In Fig. , when sorbent degradation is not considered (left panel of Fig. ), the sorbent capacity remains constant, resulting in a constant rate of CO2 captured (i.e., there is a linear relationship between the amount of CO2 captured and sorbent lifetime). In contrast, when sorbent degradation is included (Fig. , right panel), there is a non-linear relationship between CO2 captured and sorbent lifetime as the sorbent's capacity decreases each cycle. Exponential capacity fade (firstorder deactivation) is used here as an example. In both scenarios, the sorbent carbon footprint is highest at short lifetimes due to the relatively small amount of CO2 captured. The carbon emissions associated with sorbent manufacturing and disposal are divided by the limited CO2 captured when the sorbent lifetime is short. As the sorbent lifetime increases before replacement, the carbon footprint decreases, regardless of whether or not the sorbent is degrading.