English: Schematic showing the Paris agreement emission reduction targets.
The schematic was based on figure ES2 of page xvi/16 of The Emissions Gap Report 2016: A UNEP Synthesis Report See https://europa.eu/capacity4dev/file/31710/download?token=hOfXKoN6 The current policy target was extended to 2050 and cut in 2; one being the "past emissions" (data between 2010-2020) and the other half forming the current present policy target. The past emissions was taken from (the first part of) the current policy trajectory given that it included the emission reductions from earlier climate agreements (i.e. Kyoto protocol). Baseline is the data for if nothing would have been done between 2010-2020 (which wasn't the case) so this has been dropped entirely.
For the exact data used:
- past emissions: 48 (2010) to 53,5 (2020) gigatonnes of CO2 per year
- current policy trajectory: 53,5 (2020) to 70 (2050) gigatonnes of CO2 per year
- 2°C target: 53,5 (2020) to 23 (2050) gigatonnes of CO2 per year
- 1,5°C target: : 53,5 (2020) to 8 (2050) gigatonnes of CO2 per year
The 53,5 gigatonnes was calculated as follows:
48 gigatonnes was emitted in 2010, and 59 gigatonnes is to be emitted by 2030; so 59-48=11 over 20 years, so 5,5 over 10 years; 48+5,5=53,5
The 70 gigatonnes was calculated as follows:
48 gigatonnes was emitted in 2010, and 59 gigatonnes is to be emitted by 2030; so
59-48=11 over 20 years, so 22 over 20 years; 48+22=70