Depending on levels of GHG mitigation, modelled emissions scenarios based on the SSPs can be consistent with low or high warming levels104. 
There are many different mitigation strategies that could be consistent with different levels of global warming in 2100 (see Figure 4.1). 
{WGI Box SPM.1; WGII Box SPM.1; WGIII Box SPM.1, WGIII Box TS.5, WGIII Annex III; SRCCL Box SPM.1, SRCCL Figure SPM.2}
WGI assessed the climate response to ﬁve illustrative scenarios based on SSPs105 that cover the range of possible future development of anthropogenic 
drivers of climate change found in the literature. These scenarios combine socio-economic assumptions, levels of climate mitigation, land use and 
air pollution controls for aerosols and non-CH4 ozone precursors. The high and very high GHG emissions scenarios (SSP3-7.0 and SSP5-8.5) have 
CO2 emissions that roughly double from current levels by 2100 and 2050, respectively106. The intermediate GHG emissions scenario (SSP2-4.5) 
has CO2 emissions remaining around current levels until the middle of the century. The very low and low GHG emissions scenarios (SSP1-1.9 and 
SSP1-2.6) have CO2 emissions declining to net zero around 2050 and 2070, respectively, followed by varying levels of net negative CO2 
emissions. In addition, Representative Concentration Pathways (RCPs)107 were used by WGI and WGII to assess regional climate changes, 
impacts and risks. {WGI Box SPM.1} (Cross-Section Box.2 Figure 1)
In WGIII, a large number of global modelled emissions pathways were assessed, of which 1202 pathways were categorised based on their 
projected global warming over the 21st century, with categories ranging from pathways that limit warming to 1.5°C with more than 50% 
likelihood108 with no or limited overshoot (C1) to pathways that exceed 4°C (C8).