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Numerical simulations of potential oil spills near Fernando de Noronha archipelago
Published in C. Guedes Soares, T.A. Santos, Trends in Maritime Technology and Engineering Volume 2, 2022
P.G.S.C. Siqueira, J.A.M. Silva, M.L.B. Gois, H.O. Duarte, M.C. Moura, M.A. Silva, M.C. Araújo
The FNA is in a warm tropical region. The air temperature on average is 25°C and a well-defined dry season between August and February, and a rainy season between March and July, averaging 1400 mm rainfall (Serafini and França, 2010). The prevailing winds are the southeast trade winds. The greater intensity occurs between July and August (Tchamabi et al., 2017). The highest sea surface temperatures (SST) occur between March and June, typically exceeding 28°C due to the occurrence of the southwestern tropical Atlantic warm pool (Cintra et al., 2015) and the lowest between August and November (SST ~26.6°C) (Silva et al., 2009; Hounsou-Gbo et al., 2015; Tchamabi et al., 2017). On the ocean surface, the central branch of the South Equatorial Current (cSEC) flows westward until it reaches the North Brazil Current (NBC) near the coast (Stramma and Schott, 1999; Lumpkin and Garzoli, 2005). The cSEC is stronger between March and July, and weaker between August and February (Lumpkin and Johnson, 2013; Tchamabi et al., 2017).
A brief introduction to the marine environment
Published in Mark Zacharias, Jeff Ardron, Marine Policy, 2019
In the tropical areas of the oceans, both a north equatorial current and a south equatorial current can be recognized flowing from east to west. In the Atlantic and Pacific Oceans, an equatorial countercurrent is found between these two, running from west to east. The Pacific equatorial countercurrent is 8,000nmi in length and about 250nmi in width. The Atlantic equatorial countercurrent is more variable; it becomes stronger in summer, extending its influence westward towards South America.
Practical aspects of meteorology and oceanography for mariners: A guide for the perplexed
Published in Cogent Engineering, 2018
L. C. Aroucha, H. O. Duarte, E. L. Droguett, D. R. A. Veleda
Regarding oceanographic aspects, Roteiro publication (DHN, 2016) gives the details: average density of sea water varies from a maximum at the Southern Coast (1026.5 kg/m3) to a minimum at Northern (1022.0 kg/m3); average sea surface salinity out of the coast of 35.5, and maximum at the Eastern Coast (37.2) and minimum at Southern (33.3); SST between 20 and 25ºC, with minimum in August–September and maximum in march. The wave climate previously cited is controlled by atmospheric circulation, and are associated with cold fronts (especially at the Southern Coast) and trade winds. At the Northern Coast, waves can also be related to storms and hurricanes at the North Atlantic, and, therefore, the Eastern Coast is to two competing waves systems: east-northeastern and south-southeastern waves (Dominguez, 2006). Circulation patterns at the coast are mainly influenced at the surface by two major currents: North Brazil Current (NBC), that flows to north, and Brazil Current (BC), flowing to the south, which both of them are originated by the bifurcation of the central part of the South Equatorial Current (SEC) at 8–10º N (Lumpkin & Garzoli, 2005; Veleda, Araujo, Zantopp, & Montagne, 2012). The NBC, when retroflects at the Brazilian Northern Coast (6–8º N, 45–48º W), is capable of generating rings moving northwestward (Johns, Zantopp, & Goni, 2003). Finally, the winds from northeast acting at the southern part of the Eastern Brazilian Coast (i.e. Frio Cape) and the Southern Brazilian Coast (i.e. Santa Marta Grande Cape) are responsible for generating upwelling processes of low salinity and temperature waters, affecting locally the weather of these regions (Lobo & Soares, 2007; Stramma, 1999).
On the radius of spatial analyticity for Ostrovsky equation with positive dispersion
Published in Applicable Analysis, 2022
We consider the radius of spatial analyticity for the Ostrovsky equation with positive dispersion where u represents the free surface of a liquid and the positive parameter γ measures the effect of rotation. This Equation (1) was proposed by Ostrovsky [1] as a model for weakly nonlinear long waves in a rotating liquid, by taking into account of the Coriolis force. The Ostrovsky equation describes the propagation of surface and internal waves in the ocean in a rotating frame of reference. These unidirectional propagating waves in the ocean under the presentation of rotation, for example equatorial ocean current, have impacts on fisheries and climate. Controlled by the trade wind, the ocean current near the equator forms two westward-flowing currents, North Equatorial Current (NEC) and South Equatorial Current (SEC); within the doldrums, the eastward Equatorial Countercurrent passes between the NEC and SEC; the Equatorial Undercurrent in the thermocline keeps constant eastward flowing against the NEC and SEC. Research on such waves has important physical significance [2,3]. In Equation (1), β determines the type of dispersion, more precisely, (negative dispersion) for surface and internal waves in the ocean or surface waves in a shallow channel with an uneven bottom, and (positive dispersion) for capillary waves on the surface of a liquid or for oblique magneto-acoustic waves in plasma [4–9]. The Cauchy problem of the Ostrovsky Equation (1) has also been examined [10–17]. The results in [13,15,18] showed that is the critical regularity index for Equation (1) in Sobolev spaces. Recently, Yan et al. [19] proved that the Cauchy problem for the Ostrovsky equation with positive dispersion is locally well posed in .