
To have any chance of achieving the goal adopted in the Paris Agreement of stabilizing the global climate at less than 1.5°C above the pre-industrial average, humanity would have to become carbon neutral between 2050 and 2070 and show a negative carbon balance after that.
This was the assessment of the Intergovernmental Panel on Climate Change (IPCC) in its 2018 special report. The same conclusion was reiterated in its most recent report.