India’s coastal cities need to brace up for super cyclones

The theme of this year’s world environment day centres on the issue of reimagining, recreating, and restoring our ecosystems. At a time when we could not afford it, the loss of ecosystems took away the world of carbon sinks such as forests and water bodies. Global greenhouse gas emissions have been on the rise despite the slower growth of economies the world over due to Covid-19.

Due to greenhouse gas emissions, global warming is already 1°C higher than the pre-industrial levels. There is vast evidence that this has serious consequences for ecosystems and human being. The IPCC’s special report on Oceans and Cryosphere (published in 2019) reveals that the ocean is 0.8 degrees warmer than the pre-industrial age. It is more acidic, and less productive because of the carbon emission that was sunk by the oceans.

The IPCC scientists referred to over 7,000 research papers published between 2014 and 2018 to conclude that the warming of oceans, a climate change event, will feed into more cyclones. The frequency and severity of these cyclones will increase manifold, states the report. Sea levels have risen because of melting glaciers and ice sheets, and harsh coastal conditions have worsened in recent years.

Increase in frequency and intensity

Cyclones are formed due to ocean heat-waves and the warming up of the oceans. The impact of ocean warming would be an increase in the frequency of tropical cyclone winds and rainfall, as well as an increase in extreme waves, all of which would be accompanied by a rise in relative sea level. These events aggravate coastal hazards as they feed into extreme events.

In the past couple of weeks, India experienced two pre-monsoon cyclones. Cyclone Tauktae was categorised as an ‘extremely strong’ cyclonic storm that hit west coast, particularity Maharashtra and Gujarat. The last time a similar level of devastation occurred was in 1998, that is, more than two decades back.

Cyclone Tauktae was followed by the ‘very severe’ Yaas in the end of May. It not only left a trail of devastation in Odisha and West Bengal but also made inroads into Ranchi and Jamshedpur in Jharkhand.

In 2020, cyclone Nisarga, categorised as severe, made landfall slightly away from the city of Mumbai. Cyclone Nisarga came just two weeks after cyclone Amphan, which was categorised as the first ‘super cyclone’ to have formed in the Bay of Bengal this century.

Although post-monsoon cyclones have been observed in the Arabian Sea, Nisarga and Tauktae are the first cases of pre-monsoon cyclones. The IPCC report shows that the number of cyclones in the Arabian Sea before and after the monsoon has increased over the years and is attributed to climate change.

Cyclone Nirohwa was the first ‘very strong’ cyclone recorded in the Arabian Sea in the 2014. In the following year, two other storms of same intensity, Chapara and Meg, were observed. In 2019, we had cyclones Kyarr and Mach. Kyarr was the first super cyclone recorded in the Arabian Sea during the monsoon.

The Bay of Bengal and the Arabian Sea generate only 7 per cent of the world’s cyclones. However, their impact are huge as some of the most densely populated regions of the world, including some mega-cities, are susceptible.

Coastal cities are at risk

India has one of the longest coastlines in Asia, running to 7,500 km. According to the 2011 Census, there are 486 census towns along the coast with a population of 41.7 million. A rough estimate shows that 20.7 per cent of the total coastal population lives in these towns.

Coral reefs, mangroves, tidal mudflats, seagrass beds, and salt marshes are some of the fragile habitats found along the Indian coastline. Apart from these ecosystems, the coastline features a variety of landforms such as sandy beaches, dunes, cliffs and rocks, among others. These ecosystems and geomorphological facets contribute to the protection of the coast and coastal communities. Over the years, these defensive forces against cyclones have been obliterated by various developmental processes and a lack of protection measures.

Several large cities such as Goa, Puri, Vishakhapatnam, Kochi and Puducherry, and mega-cities such as Kolkata, Mumbai and Chennai, are situated on the coastline. These cities are most vulnerable to the rising frequency and severity of the cyclones. To deal with these issues, the the government of India, in 2011, came up with Coastal Regulation Zone (CRZ).

CRZ rollout

The objective of CRZ was three-fold — to ensure livelihood security of fisher communities, conserve the coastal environment, and sustainably promote development via understanding the risks and hazards. In 2019, CRZ was updated to develop and manage the coastal regions on scientific principles, considering the current global challenge of climate change and sea-level rise.

CRZ was welcomed by stakeholders, but on the ground many things still need to be secured. One of them is coastal infrastructure. Due to the increase in climatic events, infrastructure such as roads, bridges, drainage lines and electrical wires need to be climate resilient to withstand winds generated by super-cyclones.

The government announced a package of infrastructure projects — as part of the Atmanirbhar Bharat, or a self-sufficient India, initiative — to revive the economy affected by the pandemic. Climate-resilient infrastructure is one of the key components of the ambitious infrastructural development programme.

However, it would take years for these projects to be completed and help the cities cope with the rapidly changing climate effects. Till then, if you are thinking of buying a sea-facing flat, think again!

The writer is Research Director at Bharti Institute of Public Policy, Indian School of Business.

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