Sea level rises of just centimetres could make some coastal communities intolerable, a Niwa Scientist says.

Niwa scientist Rob Bell sounded the warning while presenting a report withheld by the previous Government, that shows New Zealand does not have a coordinated plan to address the effects of climate change.

Climate change minister James Shaw said the report made "grim reading".

CHRIS MCKEEN/STUFF Catastrophic flooding in Edgecumbe earlier this year.

"I don't want to sugar coat this, there are significant risks to property and infrastructure, the whole point [of the report] is to get ahead of those risks so we can anticipate and avoid those risks, forewarned is for forearmed".

New Zealand has "decades of urgent work" ahead of it mitigating climate change's damage.



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Despite the sobering report, Shaw was hopeful.

SIMON MAUDE/STUFF Climate change minister James Shaw, and scientists Judy Lawrence and Rob Bell presented the "grim" report.

The report gave New Zealand a "head start" adapting to climate change compared to other countries, he said.

The report found there was "limited evidence" that New Zealand had been proactively adapting to the threat of climate change, and many sectors had been trying to adapt on their own within a mismatched framework of policies and legislation.



New Zealand had a lot of information about how the climate was changing, but "unlike many countries," did not have a coordinated plan. The report's authors "found no evidence that climate change risks to New Zealand have been reduced by the actions taken by central government".

Shaw released a stocktake report from the Climate Change Adaptation Technical Advisory Group, which was set up last year to advise the Government on climate vulnerability.

ALDEN WILLIAMS/FAIRFAX NZ Residents in some small West Coast communities are already feeling the effects of sea-level rise.

The group comprises experts from both public and private sectors. He also released long-delayed coastal hazards guidance for councils, a nearly 300 page document which details how local authorities should consider climate change in planning decisions.

It wanted to "shift people from reacting to climate change events" and take a more "anticipatory approach", technical reference group leader, Victoria University climate scientist Judy Lawrence said at the press conference.

New Zealand communities and public/private sectors needed to be able to take "dynamic action" toward climate change risks "over time".

"How do we deal with risk, how do we deal with vulnerabilities?"

Some council's are already "picking up on ideas" adapting, Lawrence said.

Niwa scientist Rob Bell said it could only be a matter of sea rises in centimetres that could "tip-over" coastal communities into taking "adaptive" planning.

"It may become intolerable for them".

"You'll know some of these [areas], parts of South Dunedin, Hawkes Bay and Auckland, they're priority areas".

"A couple of decades down the track" some parts of the country may become "uninsurable" as climate change affects filter through to insurance premiums, Shaw warned.

DELAYED REPORT

The former Government had not released the interim stocktake report when asked by Stuff, and said the final report would be publicly released in March. Stuff asked the new Government to release the interim report shortly after it was sworn in.

James Shaw said the report had been ready since May, 2017.

"You'll have to ask the previous minister" why the report wasn't released earlier, Shaw told the press conference.

National's climate change spokesman Todd Muller said the May report was an "interim draft".

The Stockdale Report's terms of reference meant it "was always going to be released at this time".

"What I'm more concerned about is seeing the final report and recommendations due for release in March, 2018."

"National is open to working with the Government to build on the plan we put in place to tackle and adapt to climate change," Muller said.

The report shows New Zealand has significant information about climate change, but not all of it was in a form that was accessible or was used to aid decision making.

The Government had been reactive, not proactive, in adapting to climate change, and agencies had mismatched priorities.

"The lack of a nationwide assessment of the climate-related risks means that it is difficult for New Zealand to develop a planned approach for climate change adaptation because priorities for action cannot yet be articulated," it said.

There was an "absence of coordinated leadership on climate change adaptation" and adaptation was not "currently integrated into many central government agency objectives". There were "few examples of anticipatory action on climate change".

A final report by the group is expected in March, and would contain recommendations for how New Zealand can adapt to climate change.

THE EFFECTS

Climate change will increase the frequency and intensity of extreme events such as flooding, drought and wildfires, which poses a threat to many communities, the stocktake said.

The impacts are likely to accelerate over time, and extend broadly across all sectors of society, including the economy, public health and biodiversity.

The stocktake said, for example, "there is a clear possibility that climate change will be a significant driver of biodiversity loss throughout this century and beyond".

Other risks include new, more serious diseases: "A warmer and wetter New Zealand means that we will experience diseases not currently present in New Zealand and potentially more frequent pandemics," it said

Under the mid-range sea-level rise projection, within 50 years, a one-in-100 year inundation event would on average happen every year in Wellington, every second year in Dunedin, and every fourth year in Auckland.

There were likely to be significant impacts on the economy, including both tourism and agriculture. The drought in 2012-2013, for example, cost the country $1.5b, and was an event partly influenced by climate change.

It also posed a threat to low-lying infrastructure and communities. Most of New Zealand's population is either coastal or on a floodplain.

A "risk census" of infrastructure by Niwa in 2015 found billions of dollars of infrastructure was in low lying areas that would be prone to flooding.

They include nearly 70,000 buildings, 2000km of road, and five airports.

The area carrying the most risk is Christchurch, followed by Hawke's Bay.

'SIGNIFICANT WORK REQUIRED'

The stocktake looked at work underway to adapt to climate change, and found there was "significant work required" in some areas.

It said central Government had played a key role in funding research, but there was a lack of coordination and agreed priorities between agencies.

Its actions had "generally been reactive" after a climate-related event had already happened.

The former Government defended not releasing the guidance, saying councils had been aware of its contents during the drafting process.

The absence of formal advice, however, resulted in the Thames-Coromandel District Council approving a flood-prone subdivision while factoring in 1m of sea-level rise, not 2m, Newsroom reported this week.

Climate change has increased the frequency and severity of extreme weather events, scientists say.

A report released this week concluded the extreme rainfall in Houston this year had been 15 per cent more intense and three times more likely to happen due to climate change.

New Zealand is already feeling the effects of a warming climate, the Ministry for the Environment reported in October. Some effects are likely to be irreversible.