The Effect of Islands on the Wind Wave Spectrum observed in SAR Images
Violante-Carvalho, Nelson1; Humeniuk, J1; Ponce de León, S2; Carvalho, L M3; Guedes Soares, C2
1Ocean Engineering Program Federal University of Rio de Janeiro PEnO COPPE UFRJ, BRAZIL; 22Centre for Marine Technology and Engineering (CENTEC), Instituto Superior Técnico(IST), Technical Univer of Lisbon (UTL), PORTUGAL; 3PPG-EM IME-UERJ, BRAZIL
Wind Wave Spectra retrieved from ERS-2 SAR Precision Images in the neighborhood of a group of islands are employed to investigate the effect of the sheltering in the evolution of the wave field. The SAR wave spectra are inter-compared in the sheltered and non-sheltered zones against NDBC directional wave buoys. Four SAR images were selected from the on-line database of the Catalog of ESA (EOLI) which satisfied criteria of minimum wind speed and certain wave propagation directions. The main focus lies on the swell evolution in the lee side of the islands regarding the changes in the direction of propagation, wave height and directional spreading.