Abstract:
Erosion of the coastline is a common phenomenon, the battle between the sea and land is known to humans since ancient times. Unfortunately, with rising human population along the major coastlines of the world due to socio-economic reasons, an increase in the rate of erosion has been observed. And now as much as 70% of the world’s coastline are reported to be going through erosion. This high trend can also be attributed to climate change leading to an unusual rate of erosion that is now threatening to vanish coastlines and important ecosystems. With Balouchistan, previously ignored by the government set to go through rapid change with the upcoming China Pakistan economic corridor (CPEC) project, a need for a detailed scientific assessment of the rate of erosion was direly needed. Physical on ground surveys for estimation of erosion is a laborious, capital intensive and a time consuming work, hence modern GIS techniques come into play. This study “erosion mapping of the coastline of Balouchistan and western Sindh” employs the Digital shoreline analysis system (DSAS), a toolbox developed by the United States Geological Survey (USGS). It has already proved its worth and accuracy in worldwide coastal erosion studies, with a number of research articles published to prove it. The approach to this study is fair and simple, starting with Landsat imagery for a duration of 2000-2010-2015, atmospherically corrected using S6 algorithm to the actual digitization and analysis by DSAS means the results can be duplicated easily by any interested researcher as it will be discussed in detail in this study.
The geology of the western coastline has a direct relationship withe trends of erosion, such as the case of Jiwani and Gwadar and Ormara. The hammer head formations at Gwadar and Ormara and the cliff of Jiwani are rock and rough areas which are in nature more prone to erosion due to the lashing waves. The least amount of change in the Hub and Karachi area is suggestive of the flow of Hub River dividing Balochistan and Sindh. The regular flow of sediments keeps the rapid erosion in check in the Hub region
