Extended Data Fig. 2: Abatement costs and carbon debt of 1.5 °C (RCP 1.9) scenarios for six different MACCs of DACS and interest rates on carbon debt rd = 0 and rd = 0.08.
A definition of D is provided in the Methods. Abatement costs are discounted and expressed as a percentage of the GDP. Abatement costs are exclusive of interest costs. For each rate rd, 78 scenarios (13 scenarios as for the RCP 2.6 analysis times 6 DACS parameters) are grouped by DACS costs (low to high, that is, ‘LoCost’, ‘MedCost’ and ‘HiCost’) and DACS capacity limits (10% and 30% of baseline emissions, that is, ‘LoCap’ and ‘HiCap’). a, b, Median abatement costs as a function of median carbon debt D for rd = 0 (a) and rd = 0.08 (b). For rd = 0, we observe an inverse relation between the level of carbon debt and abatement costs; and the capacity limit is a stronger determinant of abatement costs than DACS deployment costs. This ‘discounting effect’ is reversed when rd = 0.08 and high levels of \(D\) are penalized. In this case, lower abatement costs are realized by lower carbon debt (and vice versa). For both rates rd ‘LoCost_HiCap’ DACS scenarios are characterized by the lowest abatement costs, however, at very different levels of D. When interest is invoked, DACS deployments costs become an increasingly important determinant of total abatement costs. c, d, Distribution of total carbon debt D (c) and abatement costs (d) for the median values shown in a, b. Boxes indicate the 25–75% interquartile ranges around medians (bold solid line), whiskers indicate minimum to maximum ranges, black dots mark outliers.
