Climate change: How hard will extreme weather hit NZ?

Scientists have calculated that climate change increased by 20 per cent the chances of the 2012...
Scientists have calculated that climate change increased by 20 per cent the chances of the 2012-13 drought (pictured) occurring. Photo: NZ Herald
Scientists are taking a deeper look at how hard New Zealand will be hit by one of climate change's most frightening calling cards: extreme weather.

"Extremes do a lot of damage, often come as a surprise and, in New Zealand at least, we have not paid them as much attention as we should," said Professor Dave Frame, head of Victoria University's Climate Change Research Institute.

"Extremes are where New Zealanders are already beginning to feel climate change affect their day to day lives."

In some parts of the country, it's been manifesting with drier soils, fewer frost days and shifted rain patterns.

Scientists have told us there was now even a 50 per cent greater chance of exceptionally high-pressure systems occurring here in summer than was the case a century ago.

"Some locations in New Zealand are now experiencing damage and disruption almost every year that many of us would have previously only experienced once or twice in a lifetime," Victoria climate risk researcher Belinda Storey said.

Climate change has been implicated in, among other drivers, our hottest summer (2018) and our hottest year (2016).

Yet few extreme weather events here have been studied for their direct link: one of them was a five-day deluge in July 2014 that put swathes of Northland dairy country underwater and caused about $18m in damage.

Another was a horror drought that left much of the country brown over the summer of 2012 and 2013; modelling showed that $1.3b had been about 20 per cent more likely to occur today than in the late 1800s.

Even under the most optimistic scenarios, extreme weather events would grow more frequent and more severe over coming decades.

Just half a metre of sea-level rise could threaten some $12.5b worth of buildings, while brutal, long-lasting heatwaves like that which the country sweated through this year could be the norm by end of the century.

Frame is now leading a just-funded, $10m programme bringing together Storey and a team of other top researchers to better understand the full extent of damage expected to be caused by extreme weather events.

They'll investigate how the most damaging weather events are changing in the next 10 to 40 years, and what proportion of individual events, like the Northland storm, can be directly attributed.

In collaboration with MetService, they aim to boost near-term disaster forecasting - directly helping emergency responders - while also compiling a comprehensive historical disaster database with iwi.

"We'll be looking at how climate change is affecting today's extremes, as well as how extremes are likely to evolve in the future," Frame said.

"Both aspects are important for how key climate risks are evolving. The aim is to improve our ability to understand how risks are changing, and so to provide a better basis for preparing for them."

Researchers in the team have already been studying how climate change signals emerge from background variability, and on the links between climate change and observed extreme events.

"This branch of climate science is usually called "attribution" and has had growing prominence in recent years," Frame said.

"We're integrating this branch of science with one that is closely related, and even newer, which is sometimes called 'climate change emergence'.

"And we're tying both to a range of other sciences that are crucial to how these extreme events affect the social and natural systems we care about. We'll be building a comprehensive disaster database for New Zealand, and undertaking economic analysis of losses."

"We're excited to have Vision Mātauranga research and consultation woven through the project too, ensuring our climate modelling delivers what is most important to our iwi partners.

"Whakahura is our Te Reo Māori title meaning to uncover or discover."

Frame said the collaboration, supported through the Government's Endeavour Fund, would be closely aligned to another major, million-dollar project reaching toward rapidly revealing climate change's hand in extreme weather.

That programme, led by Alexandra-based company Bodeker Scientific, aimed to turn out the data in near-real time, with a focus first on weather events marked by extreme temperature or rainfall.


Climate doomsters have been wrong since 1975, at least. How much longer must we accept failed forecasts, and dance to their Dionysian tune. Just go away.

Interesting all these climate change so call experts why do we have to put up with all this scare mongering when in my 80 years every year the climate has changed and it is nothing to do with man made The next 80 years will be the same and no one on this earth will change it

I was hoping the climate was changing and will warm up.... well its very cold today.... so where does that leave us/

The IPCC 5th assessment report states with respect to each type of extreme weather, that there has been no increase and none is expected. The actual weather data collated from around the world for each type of extreme weather again shows no increase. What we have here is media hype which turns every slightly above average weather event into an unprecedented one. The climate models are simply not good enough to forecast anything. This article should be a must read for newspaper editors.

Media editors have peddled doom and gloom at an increasing rate for neigh on 30 years. Virtually none of the claims made this week in covering climate now have any support in the scientific literature. All doom comes from models (read above link) Data from observation gives no cause for alarm, but editors refuse to look at actual data. Where is the 4th estate ?

Anyone who tells you they can forecast future climate is a charlatan. The climate models cannot model clouds. Even the IPCC said they do not know either the SIGN or the MAGINTUDE of the low cloud response to warming. The models factor in clouds as a positive feeback, (will enhance warming). if this were so then the last El Nino shoud have been hotter, it warmed the world by 0.7°C and has now cooled by about 0.5°C , no enhancement from increased water vapour as the models predict. So if they cannot model clouds correctly then any output or claim about the future is pure junk science.
The models all run at a rate of warming 2 to 3 times the observed rate. The satellite temperature from UAH is the only reliable global temperature measurement we have. In the last 40 years it has shown a steady 0.095°C increase /decade.
In the last 5 years, temperatures have been warmer due to the El Nino that peaked in Dec. 2016. El Nino has nothing to do with CO2, it arises from solar heat absorbed directly by the ocean. Climate is averages weather over 30 years a decent La Nina would soon change the present picture. A grand solar minima appears to be starting - history tells us time to buy a coat

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