The tides and tidal circulation of Todos os Santos Bay, northeast Brazil: a general characterization

Citation
Gc. Lessa et al., The tides and tidal circulation of Todos os Santos Bay, northeast Brazil: a general characterization, AN AC BRASI, 73(2), 2001, pp. 245-261
Citations number
28
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary
Journal title
ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS
ISSN journal
0001-3765 → ACNP
Volume
73
Issue
2
Year of publication
2001
Pages
245 - 261
Database
ISI
SICI code
0001-3765(200106)73:2<245:TTATCO>2.0.ZU;2-S
Abstract
The Todos os Santos Bay, located on northeastern Brazil, is the second larg est coastal bay in the country. after Sao Marcos Bay. The three main draina ge basins convey an average of 120 m(3)/s of freshwater towards the bay, th e majority of it, however, held by a dam in Paraguacu River since 1985. The original average freshwater inflow was two orders of magnitude smaller tha n the estimated tidal discharge through the main bay entrance, and the ocea nographic characteristics of the bay, as indicated by bay salinity measurem ents, are clearly marine. The tides are semi-diurnal, and are amplified up the bay by a factor of 1.5. Shallow water constituents become more importan t as the tide propagates along Paraguacu Channel and Paraguacu River, where they generate time asymmetries that change between spring and neap tides. Currents in the bay are mainly bi-directional, and are stronger during the ebbing tide in most of the bay. Offshore, relatively strong tidal currents appear to be felt in a radius of about 10 km, where they are superimposed o n winds driven currents orientated to the southwest.