There can also be no debate, at this point, that the melting of the Antarctic and Greenland ice caps is driving a rise in sea levels, which the National Oceanic and Atmospheric Association and others have warned will worsen coastal flooding in the coming years, threatening cities such as New York, Miami, Philadelphia, Houston, Fort Lauderdale, Galveston, Boston, Rio de Janeiro, Amsterdam, Mumbai, Osaka, Guangzhou, and Shanghai. A billion people or more live in areas likely to be affected by rising sea levels.
