scholarly journals Vertical fluxes of nitrate in the seasonal nitracline of the Atlantic sector of the Arctic Ocean

2016 ◽  
Vol 121 (7) ◽  
pp. 5282-5295 ◽  
Author(s):  
Achim Randelhoff ◽  
Ilker Fer ◽  
Arild Sundfjord ◽  
Jean‐Éric Tremblay ◽  
Marit Reigstad
Keyword(s):  
Arctic Ocean ◽  
The Arctic ◽  
Atlantic Sector ◽  
Vertical Fluxes ◽  
The Arctic Ocean

scholarly journals Attribution of the Recent Winter Sea Ice Decline over the Atlantic Sector of the Arctic Ocean*

2015 ◽  
Vol 28 (10) ◽  
pp. 4027-4033 ◽  
Author(s):  
Doo-Sun R. Park ◽  
Sukyoung Lee ◽  
Steven B. Feldstein
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Environmental Changes ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Positive Trend ◽  
Ir Radiation ◽  
Atlantic Sector ◽  
Sea Ice Decline ◽  
The Arctic Ocean

Abstract Wintertime Arctic sea ice extent has been declining since the late twentieth century, particularly over the Atlantic sector that encompasses the Barents–Kara Seas and Baffin Bay. This sea ice decline is attributable to various Arctic environmental changes, such as enhanced downward infrared (IR) radiation, preseason sea ice reduction, enhanced inflow of warm Atlantic water into the Arctic Ocean, and sea ice export. However, their relative contributions are uncertain. Utilizing ERA-Interim and satellite-based data, it is shown here that a positive trend of downward IR radiation accounts for nearly half of the sea ice concentration (SIC) decline during the 1979–2011 winter over the Atlantic sector. Furthermore, the study shows that the Arctic downward IR radiation increase is driven by horizontal atmospheric water flux and warm air advection into the Arctic, not by evaporation from the Arctic Ocean. These findings suggest that most of the winter SIC trends can be attributed to changes in the large-scale atmospheric circulations.

chapter 7 Carbon Export Efficiency and Phytoplankton Community Composition in the Atlantic Sector of the Arctic Ocean

2017 ◽  
pp. 149-188
Author(s):  
FRÉDÉRIC A. C. LE MOIGNE ◽  
ALEX J. POULTON ◽  
STEPHANIE A. HENSON ◽  
CHRIS J. DANIELS ◽  
GLAUCIA M. FRAGOSO ◽  
...  
Keyword(s):  
Arctic Ocean ◽  
Community Composition ◽  
Phytoplankton Community ◽  
The Arctic ◽  
Carbon Export ◽  
Atlantic Sector ◽  
Phytoplankton Community Composition ◽  
The Arctic Ocean

Vertical flows of substance in the Northern arctic ocean

2021 ◽  
pp. 278-286
Author(s):  
A.N. Novigatsky ◽  
◽  
A.P. Lisitzin ◽  
V.P. Shevchenko ◽  
A.A. Klyuvitkin ◽  
...  
Keyword(s):  
Surface Layer ◽  
Arctic Ocean ◽  
Bottom Sediments ◽  
The Arctic ◽  
Chemical Components ◽  
Vertical Fluxes ◽  
Sedimentary Matter ◽  
The Arctic Ocean ◽  
Direct Calculations

The monthly, seasonal and annual quantity estimates of vertical fluxes of sedimentary matter from the surface layer of the Arctic Ocean, performed out over the years by various researchers, are the basis for direct calculations of incoming chemical components, minerals, and various pollutants to the surface layer of bottom sediments.

scholarly journals One-dimensional evolution of the upper water column in the Atlantic sector of the Arctic Ocean in winter

2017 ◽  
Vol 122 (3) ◽  
pp. 1665-1682 ◽  
Author(s):  
Ilker Fer ◽  
Algot K. Peterson ◽  
Achim Randelhoff ◽  
Amelie Meyer
Keyword(s):  
Arctic Ocean ◽  
Water Column ◽  
The Arctic ◽  
Atlantic Sector ◽  
One Dimensional ◽  
The Arctic Ocean

scholarly journals Critical role of snow on sea ice growth in the Atlantic sector of the Arctic Ocean

2018 ◽  
Author(s):  
Mats Granskog ◽  
Ioanna Merkouriadi ◽  
Bin Cheng ◽  
Robert M. Graham ◽  
Anja Rösel
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Critical Role ◽  
The Arctic ◽  
Atlantic Sector ◽  
Ice Growth ◽  
The Arctic Ocean

scholarly journals Structure and drivers of ocean mixing north of Svalbard in summer and fall 2018

