Coastal Inundation Research:An overview of the Process

Abstract

Coastal inundation is the flooding of coastal zone resulting from increased river discharge, spring tides, severe storms, or generation of powerful waves from tectonic activity (tsunami). This article discusses the critical factors that contribute to coastal inundation. Among the probable factors that cause coastal flooding and destruction, storm surge is the most frequent, and hence this article provides a detailed evaluation of the progress made in storm inundation research. Recent advances in coastal inundation modelling include efforts to understand the nonlinear dynamic interaction of near-shore waves, wind and atmospheric pressure with still water sea level and coastal currents, and their combined effects on storm surge along the coast and interaction with coastal morphology. An advanced storm-surge model comprises different modules, viz. an atmospheric component, and two ocean components for surge and wave simulations; these modules are coupled with each other. The nesting of regional coastal model with an ocean-wide model captures the far-field boundary forcing of extreme events that usually originate from the warm open ocean. Even though significant advancements reported on the efficiency and accuracy of storm surge and inundation prediction, further studies are required to understand the nonlinear interaction of storm surge with coastal landforms and their vegetation (land cover). In the context of rising sea level, increased tropical cyclone activity and rapid shoreline change, it is pertinent to evaluate the future flooding risk associated with landfall of tropical cyclones in densely populated coastal cities.

Wave–current interaction during Hudhud cyclone in the Bay of Bengal

“…From the literature review, it is evident that most of the storm surge studies carried out for the Indian coast used stand-alone models (Rao et al, 2013a;Bhaskaran et al, 2014;Gayathri et al, 2015Gayathri et al, , 2016Dhana Lakshmi et al, 2017). A comprehensive review on the coastal inundation research and an overview of the processes for the Indian coast was reported by Gayathri et al (2017). One can find very few studies reported using a coupled model (ADCIRC with SWAN) for the Indian seas (Bhaskaran et al, 2013;Murty et al, 2014Murty et al, , 2016Poulose et al, 2017) for extreme weather events.…”

Compound effects of rain, storm surge, and river discharge on coastal flooding during Hurricane Irene and Tropical Storm Lee (2011) in the Mid-Atlantic region: coupled atmosphere-wave-ocean model simulation and observations

“…Coastal ooding occurs when the sea level at the coast episodically rises above the normal range of the tides (Gayathri et al 2017;Flick et al 2012). MHHW is commonly used as a reference to determine the threshold of coastal ooding.…”

“…The coastal zone faces a variety of threats from severe storms such as tropical cyclones. Coastal ooding can result from several compounding factors, including river discharge, abnormally high astronomical tides such as spring tides, wind-induced storm tides/surges, and ocean surface wave run-up (Gayathri et al 2017). In tropical storms and hurricanes, storm surges and river ooding are the main factors ).…”