Carbon dioxide sequestration isn't a great global warming solution unless we develop less leaky equipment or commit to regular re-sequestering, according to a paper published in Nature Geoscience. If the containers used don't leak less than one percent every thousand years, atmospheric carbon would have to be monitored carefully and resequestered on a regular basis over tens of thousands of years in order to match the effects of reducing carbon emissions. Otherwise, sequestration would only slow the warming, not stop it.

To study the long-term effects of carbon sequestration, Dr. Gary Shaffer modeled several scenarios and methods of storing carbon, both underground and in the ocean, as well as various combinations of the two.

He noted that current methods for both types of sequestration have leakages rate that are too high, and would only lead to a delayed warming of the atmosphere. According to his calculations, any method of sequestration would have to leak less than 1 percent of its volume every one thousand years in order to fully prevent global warming.

Dr. Shaffer notes that we could use leakier vessels if we committed to reharvesting the carbon every once in a while. However, this process would have to be kept up for tens of thousands of years in order to let the opportunity for warming to pass. In effect, to rely on carbon sequestration would necessitate tens of thousands of years of work and careful monitoring of a difficult-to-measure global leakage rate.

While Dr. Shaffer considered sequestration independently, it may be most effective if used in tandem with lowering carbon emissions in general. Still, his research suggests that at least some monitoring of any sequestration approach would be in order if we decide to commit to it, to ensure that the containers don't end up sneakily working against us.

Nature Geoscience, 2010. DOI: 10.1038/NGEO896 (About DOIs).