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norskBlar i forfatter "Hop, Haakon"
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Panel-based Assessment of Ecosystem Condition of Norwegian Barents Sea Shelf Ecosystems - Appendices
(Research report; Forskningsrapport, 2023-03-16) -
Pelagic Ecosystem Characteristics Across the Atlantic Water Boundary Current from Rijpfjorden, Svalbard, to the Arctic Ocean during Summer (2010-2014)
(Journal article; Peer reviewed, 2019-04-09)The northern coast of Svalbard contains high-arctic fjords, such as Rijpfjorden (80°N 22°30′E). This area has experienced higher sea and air temperatures and less sea ice in recent years, and models predict increasing temperatures in this region. Part of the West Spitsbergen Current (WSC), which transports relatively warm Atlantic water along the continental slope west of Svalbard, bypasses these ... -
Pelagic occurrences of the ice amphipod Apherusa glacialis throughout the Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-10)<i>Apherusa glacialis</i> is a common, sea ice-associated amphipod found throughout the Arctic Ocean and has long been considered permanently associated with the sea ice habitat. However, pelagic occurrences of <i>A. glacialis</i> have also been reported. It was recently suggested that <i>A. glacialis</i> overwinters at depth within the Atlantic-water inflow near Svalbard, to avoid being exported ... -
Pelagic occurrences of the ice amphipod Apherusa glacialis throughout the Arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-10)<i>Apherusa glacialis</i> is a common, sea ice-associated amphipod found throughout the Arctic Ocean and has long been considered permanently associated with the sea ice habitat. However, pelagic occurrences of <i>A. glacialis</i> have also been reported. It was recently suggested that <i>A. glacialis</i> overwinters at depth within the Atlantic-water inflow near Svalbard, to avoid being exported ... -
A red tide in the pack ice of the Arctic Ocean
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-07-02)In the Arctic Ocean ice algae constitute a key ecosystem component and the ice algal spring bloom a critical event in the annual production cycle. The bulk of ice algal biomass is usually found in the bottom few cm of the sea ice and dominated by pennate diatoms attached to the ice matrix. Here we report a red tide of the phototrophic ciliate <i>Mesodinium rubrum</i> located at the ice-water interface ... -
Regulation of gene expression is associated with tolerance of the Arctic copepod Calanus glacialis to CO2-acidified sea water
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-08-02)Ocean acidification is the increase in seawater pCO2 due to the uptake of atmospheric anthropogenic CO2, with the largest changes predicted to occur in the Arctic seas. For some marine organisms, this change in pCO2, and associated decrease in pH, represents a climate change-related stressor. In this study, we investigated the gene expression patterns of nauplii of the Arctic copepod Calanus glacialis ... -
A review of the scientific knowledge of the seascape off Dronning Maud Land, Antarctica
(Journal article; Tidsskriftartikkel; Peer reviewed, 2022-08-29)Despite the exclusion of the Southern Ocean from assessments of progress towards achieving the Convention on Biological Diversity (CBD) Strategic Plan, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) has taken on the mantle of progressing eforts to achieve it. Within the CBD, Aichi Target 11 represents an agreed commitment to protect 10% of the global coastal and ... -
Sea ice meiofauna distribution on local to pan-Arctic scales
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-29)Arctic sea ice provides microhabitats for biota that inhabit the liquid‐filled network of brine channels and the ice–water interface. We used meta‐analysis of 23 published and unpublished datasets comprising 721 ice cores to synthesize the variability in composition and abundance of sea ice meiofauna at spatial scales ranging from within a single ice core to pan‐Arctic and seasonal scales. Two‐thirds ... -
Sea ice thermohaline dynamics and biogeochemistry in the Arctic Ocean: Empirical and model results
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-11)Large changes in the sea ice regime of the Arctic Ocean have occurred over the last decades justifying the development of models to forecast sea ice physics and biogeochemistry. The main goal of this study is to evaluate the performance of the Los Alamos Sea Ice Model (CICE) to simulate physical and biogeochemical properties at time scales of a few weeks and to use the model to analyze ice algal ... -
Seasonal plankton dynamics in Kongsfjorden during two years of contrasting environmental conditions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-24)Seasonal plankton time-series data are presented from Kongsfjorden from two years with contrasting environmental conditions. Kongsfjorden (west coast of Spitsbergen – 79°N) integrates inputs from Atlantic and Arctic waters, and glacier run-off, and is thus a prime location to study impacts on ecosystem dynamics of key environmental drivers that are relevant across the Arctic. Despite extensive ... -
The seeding of ice algal blooms in Arctic pack ice: The multiyear ice seed repository hypothesis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-03)During the Norwegian young sea ICE expedition (N-ICE2015) from January to June 2015 the pack ice in the Arctic Ocean north of Svalbard was studied during four drifts between 83° and 80°N. This pack ice consisted of a mix of second year, fi rst year, and young ice. The physical properties and ice algal community composition was investigated in the three different ice types during the ... -
Spring bloom dynamics in Kongsfjorden, Svalbard: nutrients, phytoplankton, protozoans and primary production
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)The marine ecosystem in Kongsfjorden (79 N), a glacial fjord in Svalbard, is to a large extent well known with regard to hydrography, mesozooplankton and higher trophic levels. Research on primary production and lower trophic levels is still scare and especially investigations from winter and spring periods. The spring bloom dynamics in Kongsfjordenwere investigated in 2002. The development in ... -
Still Arctic? — The changing Barents Sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-13)The Barents Sea is one of the Polar regions where current climate and ecosystem change is most pronounced. Here we review the current state of knowledge of the physical, chemical and biological systems in the Barents Sea. Physical conditions in this area are characterized by large seasonal contrasts between partial sea-ice cover in winter and spring versus predominantly open water in summer and ... -
Summer and winter MgCO3 levels in the skeletons of Arctic bryozoans
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-02)<p>In the Arctic, seasonal patterns in seawater biochemical conditions are shaped by physical, chemical, and biological processes related to the alternation of seasons, i.e. winter polar night and summer midnight sun. In summertime, CO<sub>2</sub> concentration is driven by photosynthetic activity of autotrophs which raises seawater pH and carbonate saturation state (Ω). In addition, restriction of ... -
Tidewater glaciers and bedrock characteristics control the phytoplankton growth environment in a fjord in the arctic
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-05-31)Meltwater discharge from tidewater glaciers impacts the adjacent marine environment. Due to the global warming, tidewater glaciers are retreating and will eventually terminate on land. Yet, the mechanisms through which meltwater runoff and subglacial discharge from tidewater glaciers influence marine primary production remain poorly understood, as data in close proximity to glacier fronts are scarce. ... -
Zooplankton in Svalbard fjords on the Atlantic–Arctic boundary
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-07-01)Zooplankton abundance and community structures were studied in three west Spitsbergen fjords at the beginning of the warm phase, which seem to have entered in 2006. Sampling was conducted in summer 2007 at stations distributed along transects in Hornsund, Isfjorden and Kongsfjorden. Variations in zooplankton standing stocks and community structures (assessing taxonomic diversity and zoogeographical ...