2020 ◽  
Author(s):  
Zoe Koenig ◽  
Eivind H. Kolås ◽  
Ilker Fer
Keyword(s):  
Arctic Ocean ◽  
Water Column ◽  
Mixed Layer ◽  
Tidal Currents ◽  
The Arctic ◽  
Turbulent Heat ◽  
Ocean Mixing ◽  
Atlantic Sector ◽  
The Arctic Ocean ◽  
Nonlinear Relation

Abstract. Ocean mixing in the Arctic Ocean cools and freshens the Atlantic and Pacific-origin waters by mixing them with surrounding waters, which has major implications on global scale as the Arctic Ocean is a main sink for heat and salt. We investigate the drivers of ocean mixing north of Svalbard, in the Atlantic sector of the Arctic, based on observations collected during two research cruises in summer and fall 2018. In the mixed layer, there is a nonlinear relation between the layer-integrated dissipation and wind energy input; convection was active at a few stations and was responsible for enhanced turbulence compare to what was expected from the wind work alone. Summer melting of sea ice reduces the temperature, salinity and depth of the mixed layer, and increases salt and buoyancy fluxes at the base of the mixed layer. Deeper in the water column and near the seabed, tidal work is a main source of turbulence: diapycnal diffusivity in the bottom 250 m of the water column is enhanced during strong tidal currents, reaching on average 10−3 m2 s−1. The average profile of diffusivity decays with distance from seabed with an e-folding scale of 22 m compared to 18 m in conditions with weaker tidal currents. A nonlinear relation is inferred between the depth-integrated dissipation in the bottom 250 m of the water column and the tidally-driven bottom drag and is used to estimate the bottom dissipation along the continental slope of the Eurasian Basin. Computation of the inverse Froude number suggests that nonlinear internal waves forced by the diurnal tidal activity (K1 constituent) can develop north of Svalbard and in the Laptev and Kara Seas, with the potential to mix the entire water column vertically. Estimates of vertical turbulent heat flux from the Atlantic Water layer up to the mixed layer reaches 30 W m−2 in the core of the boundary current, and is on average 8 W m−2, accounting for ∼ 1 % of the total heat loss of the Atlantic layer in the region.

scholarly journals The Arctic sea ice cover of 2016: a year of record-low highs and higher-than-expected lows

2018 ◽  
Vol 12 (2) ◽  
pp. 433-452 ◽  
Author(s):  
Alek A. Petty ◽  
Julienne C. Stroeve ◽  
Paul R. Holland ◽  
Linette N. Boisvert ◽  
Angela C. Bliss ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
North Atlantic ◽  
Ice Cover ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Sea Ice Extent ◽  
Atlantic Sector ◽  
Arctic Sea ◽  
The Arctic Ocean

Abstract. The Arctic sea ice cover of 2016 was highly noteworthy, as it featured record low monthly sea ice extents at the start of the year but a summer (September) extent that was higher than expected by most seasonal forecasts. Here we explore the 2016 Arctic sea ice state in terms of its monthly sea ice cover, placing this in the context of the sea ice conditions observed since 2000. We demonstrate the sensitivity of monthly Arctic sea ice extent and area estimates, in terms of their magnitude and annual rankings, to the ice concentration input data (using two widely used datasets) and to the averaging methodology used to convert concentration to extent (daily or monthly extent calculations). We use estimates of sea ice area over sea ice extent to analyse the relative “compactness” of the Arctic sea ice cover, highlighting anomalously low compactness in the summer of 2016 which contributed to the higher-than-expected September ice extent. Two cyclones that entered the Arctic Ocean during August appear to have driven this low-concentration/compactness ice cover but were not sufficient to cause more widespread melt-out and a new record-low September ice extent. We use concentration budgets to explore the regions and processes (thermodynamics/dynamics) contributing to the monthly 2016 extent/area estimates highlighting, amongst other things, rapid ice intensification across the central eastern Arctic through September. Two different products show significant early melt onset across the Arctic Ocean in 2016, including record-early melt onset in the North Atlantic sector of the Arctic. Our results also show record-late 2016 freeze-up in the central Arctic, North Atlantic and the Alaskan Arctic sector in particular, associated with strong sea surface temperature anomalies that appeared shortly after the 2016 minimum (October onwards). We explore the implications of this low summer ice compactness for seasonal forecasting, suggesting that sea ice area could be a more reliable metric to forecast in this more seasonal, “New Arctic”, sea ice regime.

