15 May CZM: What have we achieved?
CZM: What have we achieved?
Dr Thrivikramji KP,
email@example.com, Emeritus Fellow, Dept of Geology,
University of Kerala, Kariavattom Campus 695 581
Coastal zone, CZ, is critically placed at the intersection of the chief earth shells like, atmosphere, hydrosphere, and lithosphere. Late awareness on the cross cutting relationship of these shells with ecosystems, ecosphere gained a venerable place in this trinity. The very siting of CZ, all investments, assets, habitation centers and resources are open to natural and manmade calamities or threats. For example, eleven of the fifteen largest cities of the world are sited near the coasts (i.e., in the coastal land zone, CLZ) of seas or estuaries. In India, state capitals of some littoral states (e.g., Mumbai of Maharshtra, Panaji of Goa, Trivandrum of Kerala, Chennai of Tamil Nadu and Kolkotta of WB) are in the coastal land. The shore zone, a sea ward edge of CZ, with water front is most valued real estate and attracts beach lovers. Coastal fisheries, focused on the shelf zone, the SZ, attract tens of millions of citizens to seek and make a substantial income for leading a relatively better quality of life. The intrinsic geospheric processes and extrinsic anthropogenic interventions expressly demand scientific management of the coastal zone to make it safer to members of ecosystem, assets and environmental health.
The conterminous India, with its fairly long shoreline of 5700 km, (i.e., ~10%) and proximity to the equator, has its own share of worries arising out of natural hazards special to CZ. Vulnerability of the population in the CLZ to hazards is directly linked to the morphology of the CLZ (viz., elevation), population density and consequent suproximity of population pockets to the SZ, or in other words the placing assets and lives “inappropriately”. Yet, all across the world, the CLZ is home to mega population centers and scores of smaller cities and towns, which are wide open to and practically defenseless against the most destructive forces of nature like, severe-storm-related hazards, hydrologic floods, beach erosion and tsunamis. Added to this, several coastal communities face massive threats to livability and property primarily contributed by anthropogenic actions, like green house warming induced sea level rise, land subsidence due to mining or withdrawal of fluids from subsurface, pollution of coastal waters, oil spills and sea water ingress into coastal aquifers.
Human populations, cities, ports, and wetlands in low-lying coastal areas, will be affected by inundation, erosion and now added salination of aquifers as a result of a climate change induced sea level rise between 0.3 and 0.9 m say by the end of this century, due to global climate change. Consequences of a global sea level rise would be spatially non-uniform because of local or regional vertical crustal “movements”, differential resistance of shoreline to erosion, varying wave climates, and changing long shore currents. Intensive development and investment in the coastal land make them vulnerable at the time of erosion, hydrologic storms, storm surges or tsunamis. `
Vulnerabilities due to Coastal hazards are preventable either by structural interventions or simply by staying away or relocating in the backshore of zones potential threats. While the structures reflect the wave energy, the natural vegetation helps to absorb the same. Options are two sided, like, do nothing and get out of the area or adapt and accommodate. One of the management responses is retreat from the affected area and move toward the backshore. Secondly by building elevated houses on stilts, the affected communities could be saved. Third option is basically preparedness like education and creating awareness and placing early detection, warning and communication and emergency evacuation systems. Preparedness on the part of local and state or national governments in warding off the damages of hazards is fundamental to it.
But for the recent launch of a program by the MoEF, GoI for mapping the vulnerable coastal areas of the Indian littoral states and creation of an institute in Chennai for research on coastal hazards, not much is in the national agenda. But in the states of the union, enthusiasm on Global Climate Change stands as a scientific issue that is left to fancies and fantasies of the scientific community. In spite of the timelines, like 2025, 2050 and a distant 2100, mapped by and proposed in the IPCC reports, the administration so far did not come up with an action plan.