A scary scenario awaits India and the coastal cities of Mumbai, Kolkata and Chennai if global temperatures rise, as projected, by about 4-5 degrees in this century.
<b1>About 75 million people from Bangladesh would migrate to India as climate change, rise in sea levels, drought, shrinking water supplies and monsoon variability takes a toll on coastal states and regions. In all, about 125 million migrants, including 50 million from densely populated coastal regions and other vulnerable parts of India, could become homeless.
The scale of migration would be equivalent to the Partition ten times over. It would displace 375 times the number of people needing rehabilitation from the Sardar Sarovar project.
This is the grim picture painted by S Chella Rajan, a professor at IIT Chennai, in his report titled Climate Migrants in South Asia: Estimates and Solutions if the country continues to follow the current “business-as-usual’’ approach and fails to take policy interventions to check the impending crisis.
Greenpeace, an independent environment watchdog, released the report on Tuesday.
Rajan said the impact of greenhouse gas emissions and climate change would be immediately felt by almost 130 million people in India, Bangladesh and Pakistan who live in the Low Elevation Coastal Zone of less 10 metre above average sea level. The fate of Mumbai, Kolkata and Chennai that are at average elevations of 2-10 meters would hang by a thread.
He quoted a study by an intergovernmental panel on climate change which said a one metre rise in the sea level would result in nearly 6000 sq km in India being flooded, including parts of Mumbai, Kolkata and Chennai.
Rajan warned that unless drastic action is taken, climate change and the rise in sea level would trigger major population movements to other large urban settlements in the interior rather than to smaller cities on the coastline and by the middle of the century, put already burdened cities like Delhi, Bangalore, Ahmedabad, Pune and Hyderabad under further strain.
Migration would be heavy from West Bengal (10 million), Maharashtra (10-12 million), Tamil Nadu (10 million), Andhra (six million), Gujarat (5.5 million) and Orissa (4 million).
The report estimates eight million rural migrants would head for urban areas because of double exposure to climate change and the effects of globalisation. It cited a study that identified the vulnerable areas as western Rajasthan, south Gujarat, Madhya Pradesh, Maharashtra, north Karnataka, Andhra and south Bihar.
“India cannot afford to sit back and allow the climate crisis to drive millions of its people homeless. The business as usual approach would displace 125 million people while if global and local policy interventions contained global warming below the 2 degree Celsius limit, the number of migrants would be about five million people. There is no question that rehabilitation of 125 million people is simply not possible,'' said Rajan.
Within the next 50 years, he warned, there will be more heat waves, higher summer temperatures and fewer cold winters. India, he said, has no option but to seek policy options that involve adopting an economic growth path that moves towards decarbonisation. More so, because the costs of adapting to climate catastrophe are not in the realm of what is possible.
One study estimated the minimum cost of protection against one metre sea level rise would be about $500,000 per km but even that wouldn’t be able to protect 20-50% of the vulnerable population.