scholarly journals Paleo Cruise 2018

2020 ◽  
Author(s):  
Katrine Husum ◽  
Ulysses Ninnemann ◽  
Tom Arne Rydningen ◽  
Elisabeth Alve ◽  
Naima E B Altuna ◽  
...  
Keyword(s):  
Sea Ice ◽  
Time Scales ◽  
Barents Sea ◽  
Sediment Cores ◽  
Ice Cover ◽  
Atlantic Water ◽  
Natural Variability ◽  
Argo Float ◽  
The Barents Sea ◽  
Through Flow

The Nansen Legacy paleo cruise was carried out from September 26 to October 20, 2018 with RV “Kronprins Haakon”. The cruise took place in the northern Barents Sea and the Nansen Basin, and it went through the sea ice to 83.3 N. The overriding objective of the cruise was to reconstruct the natural variability and range of sea ice cover and Atlantic Water through flow in the Barents Sea on longer time scales. During the cruise four ocean moorings were deployed in northwest Barents Sea, where one ARGO float was also deployed. Twelve “paleo stations” were identified using multibeam and sub bottom profilers. At these stations, short and long sediment cores were obtained. This cruise report gives an overview of methods used and samples taken. 

Postglacial paleoceanography and paleoenvironments in the northwestern Barents Sea

2019 ◽  
Vol 92 (2) ◽  
pp. 430-449 ◽  
Author(s):  
Elena Ivanova ◽  
Ivar Murdmaa ◽  
Anne de Vernal ◽  
Bjørg Risebrobakken ◽  
Alexander Peyve ◽  
...  
Keyword(s):  
Sea Ice ◽  
Barents Sea ◽  
Sediment Cores ◽  
Ice Cover ◽  
Atlantic Water ◽  
The Arctic ◽  
High Productivity ◽  
Surface Warming ◽  
The Barents Sea ◽  
Suitable Location

AbstractThe Barents Sea offers a suitable location for documenting advection of warm and saline Atlantic Water (AW) into the Arctic and its impact on deglaciation and postglacial conditions. We investigate the timing, succession, and mechanisms of the transition from proximal glaciomarine to marine environment in the northwestern Barents Sea. Two studied sediment cores demonstrate diachronous retreat of the grounded ice sheet from the Kvitøya Trough (core S2528) to Erik Eriksen Trough (core S2519). Oxygen isotope records from core S2528 depict a two-step pattern, with lower δ18O values prior to the Younger Dryas (YD), and higher values afterward because of advection of the more saline, 18O-enriched AW. At this location, subsurface AW penetration increased during the Allerød and YD/Preboreal transition. In the study area, foraminiferal and dinocyst data from the YD interval suggest cold conditions, extensive sea-ice cover, and brine formation, along with the flow of chilled AW at subsurface and the development of a high-productivity polynya in the Erik Eriksen Trough. Dense winter sea-ice cover with seasonal productivity persisted in the Kvitøya Trough area during the early Holocene, whereas surface warming seems to have occurred during the middle Holocene interval.

Palynological evidence of sea-surface conditions in the Barents Sea off northeast Svalbard during the postglacial period

2020 ◽  
pp. 1-15
Author(s):  
Camille Brice ◽  
Anne de Vernal ◽  
Elena Ivanova ◽  
Simon van Bellen ◽  
Nicolas Van Nieuwenhove
Keyword(s):  
Sea Ice ◽  
Surface Waters ◽  
Barents Sea ◽  
Ice Cover ◽  
Atlantic Water ◽  
Transitional Period ◽  
Sea Surface ◽  
Sea Surface Salinity ◽  
Surface Conditions ◽  
The Barents Sea

Abstract Postglacial changes in sea-surface conditions, including sea-ice cover, summer temperature, salinity, and productivity were reconstructed from the analyses of dinocyst assemblages in core S2528 collected in the northwestern Barents Sea. The results show glaciomarine-type conditions until about 11,300 ± 300 cal yr BP and limited influence of Atlantic water at the surface into the Barents Sea possibly due to the proximity of the Svalbard-Barents Sea ice sheet. This was followed by a transitional period generally characterized by cold conditions with dense sea-ice cover and low-salinity pulses likely related to episodic freshwater or meltwater discharge, which lasted until 8700 ± 700 cal yr BP. The onset of “interglacial” conditions in surface waters was marked by a major change in dinocyst assemblages, from dominant heterotrophic to dominant phototrophic taxa. Until 4100 ± 150 cal yr BP, however, sea-surface conditions remained cold, while sea-surface salinity and sea-ice cover recorded large amplitude variations. By ~4000 cal yr BP optimum sea-surface temperature of up to 4°C in summer and maximum salinity of ~34 psu suggest enhanced influence of Atlantic water, and productivity reached up to 150 gC/m2/yr. After 2200 ± 1300 cal yr BP, a distinct cooling trend accompanied by sea-ice spreading characterized surface waters. Hence, during the Holocene, with exception of an interval spanning about 4000 to 2000 cal yr BP, the northern Barents Sea experienced harsh environments, relatively low productivity, and unstable conditions probably unsuitable for human settlements.

