evidence: Greenhouse gas emission scenarios and the influence on future ozone. The influence of climate change on future ozone in Figure Q20-2 as discussed above was derived using a particular GHG emission scenario, termed RCP 6.0. Emission scenarios specify the amounts of GHGs emitted into the atmosphere in the future and are constructed based on socio-economic assumptions of future population growth, economic developments, technology innovation, and political decisions. The RCP 6.0 projection is a mid-range scenario with the abundance of CO2 and N2O increasing until the end of this century and the abundance of CH4 peaking in 2070. Chemistry-climate model simulations show that the evolution of ozone and the resulting surface UV-B levels in different regions of the world are strongly dependent on the future atmospheric abundances of CO2, CH4, and N2O, the three most important human-driven GHGs. [...] Links between stratospheric ozone depletion and changes in surface climate were first found in research studies in the early 2000s, based on both observations and models. While increasing greenhouse gases (such as carbon dioxide, methane, and nitrous oxide) are the primary drivers of global climate change, the Antarctic ozone hole, which has occurred every spring since the early 1980s, was shown to contribute to observed changes in Southern Hemisphere surface climate during summer due to its effects on atmospheric circulation.