Alexandrium algae, saxitoxin, and clams: Bering Strait and Chukchi Sea 2018–2019

2019 ◽  
Author(s):  
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...  
Keyword(s):  
Chukchi Sea ◽  
Bering Strait

scholarly journals Calcium carbonate saturation in the surface water of the Arctic Ocean: undersaturation in freshwater influenced shelves

2009 ◽  
Vol 6 (11) ◽  
pp. 2421-2431 ◽  
Author(s):  
M. Chierici ◽  
A. Fransson
Keyword(s):  
Calcium Carbonate ◽  
Surface Water ◽  
Cold Water ◽  
Dissolved Inorganic Carbon ◽  
Chukchi Sea ◽  
Total Alkalinity ◽  
The Arctic ◽  
Subsurface Water ◽  
Chukchi Peninsula ◽  
Bering Strait

Abstract. In the summer of 2005, we sampled surface water and measured pH and total alkalinity (AT) underway aboard IB Oden along the Northwest Passage from Cape Farewell (South Greenland) to the Chukchi Sea. We investigated the variability of carbonate system parameters, focusing particularly on carbonate concentration [CO32−] and calcium carbonate saturation states, as related to freshwater addition, biological processes and physical upwelling. Measurements on AT, pH at 15°C, salinity (S) and sea surface temperature (SST), were used to calculate total dissolved inorganic carbon (CT), [CO32−] and the saturation of aragonite (ΩAr) and calcite (ΩCa) in the surface water. The same parameters were measured in the water column of the Bering Strait. Some surface waters in the Canadian Arctic Archipelago (CAA) and on the Mackenzie shelf (MS) were found to be undersaturated with respect to aragonite (ΩAr<1). In these areas, surface water was low in AT and CT (<1500 μmol kg−1) relative to seawater and showed low [CO32−]. The low saturation states were probably due to the likely the effect of dilution due to freshwater addition by sea ice melt (CAA) and river runoff (MS). High AT and CT and low pH, corresponded with the lowest [CO32−], ΩAr and ΩCa, observed near Cape Bathurst and along the South Chukchi Peninsula. This was linked to the physical upwelling of subsurface water with elevated CO2. The highest surface ΩAr and ΩCa of 3.0 and 4.5, respectively, were found on the Chukchi Sea shelf and in the cold water north of Wrangel Island, which is heavily influenced by high CO2 drawdown and lower CT from intense biological production. In the western Bering Strait, the cold and saline Anadyr Current carries water that is enriched in AT and CT from enhanced organic matter remineralization, resulting in the lowest ΩAr (~1.2) of the area.

Optical properties and molecular diversity of dissolved organic matter in the Bering Strait and Chukchi Sea

2017 ◽  
Vol 144 ◽  
pp. 104-111 ◽  
Author(s):  
Michael Gonsior ◽  
Jenna Luek ◽  
Philippe Schmitt-Kopplin ◽  
Jacqueline M. Grebmeier ◽  
Lee W. Cooper
Keyword(s):  
Organic Matter ◽  
Optical Properties ◽  
Dissolved Organic Matter ◽  
Molecular Diversity ◽  
Chukchi Sea ◽  
Bering Strait

Carbonate chemistry dynamics in Bering Strait and the Chukchi Sea

2002 ◽  
Vol 55 (1-2) ◽  
pp. 77-94 ◽  
Author(s):  
I.I Pipko ◽  
I.P Semiletov ◽  
P.Ya Tishchenko ◽  
S.P Pugach ◽  
J.P Christensen
Keyword(s):  
Chukchi Sea ◽  
Bering Strait ◽  
Carbonate Chemistry ◽  
Chemistry Dynamics

Cascading and the pathways of the key biogeochemical tracers in the Canadian Basin: from models and observations.

2020 ◽  
Author(s):  
Maria Luneva ◽  
Yevgeny Aksenov ◽  
Vladimir Ivanov ◽  
Stephen Kelly ◽  
Fedor Tuzov
Keyword(s):  
Chukchi Sea ◽  
Gravity Current ◽  
The Arctic ◽  
Bering Strait ◽  
Low Salinity ◽  
Beaufort Gyre ◽  
Pacific Waters ◽  
Brine Rejection ◽  
Ice Model