Relationships between wintertime sea ice cover in the Barents Sea and ocean temperature anomalies in the era of satellite observations

2020 ◽  
pp. 1-65
Author(s):  
Pawel Schlichtholz
Keyword(s):  
Sea Ice ◽  
Barents Sea ◽  
Early Period ◽  
Ice Cover ◽  
Atlantic Water ◽  
The Arctic ◽  
Ocean Temperature ◽  
Temperature Anomalies ◽  
The Barents Sea ◽  
Skill Scores

AbstractInvestigation of the predictability of sea ice cover in the Barents Sea is of paramount importance since sea ice changes in this part of the Arctic not only affect local marine ecosystems and human activities but may also influence weather and climate in northern mid-latitudes. Here, observational data from the period 1981-2018 are used to identify statistical linkages of wintertime sea ice cover in the Barents Sea region to preceding sea surface temperature (SST) and Atlantic water temperature anomalies in that region. We find that the ocean temperature anomalies formed by local air-sea interactions during the winter-to-spring season are a significant source of predictability for sea ice area (SIA) in the Barents Sea region the following winter. Optimal areas for constructing SST predictors of Barents Sea SIA and skill scores from retrospective statistical forecasts are shown to differ between the periods to and since the onset of rapid sea ice decline in the region. In the EARLY period (1982-2003), springtime SSTs in the western Barents Sea predicted 44% of the variance of the following winter Barents Sea SIA. In the LATE period (2003-2017), springtime SSTs in the southern Barents Sea predicted 70% of the variance of the following winter Barents Sea SIA. Regression analysis suggests that feedbacks from anomalous winds may be important for the predictability of wintertime sea ice cover in the Barents Sea region.

scholarly journals Does Arctic warming reduce preservation of organic matter in Barents Sea sediments?

2020 ◽  
Vol 378 (2181) ◽  
pp. 20190364 ◽  
Author(s):  
Johan C. Faust ◽  
Mark A. Stevenson ◽  
Geoffrey D. Abbott ◽  
Jochen Knies ◽  
Allyson Tessin ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Sea Ice ◽  
Surface Sediments ◽  
Barents Sea ◽  
Ice Cover ◽  
Atlantic Water ◽  
Sea Surface ◽  
Arctic Warming ◽  
Reactive Iron ◽  
The Barents Sea

Over the last few decades, the Barents Sea experienced substantial warming, an expansion of relatively warm Atlantic water and a reduction in sea ice cover. This environmental change forces the entire Barents Sea ecosystem to adapt and restructure and therefore changes in pelagic–benthic coupling, organic matter sedimentation and long-term carbon sequestration are expected. Here we combine new and existing organic and inorganic geochemical surface sediment data from the western Barents Sea and show a clear link between the modern ecosystem structure, sea ice cover and the organic carbon and CaCO 3 contents in Barents Sea surface sediments. Furthermore, we discuss the sources of total and reactive iron phases and evaluate the spatial distribution of organic carbon bound to reactive iron. Consistent with a recent global estimate we find that on average 21.0 ± 8.3 per cent of the total organic carbon is associated to reactive iron (fOC-Fe R ) in Barents Sea surface sediments. The spatial distribution of fOC-Fe R , however, seems to be unrelated to sea ice cover, Atlantic water inflow or proximity to land. Future Arctic warming might, therefore, neither increase nor decrease the burial rates of iron-associated organic carbon. However, our results also imply that ongoing sea ice reduction and the associated alteration of vertical carbon fluxes might cause accompanied shifts in the Barents Sea surface sedimentary organic carbon content, which might result in overall reduced carbon sequestration in the future. This article is part of the theme issue ‘The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning’.

