Professor Quentin Atkinson is used to flying - a lot.
For the University of Auckland academic, a given year might include a few trips to Europe, to Asia and North America, and to his study field site in Vanuatu.
Then there are the many, many more flights he makes around the country to visit collaborators or sit on national committees.
"The problem with all this air travel is that flying is about the most carbon-intensive way you can spend your money."
He pointed out that one flight from Auckland, per passenger, produced nearly as much CO2 as the average New Zealander did in a year.
When he calculated his carbon footprint, he was blown away; up to 90 per cent of it was from flying.
So he decided to make a change. Last year, he joined colleague Professor Shaun Hendy in staying on the ground for 12 months.
That meant skipping international conferences and swapping any other overseas meet-ups for Skype or Zoom sessions.
"This felt like a big deal for two academics based in New Zealand - presenting ideas at conferences and staying plugged into international networks is crucial to academic success, and we were going to give all that up for a whole year."
Just travelling around New Zealand by train, bus or low-emission private vehicle proved tough enough – but the pair pulled it off, and slashed their annual CO2 output by at least 80 per cent.
Atkinson said the feat also pulled him back down to earth, in the other sense.
"I loved not flying. I loved getting the train to Wellington, watching the Central Plateau drift by while I graded papers. I loved not spending days - literally days - of my year in airport transit lounges. I loved having more time with my family because I just travelled less.
"I loved exploring local holiday options and deciding to holiday locally with my family, rather than fly away to somewhere I have no real connection with.
"And I realised that it is not imperative that I spend much of my year preparing for, conducting or recovering from international travel."
Globally, it's estimated that aviation contributes to about 3.5 per cent of human-driven emissions, and it's been projected that, by next year, the impact would have grown 70 per cent from 2005 levels.
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But Kiwis love to – and quite often need to – hop on a plane. In 2017, New Zealand residents departed on 2.83 million trips overseas, up 271,800 on the year before.
And our largest export industry – tourism – relies upon international travel. The $39 billion it reaped last year wouldn't have been possible had not 3.82 million visitors arrived on our shores.
Air New Zealand, conscious of the carbon footprint it leaves flying people halfway across the world, is trying to limit its impact through different ways. One is committing to the global industry's goal of halving net emissions, relative to 2005 levels, by 2050.
It's tried to strip out carbon emissions through a reduction programme it launched in 2016. It also enables passengers to pay to offset their emissions - an approach the Government this week released voluntary guidelines on for other companies to use.
That's not to say aviation isn't the only part of the transport sector struggling to rein in its CO2 pollution.
The latest figures showed New Zealand's gross emissions jumped 2.2 per cent between 2016 and 2017 – and one of the biggest increases among the data was the 6 per cent bump, or 863 tonnes of CO2 equivalent, chalked up by road transport.
In all, transport made up 20 per cent of the country's total emissions – and also represented about 40 per cent of the energy sector's.
Government measures to specifically address transport emissions include a "feebate" scheme to clean up our ageing vehicle fleet, and investing about $14b in public transport, cycleways and walkways.
But that all hit up against emissions that would come from rising tourism, with the sector this year launching its biggest ever campaign – interestingly predicated, again, on the 100 Per Cent Pure brand – and amid a goal of becoming a $50b industry within six years.
Atkinson said tackling New Zealand's transport emissions, and those from everywhere else, shouldn't be framed as a sacrifice.
"Must we give up flying? Must we give up our cars in favour of public transport or cycling?
"Must we give up meat? Milk? All manner of cheap consumer goods and comforts? Who decides what we must do and what right have they to do so?
"But this framing blinds us to the fact that, almost invariably, for everything we are asked to give up, there exist equally good, perhaps better alternatives that we likely haven't even considered. We confuse new opportunities for sacrifice."
"Of course, some New Zealanders are less well equipped to deal with the required changes than others, and for some, the changes required could be costly. But most of us are not significantly affected by this.
"If we fail to act on climate change now and continue to delay meaningful action, then we will indeed all have to make choices that involve sacrifice. Real sacrifice.
"But right now, for the majority of us, the road to tackling climate change remains smooth enough that almost everything we are being asked to change is not a real sacrifice in the true sense of the word, it is just different."
• People can order Professor Shaun Hendy's book about his year of not flying, titled #NoFly: Walking the Talk on Climate Change, here.
• This story is part of the Herald's contribution to Covering Climate Now, an international campaign by more than 170 media organisations to draw attention to the issue of climate change ahead of a United Nations summit on September 23. To read more of our coverage go to nzherald.co.nz/climate