Coastal vulnerability assessment of Gujarat coast to sea level rise using GIS techniques: a preliminary study

Abstract

Assessing the preparedness of the coastal region to the anticipated sea level rise is a major task among the coastal management authority, where identification of relative vulnerable of coast is a prime concern. The present research work has utilized Remote Sensing and GIS techniques for assessing vulnerability of the Gujarat coast due to predicted sea level rise. Synergetic use of satellite remote sensing, numerical simulations and filed observations has been done to generate coastal thematic information followed by validation. Coastal vulnerability assessment of the entire Gujarat coast on 1:50, 000 scale were carried out considering five physical parameters. They are; coastal geomorphology, coastal slope, shoreline change rate, mean spring tidal range, and significant wave height. The rank values of all the five physical variables are integrated through additive method to compute a Coastal Vulnerability Index (CVI) where the relative ranking is assigned to various coastal segments based on the vulnerability level. The CVI values categorize Gujarat coast into four risk level classes. The results show that 785 km (45.67 %) of the Gujarat coast is under high to very high risk category and 934 km (54.33 %) of the Gujarat coast is under Moderate to Low risk category due to an anticipated rise in sea level. The coastal regions under very high risk category are along northwestern parts of the Gulf of Khambhat, the northernmost parts of the Gulf of Kachchh and western parts of the Kachchh coast. The southern parts of the Saurashtra coast and southwestern parts of the Kachchh coast is under the low risk category along with isolated segments along the eastern parts of the Gulf of Khambhat. The approach developed for assessing vulnerability of the coast to predicted sea level rise using remote sensing and GIS techniques can be used effectively by coastal management authorities and decision makers to devise better coastal zone management plans as well as to ensure efficient mitigation measures to minimize the losses due to possible impact of predicted sea level rise through which appropriate measures to protect life, property and environment can be timely planned.

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

“…The Geoarchaeological site in Dwarka and Shiva temple at Somenath near Veraval attracts many tourists. The mean tidal range of the eastern side of the study region is higher (4.2 m at Talaja) in comparison with the western side (1.71 m at Okhamandal), whereas the mean significant wave height is about 3 m from Okhamandal and decreases toward Talaja (Mahapatra et al 2015b). …”

Remote Sensing of Narrowing Barrier Islands along the Coast of Pakistan over Past 30 Years

“…For a better comparison among different BIs, a spatial histogram plot of the LRR-based erosion/accretion statistics for each BI was plotted (Figure 5). These plots help us assess the severity of erosion/accretion in more detail for each BI, providing a broader range of information to coastal planners and decision makers [50,51]. Further analysis of erosion and accretion at different transects facing the Arabian sea and the mainland showed signs of translocation of large sand bodies in different BIs (e.g., BIs 15 and 16).…”

Three Decades of Coastal Changes in Sindh, Pakistan (1989–2018): A Geospatial Assessment

“…An intensity curve was plotted based on the LRR for each subzone. A linear regression statistics-based decision matrix was also devised to assess the severity of erosion/accretion in each zone and subzone [17,45].…”