scholarly journals Wind-Driven Atlantic Water Flow as a Direct Mode for Reduced Barents Sea Ice Cover

2017 ◽  
Vol 30 (2) ◽  
pp. 803-812 ◽  
Author(s):  
Vidar S. Lien ◽  
Pawel Schlichtholz ◽  
Øystein Skagseth ◽  
Frode B. Vikebø
Keyword(s):  
Sea Ice ◽  
Heat Transport ◽  
Ocean Circulation ◽  
Barents Sea ◽  
Heat Content ◽  
Circulation Model ◽  
Ice Cover ◽  
Atlantic Water ◽  
Direct Role ◽  
The Barents Sea

Variability in the Barents Sea ice cover on interannual and longer time scales has previously been shown to be governed by oceanic heat transport. Based on analysis of observations and results from an ocean circulation model during an event of reduced sea ice cover in the northeastern Barents Sea in winter 1993, it is shown that the ocean also plays a direct role within seasons. Positive wind stress curl and associated Ekman divergence causes a coherent increase in the Atlantic water transport along the negative thermal gradient through the Barents Sea. The immediate response connected to the associated local winds in the northeastern Barents Sea is a decrease in the sea ice cover due to advection. Despite a subsequent anomalous ocean-to-air heat loss on the order of 100 W m−2 due to the open water, the increase in the ocean heat content caused by the circulation anomaly reduced refreezing on a time scale of order one month. Furthermore, it is found that coherent ocean heat transport anomalies occurred more frequently in the latter part of the last five decades during periods of positive North Atlantic Oscillation index, coinciding with the Barents Sea winter sea ice cover decline from the 1990s and onward.

scholarly journals Atlantic water temperature and climate in the Barents Sea, 2000–2009

2012 ◽  
Vol 69 (5) ◽  
pp. 833-840 ◽  
Author(s):  
Vladimir D. Boitsov ◽  
Alexey L. Karsakov ◽  
Alexander G. Trofimov
Keyword(s):  
Water Temperature ◽  
Barents Sea ◽  
Ice Cover ◽  
Atlantic Water ◽  
Climate Index ◽  
Mean Annual Temperature ◽  
Positive Trend ◽  
Late 20Th Century ◽  
The Barents Sea ◽  
Using Data

Abstract Boitsov, V. D., Karsakov, A. L., and Trofimov, A. G. 2012. Atlantic water temperature and climate in the Barents Sea, 2000–2009. – ICES Journal of Marine Science, 69: 833–840. Year-to-year variability in the temperature of Atlantic water (AW), which has a strong influence on the marine climate and ecosystem of the Barents Sea, was analysed using data from the Kola Section. With a positive trend in mean annual temperature during the late 20th century, only positive anomalies were registered during the past decade. In nine of those years, the temperature was warmer than the 1951–2000 long-term mean by 0.5–1.2°C, and in 2006, the historical maximum for the 110-year period of observations along the section was recorded. High air and water temperature coincided with reduced sea-ice cover, especially between October and April, when there is seasonal enlargement of the ice-covered area. An integral climate index (CI) of the Barents Sea based on the variability in temperature of AW, air temperature, and ice cover is presented. A prediction of future Barents Sea climate to 2020 is given by extrapolating the sixth degree polynomial approximating the CI.

Transformation of Atlantic Water in the Barents Sea in winter: overview of “Transarctika-2019” cruise results

2020 ◽  
Author(s):  
Vladimir Ivanov ◽  
Ivan Frolov ◽  
Kirill Filchuk
Keyword(s):  
Characteristic Feature ◽  
Sea Ice ◽  
Arctic Ocean ◽  
Water Column ◽  
Barents Sea ◽  
Atlantic Water ◽  
The Arctic ◽  
The Barents Sea ◽  
Open Sea ◽  
The Arctic Ocean

