The influence of an Antarctic glacier tongue on near-field o
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TitleThe influence of an Antarctic glacier tongue on near-field ocean circulation and mixingAbstractIn situ measurements of flow and stratification in the vicinity of the Erebus Glacier Tongue, a 12 km long floating Antarctic glacier, show the significant influence of the glacier. Three ADCPs (75, 300, and 600 kHz) were deployed close (<50 m) to the sidewall of the glacier in order to capture near-field flow distortion. Scalar (temperature and conductivity) and shear microstructure profiling captured small-scale vertical variability. Flow magnitudes exceeded 0.3 m s-1 through a combination of tidal flow (8 cm s-1) and a background/residual flow (4-10 cm s-1) flowing to the NW. Turbulence was dominated by deeper mixing during spring tide, likely indicative of the role of bathymetric variation which locally forms an obstacle as great as the glacier. During the neap tide, near-surface mixing was as energetic as that seen in the spring tide, suggesting the presence of buoyancy-driven near-surface flows. Estimates of integrated dissipation rate suggest that these floating extensions of the Antarctic ice sheet alter energy budgets through enhanced dissipation, and thus influence coastal near-surface circulation. Key Points A blocking layer is generated by the floating glacier Tidal rectification or substantial residual flow results in tidal asymmetry Upper water column mixing is at least as strong during neap tides as spring Copyright 2014. American Geophysical Union. All Rights Reserved.AcknowledgementsThe authors wish to thank Brett Grant, Martin Doble, Jim Stockel, and the staff of Scott Base for their support in the field. Patricia Langhorne, Craig Stewart, Natalie Robinson, Bernard Laval, Robin Robertson, and Michael Williams are thanked for their valuable discussions of the analysis. Andre w Hamilton is thanked for his coordination of the Canadian research component and discussions with Air New Zealand. Joseph Wright assisted in the collection of the GPS data. Satellite imagery is courtesy of NASA. Two anonymous Reviewers are thanked for their comments on an earlier version of this manuscript. Metadata are lodged with Antarctica New Zealand.The work was funded by The New Zealand Royal Society administered Marsden Fund, and US NSF support to Stanton and McPhee. Logistic support was provided by Antarctica New Zealand and travel funding from Air New Zealand.Funding DetailsNSF, National Science Foundation
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1st AuthorStevens, C.AuthorStevens, C.McPhee, M.Forrest, A.Leonard, G.Stanton, T.Haskell, T.Year2014JournalJournal of Geophysical Research: OceansVolume119Number4Pages2344-2362DOI10.1002/2013JC009070URLhttps://www.scopus.com/inward/recor.....8f890859c06acc7ea6476dbd5KeywordsSupercoolingTurbulence, Antarctic ice sheetsAntarcticablockingIn-situ measurementNear-surface circulationOcean circulationOcean mixingUpper water column, Mixing, bathymetric surveyenergy budgetglacier flowice sheetmicrostructuremixingstratificationsupercoolingturbulence, AntarcticaEast AntarcticaErebus Bay, rank5Author KeywordsAntarcticablockingglacier tongueocean mixingsupercoolingturbulence
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TypeArticleCitationStevens, C., McPhee, M., Forrest, A., Leonard, G., Stanton, T. and Haskell, T. (2014). The influence of an Antarctic glacier tongue on near-field ocean circulation and mixing. Journal of Geophysical Research: Oceans, 119(4): 2344-2362IdentifierStevens2014Relevancerank5
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Haskell, T., The influence of an Antarctic glacier tongue on near-field o, [Stevens2014]. Antarctica NZ, accessed 13/02/2025, https://adam.antarcticanz.govt.nz/nodes/view/63779, 10.1002/2013JC009070