The carbon budget numbers in this film are based on the IPCC SR 1.5 report (released in Oct. 2018), stating that on Jan. 1, 2018, we had 420 Gt CO2 left to emit globally to have a 67% chance of staying below the 1.5°C global warming target.
We emit about 42 Gt CO2 every year—so when this film was completed in Summer 2021, the remaining carbon budget was between 277-273 Gt CO2. Therefore, Greta says:
“Today, the world is down to lower than 280 Gt CO2 left. That is the equivalent of less than six and a half years of today’s business-as-usual emissions until that budget completely runs out.”
On Aug. 9, 2021, the IPCC WG1 AR6 report was released with updated carbon budget numbers, stating that at the beginning of 2020:
To have a 67% chance of staying below 1.5°C, the world had 400 Gt CO2 left.
To have an 83% chance of staying below 1.5°C, the world had 300 Gt CO2 left.
The 67% chance numbers now give us about 1 year more than stated in this film. The 83% chance numbers give us about 1 year less to drastically change course.
We locked the film with the SR 1.5 numbers, so we kept it that way—which roughly splits the difference. Either way, the clock is ticking and we have precious little time left.
