Climate Change

Report: NZ due for wildfires, storms, droughts

The first ever National Climate Change Risk Assessment has found 'New Zealand’s climate is warming, sea levels are rising, and extreme weather events are becoming more frequent and severe', Marc Daalder reports

Over the next 70 years, wildfires and extreme storms will become more common in New Zealand, vast swathes of coastal property could be inundated by rising sea levels and social cohesion and the financial system could fracture under the pressure of climate change.

Those are the conclusions of a new report, the first ever National Climate Change Risk Assessment (NCCRA), which lays out the ways New Zealand is threatened by climate change and tasks the Government to come up with a response plan to adapt to the impacts of climate change within two years.

The NCCRA was initiated by the passage of the Zero Carbon Act last year and a new one will be published every six years. Future reports will also seek to hold the Government accountable for whether its National Adaptation Plan is strong enough and whether it has done enough to implement the plan.

The first NCCRA found there are 43 specific priority risks threatening New Zealand across five areas: the human domain, the natural environment, the economy, the built environment and governance.

The report highlights the importance of mitigating the effects of climate change through reducing emissions and investing in adaptation to the impacts of climate change, Climate Change Minister James Shaw said.

"Communities across New Zealand are already experiencing the effects of a changing climate, however that does not mean our goal of preserving a safe climate for the future is not within reach. Because it is. That’s why this Government has spent the last three years putting in place some of the world’s most ambitious climate change policies," Shaw said.

"Cutting our emissions is obviously a huge part of what we need to do to create clean, safe and healthy communities for ourselves, our loved ones and future generations. However, the climate is already changing and there will be some effects that we cannot avoid. So, in addition to driving the transition to a zero carbon New Zealand, this Government is also working to ensure our communities are made much more resilient to the unavoidable effects of global climate change."

A warming world

The new report was based on calculations from NIWA which found the world could be 2 degrees warmer than pre-industrial times by 2040 and 4 degrees warmer by 2090, if global emissions remain high. The goal of the Paris Agreement is to limit temperature rise to "well below" 2 degrees and strive to halt warming at 1.5 degrees above pre-industrial levels.

The Zero Carbon Act similarly requires the New Zealand Government to reduce emissions in a manner consistent with limiting warming to 1.5 degrees.

The world's oceans are already 14.6 centimetres higher today than they were in 1960. That trend is only expected to worsen, NIWA found, with sea levels projected to rise by another 21 centimetres over the next two decades and a further half-metre on top of that by 2090.

In 2040, there will be 50 percent fewer cold nights - where temperatures fall below 0 degrees - in New Zealand than there are today. By 2090, the number of cold nights will have nearly halved.

On the other hand, the number of days where temperatures peak above 25 degrees will double in the next 20 years and quadruple by 2090. There will be a 5 percent increase in the number of dry days across the country by the end of the century and one-in-10-year extreme rainfall events will become a third more likely to occur.

Droughts will become more common and there will be, by 2090, 30 fewer snow days a year than the current average. The South Island will become less humid and gale winds will become as much as 10 percent faster in the lower North Island and across the South Island.

This scenario is based on a United Nations-devised trajectory for potential emissions increases and temperature rise over the remainder of the century. Called RCP 8.5, the scenario is essentially the worst-plausible-case business-as-usual outcome if emissions continue to rise.

As it stands, global emissions are still rising. They reached a record high in 2019 and are only set to decline between 4 and 7 percent in 2020 due to the Covid-19 lockdowns that were implemented in most countries, including some of the world's biggest polluters. Climate scientists have said that global emissions must halve by the end of the decade, or fall 7.3 percent every single year from 2021 through 2030, if we want to limit warming to 1.5 degrees.

That seems unlikely - even New Zealand, which talks a big game on climate change, still expects emissions to rise through 2025 at the earliest. After that, as Newsroom has reported, emissions are expected to decline slowly - by 2030, they will still be higher than in 2018.

