Jessica Bowan wades through floodwaters in Temuka, Canterbury, last May. That storm was calculated as being 10 to 15 per cent more intense as a result of climate change. Photo / Supplied
A major UN report has warned of "cascading and compounding" climate impacts ahead - and one of its Kiwi authors says New Zealand's adaptation efforts are moving too slowly.
The latest report by the Intergovernmental Panel on Climate Change (IPCC), released overnight, painted another stark picture for the planet – warning that some severe impacts could become irreversible if warming even temporarily passed the 1.5C mark.
But even if we could keep temperature rise within that symbolic threshold, by the time young children today turned 80, they would've experienced a nearly four-fold increase in extreme events like heatwaves, droughts and floods.
By 2100, the proportion of the world's population exposed to deadly heat stress was also projected to climb from 30 per cent today to somewhere between 48 and 76 per cent.
As many as three billion people could experience chronic water scarcity from droughts if warming reached 2C – and up to four billion under 4C of global temperature rise – with grim consequences for food production and ecosystems.
New Zealand could expect much more of what climate change has already brought us: more hot days, fewer cold days, melting glaciers, rising snowlines, heavier deluges and gradually acidifying oceans.
Northern regions would suffer more droughts and extreme fire danger, it found, while, on our southeastern coasts, effects like ocean warming and marine heatwaves could kill off kelp forests.
"This report is a dire warning about the consequences of inaction," IPCC chair Hoesung Lee said.
"It shows that climate change is a grave and mounting threat to our wellbeing and a healthy planet."
Along with driving down emissions as hard and fast as possible, nations needed to put equity and nature at the core of adaptation efforts – especially as the world became more urbanised.
By 2050, two thirds of the global population would be living in cities, which report co-author and Canterbury University political scientist Professor Bronwyn Hayward described as a "crucible" for "cascading, compounding" risk.
Adaptation progress was slowest among lower-income populations, but particularly in urban areas with poorly-planned growth and a lack of basic services.
"But also, because we've put so much emphasis on engineering solutions like sea walls, we've lost sight of the importance of social and ecological infrastructure."
Restoring degraded ecosystems and effectively conserving 30 to 50 per cent of remaining natural habitats, for instance, would boost nature's ability to absorb and store more carbon, while also putting the world on a path to sustainable development.
"As well as good urban design, it's also about considering underlying insurance systems, social income support, our health and education, and where we are locating people.
"The report is very frank about the fact those most affected are going to be the poorest and most vulnerable, including the elderly, children and disabled communities.
"Indigenous communities are also at risk."
One of the 250 experts behind the report, Hayward, said it was "remarkable" that, in signing off on it, nearly 200 nations had acknowledged human rights and justice lay at the centre of the climate crisis.
Whereas the first part of the UN's sprawling Sixth Assessment Report gave a startling stocktake of the latest science – that critical 1.5C mark could be crossed in a little over a decade – she felt this second instalment, released seven months later, helped to chart a way forward.
Fellow author Dr Judy Lawrence, of Victoria University, saw New Zealand as no different in needing to "step up" action through better governance arrangements, and investing in smarter adaptation.
A 2020 Government risk assessment found 675,500 Kiwis lived in areas already prone to flooding, with a further 72,065 living in the firing line of where some of the most dramatic effects of sea level rise could hit.
Buildings, too, were at extreme risk – nearly 50,000 of them were currently exposed to coastal flooding, and at the highest range of warming scenarios, that could rise to nearly 120,000 this century.
Yet the Government was still to release its long-awaited national adaptation plan, while work on its new Climate Change Adaptation Act has been delayed by Covid-19.
All the while, councils have been calling on Wellington to help address the critical issue of who paid for what.
"The progress we are making is very slow," Lawrence said.
"We do have tools that can help us, but we don't have legislation and governance lined up between central and local government.
"While we have cases where there are collaborations, like on the east coast of North Island, we still haven't implemented solutions."
Having more people exposed and vulnerable to climate impacts would create a "huge cost" for future generations, she said.
"We have to integrate the long-term – where we're heading, what the trajectory is – into the decisions we're making today, because otherwise, we'll just lock in more people who'll be affected."
Climate Change Minister James Shaw agreed a "huge step change" in our approach to climate adaptation was needed, adding he was particularly concerned over potentially disproportionate impacts on Māori.
"But we mustn't lose sight of the urgent need to lower our emissions," he said.
"The next 10 years is make or break for the planet, and the severity with which we will experience climate change can be lessened if we do all we can to limit warming.
"Very soon we will release New Zealand's first, Emissions Reduction Plan, which will outline the changes we need to make across every sector to lower emissions and limit catastrophic warming."