Mitigation Scenarios and Pathways

 ©Henrike Doebert / Climate Analytics
©Henrike Doebert / Climate Analytics

We explore the greenhouse-gas emission reductions necessary to achieve long-term global climate goals, such as holding warming below 1.5 and 2°C warming relative to pre-industrial levels. Analysing emissions scenarios from energy-economic models and other sources with coupled carbon-cycle/climate models leads to globally “allowed” ranges of emissions for different greenhouse gases, air pollutants and sectors, as well as associated time- and pathway-dependent mitigation costs and technology portfolios.


A pact by almost 200 nations to slash greenhouse gases used in refrigerators and air conditioners will likely fall short of governments' hopes of averting a full half-degree Celsius (0.9 Fahrenheit) of warming this century, scientists say. Michiel Schaeffer of Climate Analytics estimates "around 0.2 degree Celsius (0.36F) by 2100" of avoided warming.  


Limiting global warming to 1.5 or 2.0°C requires strong mitigation of anthropogenic greenhouse gas (GHG) emissions. Concurrently, emissions of anthropogenic aerosols will decline, due to coemission with GHG, and measures to improve air quality. However, the combined climate effect of GHG and aerosol emissions over the industrial era is poorly constrained. This study shows the climate impacts from removing present-day anthropogenic aerosol emissions and compares them to the impacts from moderate GHG-dominated global warming.