Once one grasps what has been happening to land use and forest cover on the continent, it is much less surprising to come across direct measurements that suggest that North America is sinking more carbon than it emits. It is going back into the earth. One soda can's worth of carbon, back into every square yard of surface, every year. Enough, apparently, to sink back into the ground all the carbon we mine and drill out of it. Of course not.
Nothing continues forever.
But the massive deforestation brought about by our grandparents and great-grandparents has left enormous amounts of room for reforesting. In the Third World, which is still deforesting, the opportunities are even larger. Simply halt the deforestation, and we'd cut greenhouse emissions by almost 30 percent. Until quite recently, humanity's advance meant retreat for the wilderness. The more we grew, the more land we seized.