As the seas continue to swell, they will swallow whole island nations, from the Maldives to the Marshall Islands, inundate vast areas of countries from Bangladesh to Egypt, and submerge parts of scores of coastal cities.

Eight years ago, as exclusively reported in The Independent on Sunday, the first uninhabited islands - in the Pacific atoll nation of Kiribati - vanished beneath the waves. The people of low-lying islands in Vanuatu, also in the Pacific, have been evacuated as a precaution, but the land still juts above the sea. The disappearance of Lohachara, once home to 10,000 people, is unprecedented.

It has been officially recorded in a six-year study of the Sunderbans by researchers at Calcutta's Jadavpur University. So remote is the island that the researchers first learned of its submergence, and that of an uninhabited neighbouring island, Suparibhanga, when they saw they had vanished from satellite pictures.

Two-thirds of nearby populated island Ghoramara has also been permanently inundated. Dr Sugata Hazra, director of the university's School of Oceanographic Studies, says "it is only a matter of some years" before it is swallowed up too. Dr Hazra says there are now a dozen "vanishing islands" in India's part of the delta. The area's 400 tigers are also in danger.

Until now the Carteret Islands off Papua New Guinea were expected to be the first populated ones to disappear, in about eight years' time, but Lohachara has beaten them to the dubious distinction.

Human cost of global warming: Rising seas will soon make 70,000 people homeless

Refugees from the vanished Lohachara island and the disappearing Ghoramara island have fled to Sagar, but this island has already lost 7,500 acres of land to the sea. In all, a dozen islands, home to 70,000 people, are in danger of being submerged by the rising seas.