An aviation commentator says there is little New Zealand can do about the impacts of emissions on the Pacific.
Peter Clark's comments follow a study at the Massachusetts Institute of Technology that found aviation emissions affect the Pacific atmosphere more harshly than anywhere else in the world.
The emissions contain nitric oxide and nitrogen dioxide, which create ozone when released into the atmosphere.
The study says flight routes across the Pacific cause abnormally high amounts of ozone because its clean atmosphere reacts more severely to the aircraft emissions.
Most sensitive to this reaction is an area 1000 kilometres north-east of Solomon Islands, in which emissions produce up to five times more ozone than European regions.
Mr Clark says it is unlikely there is more action the aviation industry could take to cut emissions.
"We have the most modern fleet, we are moving into more modern fleets. Those fleets will have some of the best engines in the world with the least emissions of any engine that is available. So look, I think it's unrealistic to think that we can do anymore except take aircraft out of the air"