&lt;p&gt;We explore dense water cascading (DWC; a type of bottom-trapped gravity current) on multi-decadal time scales using a pan-Arctic regional ocean-ice model. DWC is particularly important in the Arctic Ocean as the main mechanism of ventilation of interior waters when open ocean convection is blocked by strong density stratification. We identify the locations where the most intense DWC events occur and evaluate the associated cross-shelf mass, heat and salt fluxes.&amp;#160;&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;A detailed analysis of specific cascading sites around the Beaufort Gyre and adjacent regions is performed. We find that autumn upwelling of warm and saltier Atlantic waters on the shelf and subsequent cooling and mixing of uplifted waters trigger the cascading on the West Chukchi Sea shelf break. We also perform Lagragian particle tacking of low salinity Pacific waters originating at the surface in the Bering Strait; these waters are shown to be modified by brine rejection and cooling, and through subsequent mixing become dense enough to reach depths of 160-200m and below. We examine the role of cascading and shelf upwelling on the shelf waters transformation, pathways and spread of the biological important tracers (O18, Si., DIC snd DIN).&lt;/p&gt;

Migration and Feeding of the Gray Whale (Eschrichtius gibbosus)

1962 ◽  
Vol 19 (5) ◽  
pp. 815-838 ◽  
Author(s):  
Gordon C. Pike
Keyword(s):  
British Columbia ◽  
Bering Sea ◽  
Chukchi Sea ◽  
Close Contact ◽  
Gulf Of Alaska ◽  
Bering Strait ◽  
Visual Contact ◽  
Gray Whales ◽  
Baleen Whales ◽  
The Bering Sea

Observations of gray whales from the coasts of British Columbia, Washington, and Alaska are compared with published accounts in order to re-assess knowledge of migration and feeding of the American herd. Source of material is mainly from lighthouses and lightships.The American herd of gray whales retains close contact with the shore during migration south of Alaska. Off Washington and British Columbia the northward migration begins in February, ends in May, and is at a peak during the first two weeks in April; the southward migration occurs in December and January, and is at a peak in late December. Northward migrants stop occasionally to rest or feed; southward migrants are travelling faster and appear not to stop to rest or feed during December and January. Gray whales seen off British Columbia, sometimes in inside protected waters, from June through October, probably remain in this area throughout the summer and fall months.Available evidence suggests that gray whales retain contact with the coast while circumscribing the Gulf of Alaska, enter the Bering Sea through eastern passages of the Aleutian chain, and approach St. Lawrence Island by way of the shallow eastern part of the Bering Sea. Arriving off the coast of St. Lawrence Island in May and June the herd splits with some parts dispersing along the Koryak coast and some parts continuing northward as the ice retreats through Bering Strait. Gray whales feed in the waters of the Chukchi Sea along the Siberian and Alaskan coasts in July, August and September. Advance of the ice through Bering Strait in October initiates the southern migration for most of the herd. In summering areas, in northern latitudes, gray whales feed in shallow waters on benthic and near-benthic organisms, mostly amphipods.There is no evidence to indicate that gray whales utilize ocean currents or follow the same routes as other baleen whales in their migrations. Visual contact with coastal landmarks appear to aid gray whales in successfully accomplishing the 5000-mile migration between summer feeding grounds in the Bering and Chukchi Seas and winter breeding grounds in Mexico.Reconstruction of the migration from all available data shows that most of the American herd breeds and calves in January and February, migrates northward in March, April and May, feeds from June through October, and migrates southward in November and December.

scholarly journals Holocene dynamics in the Bering Strait inflow to the Arctic and the Beaufort Gyre circulation based on sedimentary records from the Chukchi Sea

2017 ◽  
Author(s):  
Masanobu Yamamoto ◽  
Seung-Il Nam ◽  
Leonid Polyak ◽  
Daisuke Kobayashi ◽  
Kenta Suzuki ◽  
...  
Keyword(s):  
Sea Ice ◽  
Chukchi Sea ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Circulation System ◽  
Bering Strait ◽  
The Holocene ◽  
Middle Holocene ◽  
Beaufort Gyre

Abstract. The Beaufort Gyre (BG) and the Bering Strait inflow (BSI) are important elements of the Arctic Ocean circulation system and major controls on the distribution of Arctic sea ice. We report records of the quartz/feldspar and chlorite/illite ratios in three sediment cores from the northern Chukchi Sea providing insights into the long-term dynamics of the BG circulation and the BSI during the Holocene. The quartz/feldspar ratio, a proxy of the BG strength, gradually decreased during the Holocene, suggesting a long-term decline in the BG strength, consistent with orbitally-controlled decrease in summer insolation. We suppose that the BG rotation weakened as a result of increasing stability of sea-ice cover at the margins of the Canada Basin, driven by decreasing insolation. Millennial to multi-centennial variability in the quartz/feldspar ratio (the BG circulation) is consistent with fluctuations in solar irradiance, suggesting that solar activity affected the BG strength on these timescales. The BSI approximated by the chlorite/illite record shows intensified flow from the Bering Sea to the Arctic during the middle Holocene, which is attributed primarily to the effect of an overall weaker Aleutian Low. The middle Holocene intensification of the BSI was associated with decrease in sea ice concentrations and increase in marine production, as indicated by biomarker concentrations, suggesting an influence of the BSI on sea ice distribution and biological production in the Chukchi Sea.

