Piping carbon back into the ground - carbon sequestration

In the battle to contain climate change, pumping carbon dioxide (CO₂) back into old coal seams or natural gas reservoirs has become one of the hot topics among scientific and government planners. Earlier this week, the idea was given a huge boost.

6. Some say that even a small chance of worldwide catastrophe is worth the “insurance” of working to reduce the risk to zero, even at astronomical expense. But how small is a “small” risk? And how does the risk of global warming stack up to the other global risks for which we could use our limited resources? That’s where I hit the wall on my understanding of the issue.