The report, brought out by Greenpeace, an environmental organization, takes into account the growing greenhouse gas emissions. According to a report by BBC News, the study said that if global temperatures rise by about 4 - 5 degree Celsius in the course of the century - as they are projected to - the South Asian region could face a wave of migrants displaced by the impact of climate change.
Around 130 million people now live in India, Pakistan and Bangladesh in what are called low elevation coastal zones, which comprise coastal regions that are less than 10m above average sea level.
"Most of these people will be forced to leave their homes because of the sea-level rise and drought associated with shrinking water supplies and monsoon variability," said Dr Sudhir Chella Rajan, a climate expert and author of the study.
"The bulk of them will come from Bangladesh as most of the parts of that country will be inundated," he told the BBC.
According to Mohon Kumar Mondol, an activist from Bangladesh, that country is already experiencing the migration.
"Though Bangladesh is hardly responsible for the global warming and climate change, the Bangladeshi people are paying the price for it," he said.
The report said that the Indian coastline is also extremely vulnerable.
Several large cities within the low elevation coastal zone like Mumbai and Chennai will go under the sea if the present growth rate of greenhouse emissions continues, with new infrastructures being made along the coastline of these cities coming under the danger zone.
"This isn't going to happen gradually. What we are going to see is a series of coastal surges, you will see inundation, salt water intrusion - which will cause lots of harm and devastate a lot of these infrastructures," said Dr Rajan.
According to the Greenpeace report, major population movement from the coastal cities to other large urban centres like Delhi, Bangalore and Ahmedabad will take place.
"These cities will have serious resource constraints of their own by the middle of the century, but will have to be prepared to accommodate enormous numbers of migrants from the coasts."
In fact, the report predicts that the number of people who could be affected by climate change would be almost 10 times greater than the number of people who migrated during and after the partition of India in 1947.