Table 2 |.
Modelled effects of adaptation and mitigation in reducing infrastructure damages
| Annual average costs in 2090 (billions of undiscounted 2015 US$) | ||||
|---|---|---|---|---|
| Sectora | Scenarios | RCP8.5 | RCP4.5 | Damages avoided by mitigation (RCP8.5 - RCP4.5) |
| Coastal property | Without adaptation | 120 | 92 | 26 (22%) |
| With adaptation | 7.3 | 5.7 | 1.6 (22%) | |
| Damages avoided by adaptation | 110 (94%) | 87 (94%) | 110 (95%) | |
| Roadsb,c | Reactive adaptation | 20 | 8.2 | 12 (59%) |
| Proactive adaptation | −7.3 | −3.1 | −4.2 (58%) | |
| Damages avoided by proactive adaptation | 27 (140%) | 11 (140%) | 23 (120%) | |
| Railb | Reactive adaptation | 5.5 | 3.5 | 2 (36%) |
| Proactive adaptation | 1.6 | 0.40 | 1.2 (75%) | |
| Damages avoided by proactive adaptation | 3.9 (71%) | 3.1 (89%) | 5.1 (93%) | |
a
Roads and rail include estimates for Alaska.
b
Damages due to delays or loss of infrastructure use (that is, indirect effects) are not included in these results and are the focus of future analysis.
c
Supplementary Section 3.2 contains additional information regarding proactive adaptation results for road infrastructure. The results represent averages across the five GCMs by sector. Values shown in bold represent the combined effects of reduced climate change (mitigation) and adaptation (difference in damage reductions between RCP8.5 without adaptation and RCP4.5 with adaptation). The values may not sum due to rounding.