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The equatorial deep jets (EDJ) are a striking feature of the equatorial ocean circulation. In the Atlantic Ocean, the EDJ are associated with a vertical scale of between 300 and 700 m, a time scale of roughly 4.5 years, and upward energy propagation to the surface. It has been found that the meridional width of the EDJ is roughly 1.5 times larger than expected based on their vertical scale. Here, the authors use a shallow-water model for a high-order baroclinic vertical normal mode to argue that mixing of momentum along isopycnals can explain the enhanced width. A lateral eddy viscosity of 300 m2 s−1 is found to be sufficient to account for the width implied by observations. [ABSTRACT FROM AUTHOR]

The first observations of microbaroms with single absolute barometers are presented and discussed. Microbaroms are pulses of atmospheric infrasound emitted by ocean surface waves. They can propagate over thousands of kilometers through the atmosphere, and they can reach altitudes well into the upper atmosphere before they are refracted down to the earth''s surface. Typical microbarom periods are 5 s, typical wavelengths are 1.5 km, and typical surface amplitudes are 100 mPa (1 μμbar). The data presented here were collected during the 2-week period from 26 February through 10 March 2008 in Amherst, Massachusetts, which is located about 150 km away from the Atlantic Ocean. The authors report for the first time, to the best of their knowledge, an f−−5 microbarom frequency spectrum, which is consistent with Phillips''s f−−5 ocean surface wave equilibrium spectrum. [ABSTRACT FROM AUTHOR]

Accurate predictions of wind waves with different lead times are necessary for a large scope of coastal and open ocean activities. Attempts to improve wave short-term forecasts based on artificial neural networks are reported. Hourly observations of significant wave heights and zero-up-crossing wave periods from two sites offshore the Atlantic and the Irish Sea coasts of Ireland are used to train and validate these networks. Two different approaches are involved. One of them corrects the predictions solely using the initial simulations of the wave parameters with leading times from 1 to 24 h. Another one allows merging the measurements and initial forecasts. The proposed procedures provide satisfactory results at both locations. [Copyright &y& Elsevier]