-decadal fluctuations in marine communities and should contribute to improved predictions on the impacts of future climate change on marine ecosystems and fish stocks.

Barents Sea Ecosystem Resilience under Global Environmental Change (BarEcoRe)

The objective of the BarEcoRe project was to evaluate the effects of global environmental change on the future structure and resilience of the Barents Sea ecosystem. This was undertaken by investigating the effects of past changes in climate and fisheries on the Barents Sea ecosystem, by developing indicators of ecosystem resilience, diversity and structure, and by forecasting the possible future states of the Barents Sea ecosystem under particular environmental and fisheries scenarios. The BarEcoRe project consisted of four work packages dealing with the implications of global warming and fisheries for community structure and regime shifts (WP1), trophic interactions (WP2), future distributions of fish populations (WP3), and past and future ecosystem resilience (WP4). The key questions addressed by the project were:

  • What are the key characteristics of past temporal and spatial variations in fish and benthos communities and how are these related to past climate variability and fishing pressure?
  • How does climate variability and change propagate through the Barents Sea ecosystem and influences species interactions?
  • How can the combined effects of fisheries and climate modify the spatial distribution of plankton, benthos and fish species in the Barents Sea?
  • What determines vulnerability or resilience of the Barents Sea ecosystem and how will these be affected by possible future changes in climate and fisheries regimes?
  • Can we detect early warning signals and can we evaluate management strategies with regards to ecosystem resilience?

More details and some of the results can be found at

Marine Ecosystems Comparison Norway-US (MENU II)

The Comparative Analysis of Marine Ecosystem Organization (CAMEO)-sponsored Stock Production Modeling Workshops took place 10-14 May, 2010 and on 2-6 May, 2011 in Woods Hole, Massachusetts (USA). The goal of the workshops was to use easily available data to compare ecosystems by fitting stock production models from each ecosystem and species functional groups to hopefully see patterns in sustainable ecosystem productivity using the usual comparative contrasts. The ecosystems compared were mainly, but not exclusively, sub-Arctic. They included all the original MENU regions as well as areas off eastern (i.e. Scotian Shelf) and western Canada (i.e. Strait of Georgia). The results were published in a special section of MEPS (Bundy et al., 2012;

Norwegian component of the Ecosystem Studies of Arctic and Subarctic Regions (NESSAR)

The overall goal of NESSAR was to quantify the impact of climate variability on the structure and function of Arctic marine ecosystems in Norwegian waters in order to predict the ecosystem response to possible future climate change, with particular focus on the Arctic Front. Using state-of-the-art instrumentation and methods, this interdisciplinary program studies the physical and biological processes at the front in the Barents and Norwegian seas. It collected new data never before obtained in these regions including current meter moorings, gliders.  An important aspect of NESSAR was the comparative analysis between these two regions and with other subarctic and arctic regions, to gain insights into what are fundamental processes and what are unique to specific areas. A special section on the NESSAR results was published in the Journal of Marine Systems (Drinkwater and Tande, 2014;

Marine Ecosystems Comparison Norway-US (MENU)

MENU I was a joint undertaking between Norway and the US financed by the Research Council of Norway. It conducted a workshop on marine ecosystem comparisons (March 7-9, 2007) based primarily on observational data for the eastern Bering Sea, the Gulf of Alaska, the Gulf of Maine/Georges Bank and the Norwegian and Barents seas. The results were published as part of the publication by Megrey et al. (2009) (

Ecosystem Dynamic in the Norwegian Sea and Barents Sea (ECONORTH)

The ECONORTH Symposium was (March 12 – 15, 2007) examined a suite of projects on ecosystem changes and interactions in several high latitude environments with the aim to identify processes in the ecosystem which are important for the variability in trophic transfer from plankton to fish. Also interesting are comparative studies from other areas with similar ecosystem changes or food-webs. Major topics included:Bottom-up vs. top-down effects on ecosystems; Resilience of feeding habitats and major tropho-dynamic pathways; Behaviour/life-histories/reproduction strategies; Recruitment processes; Coupled processes between physics and biology; Climatic effects on food webs; Mechanisms for large-scale changes; and Future directions in operational platforms to reveal food web dynamics. Proceedings of the ECONORTH Symposium (Pedersen et al., 2009) can be found at

Contact us

For any questions about ESSAS or further information please contact any of the ESSAS Co-chairs

Benjamin Planque
Institute of Marine Research, Bergen, Norway

Franz Mueter
University of Alaska Fairbanks, USA

Naomi Harada
Atmosphere and Ocean Research Institute, The University of Tokyo
Kashiwa, Japan