Circulation of the Chukchi Sea shelfbreak and slope from moored timeseries

Li, Min; Pickart, Robert S.; Spall, Michael A.; Weingartner, Thomas J.; Lin, Peigen; Moore, G. W. K.; Qi, Yiquan

doi:10.1016/j.pocean.2019.01.002

Cited by 63 publications

(143 citation statements)

References 54 publications

Supporting

Mentioning

127

Contrasting

Order By: Relevance

“…The composite mean plots reveal that the high 228 Ra activities observed near the shelfbreak are associated with cold water moving from west to east. This result, along with the 228 Ra enrichments observed in WW and RWW in the regional T‐S diagram (Figure S7), suggests that 228 Ra‐enriched WW is being transported from the Chukchi Shelf via the Chukchi shelfbreak jet (Corlett & Pickart, ; Li et al, ). The WW advected by the shelfbreak jet likely becomes enriched in 228 Ra during its residence time over the Chukchi shelf (Vieira et al, ).…”

Section: Discussionmentioning

confidence: 89%

“…These general circulation features are shown in Figure a. Some of the water that flows through Herald Canyon travels along the Chukchi shelfbreak from west to east, forming a shelfbreak jet (Corlett & Pickart, ; Li et al, ; Mathis et al, ; Pickart et al, , ). Recently, it was discovered that much of the outflow from Barrow Canyon is steered to the left and forms the westward flowing Chukchi Slope Current, offshore of the shelfbreak jet (Corlett & Pickart, ; Li et al, ; Spall et al, ).…”

Section: Introductionmentioning

confidence: 99%

“…Some of the water that flows through Herald Canyon travels along the Chukchi shelfbreak from west to east, forming a shelfbreak jet (Corlett & Pickart, ; Li et al, ; Mathis et al, ; Pickart et al, , ). Recently, it was discovered that much of the outflow from Barrow Canyon is steered to the left and forms the westward flowing Chukchi Slope Current, offshore of the shelfbreak jet (Corlett & Pickart, ; Li et al, ; Spall et al, ). Eddies transporting shelf‐influenced waters into the Canada Basin are also common (Mathis et al, ; Muench et al, ; Pickart et al, ; Spall et al, ; Timmermans et al, ).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Shelf‐Basin Interactions and Water Mass Residence Times in the Western Arctic Ocean: Insights Provided by Radium Isotopes

et al. 2019

Self Cite

View full text Add to dashboard Cite

Radium isotopes are produced through the decay of thorium in sediments and are soluble in seawater; thus, they are useful for tracing ocean boundary‐derived inputs to the ocean. Here we apply radium isotopes to study continental inputs and water residence times in the Arctic Ocean, where land‐ocean interactions are currently changing in response to rising air and sea temperatures. We present the distributions of radium isotopes measured on the 2015 U.S. GEOTRACES transect in the Western Arctic Ocean and combine this data set with historical radium observations in the Chukchi Sea and Canada Basin. The highest activities of radium‐228 were observed in the Transpolar Drift and the Chukchi shelfbreak jet, signaling that these currents are heavily influenced by interactions with shelf sediments. The ventilation of the halocline with respect to inputs from the Chukchi shelf occurs on time scales of ≤19–23 years. Intermediate water ventilation time scales for the Makarov and Canada Basins were determined to be ~20 and >30 years, respectively, while deep water residence times in these basins were on the order of centuries. The radium distributions and residence times described in this study serve as a baseline for future studies investigating the impacts of climate change on the Arctic Ocean.

show abstract

Section: Discussionmentioning

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Shelf‐Basin Interactions and Water Mass Residence Times in the Western Arctic Ocean: Insights Provided by Radium Isotopes

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…This is supported by mooring measurements (Weingartner, Fang, et al, ), shipboard measurements (Pickart et al, ), drifter tracks (Stabeno et al, ), and surface radar measurements (Fang et al, ). Upon exiting Barrow Canyon, the Pacific water forms the eastward‐flowing Beaufort Shelfbreak Jet (Pickart, ) and westward‐flowing Chukchi Slope Current (Corlett & Pickart, ; Li et al, ; Spall et al, ; Stabeno et al, ). The water subsequently enters the Canada Basin via shelf‐basin interactions, for example, eddies (Pickart et al, ), upwelling (Lin, Pickart, Moore, et al, ), and downwelling (Dmitrenko et al, ).…”

