Figure 3.

Not all climate variables respond to solar geoengineering the same way. The global-mean temperature (a), global mean precipitation (b) and tropical aragonite saturation state (c) are shown for the cases in figure 2: RCP8.5 (BAU), RCP4.5 (+mitigation), RCP4.5 augmented with long-term CO₂ removal (+CDR) and RCP4.5, CDR, and sufficient solar geoengineering to maintain temperature at 1.5°C (+SRM). SRM acts quickly while CDR acts slowly: in this scenario, the compensation of climate change due to CO₂ emissions is primarily due to SRM in 2100; by 2200 both SRM and CDR contribute. Temperature and precipitation responses are estimated from median of 12 models participating in GeoMIP and aragonite saturation state responses are estimated from Kwiatkowski et al. [94] (see appendix A; the electronic supplementary material). (Online version in colour.)