Assessment of coastal erosion along Indian coast on 1 : 25, 000 scaleusing satellite data

Abstract

ABSTRACT:The long stretch of coastline on the either side of Indian peninsula is subjected to varied coastal processes and anthropogenic pressures, which makes the coast vulnerable to erosion. There is no systematic inventory of shoreline changes occurring along the entire Indian coast on 1:25, 000 scale, which is required for planning measures to be taken up for protecting the coast at national level. It is in this context that shoreline change mapping on 1:25, 000 scale for the entire Indian coast based on multidate satellite data in GIS environment has been carried out for 1989-91 and 2004-06 time frame. The paper discusses salient observations and results from the shoreline change inventory. The results show that 3829 km (45.5%) of the coast is under erosion, 3004 km (35.7%) of the coast is getting accreted, while 1581 km (18.8%) of the coast is more or less stable in nature. Highest percentage of the shoreline under erosion is in Nicobar Islands (88.7%), while percentage of accreting coastline is highest for Tamil Nadu (62.3%) and the state of Goa has highest percentage of stable shoreline (52.4%). The analysis shows that the Indian coast has lost a net area of about 73 sq km during 1989-91 and 2004-06 time frame. In Tamilnadu, a net area of about 25.45 sq km have increased due to accretion, while along Nicobar Island about 93.95 sq km is lost due to erosion. The inventory has been used to prepare "Shoreline Change Atlas of the Indian Coast", brought out as Six Volumes for the entire Indian coast.

Shoreline changes in Barren Island, India

“…Hence, to assess the shoreline change, a total of 63 transects were generated with a spacing 25m across it. There are 19 transects (36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55) in 1885-1976 and 1976-2003 2, figure 3, figure 4 and figure 5). Accretion of lava delta for 1885-1976, 1976-2003 and 2003-2018 are described (table 1).…”

“…The velocity of the lahar flow is defined by the ratio of pyroclastic debris to water [45]. At the coastal frontiers, other factors such as strong waves and tides play a key role in shaping the lava delta [47][48][49][50]. Waves and tides are attenuated to lower rates as its increase near shore water depths result in the exodus of a breaker zone near the coast.…”

Analysis of shoreline changes in Vishakhapatnam coastal tract of Andhra Pradesh, India: an application of digital shoreline analysis system (DSAS)

“…Vishakhapatnam-Kakinada coastal corridor is vulnerable due to natural calamities. Severe coastal erosion led to the landward movement of coastline which ultimately impact on coastal infrastructure and features like sand dunes and salt marshes (Rajawat et al 2014).…”

Role of Marine National Park for Sustainable Livelihoods of Artisan Fisherfolk

“…Of the various coastal states of India, Gujarat has the second-longest coastline (Rajawat et al 2015) and is endowed with a bounty of natural resources. Two of the three gulf regions of the country lie in this state.…”