Effi Helmy Bin Ariffin
Thesis defended on September 28th 2017
in Lorient
Marine Sciences
Effect of Monsoons on Beach Morphodynamics in the East Coast of Peninsular Malaysia : Examples from Kuala Terengganu coast
Abstract
In Southeast Asia, coastal dynamics are governed by a special equilibrium between northeast an southwest monsoons. In the context of sea-level rise and climate change, the monsoon regimes create an adaptation of the coastal dynamics. This situation gives rise to erosion phenomena along the coastline. However, public authorities have attempted to mitigate the problems of erosion by the construction of coastal defence structures. However, artificial structures can affect the wave regime, hydrodynamic circulation and sediment transport, thus reducing the ability of the shoreline to respond to natural forcing factors (such as with double monsoon season regimes) and also fragmenting the coastal space. The present thesis explores the problems of erosional phenomena, shoreline evolution and beach morphodynamics along the Kuala Terengganu shoreline on the East Coast of Peninsular Malaysia, with the aim of understanding the natural versus anthropogenic factors. This study was conducted in three phases to address the following topics: i) shoreline evolution from 2006 to 2014; ii) mid-term surveys (bi-monthly) involving data collection from July 2013 until June 2015 and; iii) short-term surveys (twice daily) with data collection (Topographic, hydrodyanamic and sediment transport measurments) during northeast and southwest monsoons. Based on a morphodynamic model for simulating seasonal processes, erosion is found to dominate most of the stations during northeast monsoons, while accretion or beach recovery is observed during southwest monsoons.