"Fig-SPM.1 Reference and Stabilization Scenarios
for Global Anthropogenic CO2 Emissions (GtC)

The figure is divided into six parts, one for each of the reference scenario groups from the Special Report on Emissions Scenarios (SRES, see Box SPM.1). Each part of the figure shows the range of total global CO2 emissions (gigatonnes of carbon (GtC)) from all anthropogenic sources for the SRES reference scenario group (shaded in grey) and the ranges for the various mitigation scenarios assessed in the TAR leading to stabilization of CO2 concentrations at various levels (shaded in colour).

A1 - Rapid Global Growth Scenario

A1B - The Balanced Scenario

A1T - The Non-Fossil Fuel Scenario

A1FI - The Fossil-Fuel Intensive Scenario

A2 - Regional Growth Scenario

B1 - Global Service Economy Scenario

B2 - Increasing Population Scenario

Figure SPM.1: Comparison of reference and stabilization scenarios. Scenarios are presented for the A1 family subdivided into three groups (the balanced A1B group (Figure SPM.1a), non-fossil fuel A1T (Figure SPM.1b) and the fossil intensive A1FI (Figure SPM.1c)) with stabilization of CO2 concentrations at 450, 550, 650 and 750 ppmv; for the A2 group with stabilization at 550 and 750 ppmv in Figure SPM.1d, the B1 group with stabilization at 450 and 550 ppmv in Figure SPM.1e, and the B2 group with stabilization at 450, 550 and 650 ppmv in Figure SPM.1f. The literature is not available to assess 1000 ppmv stabilization scenarios. The figure illustrates that the lower the stabilization level and the higher the baseline emissions, the wider the gap. The difference between emissions in different scenario groups can be as large as the gap between reference and stabilization scenarios within one scenario group. The dotted lines depict the boundaries of the ranges where they overlap."

Source & © : IPCC TAR SPM of WG III