On the feasibility of the use of wind SAR to downscale waves on shallow water

n recent years, wave reanalyses have become popular as a powerful source of information for wave climate research and engineering applications. These wave reanalyses provide continuous time series of offshore wave parameters; nevertheless, in coastal areas or shallow water, waves are poorly described because spatial resolution is not detailed. By means of wave downscaling, it is possible to increase spatial resolution in high temporal coverage simulations, using forcing from wind and offshore wave databases. Meanwhile, the reanalysis wave databases are enough to describe the wave climate at the limit of simulations; wind reanalyses at an adequate spatial resolution to describe the wind structure near the coast are not frequently available. Remote sensing synthetic aperture radar (SAR) has the ability to detect sea surface signatures and estimate wind fields at high resolution (up to 300?m) and high frequency. In this work a wave downscaling is done on the northern Adriatic Sea, using a hybrid methodology and global wave and wind reanalysis as forcing. The wave fields produced were compared to wave fields produced with SAR winds that represent the two dominant wind regimes in the area: the bora (ENE direction) and sirocco (SE direction). Results show a good correlation between the waves forced with reanalysis wind and SAR wind. In addition, a validation of reanalysis is shown. This research demonstrates how Earth observation products, such as SAR wind fields, can be successfully up-taken into oceanographic modeling, producing similar downscaled wave fields when compared to waves forced with reanalysis wind

Wave modelling in the Ecuadorian Pacific using WAVEWATCH III and SWAN

During the last few decades, the study of ocean waves has been a focus of attention and, consequently, many developments in this field have been achieved (e.g., numerical wave models). Many of those numerical models are distributed under the terms of the GNU General Public License (e.g., WAVEWATCH III, SWAN). The wind wave model WAVEWATCH III particularly has been widely implemented in many countries to predict and simulate wind waves, mainly in ocean scale domains. The SWAN model, on the other hand, is more specialized in regional and coastal domains. The present work is focused in the prediction of wind waves in the Ecuadorian Pacific, using the capabilities of these two models. The operational wave model implemented provides output (e.g., Significant wave height and Peak period) available at http://ocean.usfq.edu.ec. As part of this implementation, the influence of sea ice extent in the Antarctica was evaluated, showing situations of large impacts in the wave conditions at the Ecuadorian coast. Finally, different alternatives to specify boundary conditions for the coastal model SWAN were studied. The results shows that there is not a major difference between them for the cases studied. However, further research is needed for more general boundary conditions.Durante las últimas décadas, el estudio del oleaje ha sido un foco de atención y, consecuentemente, muchos avances han sido logrados en este campo (e.g., modelo numéricos de oleaje). Muchos de estos modelos numéricos son distribuidos bajo los términos de la Licencia Pública General de GNU (e.g., WAVEWATCH III, SWAN). El modelo numérico WAVEWATCH III particularmente ha sido implementado en varios países para predicción y simulación de oleaje, principalmente en dominios de escala oceánica. El modelo SWAN, por otro lado, es más especializado en dominios costeros y regionales. El presente trabajo se enfocó en la predicción de oleaje en el Pacífico Ecuatoriano, usando las bondades de estos dos modelos. El modelo operacional de oleaje implementado provee salidas (e.g, Altura significante y Periodo pico) disponibles en http://ocean.usfq.edu.ec. Como parte de esta implementación, la influencia de la extensión de la cobertura de hielo en la Antártica fue evaluada, mostrando situaciones de gran impacto en las condiciones de oleaje en la costa Ecuatoriana. Finalmente, se estudiaron diferentes alternativas para especificar condiciones de borde para el modelo costero SWAN (i.e., constante y distribuida). Los resultados muestran que no hay mayor diferencia entre ellas para los casos estudiados. Sin embargo, se necesita más investigación para condiciones de borde más generales

Surface Gravity Wave Modeling in Tropical Cyclones

Tropical cyclones are among the deadliest geophysical phenomena on earth. Tropical cyclone-generated wave fields are of interest both scientifically for understanding wind–wave-ocean interaction physics and operationally for predicting potentially hazardous conditions for ship navigation and coastal regions. This chapter briefly reviews the development of third generation wave models, the improvements of their input/dissipation source functions, and their applications in tropical cyclone generated surface wave predictions. Discussion on the status of coupled atmosphere-wave-ocean modeling in tropical cyclone predictions are given at the end of the chapter prompted by the growing scientific evidence on the importance of sea state on air-sea fluxes under extreme wind conditions

Modular System for Shelves and Coasts (MOSSCO v1.0) - a flexible and multi-component framework for coupled coastal ocean ecosystem modelling

Shelf and coastal sea processes extend from the atmosphere through the water column and into the sea bed. These processes are driven by physical, chemical, and biological interactions at local scales, and they are influenced by transport and cross strong spatial gradients. The linkages between domains and many different processes are not adequately described in current model systems. Their limited integration level in part reflects lacking modularity and flexibility; this shortcoming hinders the exchange of data and model components and has historically imposed supremacy of specific physical driver models. We here present the Modular System for Shelves and Coasts (MOSSCO, http://www.mossco.de), a novel domain and process coupling system tailored---but not limited--- to the coupling challenges of and applications in the coastal ocean. MOSSCO builds on the existing coupling technology Earth System Modeling Framework and on the Framework for Aquatic Biogeochemical Models, thereby creating a unique level of modularity in both domain and process coupling; the new framework adds rich metadata, flexible scheduling, configurations that allow several tens of models to be coupled, and tested setups for coastal coupled applications. That way, MOSSCO addresses the technology needs of a growing marine coastal Earth System community that encompasses very different disciplines, numerical tools, and research questions.Comment: 30 pages, 6 figures, submitted to Geoscientific Model Development Discussion