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

AbstractA 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.

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Satellite observations of upper-ocean currents in Terra Nova Bay, Antarctica

Annals of Glaciology ◽

10.3189/172756401781818879 ◽

2001 ◽

Vol 33 ◽

pp. 407-412 ◽

Cited By ~ 11

Author(s):

Michael L. van Woert ◽

Walter N. Meier ◽

Cheng-Zhi Zou ◽

Andy Archer ◽

Andrea Pellegrini ◽

...

Keyword(s):

Cross Correlation ◽

Ross Sea ◽

Surface Currents ◽

Ocean Variability ◽

Terra Nova Bay ◽

Correlation Algorithm ◽

Defense Meteorological Satellite Program ◽

Oceanic Response ◽

Terra Nova ◽

Meteorological Satellite

AbstractShip and iceberg drifts, along with data from modern satellite-tracked drifting buoys, portray generally northward flow in the southwest Ross Sea. Less is known, however, about the ocean variability in this region. Here we use Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) imagery to describe a cyclonically rotating gyre in Terra Nova Bay, Antarctica (75° S, 165° E). The image sequence is taken from an exceptionally clear, calm period during winter 1998. Surface currents, derived from tracking drifting ice with a maximum cross-correlation algorithm, were found to be ∼ 20 to 30 cm s−1 Based on scaling arguments, the observed currents appear to be best explained as an oceanic response to a rapidly changing, offshore, katabatic windjet.

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Salinity response to atmospheric forcing of the Terra Nova Bay polynya, Antarctica

Antarctic Science ◽

10.1017/s0954102021000146 ◽

2021 ◽

pp. 1-14

Author(s):

Deborah A. Le Bel ◽

Christopher J. Zappa ◽

Giorgio Budillon ◽

Arnold L. Gordon

Keyword(s):

Ross Sea ◽

Open Water ◽

Heat Fluxes ◽

Ice Formation ◽

Atmospheric Forcing ◽

Surface Heat Fluxes ◽

Water Fraction ◽

Salinity Response ◽

Terra Nova Bay ◽

Terra Nova

Abstract The density and salinity of High Salinity Shelf Water, a key component of Antarctic Bottom Water emanating from the Ross Sea, are intensified by brine rejection induced by ice formation within the Terra Nova Bay (TNB) polynya. Ocean mooring data from 2007, meteorological observations from automatic weather stations and a satellite-derived history of the opening of TNB polynya delineate variability in water column salinity linked to atmospheric forcing, with a period on the order of 10 days. Lagged correlation analysis indicates that on average salinity response lags the polynya opening by 2 days and the wind forcing by 5 days. We find stronger correlations of salinity with the wind during March through May and with the polynya open-water fraction during June through October, with decreasing lags in the latter period. A one-dimensional mixed-layer model incorporating thermodynamic ice formation captures the oscillations in salinity. A process study shows that the variability in the polynya open-water fraction governs the final salinity attained by the model as well as the salinity cycling. Variability in surface heat fluxes modulates that effect. Our work suggests that there is a more complex relationship between salinity, the polynya open-water fraction, and atmospheric forcing than previously suggested.

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Biogeochemical cycling of Pb in the coastal marine environment at Terra Nova Bay, Ross Sea

Antarctic Science ◽

10.1017/s0954102003001524 ◽

2003 ◽

Vol 15 (4) ◽

pp. 425-432 ◽

Cited By ~ 12

Author(s):

S. DALLA RIVA ◽

M.L. ABELMOSCHI ◽

M. CHIANTORE ◽

M. GROTTI ◽

E. MAGI ◽

...

Keyword(s):

Ross Sea ◽

Ice Core ◽

Concentration Data ◽

Odontaster Validus ◽

Terra Nova Bay ◽

Coastal Marine ◽

Pack Ice ◽

Laternula Elliptica ◽

Trematomus Bernacchii ◽

Terra Nova

The biogeochemical cycle of lead in the marine coastal environment of Terra Nova Bay has been investigated by determining the lead concentration in a large number of matrices: marine sediments, pack ice, snow, seawater, marine microlayer, aerosol and eight species of marine organisms (the bivalve molluscs Adamussium colbecki and Laternula elliptica, the seastar Odontaster validus, the sea urchin Sterechinus neumayeri, the fish Trematomus bernacchii, the seaweeds Iridaea cordata and Phyllophora antarctica, and the nemertine worm Parborlasia corrugatus). The study of solid speciation of sediment showed that the site is not influenced by human activity and is hence suitable to examine natural processes. The concentration values found in the suspended paniculate matter (SPM) of pack ice core, aerosol, marine microlayer and seawater as well as the particulate morphology, investigated by SEM, seem to support the hypothesis that particulate lead is transferred from the atmosphere to the water column through three different mechanisms: (i) release of SPM from the pack ice during its melting, (ii) input from the continental land through wet deposition, (iii) transport by aerosol and marine microlayer. Concentration data both in the whole organism and in some target organs indicated two suitable biomonitor organisms: the bivalva Laternula elliptica (particularly its digestive gland) and the fish Trematomus bernacchii (particularly its bones).

