Infographic: How are carbon offsets supposed to work?
Carbon offsets can be purchased by companies, governments or individuals seeking to meet a net-zero target or simply make a contribution to tackling climate change.
This process is often presented as a simple transaction in which paying for the offset directly leads to, say, trees being planted or wind turbines erected.
In reality, a complex system of project developers, auditors, registries and third-party suppliers stands between the buyer and the emissions-cutting project.
Theoretically, the offsetting arithmetic is simple, with an emissions increase in one place cancelled out by an emissions reduction somewhere else. But, along the way, there are plenty of opportunities for errors – intentional or otherwise – to creep in.