Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-27T09:03:55.278Z Has data issue: false hasContentIssue false

Upper ocean layer dynamics and response to atmospheric forcing in the Terra Nova Bay polynya, Antarctica

Published online by Cambridge University Press:  16 March 2010

Andrea Cappelletti
Affiliation:
ENEA, Via V. Viviani 23, Pisa, Italy
Paola Picco*
Affiliation:
ENEA, Centro Ricerche Ambiente Marino, cp 224, 19100 La Spezia, Italy
Tiziana Peluso
Affiliation:
CNR ISMAR, Forte S. Teresa, 19125 Pozzuolo di Lerici, Italy
*
*Corresponding author: paola.picco@enea.it

Abstract

A one-year time series of Acoustic Doppler Current Profiler (ADCP) data was collected in Terra Nova Bay (TNB) polynya (Ross Sea, Antarctica) during 2000. Together with Automatic Weather Station (AWS) Eneide meteorological data and Special Sensor Microwave Imager (SSM/I) ice concentration data, ADCP data were analysed to investigate upper layer dynamics and variability due to atmospheric forcing. Empirical Orthogonal Function (EOF) analysis was performed to separate the surface variability caused by local forcing from the large-scale circulation component. In particular, the first mode represented the barotropic circulation while the second the stronger surface currents. The decrease in shelf water density from melting sea ice resulted in an off-shore density gradient producing a southern shift in the circulation. This result proved to be consistent with the in situ data acquired during February–April at 120 m depth. The observed variability of the surface currents was assessed with respect to the thermal wind equation and the steady Ekman model. Strong katabatic winds shifted the surface currents eastward with respect to the general north-eastern circulation. The wind stress acted as a relevant forcing for the surface large-scale circulation in TNB, but had negligible effects on the vertically integrated transport.

