Tracking down CO2

Carbon Detectives Are Tracking Gases in Colorado - NYTimes.com

Good article explaining the research underway to get a better understanding of where CO2 comes from and goes (otherwise known as the carbon budget):

...researchers think about half of the CO₂ emitted into the atmosphere gets absorbed by oceans and land, but they do not know precisely where the gases come from and where they end up. This knowledge gap has serious policy implications; until it becomes clear where emissions are going, it will remain difficult to have verifiable credits for sequestering carbon.

“We need to make sure that carbon markets are affecting climate change, not just putting money in the hands of some companies and people,” said Lisa Dilling, an assistant professor of environmental science at the University of Colorado, Boulder.

A vexing challenge is that surface inventory assessments — based on measuring forests, agricultural fields and smokestack emissions, for instance — generally do not agree with atmospheric measurements.

This sounds like it may help a lot:

In January, the next frontier of atmospheric CO₂ measuring instruments will begin when the National Aeronautics and Space Administration launches the first carbon-scanning satellite, called the Orbiting Carbon Observatory.

Each day, the satellite will orbit Earth 15 times, taking nearly 500,000 measurements of the “fingerprint” that CO₂ leaves in the air between the satellite and Earth’s surface. The data will be used to create a map of CO₂ concentrations that will help scientists determine precisely where the sources and sinks are — showing differences in trace gases down to a 1 part per million precision against a background of 380 parts per million CO₂ equivalent.

Surprising they haven't had a satellite to do that before now.