Figure 10.26. Fossil CO₂, CH₄ and SO₂ emissions for six illustrative SRES non-mitigation emission scenarios, their corresponding CO₂, CH₄ and N₂O concentrations, radiative forcing and global mean temperature projections based on an SCM tuned to 19 AOGCMs. The dark shaded areas in the bottom temperature panel represent the mean ±1 standard deviation for the 19 model tunings. The lighter shaded areas depict the change in this uncertainty range, if carbon cycle feedbacks are assumed to be lower or higher than in the medium setting. Mean projections for mid-range carbon cycle assumptions for the six illustrative SRES scenarios are shown as thick coloured lines. Historical emissions (black lines) are shown for fossil and industrial CO₂ (Marland et al., 2005), for SO₂ (van Aardenne et al., 2001) and for CH₄ (van Aardenne et al., 2001, adjusted to Olivier and Berdowski, 2001). Observed CO₂, CH₄ and N₂O concentrations (black lines) are as presented in Chapter 6. Global mean temperature results from the SCM for anthropogenic and natural forcing compare favourably with 20th-century observations (black line) as shown in the lower left panel (Folland et al., 2001; Jones et al., 2001; Jones and Moberg, 2003).