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

Andrea Cappelletti, Paola Picco, Tiziana Peluso

Research output: Contribution to journalArticle

7 Citations (Scopus)

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. Copyright © 2010 Antarctic Science Ltd.
Original languageEnglish
Pages (from-to)319 - 329
Number of pages11
JournalAntarctic Science
Volume22
Issue number3
DOIs
Publication statusPublished - Jan 2010
Externally publishedYes

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Oceanography
  • Ecology, Evolution, Behavior and Systematics
  • Geology

Cite this