A new computer modeling study confirms that global warming is changing the salinity of seawater in the North Atlantic.

Reconstructions of ancient atmospheric carbon dioxide (CO2) variations help us better understand how the global carbon cycle and climate are linked. We compared CO2 variations on millennial time scales between 20,000 and 90,000 years ago with an Antarctic temperature proxy and records of abrupt climate change in the Northern Hemisphere.

Rising tropical sea surface temperatures alter atmospheric dynamics at heights of 16 kilometers or more.

Preliminary data from two Arctic cruises suggest that rising temperatures are already causing substantial amounts of methane to be released from beneath the ocean floor. But catastrophic gas leaks, like those believed to have occurred 55 million years ago, are unlikely, scientists say.

“Wasteland” conjures up visions of dusty desolation where life is fleeting and harsh—if it exists at all. Oceans, too, have their inhospitable pockets. Scientists are discovering that climate change—and not just fertilizer from farm use—may be spurring the emergence of barren underwater landscapes in coastal waters. Expanding dead zones not only spell trouble for biodiversity, but they also threaten the commercial fisheries of many nations.

Predicting the ocean