Climate changes, flooding out and drying up in Southasia

This past summer a calamity of a scale never before seen in Southasia inundated large parts of India, Nepal and Bangladesh, killing more than 2000 people and displacing some 20 million. UNICEF estimates that Bangladesh was the hardest hit, with nearly 880 people killed and more than 36 million people – a quarter of the population – affected. The floods ended up destroying bridges, schools and roads, and shattering livelihoods for tens of thousands as the waters swept away summertime crops. Several Himalayan rivers burst their banks in the Nepal Tarai, as well as across the border in Bihar and Uttar Pradesh. But even after the waters receded, Bangladesh's weather-related tragedies were not over for the year. In November, Cyclone Sidr, a 'category-four' storm, swept furiously through the country – flattening houses, damaging buildings and roads, and again destroying thousands of acres of crops. Thousands of people died, and approximately 27 million people were affected – many for the second time in six months.

While Southasia has long been used to the annual flooding of the monsoon, the intensity and unpredictability of the region's rains is becoming striking, for lay and scientific observers alike. Indeed, it is unlikely that anyone will soon forget the cataclysmic scenes surrounding the Bombay floods of 2005, when unprecedented rainfall measuring 944 millimetres in just a single day brought India's financial hub to a complete standstill. The city seemed hardly better prepared: Bombay's dilapidated sewer system turned streets into rivers, leading to more than 1100 deaths and losses estimated at more than USD 250 million. The country's previous single-day record for rain had been back in 1910, when 838 mm fell in Cherrapunjee in July of that year.