NEWS

As per Ministry of Earth Sciences Bengal coast faces most erosion

DETAILS

• It was said by Ministry of Earth Sciences
• Of the 6,907.18-km-long coastline of the Indian mainland
  • 34% is under varying degrees of erosion
  • 26% is of an accretional nature
  • 40% is in a stable state
• Coast is monitored by the National Centre for Coastal Research (NCCR), Chennai using remote sensing data and GIS mapping techniques
• In terms of percentage, West Bengal, located on the eastern coast of the country, with a 534.35-km-long coastline, suffered erosion along about 60.5% of the coast (323.07 km) over the period from 1990 to 2018
• This is followed by Kerala on the west coast, which has 592.96 km of coastline and 46.4% of it (275.33 km) faced erosion. Tamil Nadu, with a long coastline of 991.47 km, recorded erosion along 42.7% of it (422.94 km)
• Gujarat, with the longest coastline of 1,945.6 km, recorded erosion along 27.06% (537.5 km) of it. In the Union Territory of Puducherry, with a 41.66-km-long coastline, about 56.2% of its coast (23.42 km) recorded erosion
• Another organisation under the Ministry, the Indian National Centre for Ocean Information Services (INCOIS) has prepared and published an atlas of Coastal Vulnerability Index (CVI) maps for the entire coastline of India at a 1:100000 scale, the Ministry informed Parliament.
• The Ministry stated that the 15th Finance Commission had recommended the creation of a National Disaster Risk Management Fund (NDRMF) and State Disaster Risk Management Fund (SDRMF) comprising a mitigation fund at the national and State levels (NDMF/SDMF), and a response fund at the national and state levels for the award period from 2021-22 to 2022-26.

COASTAL EROSION

• Wearing away of land and removal of beach sediments by high winds, drainage, wave action, wave currents, and tidal currents
• Caused by corrosion, hydraulic action or abrasion.
• Coastal erosion can be either a:
  • rapid-onset hazard (occurs very quickly, a period of days to weeks)
  • slow-onset hazard (occurring over many years, or decades to centuries).

CAUSES OF 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.
• Heavy rainfall can enhance the saturation of soils, with high saturation leading to a reduction in the soil’s shear strength, and a corresponding increase in the chance of slope failure (landslides).

NEED FOR PREVENTION OF COASTAL EROSION

• The coastal regions where land and water meet are ecologically dynamic and sensitive regions, as marine and coastal ecosystems continuously impact on each other.
• These regions have a rich ecosystem such as mangroves, water bodies, seaweeds coral reefs, fisheries and other marine life, and other coastal and marine vegetation.
• These ecosystems protect the region from saline winds, cyclones, tsunami waves etc., promote carbon sequestration and promote biodiversity as well as provide raw materials for a number of manufacturing activities. Hence, this is an alarming situation for us to overcome from the coastal erosion.