Air New Zealand has appointed Kiri Hannifin as its chief sustainability officer, a newly created role as the airline places an increased focus on addressing its environmental impact.

Hannifin will join the airline on December 5 from Countdown, where as director of corporate affairs, quality, health & safety and sustainability she spearheaded the company's programme to reduce emissions, managed the health, safety and wellbeing of the company's 21,000 staff.

Air New Zealand chief executive Greg Foran said sustainability is the biggest issue facing the airline's future and requires increased focus from a leader who will be a passionate public advocate for the changes all stakeholders need to make to deliver real change.

"As we rebuild Air New Zealand, we need to advance the extensive work already undertaken to become a truly sustainable airline," Foran said.

"Kiri's experience in driving change across the supply chain, engaging customers via tangible measures such as removing plastic bags from stores and diverting food waste from landfill will help our efforts move to a new level."

The signing of a Sustainable Aviation Arrangement (SAA) between New Zealand and Singapore could see "green-lane flights" between the two countries in the future.

A Sustainability Report released last year by Air New Zealand revealed a worrying number amid flying during the pandemic.

While passengers may have been enjoying flying in some half-full cabins, light loads on Air New Zealand flights have been bad for the planet.

Despite a steep 58 per cent drop in total network emissions compared with pre-Covid times, flying is less environmentally efficient per passenger.

The key measure of carbon intensity - measured by grams per tonne of payload carried - was up 31 per cent in 2021, compared to 2020.

"This increase was largely due to New Zealand border restrictions leading to lower than usual load factors on the international network and multiple national lockdowns impacting load factors on the domestic network," the report said.