Sundarbans, a UNESCO World Heritage Site, spread across 20,000 square kilometres in India and Bangladesh, is threatened by rising sea level -- one of the most conspicuous effects of climate change. "You see, there we had a graveyard, it got washed off by sea waves... Then we made it there, but again it was submerged in water. Our homes were also swallowed by sea water. Where to go now?" 25-years-old Iftikhar says of Mousuni Island in the Sundarbans where he lives with over 2,000 others. Mousuni is one of the 102 islands on the Indian side of Sundarbans facing existential threat.