Section: Introductionmentioning

confidence: 99%

Water Mass Evolution and Circulation of the Northeastern Chukchi Sea in Summer: Implications for Nutrient Distributions

et al. 2019

Self Cite

View full text Add to dashboard Cite

Synoptic and historical shipboard data, spanning the period 1981–2017, are used to investigate the seasonal evolution of water masses on the northeastern Chukchi shelf and quantify the circulation patterns and their impact on nutrient distributions. We find that Alaskan coastal water extends to Barrow Canyon along the coastal pathway, with peak presence in September, while the Pacific Winter Water (WW) continually drains off the shelf through the summer. The depth‐averaged circulation under light winds is characterized by a strong Alaskan Coastal Current (ACC) and northward flow through Central Channel. A portion of the Central Channel flow recirculates anticyclonically to join the ACC, while the remainder progresses northeastward to Hanna Shoal where it bifurcates around both sides of the shoal. All of the branches converge southeast of the shoal and eventually join the ACC. The wind‐forced response has two regimes: In the coastal region the circulation depends on wind direction, while on the interior shelf the circulation is sensitive to wind stress curl. In the most common wind‐forced state—northeasterly winds and anticyclonic wind stress curl—the ACC reverses, the Central Channel flow penetrates farther north, and there is mass exchange between the interior and coastal regions. In September and October, the region southeast of Hanna Shoal is characterized by elevated amounts of WW, a shallower pycnocline, and higher concentrations of nitrate. Sustained late‐season phytoplankton growth spurred by this pooling of nutrients could result in enhanced vertical export of carbon to the seafloor, contributing to the maintenance of benthic hotspots in this region.

show abstract

“…Schematic circulation of the Chukchi Sea (after Corlett & Pickart, and Li et al, ) and geographical place names.…”

Section: Introductionmentioning

confidence: 99%

Characteristics and Transformation of Pacific Winter Water on the Chukchi Sea Shelf in Late Spring

et al. 2019

Self Cite

View full text Add to dashboard Cite

Data from a late spring survey of the northeast Chukchi Sea are used to investigate various aspects of newly ventilated winter water (NVWW). More than 96% of the water sampled on the shelf was NVWW, the saltiest (densest) of which tended to be in the main flow pathways on the shelf. Nearly all of the hydrographic profiles on the shelf displayed a two‐layer structure, with a surface mixed layer and bottom boundary layer separated by a weak density interface (on the order of 0.02 kg/m3). Using a polynya model to drive a one‐dimensional mixing model, it was demonstrated that, on average, the profiles would become completely homogenized within 14–25 hr when subjected to the March and April heat fluxes. A subset of the profiles would become homogenized when subjected to the May heat fluxes. Since the study domain contained numerous leads within the pack ice—many of them refreezing—and since some of the measured profiles were vertically uniform in density, this suggests that NVWW is formed throughout the Chukchi shelf via convection within small openings in the ice. This is consistent with the result that the salinity signals of the NVWW along the central shelf pathway cannot be explained solely by advection from Bering Strait or via modification within large polynyas. The local convection would be expected to stir nutrients into the water column from the sediments, which explains the high nitrate concentrations observed throughout the shelf. This provides a favorable initial condition for phytoplankton growth on the Chukchi shelf.

show abstract

Circulation of the Chukchi Sea shelfbreak and slope from moored timeseries

Cited by 63 publications

References 54 publications

Shelf‐Basin Interactions and Water Mass Residence Times in the Western Arctic Ocean: Insights Provided by Radium Isotopes

Shelf‐Basin Interactions and Water Mass Residence Times in the Western Arctic Ocean: Insights Provided by Radium Isotopes

Water Mass Evolution and Circulation of the Northeastern Chukchi Sea in Summer: Implications for Nutrient Distributions

Characteristics and Transformation of Pacific Winter Water on the Chukchi Sea Shelf in Late Spring

Contact Info

Product

Resources

About