The carbon offset scam
This very interesting video from Deutsche Welle, Germany's equivalent of the BBC (don't worry, it's in English) explains what carbon offsets are, and how many of them are scams. For example, you buy a carbon offset which funds protection of a natural forest. And 10 years later the forest has been cleared. Does the offset scheme get its money back? Fat chance. Or a planted forest gets burnt down, and all the embedded carbon is re-released into the atmosphere. Or offset money is used to build new wind and solar farms, but they were going to be built anyway. Something like 85-90% of offsets actually do not reduce emissions at all.
But some are good. The rewilding of marshland that the video starts off with is a real offset. The scheme in Iceland for turning carbon into rock is real: carbon dioxide is permanently removed from the atmosphere. But most are fake.
The video concludes with 3 useful points. First, if it's a real carbon offset, it'll prolly be expensive. Second, we will need real carbon offsets in the future to keep temperatures from rising past 1.5 degrees above pre-industrial levels. Third, we can't offset our way to zero emissions. We have to actually cut emissions, by replacing petrol/diesel cars and light trucks with EVs; by switching to renewables electricity generation; and by using green hydrogen or methane in industrial processes.