Agence France-Presse: When a cyclone destroyed her home two years ago, Shahana Begum joined the swelling ranks of Bangladeshi “climate refugees” who, experts say, could one day overwhelm the capital Dhaka. Shahana’s family, like more than half a million people in the impoverished nation, lost her shanty home and all her belongings when cyclone Sidr slammed into southern Bangladesh in November 2007, claiming more than 3,500 lives. “I moved to Dhaka because there was nowhere else to go,” said Shahana, …