Three of the world's heaviest polluters will likely face the greatest human and financial costs caused by coastal flooding, one of the effects of climate change.

According to a report released Monday by Christian Aid , an anti-poverty organization, people living in the U.S., China and India -- three of the world's very worst offenders in terms of greenhouse gas emission -- face the greatest risks posed by coastal flooding.

By 2060, more than a billion people worldwide will likely confront coastal flooding due to sea level rise, storm surges and extreme weather, with the majority of those people living in major cities throughout Asia.

Calcutta, India, tops the list, where around 1.3 million people are currently exposed to coastal flooding. By 2070, that number is expected to balloon to 14 million, according to the report. Mumbai ranks second, where an estimated 11.4 million people could face disruption due to flooding by 2070. Dhaka, Bangladesh, is third with a projected 11.1 million vulnerable people.