On climate, a fraught Plan B: Carbon capture helps, but not enough

If a tree that falls in the forest is fed into a power plant, and the carbon emitted is captured and stored, is it helping to save the planet?

Under United Nations carbon accounting rules, it would be: Provided the tree is replaced, the entire process takes more heat-trapping carbon out of the atmosphere than it puts in.

This and other experiments in carbon removal and storage offer leaders at the U.N. Climate Change Conference here a morally fraught Plan B: If they fail to reduce carbon emissions sufficiently to curb disastrous global warming, then they attempt to make nature or technology