On the nature of wind-forced upwelling in Barrow Canyon

Pisareva, Maria N.; Pickart, Robert S.; Lin, Peigen; Fratantoni, Paula S.; Weingartner, Thomas J.

doi:10.1016/j.dsr2.2019.02.002

Cited by 40 publications

(55 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Not surprisingly, the northeasterly wind reverses the ACC relative to the background state (Figure a). This is in line with previous studies using cruise measurements, mooring, and high‐frequency radar data (Aagaard & Roach, ; Fang et al, ; Okkonen et al, ; Pisareva et al, ). It is the result of Ekman setup due to coastal upwelling driven by the along‐coast winds (see Pickart et al, ).…”

Section: Circulation On the Northeastern Chukchi Shelfsupporting

confidence: 92%

“…This is consistent with the surface velocity measurements of Fang et al (2017), which suggest that the ACC can be reversed when northeasterly winds exceed 6 m s −1 . A similar threshold for flow reversal is found in Barrow Canyon (Itoh et al, 2015;Pisareva et al, 2019;.…”

Section: Introductionsupporting

confidence: 75%

“…At times the surface layer of the Chukchi Sea contains a freshwater mass deriving from ice melt and/or river runoff (referred to here as MWR). Finally, water from the Atlantic layer in the Canada Basin is occasionally upwelled onto the shelf via Barrow Canyon (e.g., Ladd et al, ; Pisareva et al, ; Weingartner, Potter, et al, ) and Herald Canyon (Pickart et al, ).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

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

Section: Circulation On the Northeastern Chukchi Shelfsupporting

confidence: 92%

Section: Introductionsupporting

confidence: 75%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

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

show abstract

“…Periodically, this warm and salty water is upwelled into Barrow Canyon in the east (e.g. Aagaard & Roach, 1990;Pisareva et al, 2019) and Herald Canyon in the west (Pickart et al, 2010). Under certain circumstances, the AW can penetrate far onto the shelf (Bourke & Paquette, 1976;Ladd et al, 2016).…”

Section: Journal Of Geophysical Research: Oceansmentioning

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

“…The upwelling and shifting the front are synoptic events (e.g., Pisareva et al., ), and the presence of AW is typically associated with southwestward winds and currents (Ladd et al., ). The winds in DJF 2016–2017 are northeastward, and the synoptic events are unlikely to sustain over 3 months to shift the DJF mean temperature by 0.5 °C from the climatology.…”

Section: Discussionmentioning

confidence: 99%

The Warming of the Chukchi Slope Through the Barrow Canyon Outflow in the 2016–2017 Winter

et al. 2019

View full text Add to dashboard Cite

The shallow Chukchi Sea is a gateway to the Arctic Ocean for Pacific‐origin waters. While a substantial portion of the Pacific‐origin waters flows through Barrow Canyon in the northeast corner of the Chukchi Sea, little is known on the hydrography of the surrounding regions in winter. We present profiles of wintertime hydrography on the Chukchi slope from an autonomous profiling instrument and mooring records in Barrow Canyon. The central and western sectors of Barrow Canyon in December 2016 to February 2017 were anomalously warm (∼0.5 °C warmer than the climatology) with the flow orienting toward the Arctic Ocean. Unlike the summertime warming near the surface, the warm outflow has a temperature maximum at 80 dbar, and this outflow modifies the water mass properties on the Chukchi slope 70 km north of the canyon. Based on our Barrow Canyon mooring records starting in 2002, this is the first time that such warming is recorded on the outflow in winter. We discuss that this is due to the combination of the Barrow Canyon outflow favorable wind pattern and warming in the southern Chukchi Sea (the Gulf of Alaska and the Bering Sea) before the winter.

show abstract

On the nature of wind-forced upwelling in Barrow Canyon

Cited by 40 publications

References 51 publications

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

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

The Warming of the Chukchi Slope Through the Barrow Canyon Outflow in the 2016–2017 Winter

Contact Info

Product

Resources

About