By Joydeep Gupta, IANS
Bali : Over 10,000 delegates from 187 countries are attending the UN conference on climate change here to discuss ways to tackle global warming. What will happen if they do nothing, either now or later? What will be the effect of climate change on India, with nearly 700 million people directly dependent on climate-sensitive sectors such as agriculture, forests and fisheries for their livelihoods?
The answer is simple – disaster.
Srinivas Krishnaswamy of Greenpeace India says that as the sea level rises due to melting of ice around the world, “up to 120 million migrants from both Bangladesh and coastal India could end up in major cities in the interior of India, resulting in severe tensions and instability in a context of already dwindling urban resources.
“Additional damage worth trillions of dollars could be expected for coastal cities as their physical and social capital is lost to rising seas.”
The Greenpeace advisor lists the impact of climate change already here: “Droughts have become more common, especially in the tropics and subtropics, since the 1970s. The frequency of intense tropical cyclones has also increased and there has been widespread retreat of mountain glaciers. There has also been a rise in global sea level in the past century, with the most rapid rates of increase taking place in recent years.”
“India’s ecosystems such as river-sheds, mangroves, coastal zones, forests and grasslands are already over-burdened with environmental pressures from commercialisation, excessive resource use and the indiscriminate dumping of industrial and agricultural waste,” Krishnaswamy points out.
He quotes this year’s report of the Intergovernmental Panel on Climate Change (IPCC), which estimates that even under its most conservative scenario, sea levels in 2100 will be about 40 cm higher than today, which will cause an additional 80 million coastal residents in Asia alone to be flooded.
“The majority of those flooded will be in South Asia, particularly in Bangladesh and India. A one-metre sea level rise would result in nearly 6,000 square km in India being flooded, including parts of major cities such as Mumbai, Kolkata and Chennai.
“Sea level rise will affect the coastal zone in multiple ways, including the inundation and displacement of wetlands and lowlands, coastal erosion, increased coastal storm flooding and salinisation.”
He warns that rapid urbanisation has led to the enlargement of natural coastal inlets and dredging of waterways for navigation, port facilities and pipelines, all of which exacerbate saltwater intrusion into surface and ground waters.
Thus, built-up areas are more vulnerable than those protected by mangroves, and deltas, low-lying coastal plains, coral islands, beaches and barrier islands are especially at risk.
The Greenpeace advisor is not in favour of engineering solutions to the problem. He says “protection by dikes needs to consider not just the extent of average sea level rise but also the effect of more frequent and intense storm surges.
“Protection from sea level rise using engineering solutions is in any case not a viable option, especially for increases greater than a few tens of centimetres. One study estimated that the minimum cost of protection against a one-metre sea level rise would be about $500,000 per km, but even then about 20-50 percent of the vulnerable population would not be protected.”
In addition, says Krishnaswamy, the South Asian region will suffer from serious problems relating to water availability, substantial reductions in the yields of wheat and maize, increases in disease, flooding in some areas and drought in others, and potentially serious disruptions of the entire monsoon cycle.
Krishnaswamy again quotes this year’s IPCC report to say global warming may lead to “substantial changes in the timing of monsoon onset, its spatial distribution and the occurrence of ‘breaks’, that is to say, periods during the monsoon when there is no rain.”
The IPCC has estimated that the mega-delta of the Ganges-Brahmaputra is particularly at risk from climate change.
If cities such as Mumbai, Kolkata and Dhaka become uninhabitable due to sea level rise, “it is likely that large cities such as Delhi, Bangalore, Ahmedabad, Pune and Hyderabad, which will already have serious resource constraints of their own by the middle of the century, will have to be prepared to accommodate enormous numbers of migrants from the coasts”, he says.
However, adds Krishnaswamy, if the government takes urgent steps to reduce GHG emissions and can convince the rest of the world to do the same, the number of climate migrants from coastal areas can fall from 130 million to five million. It will not go down to zero, as the effects of climate change are already present.
(Joydeep Gupta can be contacted at [email protected])