Coastal Erosion is the wearing away of land and removal of beach sediments by high winds, drainage, wave action, wave currents, and tidal currents. This article throws light on Coastal erosion, the causes behind coastal erosion, findings of the Ministry of Earth Sciences and National Centre for Coastal Research.
Aspirants would find this article very helpful while preparing for the IAS Exam.
Coastline – Importance
Coastal morphodynamics studies the erosion and sediment redistribution in coastal areas. It is caused by corrosion, hydraulic action or abrasion.
The beaches and shorelines in India serve multidimensional needs such as seaport for maritime commerce, space for residential & commercial structures, recreational purposes etc. Developmental activities along the coastline have increased and the trend is expected to continue in the decades to come. Similar to any other maritime country, India’s long peninsular region constantly battles erosion. The developmental activities are often carried out without a clear understanding of the coastal dynamics. This leads to a long term, in the worst cases, permanent damage particularly to the local communities.
Aspirants should read the related topics from below:
|Coastal Plains in India||List of Ramsar Sites in India|
|Ramsar Convention 1971||Difference between Western and Eastern Ghats of India|
|Difference Between Western and Eastern Coastal Plains||Biodiversity Hotspots|
Coastal Erosion – Reasons
- According to the Ministry of Environment, Forest and Climate Change (MOEFCC) 40% of India’s coastline is subjected to high, medium or low coastal erosion.
- Wave energy is considered to be the primary reason for coastal erosion.
- Natural hazards like cyclones, thermal expansion of seawater, storm surges, tsunami etc due to the melting of continental glaciers and ice sheets as a result of climate change hamper the natural rhythm and precipitate erosion.
- Strong littoral drift resulting in sand movement can also be considered as one of the major reasons for coastal erosion.
- Dredging, sand mining and coral mining have contributed to coastal erosion causing sediment deficit, modification of water depth leading to longshore drift and altered wave refraction.
- Coastal erosion has been sparked by fishing harbours and dams constructed in the catchment area of rivers and ports reducing the flow of sediments from river estuaries.
Ministry of Earth Sciences – Findings
- About 89% of the shoreline of Andaman and Nicobar Island is eroded by the Bay of Bengal.
- Goa has the highest percentage of stable shoreline.
- With 62% of its coast gaining land, Tamil Nadu has gained the newest shoreline.
National Centre for Coastal Research – Findings
- From 1990 to 2016, 33% of India’s coastline has witnessed erosion.
- Majority of the erosion was witnessed along the East Coast facing the Bay of Bengal.
- Among the states along the East Coast, West Bengal faced the highest erosion.
Coastal Erosion – Preventive Measures
- Improving vegetation along the coastline, which is important for improving slope stability and providing shoreline protection.
- Using Geosynthetic tubes that are being used along the coast in Odisha.
- Building out into the sea, low walls or barriers called groynes to check drifting.
- Making use of indigenous knowledge of local communities prior to decision making with respect to developmental projects along the coastline.