When the Weatherbird II cruised up the Potomac River and into the nation's capitol in March of last year, spirits were high. The freshly painted 115-foot research vessel was about to set sail for what would be the world's first for-profit effort to "fertilize" the ocean with iron, growing a vast forest of marine plant life that would pull the greenhouse gas carbon dioxide from the atmosphere. The lap through Washington was an effort to drum up support for the voyage to the iron-deficient waters west of the Galápagos Islands.

Today's New York Times has a front-page story about how biofuels are driving up food prices around the world and how they therefore may not be a such a great idea after all. That could be true if the only feedstocks available for producing biofuels were food crops, as the article implies, but that's far from the truth.

Getting carbon dioxide out of the atmosphere is just one step. After plants and trees pull CO2 out of the air, some of the surplus carbon is funneled down into the soil, where it can then re-enter the atmosphere or seep into groundwater. To trap this excess carbon, Newcastle University scientists are trying to design new kinds of soils that would transform the stuff into calcium carbonate, keeping it down in the ground.

In recent months, PopSci has covered various scientists' plans to curb global warming through carbon sequestration, mainly by feeding it to algae to make biofuel, or burying it underground.

Today, a company called Skyonic announced a novel new system, Skymine, which uses the carbon dioxide emitted from smokestacks to make baking soda. According to Skyonic CEO Joe David Jones, the system will be powered by waste heat from factories, and will produce food-grade baking soda.

All top-secret government labs are either buried underground or hidden deep in a mountain. Everyone knows that, which is what makes the National Science Foundations recent announcement that it plans to convert the Homestake Mine, the deepest of its kind in the U.S., into a research facility, so surprising. How can it possibly be top secret if theyre telling everyone? The only answer, of course, is that they really are going to conduct legitimate research in astrophysics, biology and geology. The Homestake Mine, located in Lead, South Dakota, extends 8,000 feet down into the Earth and has over 375 miles of tunnels. It already has a rich scientific history: In 1965, physicist Raymond Davis led a team that set up the worlds first underground solar neutrino detector in a cavern deep in the mine, and eventually earned the Nobel Prize for his work. Scientists at the new lab will also pursue astrophysics research, along with work on carbon sequestration, organisms living in extreme conditions and geophysics. Over the next 30 years, two laboratories will be constructed. One will extend down to 4,800 feet, and the other will lie all the way down at 7,400 feet. Were guessing thats where theyll hide the aliens.—Gregory Mone

David Keith never expected to get a summons from the White House. But in September 2001, officials with the President's Climate Change Technology Program invited him and more than two dozen other scientists to participate in a roundtable discussion called "Response Options to Rapid or Severe Climate Change." While administration officials were insisting in public that there was no firm proof that the planet was warming, they were quietly exploring potential ways to turn down the heat.