Storm surge vulnerability assessment of Saurashtra coast, Gujarat, using GIS techniques

Abstract

The coastal stretch of Saurashtra, Gujarat, is seriously threatened by storm surges. Hence, assessing the preparedness to storm surge impacts is a major task in coastal disaster management where identification of relative vulnerability of coastal stretches is a prime concern. The aim of this study is to assess coastal vulnerability related to storm surge events along the coastal talukas of Saurashtra coast, by analyzing physical features and demographic variables using Geographical Information System (GIS) techniques. Vulnerability of a taluka is defined in terms of its exposure, sensitivity, and adaptive capacity. We calculated vulnerability of Exposure Index, Sensitivity Index, and Adaptive Capacity Index separately in ArcMap s/w, and the vulnerability map of different indices in the study region was drawn. The Total Vulnerability Index (TVI) is prepared by integrating the above index. The TVI map shows that Kalyanpur, Porbandar, and Talaja talukas are highly vulnerable in comparison with other talukas as they have large area under low-lying, high sensitivity value, and low adaptive capacity value. On the other hand, Diu and Maliya are lower vulnerable due to the presence of rocky/cliffy coast, sand dune, small coastal length and located in elevated region although there exists high population density and built-up area. Our research finding will assist coastal disaster managers and decision makers to plan appropriate measures to minimize the losses due to storm surge impacts.

A Systematic Review of Coastal Vulnerability Mapping

“…Considering it is easier to spatially delineate and quantify exposure to coastal flooding than to other climate hazards like extreme heat and precipitation, some CVMA methodologies tend to oversimplify the problem by using, for example, arbitrary inundation levels, e.g., [74,75] or regional values provided in IPCC scenarios, e.g., [76]. Some authors deemed it sufficient to use a bathtub approach solely based on DEMs to depict the exposure, e.g., [77][78][79]. Such bathtub models, based on the difference between the projected flood water height and elevation, have limited utility as they do not account for the hydrological connectivity and geophysical barriers present in the real settings [80].…”

Study of Shoreline Changes Due to Tidal Flood at the Coastal City of Meulaboh

“…An area that is vulnerable to damage is coastline, the meeting point between land and sea at certain tides capable of changing in a short time [2,3]. Shoreline changes occur due to natural factors and human activities [4,5] which cause accretion and erosion dynamically [6,7]. Changes caused by nature include tsunamis, waves, tidal currents, and flood, while those attributed to humans are marine construction.…”

Comprehensive Assessment of Vulnerability to Storm Surges in Coastal China: Towards a Prefecture-Level Cities Perspective

“…In this case, vulnerability is a function of the character, magnitude, and rate of climate variation to which a system is exposed, its sensitivity, and its adaptive capacity [16][17][18]. Vulnerability index methods, rooted in the aforementioned concepts, have been widely employed in assessing vulnerability to storm surges by integrating various factors across different temporal and spatial scales [19][20][21][22][23]. The integration of different factors into vulnerability assessments heavily relies on data availability and the unique characteristics of the study area.…”