Effective CO 2 lifetime and future CO 2 levels based on fit function
The estimated global CO 2 emission rates and the measured atmospheric CO 2 concentrations show that only a certain share of the emitted CO 2 accumulates in the atmosphere. For given atmospheric emissions of CO 2, the effective lifetime determines its accumulation in the atmosphere and, consequently, its impact on the future global warming. We found that on average the inferred effective lifetime of CO 2 decreases as its atmospheric concentration increases, reducing the rate of its accumulation in the atmosphere. We derived a power function that fits the varying lifetimes. Based on this fitting function, we calculated the increase of CO 2 for different scenarios of future global emission rates.