Above ground biosphere currently contains about 500 gigatons of carbon, while fossil fuel emissions are about 10 gigatons per year. So doubling the number of trees on earth would buy us less than 50 years of burning oil at the current rate. (This is a gross simplification as the above ground biosphere is in equilibrium with the atmosphere and the soil, but it still gives an idea of the magnitudes involved). I would not call the herculean effort needed to plant that many trees easy or cheap. Maybe we should just reduce emissions instead?
Above ground biosphere currently contains about 500 gigatons of carbon, while fossil fuel emissions are about 10 gigatons per year. So doubling the number of trees on earth would buy us less than 50 years of burning oil at the current rate. (This is a gross simplification as the above ground biosphere is in equilibrium with the atmosphere and the soil, but it still gives an idea of the magnitudes involved). I would not call the herculean effort needed to plant that many trees easy or cheap. Maybe we should just reduce emissions instead?