Is offsetting useful?
Offsetting can make a useful contribution to climate protection, but only under certain conditions. As a general rule, avoiding that the emissions come about in the first place is better than offsetting them. Not getting on a plane is better for the climate than purchasing carbon offsets. There are several reasons for this:
Offsetting is not a long-term solution: Offsetting is basically only a short- or medium-term measure to make flying less harmful to the climate. It does not change the fact that aircraft continue to emit climate-damaging emissions. To meet the climate goals of the Paris Agreement, global greenhouse gas emissions must be reduced to net zero over the next few decades. This means that every avoidable emission must actually be avoided. Remaining emissions must be offset by absorbing CO₂ from the atmosphere, e.g. through forests. These measures have only a limited potential, however, which must also be used to offset emissions from sectors like agriculture in which complete avoidance of greenhouse gases is not possible. To get a handle on the climate impact of flying in the long run, the long-term transformation of the aviation sector to carbon-neutral fuels and electromobility is therefore necessary. In order to initiate this transformation in time, appropriate (political) measures should be taken today – even if they are more expensive in the short term than offsetting.
Effect of carbon offsets on the climate: There are considerable uncertainties about the extent to which the purchase of an offset credit actually leads to a reduction of one ton of CO₂ elsewhere. If people fly less, however, the positive environmental effects are certain.
Rebound effects: If offsetting emissions through the purchase of carbon credits leads to more flying, it can even be harmful. Scientists refer to this phenomenon as a “rebound effect.” Some journeys would perhaps not be made at all or would be made with more environmentally-friendly means of transport if the option to offset emissions were not available. The idea of flying “climate-neutrally” by offsetting emissions is likely to play a role in some flight bookings. If more flights are taken than would otherwise have been the case, offsetting fails to achieve its goal.
Therefore, offsetting should always only be a last resort. However: if a flight is unavoidable, it is definitely better to offset the emissions than not.