As world leaders prepare to head to Glasgow for crucial UN climate talks, Herald science reporter Jamie Morton talks to those who will feel it most if the summit fails.
Brianna Fruean has a better reason than most of us to care about climate change: she doesn't want to lose her home.
Growing up in Samoa taught her much about the precarious state of the planet's climate - and the implications for millions of people on islands dotted across the Pacific.
"My parents had a business close to the Vaisigano River, which flows through Apia, and almost every rainy season, the river would flood - no one had ever seen that before," she said.
"We might think of climate change as weather patterns - like floods, cyclones, or droughts - but when you see it in front of your eyes, it's the kids who are having to move homes and stay at their Auntie's house.
"Or it's the families who are having to pull their kids out of school because they depended on fish to pay the school fees, and because the ocean is warming, they're not getting the same fish stocks they used to 10 years ago."
The 23-year-old Pacific Climate Warrior, now studying at the University of Auckland, said her island upbringing had "completely built" her passion for climate activism.
A founding member of the Samoan chapter of the climate organisation 350.org, she's lobbied for the Pacific around the world.
"I really feel like the Pacific is the canary in the coal mine: even though we're among the first places experiencing the harsh consequences of the climate crisis, we're not going to be the last."
The gathering storm
Last December, one of the most ferocious tropical cyclones ever observed, and packing top wind speeds of 260km/h, tore through northern Fiji.
Fiji's prime minister, Frank Bainimarama, called the category-5 Yasa "a climate emergency".
More than 23,000 Fijians were forced into evacuation centres and some 4,200 homes were destroyed or damaged - one of them collapsing upon and killing a man and a three-month-old baby.
Yasa, which ultimately wrought more than $340m in damage, indeed bore some of the traits that scientists expect to see more of in tropical cyclones.
It was particularly strong for a system so early in the season, it intensified quickly but moved slowly, and blasted the islands with extremely high winds and rainfall.
While the total number of cyclones in the Pacific is predicted to decrease under climate change, their severity will worsen.
That's because the tropical cyclones of the future will form in a climate warmer, wetter and more energetic than before - resulting in destructive systems that develop and intensify faster, and carry more water and extreme wind.
But for New Zealand's island neighbours, it's only part of the problem in a planet even 1.5C warmer than pre-industrial times - a threshold that could well be reached as early as the 2030s.
While there's still a lack of precise, quantitative studies of projected impacts for sea-level rise at the 1.5C and 2C marks - and some recent research suggests many islands may be more naturally resilient than first thought - it's clear higher oceans will also bring threats like erosion, flooding and salinisation of water supplies.
On top of that, other effects like ocean warming, severe cyclones and mass coral bleaching risk knock-on impacts for everything from human health to agriculture and resources.
The UN's major 2018 climate report, found that in low-lying atolls, 40cm of sea-level rise - which could come with 1.5C of temperature rise - may endanger freshwater resources.
By last year, global temperatures were already 1.2C above pre-industrial levels - while oceans have risen an estimated 20cm since 1850.
As this year's sweeping UN Sixth Assessment report brought more dismal predictions for the Pacific - with a 2C world spelling drying in some parts of the region, and heavier rainfall in others - Pacific leaders pleaded again for international help.
It wasn't too long ago that Fruean wouldn't discuss climate-driven migration.
"I thought that, if we start speaking about migration, it's like we're giving up."
More recently, though, as the planet continues to heat, she says island states have begun to talk more about such inevitabilities, as well as adaptation and mitigation.
"We should at least have some conversation, so we're prepared if worse comes to worst."
In a brief last year, Otago University researchers noted that, in 2019 alone, nearly 24 million people from some 140 nations were displaced due to climatic disasters - and that the Pacific was among the most affected areas.
According to assessments by the Internal Displacement Monitoring Centre, at least 50,000 Pasifika people were at risk of losing their homes each year due to climate-related pressure.
Especially vulnerable were low-lying, small island nations like Fiji, Kiribati, the Marshall Islands, Solomon Islands, Tonga, Tuvalu, and Vanuatu.
A 2018 Cabinet paper noted that as many as 180,000 people living in Kiribati, Tuvalu and the Marshall Islands, alongside residents of Tokelau and atolls of some larger island states, would be "significantly affected" by the crisis.
And within the last decade alone, it's been estimated that one in 10 people in Kiribati, Nauru, and Tuvalu had already been displaced.
On a broader scale, Fiji, Papua New Guinea and the Solomon Islands - collectively representing 85 per cent of the total Pacific population - were already struggling with displacement.
While some people were being forced to shift to other countries, most movement still occurred within countries' borders - even when resettlement areas were similarly exposed.
"Generally, people don't want to leave their home, where they grew up over generations," said Dr Dennis Wesselbaum, an Otago University macroeconomist who studies climate migration.
In time, however, he expected domestic displacement would ultimately be followed by more cross-border migration.
"Then, rich and developed nations like New Zealand and Australia seem to be obvious candidates for migrants."
He added that the direct impacts of global warming, like weather extremes, wouldn't be the only drivers.
Climate change could spell income loss, especially in agriculture sectors; health risks from threats like vector-borne diseases; weakened or failed states; and regional conflict over food, energy or water security.
"I think that the impacts of climate on daily life and wellbeing become larger over time," Wesselbaum said.
"The direct and indirect channels seem to be adding up and the total impact becomes stronger."
A recent New Zealand Defence Force report predicted that climate-driven security impacts would be a "critical component" of operation planning over years to come, alongside our traditional humanitarian role in the Pacific.
