Three islands namely Lohachara, Suparibhanga and New Moore Island/South Talpatti Island of the Sundarbans have eroded due to dynamic deltaic subsidence but not been submerged due to rising sea level.  Loss of land erosion through bank erosion due to action of waves and storm surges is more pronounced in the islands of Sundarbans.  The Andaman and Nicobar islands have steeper slopes and hence danger from the inundation due to sea level rise is small. 

            Studies on shoreline changes around the Sundarbans delta using satellite images and topo sheets have indicated significant erosion of many islands viz. Ghoramara, Jambudwip, Frasergunj, Bulchery, Dalhousie, Bhangadhuni. Degradation of the Sundarbans is dominated by the destruction of mangroves, erosion-accretion, problems regarding the mixture of fresh and salt water due to sedimentation in the creek and frequent tidal floods, although erosion across the islands of the Sundarbans is more dominant than the accretion.  These islands may again show up intermittently if the accretionary processes predominate in future. 

            Under a major initiative of Ministry of Environment and Forests, a National Institute for Mangrove Research is being planned in the Sunderbans area to provide a scientific approach in preserving the mangroves that needed to be evaluated in reducing the vulnerability of sea-facing inhabited islands, besides construction of bridges to provide for evacuation in case of sea level rise situation or Aila-like cyclones in the future.

            This was stated by Shri Prithviraj Chavan,  Minister of State (I/C) for Science and Technology and Earth Sciences in the Lok  Sabha today.

GG/BS