In 2015, upon signing the Paris Climate Agreement, all nations around the world set themselves the goal of limiting global warming to below 2.0°C (preferably 1.5°C) compared to pre-industrial levels. Climate scientists now almost universally agree that once the 1.5°C limit is reached, our planet’s climate will experience irreversible and catastrophic changes. Humans have not faced such an existential threat for 75,000 years (when we nearly became extinct).
The IPCC Special Report on Global Warming concluded that the planet’s atmosphere can absorb no more than 420 gigatonnes (Gt) of additional CO2, if we are to stay below the 1.5°C threshold. Around 42Gt of CO2 is currently emitted globally each year (equal to 1332 tonnes per second) by human activity, which means that the 1.5°C budget is expected to be exhausted by 2028. Once we hit that threshold, there is no going back.
Use the Carbon Clock to check how much time is left.