scholarly journals Calcium carbonate saturation in the surface water of the Arctic Ocean: undersaturation in freshwater influenced shelves

2009 ◽  
Vol 6 (3) ◽  
pp. 4963-4991 ◽  
Author(s):  
M. Chierici ◽  
A. Fransson
Keyword(s):  
Calcium Carbonate ◽  
Surface Water ◽  
Cold Water ◽  
Dissolved Inorganic Carbon ◽  
Chukchi Sea ◽  
Total Alkalinity ◽  
The Arctic ◽  
Subsurface Water ◽  
Chukchi Peninsula ◽  
Bering Strait

Abstract. In the summer of 2005, we sampled surface water and measured pH and total alkalinity (AT) underway aboard IB Oden along the Northwest Passage from Cape Farwell (South Greenland) to the Chukchi Sea. We investigated variability of carbonate system parameters, focusing particularly on carbonate concentration [CO32−] and calcium carbonate saturation states, as related to freshwater addition, biological processes and physical upwelling. Measurements on AT, pH at 15°C, salinity (S) and sea surface temperature (SST), were used to calculate total dissolved inorganic carbon (DIC), [CO32−] and saturation of aragonite (ΩAr) and calcite (ΩCa) in the surface water. The same parameters were measured in the water column of the Bering Strait. Some surface waters in the Canadian Arctic Archipelago (CAA) and on the Mackenzie shelf (MS) were found to be undersaturated with respect to aragonite (ΩAr<1). In these areas, surface water was low in AT and DIC (<1500 μmol kg−1) relative to seawater and showed low [CO32−]. The low saturation states were probably due to the effect of dilution due from freshwater addition by sea ice melt (CAA) and river runoff (MS). High AT and DIC and low pH, corresponded with the lowest [CO32−], ΩAr and ΩCa, observed near Cape Bathurst and along the South Chukchi Peninsula. This was linked to physical upwelling of subsurface water with elevated CO2. Highest surface ΩAr and ΩCa of 3.0 and 4.5, respectively, were found on the Chukchi Sea shelf and in the cold water north of Wrangel Island, which is heavily influenced by high CO2 drawdown and lower DIC from intense biological production. In the western Bering Strait, the cold and saline Anadyr Current carries water that is enriched in AT and DIC from enhanced organic matter remineralization, resulting in the lowest ΩAr (~1.2) of the area.

scholarly journals On the circulation, water mass distribution, and nutrient concentrations of the western Chukchi Sea

Ocean Science ◽  
2022 ◽  
Vol 18 (1) ◽  
pp. 29-49
Author(s):  
Jaclyn Clement Kinney ◽  
Karen M. Assmann ◽  
Wieslaw Maslowski ◽  
Göran Björk ◽  
Martin Jakobsson ◽  
...  
Keyword(s):  
Numerical Modelling ◽  
Arctic Ocean ◽  
Dissolved Inorganic Carbon ◽  
Chukchi Sea ◽  
The Arctic ◽  
Sediment Surface ◽  
Nutrient Concentrations ◽  
Bering Strait ◽  
East Siberian Sea ◽  
The Arctic Ocean

Abstract. Substantial amounts of nutrients and carbon enter the Arctic Ocean from the Pacific Ocean through the Bering Strait, distributed over three main pathways. Water with low salinities and nutrient concentrations takes an eastern route along the Alaskan coast, as Alaskan Coastal Water. A central pathway exhibits intermediate salinity and nutrient concentrations, while the most nutrient-rich water enters the Bering Strait on its western side. Towards the Arctic Ocean, the flow of these water masses is subject to strong topographic steering within the Chukchi Sea with volume transport modulated by the wind field. In this contribution, we use data from several sections crossing Herald Canyon collected in 2008 and 2014 together with numerical modelling to investigate the circulation and transport in the western part of the Chukchi Sea. We find that a substantial fraction of water from the Chukchi Sea enters the East Siberian Sea south of Wrangel Island and circulates in an anticyclonic direction around the island. This water then contributes to the high-nutrient waters of Herald Canyon. The bottom of the canyon has the highest nutrient concentrations, likely as a result of addition from the degradation of organic matter at the sediment surface in the East Siberian Sea. The flux of nutrients (nitrate, phosphate, and silicate) and dissolved inorganic carbon in Bering Summer Water and Winter Water is computed by combining hydrographic and nutrient observations with geostrophic transport referenced to lowered acoustic Doppler current profiler (LADCP) and surface drift data. Even if there are some general similarities between the years, there are differences in both the temperature–salinity and nutrient characteristics. To assess these differences, and also to get a wider temporal and spatial view, numerical modelling results are applied. According to model results, high-frequency variability dominates the flow in Herald Canyon. This leads us to conclude that this region needs to be monitored over a longer time frame to deduce the temporal variability and potential trends.

