Abstract
Nearshore current generation at two coastlines contemplated for beach resort development is studied with the use of a numerical model for coexisting waves and currents. A nested-mesh technique was applied to consolidate the 2 domains of coarse and fine bathymetric data and to translate deep water wave conditions at the nearshore mesh boundary. The hydrodynamic model is validated using tide data at the nearest tide stations, while offshore wave conditions, determined from a wave hindcasting method, are inputted as quasi-stationary forcing. Simulations results of wave-current co-existing fields indicate local areas of rip currents within the project coastlines. In order to evaluate the safe swimming zones, an analysis of threshold currents under idealized conditions of human characteristics was carried out, that indicated a threshold of 0.16 mps for pure currents. With a safety margin to account for co-existing waves, rip current zones not exceeding 0.1 mps are considered safe and are used to designate the safe swimming areas for the 2 locations.
Highlights
In conjunction with a coastal resort and beach development project along the elongated island of Palawan, two beach coasts facing the West Philippine Sea are exposed to varying swells and wind waves throughout the entire year
Critical longshore and cross-shore current patterns were observed specific to the simulated wave approach directions
Generation of these currents are highly depended on three main parameters: (1) the nearshore bathymetry; (2) incident wave approach direction, wherein the frequency is dependent on the season; and (3) the coastline shape, which partially determines the suitable zone where the return flow out to sea occurs
Summary
In conjunction with a coastal resort and beach development project along the elongated island of Palawan, two beach coasts facing the West Philippine Sea are exposed to varying swells and wind waves throughout the entire year. Prevalent features of Location 1 include curvature of the coastline and a natural groin at the middle of the property composed of coralline and sandy material, which fully emerges during low tide and is submerged during high tide. This area is heavily sheltered by islands, protecting the coast from waves coming from the West to the NW directions. Annual wind data was obtained from Pagasa Island located in the West Philippine Sea (Figure 6), approximately 500 km west of the project area. As seen in the annual wind rose diagram, strong winds up to 16 mps are observed from prevailing wind directions of northeast and southwest which occur during the Amihan and Habagat seasons, respectively
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