Urgent risks to society, economy and environment

Of the 43 priority risks identified in the NCCRA, 10 were deemed urgent by the report's authors.

For the natural environment, the urgent risks were to coastal ecosystems from sea-level rise and more frequent extreme weather events and to native species and ecosystems from invasive species.

"Sea-level rise, coupled with more frequent, extreme storms, will pose risks to a broad range of coastal ecosystems and threaten many species, including many found only in coastal environments. This includes highly productive coastal ecosystems with important breeding, roosting and foraging habitat for indigenous bird species," the report found.

"Expanding and new pest species are likely to compromise our ability to maintain the integrity and functioning of our indigenous ecosystems, and to increase the challenge of protecting our at-risk and threatened species."

The key risks to human society were the breakdown of social cohesion and community wellbeing and the exacerbation of existing inequities. The report notes that coastal communities may have to be relocated or fragmented and points to Kelso, an Otago town of 200 residents that had to be relocated throughout the region after severe floods in 1978 and 1980, as an example of what could be expected.

"The townspeople have held reunions but the social bonds within the community were ultimately broken," the report notes. The consequences for tangata whenua could be equally dire.

"It is likely that cultural, economic and social capital as well as spiritual wellbeing will be adversely affected if Māori are forced to relocate from tribal lands and territories."

The impacts of climate change and related natural disasters could also be felt more keenly by people who are socioeconomically disadvantaged or otherwise marginalised, the report states.

The economy will also be put under immense pressure, with the economic costs of lost productivity and disaster relief identified as an extreme risk and the stability of the financial system at major risk.

Global GDP could decline by 5 percent a year if climate change is allowed to run rampant, the report warned, which would put a significant dent in the ability of Government to fund a response to climate change.

Moreover, "Climate change presents a systemic risk to the financial system, with severe impacts on the real economy," the report found. The insurance sector will be unable to affordably insure large swathes of coastal property, banks could see their assets damaged by extreme weather events and overall disruption to supply chains could have a knock-on effect on the global economy.

Buildings and governance at risk

The two urgent risks to the built environment - threats to potable water and the vulnerable of buildings to sea-level rise and extreme weather events - were also graded as extreme.

Recent droughts have led to Auckland's severe water shortage and these are only expected to worsen as the world warms up. Moreover, algal blooms proliferate during droughts, which could contaminate the remaining water supply.

Buildings throughout the country are also jeopardised by the impacts of climate change.

"Many buildings in New Zealand (both residential, non-residential and cultural heritage) are at risk from climate change, mainly from extreme weather events, drought, increased fire weather and rising sea levels. Buildings are also at risk from associated natural hazards like inland and coastal flooding, landslides, groundwater rise and wildfire, all of which are projected to become more frequent and severe," the report notes.

The final urgent risks concerned New Zealand's governance arrangements and ability to appropriately respond to the challenges outlined above.

These included the risk of improper responses and the risk that "climate change impacts across all domains will be exacerbated because current institutional arrangements are not fit for climate change adaptation".

"Using processes and tools that characterise risks as static, and rely on historical parameters that do not account for uncertainty and changing risks, increases the risk of maladaptation," the report found.

There is also difficulty around the legal ability of councils to refuse consents for climate change reasons or fund the infrastructure needed to adapt to the impacts of climate change. This is part of the reason an expert review panel recommended last week that a new law, the Managed Retreat and Climate Change Adaptation Act, be passed to address these and other legal concerns.

The NCCRA also concluded that many areas were at risk from numerous impacts of climate change - buildings, for example, are threatened by sea-level rise-related inundation, extreme storms and wildfires.

Moreover, some impacts can build on one another, making a bad situation worse. The report labelled these scenarios "cascading impacts".

"For example, floods can badly damage roads, and compromise electricity grids and potable water supply. Damage could disrupt tourism and supply chains, with flow-on to other value domains," the report stated.

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