Tidal and Low-Frequency Currents Near the Shelf-Break: Northeastern Coast of Brazil

Autor: Sérgio Romano Signorini, Luiz Bruner de Miranda
Rok vydání: 1983
Předmět:
Zdroj: Journal of Physical Oceanography. 13:2107-2115
ISSN: 1520-0485
0022-3670
DOI: 10.1175/1520-0485(1983)013<2107:talfcn>2.0.co;2
Popis: Time series of a 40-day (13 March-23 April 1979) wind and current observational experiment are analyzed. The wind data originated from the Fortaleza Airport Weather Station (Ceara, Brazil), and the current meter data originated concurrently from moorings deployed on the shelf break, 40 km offshore. The meters were placed at 8, 16 and 36 m. Strong tidal currents were observed, with a range of 30 to 40 cm s−1 during the equinoctial spring tide period. The analytical model of Battisti and Clarke was applied to the prediction of the diurnal and semidiurnal tidal currents at the mooring site. Good overall agreement with the data was obtained. The wind record spectral and harmonic analysis indicated the presence of a relatively strong diurnal breeze (amplitude of 2.2 m s−1) and a less energetic semidiurnal breeze (amplitude of 0.9 m s−1). A low frequency coastal current flowing northwestward with a near surface mean speed of 16 cm s−1 was also observed. Alongshelf wind and current are highly coherent i...
Databáze: OpenAIRE