Human activity is destabilising the Earth’s climate. A rise in global average temperatures is already having a significant impact on weather systems and society. Climate science tells us that if global average temperatures rise more than 1.5°C above pre-industrial levels, this impact could become catastrophic and potentially irreversible.

1 Special report: Global warming of 1.5°C, IPCC, 2018, www.ipcc.ch/sr15/.

To avoid such devastating impact, action is required now. Emissions reduction will be the main way to adhere to a 1.5°C pathway, but this alone is not enough. Negative emissions – achieved through technologies that actively remove CO2 from the atmosphere and store it long term – are an essential part of the solution. These technologies can neutralise residual, hard-to-abate emissions, draw down any emissions overshoot if emissions reductions are not delivered quickly enough, and remove historic emissions already in the atmosphere.

To limit warming to 1.5°C, multiple pathways state that the world needs negative emissions. Each of these pathways makes different assumptions on CO2 reduction and CO2 removals to meet 1.5°C, but all demonstrate that the short-term scale-up should be rapid (reaching around 1 Gt of negative emissions by 2030) and that the long-term need demands massive quantities (reaching around 5 to 10 Gt of negative emissions by 2050) - see Figure 1. Even pathways that rely on more ambitious reduction pathways agree that negative emissions are needed at the gigaton scale. For example the IEA pathway, which features more CCS use and faster reductions in transport and energy, still features around 4Gt of negative emissions by 2050.