Historical responsibility for climate change is at the heart of debates about climate justice . History matters because the cumulative amount of carbon dioxide (CO2) emitted since the beginning of the Industrial Revolution is closely related with 1.2 °C of warming, to which already happened . In total, humans have pumped into the atmosphere since 1850 approx 2,500 billion tonnes of CO2 (GtCO2), leaving less than 500 Gt of CO2 remaining   carbon budget , to stay below 1.5°C of warming. This means that by the end of 2021 the world will collectively burn 86 % of the carbon budget with a 50-50 chance of staying below 1.5°C, or 89 % of the budget with a two-thirds chance. (SIMON EVANS, Carbon Brief)