Neglected Hazard, Growing Threat: Why Coastal Erosion Demands an Early Warning System
In 2022, United Nations Secretary-General António Guterres launched the ‘Early Warning for All’ (EW4ALL) initiative, aiming to provide universal protection against hydro-meteorological, climatological, and related environmental hazards by 2027 (WMO, 2022). This initiative has advanced the global agenda on anticipatory action by emphasizing the need for user-centric early warning systems, thereby enhancing human security. However, more than halfway through the program, a critical gap remains: the absence of dedicated early warning services (EWS) for coastal erosion, a growing environmental threat with significant global consequences. Despite mounting evidence of its impacts, coastal erosion has not been adequately integrated into the EW4ALL framework. This oversight demands urgent attention, especially as rising sea levels are expected to intensify erosion in vulnerable regions. In India, for instance, a 2018 assessment by the National Centre for Coastal Research (NCCR) found that more than 2,000 km of the country’s shoreline is already undergoing varying degrees of erosion (Kankara et al., 2018).
The response can be categorized broadly into three types: a) building coastal protection measures, b) rehabilitation of displaced population and c) formulating policies, plans, and guidelines to support better coastal management. Firstly, there are central and state government projects aimed at protecting a retreating shoreline, utilizing a range of structural and non-structural mitigation measures. They include embankments of various types, mangroves and other vegetation cover, and offshore breakwaters and reefs using both complex and nature-based solutions (see, for example, CWC Guidelines 2020). The second kind of response is people moving away from the shoreline and relocating to new places, requiring support for their rehabilitation. The third type encompasses initiatives, such as the draft National Policy on Mitigation and Rehabilitation Measures for People Displaced by Coastal and River Erosion (NDMA, 2022). Similarly, several plans and Guidelines have been developed, including the National Strategy for Coastal Protection, Marine Spatial Planning, and Guidelines for implementing Integrated Coastal Zone Management, among others. In all of them, the concept of an early-warning system has yet to be conceived, although such early warnings already exist for hazards such as coastal floods, tropical cyclones, and storm surges.
Why is there no dedicated EWS for coastal erosion?
The combined effects of sea level rise, densely populated coastal regions and vulnerability of people pose a serious threat, but then what explains the absence of an Early Warning System (EWS) for coastal erosion? There are several reasons, one of which is the slow onset nature of the hazard, occurring over years and decades in a manner where the idea of an early warning appears to be meaningless. This, however, is not entirely justified. For example, the earliest conception of an Early Warning System (EWS) dates back to the 1970s, when a Global Information and Early Warning System (GIEWS) was established in response to a drought in Ethiopia. Subsequently, a Famine Early Warning System (FEWS) was put in place for East and West Africa. Before it, there were forewarning services for hazards such as tropical cyclones, though not on the same level as an EWS framework or one that linked warning services with user requirements. Famine or drought, to note, are also slow-onset hazards. The second possible reason is the nature of the impact of coastal erosion, which, although widespread, is limited to a local region at a particular time. This is in sharp contrast to cyclones or tsunamis, which cause devastating impacts when they occur, drawing far more attention. The cumulative impact of coastal erosion, however, is significant, although it is both spatially and temporally diffuse. One can draw a parallel, for example, with hazards such as lightning (Mishra et al., 2024) or road accidents (Ministry of Road Transport and Highways, 2022), for which societal attention could be drawn more forcefully only when aggregated human deaths for such hazards are statistically reported. This is an aspect that needs to be addressed for coastal erosion in the country. The third and perhaps more plausible explanation is that it is not entirely evident what kind of information should be provided as part of coastal erosion early warning, and how that information will be helpful to people. Unlike a thunderstorm, tsunami, or tornado, where the public is warned of the severity of a hazard and is informed of potential consequences, coastal erosion is an ongoing process, thus reducing the scope for forecasting elements, and it is also unclear as to what action can people take at their level to deal with such an emerging threat?
A brief sketch for Coastal Erosion EWS
Three key components can be envisioned for a Coastal Erosion Early Warning System in the country: a routine surveillance system, scientific modelling exercises to build impact scenarios, and management initiatives, including risk mitigation and plans to utilise available inputs.
Robust surveillance system. The existing shoreline mapping exercise should be undertaken as a routine function rather than a periodic exercise, and it should be coordinated by an appropriate agency at the central level. It should utilize all available technological means, including remote sensing data and artificial intelligence, to generate shoreline change analysis on a continuous basis. Further, such analysis needs to be validated with field reports involving trained local volunteers to provide a more precise estimate. The latter should be an essential feature, drawing from the emerging EWS concept of ‘first mile’, which lays greater emphasis on making local communities part of EWS at an upstream level.
Erosion risk assessment at the local level. A major challenge confronting the development of an effective EWS is generating models that can estimate coastal erosion risk for a particular coast with a reasonable degree of reliability. Such models will need to factor in a range of dimensions, for example, the rate of sea level rise, changes in sediment flow and tidal currents, geological and topographical features, the impact of extreme weather events such as tropical cyclones, and that of storm surge, which often plays a crucial role. It will also need to include the influence of various coastal structures, changes in land use, and practices related to marine resource extraction, such as offshore mining. Developing such models is a formidable task, requiring not just large amounts of data but also utilizing them in a dynamic risk assessment framework to ensure model outputs remain in sync with changing conditions.
Management strategies. The most critical question for any EWS is whether available information has saved lives and minimized damage to properties and livelihoods. In the case of coastal erosion, it is the latter, namely the loss of land and livelihoods and the need for relocation, that is of general concern. The risk information emerging from EWS will be helpful at different levels. For example, authorities can incorporate such erosion risk into their disaster management plans at the district and local levels, providing them with a basis for undertaking appropriate mitigation and preparedness measures. In the absence of such credible risk information, a large majority of vulnerable coastal districts in India find it difficult to make advanced planning that justifies investment in coastal protection measures. The same emerging risk can be communicated to local communities, serving multiple purposes such as raising their risk awareness and sensitizing them to the importance of environmental conservation, for example, that of mangroves and dunes.
Conclusion
India’s coastal management challenges are unique, and hence, the country should lead in exploring innovative solutions, such as EWS, without waiting for other countries. The available scientific and technical expertise, when combined with the necessary leadership, can indeed come together to create a Coastal Erosion Early Warning System (EWS), one that may well become a global achievement in climate change adaptation. It will help coastal communities and authorities by providing them with opportunities to take preventive and adaptive action rather than reacting when conditions become unmanageable, thus preventing the need for emergency relocation.
Notes
- Central Water Commission (CWC) (2020) Guidelines for “Protection and Control of Coastal Erosion in India”, National Institute of Oceanography (NIO). Accessed from CWC_Guidelines_Coastal.pdf
- Kankara, R.S., Murty, MV.R., Rajeevan, R. (2018) National Assessment of Shoreline Change along Indian Coast 1990-2016. schangenew.pdf (nccr.gov.in)
- Ministry of Road Transports and Highways (2022) Road Accidents in India 2022, Accessed from RA Draft.cdr
- Mishra, M., Acharyya, T., Guria, R. et al. (2024) Lightning-related fatalities in India (1967–2020): a detailed overview of patterns and trends. Environment Development and Sustainability. https://doi.org/10.1007/s10668-024-05276-z
- World Meteorological Organization (WMO) (2022) Early Warnings for All Executive Action Plan 2023-2027. Accessed from EARLY WARNINGS FOR ALL