Taking issue with Canada's leaders and Alberta's provincial government, British Columbia's premier warns that the environmental risks of selling Canadian oil to Asia through the Northern Gateway pipeline would outweigh the economic benefits. [The Globe and Mail]

The Canadian oil and gas company Nexen agrees to be acquired by the China National Offshore Oil Company for $15.1 billion. The deal, which still faces a regulatory hurdle, is likely to be politically sensitive. [CBC]

Michael E. Mann, the Penn State climatologist, demands that The National Review publish a retraction of a blog post in which a writer compares the university's cover-up of Jerry Sandusky's actions to its inquiry clearing Dr. Mann of scientific misconduct. [Politico]

Alaska sues to block enforcement of federal rules intended to limit pollution from large ships, saying they will increase freight rates and cruise prices and hurt the state's economy. [Associated Press]

A Smithsonian scientist builds what is essentially a sperm bank for the world's corals, which are being damaged by acidification and global warming.