A suggestion to fill all car tyres worldwide with carbon dioxide (CO2) to reduce atmospheric carbon would not yield a significant impact, according to reader replies to a question posed by Chris Coldwell of Lancaster in The Guardian.
Calculations indicate that if all 1.5 billion cars on the planet had their tyres filled with CO2, approximately 157,700 tonnes of CO2 would be stored. This figure is minimal when compared to global CO2 emissions, which reached 38.1 billion tonnes in 2025.
Concerns were also raised about the practicality and safety of such a measure. CO2 is reported to leak from rubber more quickly than nitrogen, potentially leading to underinflated tyres and requiring frequent pressure checks. Additionally, the infrastructure for compressing and storing high concentrations of CO2 everywhere could pose safety risks, as CO2 at levels above 2% in air can be problematic.
The cost of collecting, transporting, and storing CO2 for this purpose would likely be substantial. Furthermore, the CO2 would be released back into the atmosphere when tyres are punctured, wear out, or are removed.