I wonder how practical it would be to add something smelly and distinctive to CO2 the way we do with natural gas? Otherwise a CO2 leak is really mysterious. It could be in quite low concentrations, to the point where you would only smell it if the air was getting to dangerous levels. This wouldn't help with a release from a natural source, but if we are ramping up carbon capture efforts maybe we'll see more industria…
could be harder to find something that sticks with the CO2 given the molecule sizes? CO2 is also relatively easy to monitor, so sensors + awareness of people living/working nearby should also cover a lot. But both of course only would give better warning, not solve the challenge of dealing with the situation when it has happened.
And yet we inexplicably don't monitor it at all. You can download apps to show you national and local levels of all sorts of pollutants... but not CO2. Outdoor CO2 is tracked at a single point on the Mauna Loa Observatory in Hawaii... and that's pretty much it.
It's bizarre. It's easy to buy an indoor CO2 monitor (I use one to determine when I should open my windows more/less to keep the air inside fresh), but at a local/national monitoring level it simply doesn't exist.