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Particulate organic matter release below melting sea ice (Terra Nova Bay, Ross Sea, Antarctica): Possible relationships with zooplankton

Journal of Marine Systems ◽

10.1016/j.jmarsys.2021.103510 ◽

2021 ◽

pp. 103510

Author(s):

Alessandro Cau ◽

Claudia Ennas ◽

Davide Moccia ◽

Olga Mangoni ◽

Francesco Bolinesi ◽

...

Keyword(s):

Organic Matter ◽

Sea Ice ◽

Particulate Organic Matter ◽

Ross Sea ◽

Terra Nova Bay ◽

Terra Nova

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A comparison between polynya area and associated ice production with mooring-based measurements of temperature, salinity and currents in the southwestern Ross Sea, Antarctica

Annals of Glaciology ◽

10.3189/172756411795931705 ◽

2011 ◽

Vol 52 (57) ◽

pp. 291-300 ◽

Cited By ~ 3

Author(s):

Stefan Kern ◽

Stefano Aliani

Keyword(s):

Ross Sea ◽

Time Lag ◽

Ice Formation ◽

Terra Nova Bay ◽

In Situ Observations ◽

Satellite Microwave ◽

Terra Nova ◽

Ice Production ◽

The Impact

AbstractWintertime (April–September) area estimates of the Terra Nova Bay polynya (TNBP), Antarctica, based on satellite microwave radiometry are compared with in situ observations of water salinity, temperature and currents at a mooring in Terra Nova Bay in 1996 and 1997. In 1996, polynya area anomalies and associated anomalies in polynya ice production are significantly correlated with salinity anomalies at the mooring. Salinity anomalies lag area and/or ice production anomalies by about 3 days. Up to 50% of the variability in the salinity at the mooring position can be explained by area and/or ice production anomalies in the TNBP for April–September 1996. This value increases to about 70% when considering shorter periods like April–June or May–July, but reduces to 30% later, for example July–September, together with a slight increase in time lag. In 1997, correlations are smaller, less significant and occur at a different time lag. Analysis of ocean currents at the mooring suggests that in 1996 conditions were more favourable than in 1997 for observing the impact of descending plumes of salt-enriched water formed in the polynya during ice formation on the water masses at the mooring depth.

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Diesel oil and PCB-degrading psychrotrophic bacteria isolated from Antarctic seawaters (Terra Nova Bay, Ross Sea)

Polar Research ◽

10.3402/polar.v23i2.6275 ◽

2004 ◽

Vol 23 (2) ◽

pp. 141-146 ◽

Cited By ~ 9

Author(s):

Maria De Domenico ◽

Angelina Lo Giudice ◽

Luigi Michaud ◽

Marcello Saitta ◽

Vivia Bruni

Keyword(s):

Ross Sea ◽

Diesel Oil ◽

Psychrotrophic Bacteria ◽

Terra Nova Bay ◽

Terra Nova

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Summer Epiphytic Diatoms from Terra Nova Bay and Cape Evans (Ross Sea, Antarctica) - A Synthesis and Final Conclusions

PLoS ONE ◽

10.1371/journal.pone.0153254 ◽

2016 ◽

Vol 11 (4) ◽

pp. e0153254 ◽

Cited By ~ 15

Author(s):

Roksana Majewska ◽

Peter Convey ◽

Mario De Stefano

Keyword(s):

Ross Sea ◽

Epiphytic Diatoms ◽

Terra Nova Bay ◽

Terra Nova

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Significance of selected halocarbons monitoring in air samples collected in the Terra Nova Bay region (northern Victoria Land, Antarctica)

Antarctic Science ◽

10.1017/s0954102099000322 ◽

1999 ◽

Vol 11 (2) ◽

pp. 261-264 ◽

Cited By ~ 3

Author(s):

Filippo Mangani ◽

Michela Maione ◽

Luciano Lattanzi

Keyword(s):

Ross Sea ◽

Atmospheric Concentration ◽

Air Samples ◽

Terra Nova Bay ◽

Victoria Land ◽

Rate Of Increase ◽

Terra Nova ◽

Concentration Levels

CCl3F (or CFC-11) and CCl2F2 (or CFC-12) were determined in air samples collected, during subsequent summer Antarctic campaigns, in different sampling sites in the Ross Sea Region. The samples were analysed by GC-ECD after enrichment. Data obtained since 1988–89 were plotted to observe the trend of CFCs atmospheric concentration levels. A decrease in the rate of increase of CFC-12 concentration was observed, whilst the concentration of CFC-11 was actually seen to be decreasing.

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