Preliminary analyses on the use of drift measurements of a buoy in the study of shelf currents are
presented. The equipment was moored at Santa Catarina Shelf in Southern Brazil. The drift was measured by means
of a GPS which provided buoy's geographical coordinates on an hourly basis. The data was decomposed in
meridional and zonal position components and along with wind and sea level data, covered a period of 203 days from
late summer (March 21 ) to late spring (October 11 ) of 2002. Statistical comparison between mean sea level (msl)
and the meridional buoy positioning displayed very high correlation (R =0.83) with a 3 h delay in relation to msl.
The best correlation between meridional wind and buoy's drift was attained at 10 h time lag (R =0.63). Sea level
analysis characterizes the tide as mixed, mainly semidiurnal. Diurnal and Semi-Diurnal bands accounted for 63.6%
of energy spectra in comparison to 36.4% on the Meteorological-forcing band. Low frequency signal in
Meteorological band were clearly dominant in the buoy's meridional series, accounting for 90% of energy spectra.
The buoy mooring system seems to work as a very useful indicator of the sense of geostrophic currents over the shelf,
which seems to respond to both regional as well remote wind forcing