Amid these spiralling dangers, New Zealand has been singled out in successive global studies as something of a lifeboat or safe haven - one recent paper in the journal Sustainability noting our location, political stability, agriculture and renewable energy.
Victoria University climate scientist Professor James Renwick recalled Cold War times when that distinction was often made in the context of nuclear war.
"And I think that's the same idea now. I personally don't think any country is going to be particularly well off under climate change, but there's a view that we're nominally clean, green and temperate, and will continue to be like that for a while."
The Pacific's lifeboat?
Climate Change Minister James Shaw told the Herald he expected climate-forced migration to New Zealand and Australia to be not a surge, but a gradual, staged process over a long period of time.
"There won't be a day when 180,000 people suddenly need to find a new place to live."
Still, he acknowledged New Zealand currently wasn't prepared for a major influx of climate refugees - a problem not unique to our country alone.
International law itself was woefully equipped to grapple with the crisis; the 1951 Geneva Convention provided grounds for refugee status, but not climate-induced migration.
That meant displacement fell into global policy gaps, which has led scholars to call for dedicated new frameworks to protect people forced from their homelands.
One such document - the UN's 2018 Global Compact for Migration - covered all dimensions of the refugee issue, yet remained non-binding.
New Zealand voted in favour of it, quite aware that it didn't create any new legal obligations or affect our sovereignty.
The country's best-known attempt at its own policy - an "experimental humanitarian visa" from displaced Pacific countries, introduced in 2017 - was eventually abandoned.
So far, there have only been a handful of instances where people have tried to claim such status here - the world-first case of Kiribati national Ioane Teitiota's ultimately unsuccessful bid being the most famous.
Within the regulatory void, environmental lawyer Teall Crossan, author of the book The Climate Dispossessed, Justice for the Pacific in Aotearoa, said "fundamental" legal issues lingered.
"If Pacific peoples seek refuge here, how would we honour the rights of a country destroyed by the climate, and not cause further injustice in light of Te Tiriti o Waitangi and our failure to honour Māori sovereignty in Aotearoa?"
There were, at least, some existing avenues available for people at risk of displacement.
The Pacific Access Category, for instance, accepted around 250 people from Fiji, 75 from Kiribati, 250 from Tonga and 75 from Tuvalu each year.
In the background, the Government was developing an action plan to build a better evidence base around the impacts of climate-induced migration.
Asked if there was any interest in reviving a climate refugee visa, Shaw told the Herald that this would be addressed by "subsequent decisions" of New Zealand's overall strategy.
"But the partner governments that we've been working with have been very clear with us - they're very focused on ensuring that people don't need to move, because people want to stay in their homelands," he said.
"So, whilst we do need to take preparatory work for a scenario where there is forced migration, we need to do that within New Zealand. The work that we do with the islands is all about ensuring people don't need to move at all."
Shaw cited one such example, where Fiji had recently asked New Zealand for assistance in translocating 43 villages away from the coastline, to higher ground.
Are we really doing enough?
Last week, the Government committed another $1.3 billion to support countries most vulnerable to climate impacts, of which around half would go to the Pacific.
Shaw said investing in climate adaptation now could spare communities having to deal with worse crises in the future.
"The problem with the nature of climate change is that, by the time you feel the effects, you're roughly 20 years too late to have done anything about them."
The four-fold funding increase meant New Zealand's contribution to global climate funding matched on a per-person basis that of the UK, which is about to host the next major UN climate summit in Glasgow.
"I have seen and heard first-hand the impact of climate change in our region," Prime Minister Jacinda Ardern said.
"We need to continue to step up our support for our Pacific family and neighbours who are on the front line of climate change and need our support most.
"The investment will enable New Zealand to support clean energy projects in developing countries, ensure buildings are able to withstand more damaging storms, crops are resilient to droughts, floods and new pests, and communities are protected from sea-level rise and storm surges."
Crossen said the funding boost was a positive development, "but it is not matched by a meaningful plan to reduce our domestic emissions".
"New Zealand has a shameful history of inaction on climate change. While the current government has made some efforts to turn this around, we are not doing nearly enough."
While New Zealand has locked in its Paris Agreement pledges and its Zero Carbon Act, among other commitments, its 15-year Emissions Reduction Plan won't be released until mid next year.
The greenhouse gases that New Zealand produces account for less than 0.2 per cent of the global total, but, partly because of our unusual agricultural emissions profile, our per capita emissions rank as the sixth-highest in the OECD.
Put together, the Pacific itself is estimated to contribute just 0.03 per cent of global emissions.
"I've heard any number of Pacific Island leaders say the best thing people in New Zealand and elsewhere can do for us to reduce your emissions, before it becomes too overwhelming for us," Renwick said.
"Developed nations, especially the US and China, are the ones most responsible for change, yet the ones with almost nothing to do with it almost, are copping it faster."
As far as she was concerned, Crossen said no amount of climate finance in the Pacific could realistically protect island countries from climate damage without emission cuts.
"Our lack of action at home also acts as a handbrake to unified Pacific calls for global ambition at the international climate talks."
Fruean put it her own way.
"This is about more than just aid. It's about knowing that developed countries like New Zealand are actually willing to lower their emissions," she said.
"You can't have someone just destroy your home, and then pay you money to fix it."
This story is part of a Covering Climate Now reporting series on climate migration called "Flight for Their Lives." CCNow is a global journalism collaboration strengthening coverage of the climate story.