Redirigiendo al acceso original de articulo en 21 segundos...
ARTÍCULO
TITULO

Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model

Sonia Ponce de León and C. Guedes Soares    

Resumen

The influence of the Agulhas Current on the wave field is investigated. The study is conducted by performing high resolution spectral wave model simulations with and without ocean currents. The validation of the numerical simulations is performed for the Significant Wave Height (Hs) using all possible satellite altimetry data available in the study region for a winter period of 2018. Wave spectra and extreme waves parameters are examined in places where waves and current are aligned in the Agulhas Current. Sentinel-1 (S1) wave mode Synthetic Aperture Radar (SAR) spectra are used to estimate the composites of the Hs and BFI (Benjamin?Feir Index). SAR computed BFI and Hs were compared with the respective composites obtained from the Simulating Waves Nearshore (SWAN) model. From the Hs composites using SAR data and modeled data, it can be concluded that the Hs maxima values are distributed in the Agulhas Current Retroflection (ACR) and also in the southern limit of the domain that is affected by the strong circumpolar winds around Antarctic. In addition, the BFI composites exhibit the highest values in the ACR and some few values are observed in the southern border as occurred with the Hs. The results of this study indicate that there is direct correlation between the Agulhas Current strength, the Hs and the BFI. It was found that the modeled directional wave spectra are broadened when the ocean current is considered in the simulation. The analysis of the modeled wave spectra is performed over eddies, rings and meanders in the Agulhas Current region. The transformation of the wave spectra due to current refraction is discussed based on the numerical simulations. The effect of the Agulhas Current on the spectral shape is explored. The spectral wave energy grows when the wave and the current are aligned, resulting in peaked, elongated and widened spectra. A decrease of the peak period was observed before the occurrence of maximum values of BFI, which characterize abnormal sea states.

 Artículos similares

       
 
Liu Zhu, Yuan Cheng, Jinfang Wang, Hongyu Zhu and Zhijing Xu    
The nonlinear dynamic response of an aquaculture cage array caused by wave-frequency and low-frequency excitations coupled with the nonlinearity of the mooring and the netting system is a complicated problem. So far, this problem still has not been compl... ver más

 
T. Yuan, X. Wang, K. Qu and L. B. Zhang    
Driven by strong winds, huge ocean waves can cause devastating destruction to coastal regions during harsh weather events. There is growing evidence showing that extreme waves can occur in both shallow and deep waters. To protect the coast against the de... ver más

 
Moleni Tu?uholoaki, Antonio Espejo, Moritz Wandres, Awnesh Singh, Herve Damlamian and Zulfikar Begg    
The South Pacific region is characterised by steep shelves and fringing coral reef islands. The lack of wide continental shelves that can dissipate waves makes Pacific Island countries vulnerable to large waves that can enhance extreme total water levels... ver más

 
Jens Engström, Zahra Shahroozi, Eirini Katsidoniotaki, Charitini Stavropoulou, Pär Johannesson and Malin Göteman    
Wave energy conversion is a renewable energy technology with a promising potential. Although it has been developed for more than 200 years, the technology is still far from mature. The survivability in extreme weather conditions is a key parameter haltin... ver más

 
Martin Moreau, Grégory Germain and Guillaume Maurice    
The cost effective design of tidal turbines requires a good estimation of the loading cycles and their extrema that are related to the unsteady fluctuation of the current velocity. Apart from the ambient turbulence, the main source of velocity fluctuatio... ver más