In a recent paper in the journal Carbon Balance and Management (vol 3, p 1), Ning Zeng, an atmospheric scientist at the University of Maryland in College Park calculated that if we buried half of the wood that grows each year, in such a way that it didn't decay, enough CO2 would be removed from the atmosphere to offset all of our fossil-fuel emissions. It wouldn't be easy, but Zeng believes it could be done.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/burying-biomass-fight-climate-change
[2] http://admin.indiaenvironmentportal.org.in/category/author/richard-lovett
[3] http://admin.indiaenvironmentportal.org.in/category/journal/new-scientist
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/climate-change
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/climate-science
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/climate-mitigation
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/biomass
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-sequestration
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/united-states-america-us