NatureNews - Earth and Environment - nature.com science feeds Nature - the world's best science and medicine on your desktop Seven billion and counting A look behind this month's global population landmark reveals a world in transition. A struggle for power Brazil is developing the last great untapped reserve of hydroelectricity, the Amazon basin. Greenland ice-melt map gets the cold shoulder Polar researchers mobilize to clear up atlas's icesheet error. Military surveillance data: Shared intelligence The military has a vast array of scientifically valuable data — some more accessible than you think. Redrawing the Arctic map: The new north Getting to grips with a changing polar landscape. Climate and weather: Extreme measures Can violent hurricanes, floods and droughts be pinned on climate change? Scientists are beginning to say yes. Special issue on the Arctic: After the ice As the Arctic thaws, can science help to chart a sustainable path for the north? Scientific challenges in the Arctic: Open water As the ice melts, fresh obstacles confront Arctic researchers. Canada's ice cores seek new home Confusion over fate of valuable climate record chills researchers. Seth Stein: The quake killer The US government says that a huge earthquake risk lurks in the heart of the country, where a series of large shocks hit 200 years ago. Seth Stein says that kind of warning is dead wrong. Brazil cooks up transgenic bean Approval draws criticism over transparency and safety tests. Dam controversy: Remaking the Mekong Scientists are hoping to stall plans to erect a string of dams along the Mekong River. Scientists push for agricultural monitoring Network would collect environmental and socioeconomic data from around the world. Nitrogen pollution disrupts Pacific Ocean Surging nitrates in Asian waters could dramatically affect marine wildlife. Angry words over East Asian seas Chinese territorial claims propel science into choppy waters.