Transitioning towards negative CO2 emissions

Highlights: • Mankind may need to achieve negative CO₂ emissions before 2050. • We describe a feasible transition to CO₂-neutrality and CO₂-negativity. • We illustrate the possibly critical role played in this transition by CO₂ use. • We recommend to step up RD&D efforts into a broad set of CO₂ use processes. -- Abstract: In this policy perspective we argue that mankind likely needs to achieve negative CO₂ emissions before 2050, describe the transition to CO₂-neutrality and CO₂-negativity, and illustrate the possibly critical role played herein by CO₂ use.