Beach observations of plastic and marine litter along the Northwest Passage

2020 ◽  
Author(s):  
Peter Gijsbers ◽  
Hester Jiskoot
Keyword(s):  
Marine Pollution ◽  
Chukchi Sea ◽  
Canadian Arctic ◽  
The Arctic ◽  
Canadian Arctic Archipelago ◽  
Bering Strait ◽  
Marine Litter ◽  
Northwest Passage ◽  
Distant Early Warning ◽  
Dew Line

&lt;p&gt;Marine litter and microplastics are everywhere. Even the Arctic Ocean, Svalbard and Jan Mayen Island are contaminated as various publications confirm. Little, however, is reported about marine waters and shores of the Canadian Arctic Archipelago. This poster presents the results of a privately funded citizen science observation to scan remote beaches along the Northwest Passage for marine litter pollution.&lt;/p&gt;&lt;p&gt;The observations were conducted while enjoying the 2019 Northwest Passage sailing expedition of the Tecla, a 1915 gaff-ketch herring drifter. The expedition started in Ilulissat, Greenland, on 1 August and ended in Nome, Alaska, on 18 September. After crossing Baffin Bay, the ship continued along Pond Inlet, Navy Board Inlet, Lancaster Sound, Barrow Strait, Peel Sound, Franklin Strait, Rea Strait, Simpson Strait, Queen Maud Gulf, Coronation Gulf, Amundsen Gulf, Beaufort Sea, Chukchi Sea and Bering Strait. The vessel anchored in the settlement harbours of Pond Inlet, Taloyoak, Gjoa Haven, Cambridge Bay and Herschel Island. In addition, Tecla&amp;#8217;s crew made landings at remote beaches on Disko Island (Fortune Bay, Disko Fjord), Beechey Island (Union Bay), Somerset Island (Four Rivers Bay), Boothia Peninsula (Weld Harbour), King William Island (M&amp;#8217;Clintock Bay), Jenny Lind Island, and at Kugluktuk and Tuktoyaktuk Peninsula.&lt;/p&gt;&lt;p&gt;Following the categorization of the OSPAR Guideline for Monitoring Marine Litter on Beaches, litter observations were conducted without penetrating the beach surfaces. Beach stretches scanned varied in length from 100-400 m. No observations were conducted at inhabited settlements or at the abandoned settlements visited on Disko Island (Nipisat) and Beechey Island (Northumberland House).&lt;/p&gt;&lt;p&gt;Observations on the most remote beaches found 2-5 strongly bleached or decayed items in places such as Union Bay, Four Rivers Bay, Weld Harbour, Jenny Lind Island (Queen Maud Gulf side). Landings within 15 km of local settlements (Fortune Bay, Disko Fjord, Kugluktuk, Tuktoyaktuk) or near military activity (Jenny Lind Island, bay side) showed traces of local camping, hunting or fishing activities, resulting in item counts between 7 and 29. At the lee shore spit of M&amp;#8217;Clintock Bay, significant pollution (&gt; 100 items: including outboard engine parts, broken ceramic, glass, clothing, decayed batteries, a crampon and a vinyl record) was found, in contrast to a near-pristine beach on the Simpson Strait side. The litter type and concentration, as well as the remains of a building and shipwrecked fishing vessel indicate that this is an abandoned settlement, possibly related to the construction of the nearby Distant Early Warning Line radar site CAM-2 of Gladman Point. DEW Line sites have long been associated with environmental disturbances.&lt;/p&gt;&lt;p&gt;Given the 197 beach items recorded, it can be concluded that the beaches of the Canadian Arctic Archipelago, which are blocked by sea ice during most of the year, are not pristine. Truly remote places have received marine pollution for decades to centuries. Where (abandoned) settlements are at close range pollution from local activities can be discovered, while ocean currents, wind patterns, ice rafting, distance to river mouths, and flotsam, jetsam and derelict also determine the type and amount of marine litter along the Northwest Passage.&lt;/p&gt;

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