Beach stability in relation to the nearshore wave energy distribution along the Quilon coast, SW coast of India

Abstract

<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">The study covers the short- and long-term beach volume changes, shoreline changes, wave refraction pattern and nearshore wave energy distribution. In general there is a decrease of wave energy towards north. The distribution of wave energy for monsoon shows that the highest value of 5215 J/m² is found in the southern most station and lowest value of 4043 J/m²<i> </i>is found in the northern most station. The computation of short- and long-term beach volume changes indicate that the beaches of the southern sector are nearly stable while the northern sector beaches are eroding. In addition to the wave and wave-induced processes, the anthropogenic factors such as sand mining by IRE, presence of breakwaters at Ashtamudi inlet and lack of sediment supply from the rivers contribute to the continuous erosion in the northern sector. The erosion/accretion pattern closely follows the longshore energy gradient except in locations where anthropogenic factors dominate.</span>