Answer: Coastal erosion is the wearing away of land by action of waves, currents and wind. Coastal erosion is accompanied by the landward recession of the shoreline and loss of land area. Human activities like construction of coastal structures, beach sand mining, offshore dredging, etc., have also triggered coastal erosion. 

• There are four main processes of coastal erosion. These are corrasion, abrasion, hydraulic action and attrition.

• The Ministry of Earth Science (MoES) recently informed that 34% of coastline is under varying degrees of erosion for the past 28 years. West Bengal is the worst hit with over 60% of its shoreline under erosion. 

• Ecological degradation: Nearly 60% of the world's coral reefs have significantly deteriorated, 50% of all mangroves have vanished, and half of all wetlands have disappeared.
• Loss of land: It is brought on by both accelerated rates of sea level rise and decreased sediment delivery by the rivers.
• Increasing Vulnerability of Population: The majority of people live within 100 kilometers of the coastline. Environmental deterioration occurs in certain coastal regions, and developing nations are particularly affected.
• Pollution: The quality of much of the world's freshwater is declining due to pollution from industry, agriculture, and urban areas.
• Depleted resources: Endemic coastal fish stocks are now just 10–30% of what they were thirty years ago due to overfishing.

• Indian National Centre for Ocean Information Services (INCOIS) has carried out Coastal Vulnerability Index (CVI) mapping to assess implications of sea-level rise along the Indian coast. 
• National Centre for Sustainable Coastal Management (NCSCM), Chennai to research in the area of CZM including coastal resources and environment.
• Integrated Coastal Zone Management Plan (ICZM) to ensure optimum sustainable use of coastal natural resources. ICZM plans aim to regulate coastal development, conserve coastal ecosystems, and reduce erosion risks.
• The Ministry of Earth Sciences, in its reply, highlighted that the 15th Finance Commission had suggested ‘Mitigation Measures to Prevent Erosion’ under National Disaster Mitigation Force (NDMF) and ‘Resettlement of Displaced People Affected by Erosion’ under National Disaster Response Force (NDRF).
• At present, the National Disaster Management Authority (NDMA) is preparing suitable norms for mitigation measures and developing a policy to deal with the extensive displacement of people from coastal areas.

Coastal erosion is a severe problem for maritime developing countries like India, and immediate attention needs to be given to combat coastal erosion effectively on a scientific basis for evolving suitable designs of coastal protective structures.