In M class on Intercontinental flights reduce the usage of plastics, ask the passenger to keep their glass for the entire flight before collecting it for recycling.

For every mile the aircraft flies overseas, SAS commits to a certain amount of plastic being removed from that ocean.

Discount on available seats if booked 5 hours before departure to fill up empty seats

Upgrade the lounge kitchen and and hire a chef to make the flight food on the airport instead of having it delivered to the airport

SAS should incentivize off-peak flights. Lower ticket prices on empty aircraft will reduce peak demand and the emissions caused by congestion and delays.

Bio fuel / green fuel as default, and having to pay more as a passenger if you want to fly on fossil based airplane fuel.