To ensure a habitable planet for all, we must reduce carbon emissions to achieve ‘net-zero or less’ greenhouse gas emissions to limit global overheating to 1.5 degrees centigrade.
We currently emit over 50 GtCO2e every year, and to achieve this goal that we must reduce this to zero before 2050. In the meantime, the world has already warmed by over 1C, and going over 2C warming may lead to runaway overheating effects.
To have a likely chance (67 percent), of limiting warming to 1.5°C, the world can emit 570 gigatonnes of carbon dioxide (GtCO2).
The bad news is that, in the absence of external cooling influences, such as volcanic eruptions, the midpoint of the spread of temperature projections exceeds the 1.5°C target before 2029, based on temperatures relative to 1850–1900.
From any sensible risk-management point of view — where special concern is given to the high-end and most devastating possibilities, not the middle-of-the-road probabilities — there is no carbon budget left for the Paris targets.
The good news is that innovative solutions to drawing down carbon are advancing rapidly, while the fossil fuel industry (coal, oil and gas) is rapidly becoming obsolete as renewable energy is now much cheaper, and electric and hydrogen-powered transport solutions are growing rapidly.