In small airports, like Vigra, where there only 1 or 2 airplanes stand, have roofs like carports to prevent snow on plane. This will reduce amount of deicing fluid needed.

Collecting data on past meal choices and preferences in combination with more sustainable meal offerings (plant/local) in a smart and sustainable packaging.

Incentivize sustainable behavior, e.g. a small reward for bringing your own coffee cup. This can also be sold by SAS in the Eurobonus store or in flight.

Meals included in the ticket fare are by default vegan (should be cheaper for SAS) and if meat dish is desired then it is a special order at an additional cost.

Recycling the deiceing fluid.

Go for a fast integration of programs, joint schedules to increase cabin factors in the SkyTeam system - so passengers stays in SkyTeam which will also benefit SAS.