Spiral analysis of vertical currents in Lamong bay

Abstract

Abstract Coastal management is interested in restoring the natural conditions of increasing the comfort of the community after being degraded due to reclamation, as in Lamong Bay. Therefore, it is necessary to know the character of the current pattern vertically in the study area. This paper aims to find out the current vertical pattern by referring to the shape of the Ekman Spiral. This concept is based on the implementation of surveys and the presentation of currents with hydrodynamic analysis in Lamong Bay. The survey has been carried out at five points, presented with measurement results, and analyzed to the character of the current spiral pattern to depth. Tidal measurement and modeling are also carried out to determine the validation of current measurements synchronized with their position and time. The results obtained in the form of a spiral are not exactly according to the shape of the Ekman Spiral theory, namely on the Southern Hemisphere Earth rotating towards the left. The speed is getting lower and smaller i.e. getting smaller and smaller to the depths (average of CM-1: 0.24 m/s for 0.2D, 0.21 m/s for 0.6D, and 0.18 m/s for 0.8D). Validation of tidal and current measurements from measurements and models qualitatively obtained minimal errors.