Emission budgets and pathways consistent with limiting warming to 1.5 °C

Nature Geoscience (2017)

https://doi.org/10.1038/ngeo3031

We show that limiting cumulative post-2015 CO2 emissions to about 200 GtC would limit post-2015 warming to less than 0.6 °C in 66% of Earth system model members.

We combined a simple climate–carbon-cycle model with estimated ranges for key climate system properties from the IPCC Fifth Assessment Report. Assuming emissions peak then decline below current levels by 2030, we predict peak warming of 1.2–2.0 °C above the mid-nineteenth century. If CO2 emissions are mitigated over time to limit 2100 warming to 1.5 °C, net future cumulative CO2 emissions will range between 250-540 GtC.

Hence, limiting warming to 1.5 °C is possible but will require deep and rapid mitigation.