If humanity wants to have a 50-50 chance of limiting global warming to 1.5°C, we can only emit 250 another gigatonnes (billion metric tonnes) of CO₂. This effectively gives the world just six years to get to net zero, according to calculations in our new paper published in Nature Climate Change.
The global level of emissions is presently 40 gigatonnes of CO₂ per year. And, as this figure was calculated from the start of 2023, the time limit may be actually closer to five years.