<p>In the recent few years the topic of accelerated sea ice loss, and related changes in the vertical structure of water masses in the East-Atlantic sector of the Arctic Ocean, including the Barents Sea and the western part of the Nansen Basin, has been in the foci of multiple studies. This region even earned the name the “Arctic warming hotspot”, due to the extreme retreat of sea ice and clear signs of change in the vertical hydrographic structure from the Arctic type to the sub-Arctic one. A gradual increase in temperature and salinity in this area has been observed since the mid-2000s. This trend is hypothetically associated with a general decrease in the volume of sea ice in the Arctic Ocean, which leads to a decrease of ice import in the Barents Sea, salinization, weakening of density stratification, intensification of vertical mixing and an increase of heat and salt fluxes from the deep to the upper mixed layer. The result of such changes is a further reduction of sea ice, i.e. implementation of positive feedback, which is conventionally refereed as the “atlantification. Due to the fact that the Barents Sea is a relatively shallow basin, the process of atlantification might develop here much faster than in the deep Nansen Basin. Thus, theoretically, the hydrographic regime in the northern part of the Barents Sea may rapidly transform to a “Nordic Seas – wise”, a characteristic feature of which is the year-round absence of the ice cover with debatable consequences for the climate and ecosystem of the region and adjacent land areas. Due to the obvious reasons, historical observations in the Barents Sea mostly cover the summer season. Here we present a rare oceanographic data, collected during the late winter - early spring in 2019. Measurements were occupied at four sequential oceanographic surveys from the boundary between the Norwegian Sea and the Barents Sea – the so called Barents Sea opening to the boundary between the Barents Sea and the Kara Sea. Completed hydrological sections allowed us to estimate the contribution of the winter processes in the Atlantic Water transformation at the end of the winter season. Characteristic feature of the observed transformation is the homogenization of the near-to-bottom part of the water column with remaining stratification in the upper part. A probable explanation of such changes is the dominance of shelf convection and cascading of dense water over the open sea convection. In this case, complete homogenization of the water column does not occur, since convection in the open sea is impeded by salinity and density stratification, which is maintained by melting of the imported sea ice in the relatively warm water. The study was supported by RFBR grant # 18-05-60083.</p>

Linear predictability of Barents Sea ice cover: effects of coupling and resolution

2020 ◽  
Author(s):  
Chuncheng Guo ◽  
Aleksi Nummelin
Keyword(s):  
Sea Ice ◽  
Response Function ◽  
Barents Sea ◽  
Heat Content ◽  
Coupled System ◽  
Ice Cover ◽  
Statistical Prediction ◽  
Lead Times ◽  
The Barents Sea ◽  
Small Set

<p>Wintertime Barents Sea ice cover has been strongly linked to heat transport through the Barents Sea opening and Barents Sea heat content. Previous studies have shown predictability at seasonal timescales with short lead times. However, studies that have used statistical prediction have focused on a small set of predictors in the vicinity of the Barents Sea. Here we will extend the analysis further south following the path of the Norwegian Atlantic Current and show that monthly predictability with lead times up to 1-2 years can be achieved in CMIP6 models using Climate Response Function (CRF's). We further examine the effects of model resolution and coupling in the predictability and compare the results to CRF derived from observations. Our results suggest that higher resolution generally leads to stronger predictability and the fully coupled system provides the most realistic response function. The ocean provides a narrow range of lead times corresponding to an advective timescale, while coupling to the atmosphere broadens the lead times that are important for prediction. Finally, we show that even the upstream sea surface temperatures provide relatively high predictability of the Barents Sea ice cover both in the models and in the observations.</p>

scholarly journals Feedback Mechanism Among Decadal Oscillations in Northern Hemisphere Atmospheric Circulation, Sea Ice, and Ocean Circulation

1990 ◽  
Vol 14 ◽  
pp. 120-123 ◽  
Author(s):  
M Ikeda
Keyword(s):  
Sea Ice ◽  
Atmospheric Circulation ◽  
Wind Stress ◽  
Ocean Circulation ◽  
Barents Sea ◽  
Decadal Variability ◽  
Ice Cover ◽  
Low Pressure ◽  
Feedback Mechanism ◽  
The Barents Sea

Decadal oscillations of the ice cover in the Barents Sea are examined for the period since 1950. They are highly correlated with atmospheric circulation when that circulation has an anomalous low pressure over the Barents Sea and Eurasian Basin, while the ice cover is weakly correlated with local air temperature. A feedback mechanism between Barents Sea ice and the atmospheric circulation is suggested; increased cyclonic wind-stress curl reduces cold Arctic flow to the Barents Sea and reduces the sea ice. The reduced ice cover encourages heat flux from the Barents Sea to the atmosphere, tending to reinforce the low pressure. This positive feedback amplifies the oscillations of the air–ice–ocean system driven by external forcing with relatively weak decadal variability. A two-level ocean model, which is driven by prescribed buoyancy flux and wind stresses, confirms that Arctic outflow to the Barents Sea decreases during a cyclonic wind stress.

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