Type
Physical Science
Copyright
Copyright © Antarctic Science Ltd 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Assmann, K.M.Timmermann, R. 2005. Variability of dense water formation in the Ross Sea. Ocean Dynamics, 55, 6887.CrossRefGoogle Scholar
Assmann, K., Hellmer, H.H.Beckmann, A. 2003. Seasonal variation in circulation and water mass distribution on the Ross Sea continental shelf. Antarctic Science, 15, 311.CrossRefGoogle Scholar
Bergamasco, A.Carniel, S. 2000. Sensitivity analysis of a robust diagnostic general circulation model of the Ross Sea. Journal of Marine System, 27, 336.CrossRefGoogle Scholar
Bromwich, D.H.Kurtz, D.D. 1984. Katabatic wind forcing of the Terra Nova Bay polynya. Journal of Geophysical Research, 89, 35613572.CrossRefGoogle Scholar
Budillon, G.Spezie, G. 2000. Thermohaline structure and variability in the Terra Nova Bay polynya, Ross Sea. Antarctic Science, 12, 493508.CrossRefGoogle Scholar
Buffoni, G., Cappelletti, A.Picco, P. 2002. An investigation of thermohaline circulation in Terra Nova Bay polynya. Antarctic Science, 14, 8392.CrossRefGoogle Scholar
Carmack, E.C. 1977. Water characteristics of the Southern Ocean south of the polar front. In Angel, M.,ed. A voyage of Discovery: George Deacon 70th anniversary volume. Oxford: Pergamon Press, 1542.Google Scholar
Cavalieri, D.C., Parkinson, C., Gloersen, P.Zwally, H.J. 1996. updated 2008. Sea-ice concentration from Nimbus-7 SMMR and DMSP SSM/I passive microwave data. Boulder, CO: National Snow and Ice Data Center. Digital Media.Google Scholar
Comiso, J.C., Maynard, N.G., Smith, W.O.Sullivan, C.W. 1990. Satellite ocean colour studies of Antarctic sea-ice edges in summer and autumn. Journal of Geophysical Research, 95, 94819496.CrossRefGoogle Scholar
Commodari, V.Pierini, S. 1999. A wind and boundary driven circulation model of the Ross Sea. In Spezie, G.&Manzella, G.M.R.,eds. Physical oceanography of the Ross Ice Shelf. Milan: Springer, 135144.Google Scholar
Davolio, S.Buzzi, A. 2002. Mechanism of Antarctic katabatic currents near Terra Nova Bay. Tellus, 54 A, 187204.CrossRefGoogle Scholar
Gallée, H. 1997. Air-sea interaction of Terra Nova Bay during winter: simulation with a coupled atmosphere-polynya model. Journal of Geophysical Research, 102, 13 83513 849.CrossRefGoogle Scholar
Gill, A.E. 1982. Atmosphere-ocean dynamics. New York: Academic Press, 662 pp.Google Scholar
Gonella, J. 1972. A rotary-component method for analyzing meteorological and oceanographic vector time series. Deep Sea Research, 19, 833846.Google Scholar
Gordon, A.L., Padman, L.Bergamasco, A. 2009. Southern Ocean shelf slope exchange. Deep Sea Research II, 56, 13.CrossRefGoogle Scholar
Hellermann, S.Rosenstein, M. 1983. Normal monthly wind stress over the world ocean with error estimates. Journal of Physical Oceanography, 13, 10931104.2.0.CO;2>CrossRefGoogle Scholar
Hyatt, J., Visbeck, M., Beardsley, R.C.Owens, W.B. 2008. Estimating sea-ice coverage, draft, and velocity in Marguerite Bay (Antarctica) using a subsurface moored upward-looking Acoustic Doppler Current Profiler (ADCP). Deep Sea Research II, 55, 351364.CrossRefGoogle Scholar
Jacobs, S.S., Amos, A.F.Bruchhausen, P.M. 1970. Ross Sea oceanography and Antarctic bottom water formation. Deep Sea Research, 17, 935962.Google Scholar
Jacobs, S.S. 2004. Bottom water production and its links with the thermohaline circulation. Antarctic Science, 16, 427437.CrossRefGoogle Scholar
Jacobs, S.S., Fairbanks, G.R.Horibe, Y. 1985. Origin and evolution of water masses near the Antarctic continental margin from H2180/H2160 ratio in sea water. Antarctic Research Series, 43, 5986.CrossRefGoogle Scholar
Johnson, E.S.van Woert, M.L. 2006. Tidal currents of the Ross Sea and their time stability. Antarctic Science, 18, 141154.CrossRefGoogle Scholar
Kundu, P.K. 1976. Ekman veering observed near the ocean bottom. Journal of Physical Oceanography, 6, 238242.2.0.CO;2>CrossRefGoogle Scholar
Kurtz, D.D.Bromwich, D.H. 1985. A recurring atmospherically-forced polynya in Terra Nova Bay. Antarctic Research Series, 43, 177201.CrossRefGoogle Scholar
Large, W.G.Pond, S. 1981. Open ocean momentum flux measurements in moderate to strong winds. Journal of Physical Oceanography, 11, 324481.2.0.CO;2>CrossRefGoogle Scholar
Liu, A.K., Martin, S.M.Kwok, R. 1997. Tracking of ice edge and ice floes by wavelet analysis of SAR images. Journal of Atmospheric and Oceanic Technology, 14, 11871198.2.0.CO;2>CrossRefGoogle Scholar
Locarnini, R.A. 1994. Water masses and circulation in the Ross Gyre and environs. PhD thesis, Texas A&M University, 87 pp. [Unpublished.]Google Scholar
Manzella, G.M.R., Meloni, R.Picco, P. 1999. Current temperature and salinity observations in Terra Nova Bay polynya. In Manzella, G.M.R.&Spezie G., eds. Oceanography of the Ross Sea. Berlin: Springer, 165173.CrossRefGoogle Scholar
Martin, S., Drucker, R.S.Kwok, R. 2007. The area and ice production of the western and central Ross Sea polynyas, 1992–2002, and their relation to the B-15 and C-19 iceberg events of 2000 and 2002. Journal of Marine Systems, 68, 201214.CrossRefGoogle Scholar
Orsi, A.H.Wiederwohl, C.L. 2009. A recount of Ross Sea waters. Deep Sea Research II, 56, 778795.CrossRefGoogle Scholar
Pedlosky, J. 1979. Geophysical fluid dynamics. New York: Springer, 432 pp.CrossRefGoogle Scholar
Petrelli, P., Bindoff, N.L.Bergamasco, A. 2008. The sea-ice dynamics of Terra Nova Bay and Ross Sea Ice Shelf polynyas during a spring and winter simulation. Journal of Geophysical Research, 113, 116.CrossRefGoogle Scholar
Pillsbury, R.D.Jacobs, S.S. 1985. Preliminary observation of long-term current meter moorings near the Ross Ice Shelf, Antarctica. Antarctic Research Series, 43, 87107.CrossRefGoogle Scholar
PNRA. 1995. Rapporto sulla Campagna Antartica Estate Australe 1994–95, X Spedizione. Roma: Progetto Antartide, ANT 95/02, 238 pp.Google Scholar
PNRA. 2001. Rapporto sulla Campagna Antartica Estate Australe 2000–2001, XVI Spedizione. Roma: Progetto Antartide, ANT 01/01, 259 pp.Google Scholar
Renfrew, A.I.Anderson, S.P. 2002. The surface climatology of an ordinary katabatic wind regime in Coats Land, Antarctica. Tellus, 54A, 463484.CrossRefGoogle Scholar
Shcherbina, A.Y., Rudnick, D.L.Talley, L.D. 2005. Ice-draft profiling from bottom-mounted ADCP data. Journal of Atmospheric and Oceanic Technology, 22, 12491266.CrossRefGoogle Scholar
Spezie, G.Manzella, G.M.R. 1999. Preface. In Manzella, G.M.R.&Spezie, G., eds. Oceanography of the Ross Sea. Berlin: Springer, viiix.CrossRefGoogle Scholar
Timmermann, R.Beckmann, A. 1999. Parameterization of vertical mixing in the Weddell Sea. Ocean Modelling, 6, 83100.CrossRefGoogle Scholar
Van Woert, M.L. 1999. Wintertime dynamics of the Terra Nova Bay polynya. Journal of Geophysical Research, 104, 77537769.CrossRefGoogle Scholar
Visbeck, M.Fisher, J. 1995. Sea surface conditions remotely sensed by upward-looking ADCPs. Journal of Atmospheric and Oceanic Technology, 12, 141149.2.0.CO;2>CrossRefGoogle Scholar
Williams, G.D., Bindoff, N.L., Marsland, S.J.Rintoul, S.R. 2008. Formation and export of dense shelf water from the Adélie Depression, East Antarctica. Journal of Geophysical Research, 113, 112.CrossRefGoogle Scholar