IEEE logo

Upwelling effect on acoustic propagation in the Cabo Frio Island Bay

23rd International Congress on Acoustics 2019, Aachen (Germany)

R.C. Moraes rgc_moraes(at),
V.J. Barroso vicente.barroso(at),
M.V. Simoes simoes(at),
IEAPM, Arraial do Cabo (RJ), Brazil.
S.M. Jesus sjesus(at),
LarSys, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal).

Comments: no download yet.
Ref.: in ICA'19, Aachen (Germany), September 2019 (invited).

Coastal upwelling is an oceanographic phenomenon that challenges the understanding of acoustic propagation, especially when it extends to shallow water areas with complex geographic configuration. The data used in this paper was collected in a semi-enclosed bay filled by the upwelling stream through an inlet off the island of Cabo Frio, in the coast of Brazil. The experiment was carried out in January 2019, under BIOCOM, a joint initiative between the Brazilian Navy and the University of Algarve (Portugal). Broadband acoustic signals were transmitted over a 1.6 Km-long transect across the upwelling flow during five days. These signals were superimposed in a soundscape formed by a strong biological acoustic signature and boat engine noise due to close by recreation boats. Signals were received in two hydrophone arrays: one vertical and another horizontal, close to the bottom. The comparison of received data with that generated with a 3D acoustic propagation model shows good prospects for water column properties inversion. The ability to track temperature changes of the highly dynamic system formed by the conjunction of the upwelling stream, the tide and the wind, allows for improving the performance of vertical line arrays for other tasks such as source detection and localization.

ACKNOWLEDGMENT: This work was funded under project BIOCOM, from CsF (Brazil).