Enviros Challenge Dumping Urea in Ocean to Sink Carbon By Brandon Keim 11.07.07 12:00 AM http://www.wired.com/science/planetearth/news/2007/11/urea_dumping An Australian company is injecting urea into the ocean, hoping to sequester greenhouse-gas pollution and cash in on carbon credits. If all goes according to plan, oceanic plankton will thrive on the nitrogen-rich urea broth and absorb carbon dioxide. When the plankton die, they'll sink to the bottom of the sea taking the carbon dioxide with them. The business plan: Companies licensing the technology can sell carbon offsets. But some scientists worry the technique hasn't been rigorously studied. The nitrogen injections, they say, could feed toxic algae, disrupt poorly understood ecosystems and ultimately release more carbon dioxide than is deep-sixed. "If we're going to entertain such massive measures, they need to be informed by scientific fact and experimentation, and less by opinion and profit motivations," ...