scholarly journals Critical Role of Snow on Sea Ice Growth in the Atlantic Sector of the Arctic Ocean

2017 ◽  
Vol 44 (20) ◽  
pp. 10,479-10,485 ◽  
Author(s):  
Ioanna Merkouriadi ◽  
Bin Cheng ◽  
Robert M. Graham ◽  
Anja Rösel ◽  
Mats A. Granskog
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Critical Role ◽  
The Arctic ◽  
Atlantic Sector ◽  
Ice Growth ◽  
The Arctic Ocean

scholarly journals Atmospheric Trends Over the Arctic Ocean in Simulations from the Coordinated Regional Downscaling Experiment (CORDEX) and Their Driving GCMs

2021 ◽  
Author(s):  
Cathy Reader ◽  
Nadja Steiner
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
General Circulation ◽  
Climate Models ◽  
Circulation Model ◽  
The Arctic ◽  
Atlantic Sector ◽  
Near Surface ◽  
The Arctic Ocean ◽  
Regional Downscaling

Abstract The Arctic Coordinated Regional Downscaling Experiment (Arctic-CORDEX) uses regional climate models (RCMs) to downscale selected Fifth Coupled Model Intercomparison Project (CMIP5) simulations, allowing trend validation and projection on subregional scales. For 1986-2015, the CORDEX seasonal-average near-surface temperature (tas), wind speed (sfcWind), precipitation (pr) and snowfall (prsn) trends are consistent with the ERA5 analysis for the Arctic Ocean regions considered. The projected Representative Concentration Pathway 8.5 (RCP8.5) 2016-2100 subregional annual tas trends range from 0.03 to 0.18 K/year. Projected annual pr and prsn trends have a large inter-model spread centered around approximately 5.0x10−8 mm/s/year and -5.0x10−8 mm/s/year, respectively, while projected sfcWind summer and winter trends range between 0.0 and 0.4 m/s/year. For all variables except prsn, and sometimes total precipitation, the driving general circulation model (GCM) dominates the trends, however there is a tendency for the GCMs to underestimate the sfcWind trends compared to the downscaled simulations. Subtracting the Arctic-Ocean mean from subregional trends reveals a consistent, qualitative anomaly pattern in several variables and seasons characterized by greater-than or average trends in the central and Siberian Arctic Ocean and lesser or average trends in the Atlantic Sector and the Bering Sea, related to summer sea-ice trends. In particular, a strong proportional relationship exists between the summer sea-ice concentration and fall tas and sfcWind trend anomalies. The RCP4.5 annual, multi-model mean trends are 35-55% of the corresponding RCP8.5 trends for most variables and subregions.

scholarly journals Wind and Wave Climate in the Arctic Ocean as Observed by Altimeters

2016 ◽  
Vol 29 (22) ◽  
pp. 7957-7975 ◽  
Author(s):  
Qingxiang Liu ◽  
Alexander V. Babanin ◽  
Stefan Zieger ◽  
Ian R. Young ◽  
Changlong Guan
Keyword(s):  
Arctic Ocean ◽  
Wave Height ◽  
Large Scale ◽  
Chukchi Sea ◽  
Wave Climate ◽  
The Arctic ◽  
Atlantic Sector ◽  
Pacific Side ◽  
The Arctic Ocean ◽  
The Arctic Oscillation

Abstract Twenty years (1996–2015) of satellite observations were used to study the climatology and trends of oceanic winds and waves in the Arctic Ocean in the summer season (August–September). The Atlantic-side seas, exposed to the open ocean, host more energetic waves than those on the Pacific side. Trend analysis shows a clear spatial (regional) and temporal (interannual) variability in wave height and wind speed. Waves in the Chukchi Sea, Beaufort Sea (near the northern Alaska), and Laptev Sea have been increasing at a rate of 0.1–0.3 m decade−1, found to be statistically significant at the 90% level. The trend of waves in the Greenland and Barents Seas, on the contrary, is weak and not statistically significant. In the Barents and Kara Seas, winds and waves initially increased between 1996 and 2006 and later decreased. Large-scale atmospheric circulations such as the Arctic Oscillation and Arctic dipole anomaly have a clear impact on the variation of winds and waves in the Atlantic sector. Comparison between altimeter observations and ERA-Interim shows that the reanalysis winds are on average 1.6 m s−1 lower in the Arctic Ocean, which translates to a low bias of significant wave height (−0.27 m) in the reanalysis wave data.

Sign in / Sign up

Export Citation Format

Share Document