The sequestration of atmospheric CO2 by the land surface is important because it would determine the reasonable goal of reducing fossil fuel emissions, which is at a rather high economic cost.
(The sequestration of atmospheric CO2 by the land surface; is; important; because it would determine the reasonable goal of reducing fossil fuel emissions) (it; would determine; the reasonable goal of reducing fossil fuel emissions) (fossil fuel emissions; is; at a rather high economic cost)
The sequestration of atmospheric CO2 by the land surface it fossil fuel emissions
is would determine is
important because it would determine the reasonable goal of reducing fossil fuel emissions
the reasonable goal of reducing fossil fuel emissions
at a rather high economic cost