Global mean sea level is rising at an accelerating pace is happening because of melting of ice sheets in polar and high mountain areas, thermal expansion of water owing to higher temperatures, subsidence of land, groundwater expansion and lesser availability of sediments in coastal areas.
Impact of Sea Level rise on India and Indian Ocean regions:
- Permanent submergence of low-lying areas coastal areas, atolls and limestone islands by higher mean sea levels or mean high tides. Ex. Maldives, Mumbai, Sundarbans delta etc.
- Increase in frequency of extreme weather events like tropical cyclones – destruction of life and property.
- Salinisation of groundwater aquifers, wetlands and soils leading to crises of freshwater availability and damaging agriculture in coastal areas.
- Enhanced coastal erosion: Sea level rise along with depleted sediment supply will trigger erosion on shorelines.
- Chronic flooding at high tides particularly in low-lying areas and islands.
- Loss and change of coastal ecosystems and resulting ecosystem services.
- Landward expansion of vegetation as vegetation on coasts cannot saline water intrusion and coastal characters shifting inwards.
- Impeded drainage in coastal areas as natural flow of water will be impeded in low-lying areas leading to flooding.
Socio-economic impacts of sea level rise:
- Refugee crisis as millions living on coasts are forced to move inwards.
- Damaging of Coastal infrastructure and ports leading to wider economic consequences.
- Compromise of food security in coastal areas
- Increase on population pressure on land as less land will available after submergence.
- Rise of diseases due to water and sanitation crises like diarrhoea, cholera and vector borne diseases like Malaria.
- Social conflict due to lesser availability of land and resources.
Thus, there is a need to prevent adverse impact of sea level rise by immediate, fast and profound mitigation and adaptation actions like land reclamation, ecosystem-based protection (mangroves and reef restoration) and structural interventions like coastal walls, dykes, land-reclamation and regulation of coastal zones (CRZ regulations).