Friday, May 5, 2023

Don't mention Hunga Tonga

For months the country has felt as if it’s under a state of siege – not from a hostile foreign power, but from extreme weather. 

This week, the north of the country has been pummelled again by torrential rain, gale-force winds and high seas. RNZ reported this morning that more heavy rain warnings had been issued for the west coast of the North Island and the top of the South. 

But please, whatever you do, don’t mention Hunga Tonga.

Constant weather warnings have created a pervasive sense of anxiety. Night after night, the TV weather maps show heavy rain. I’m surprised that the graphics people even bother to redo them.

We’ve become familiar with scary colour codes denoting storms of varying severity. Meteorologists whom no one had previously heard of have been thrust into national prominence in the same way that epidemiologists became household names - celebrities, almost - during the Covid crisis. 

But the experts don’t say anything about Hunga Tonga, and quite rightly. We wouldn't want people to get the wrong idea.

In some areas, Taranaki being the latest, residents have been advised to have emergency grab bags prepared in case they have to be evacuated suddenly. In Nelson last night, the city council opened emergency accommodation as a precaution.

In Hawke’s Bay, Tairawhiti, Coromandel and West Auckland, traumatised farmers, orchardists, grape growers and home owners are still cleaning up after Cyclone Hale, Cyclone Gabrielle and the Auckland Anniversary Weekend floods. In parts of Hawke’s Bay, people are still digging themselves out from under several metres of silt.  But please don’t make the mistake of thinking this has anything to do with Hunga Tonga.

Vital highways remain closed by storm damage. SH2 between Napier and Wairoa, closed for three months, is scheduled to reopen on May 14 once a Bailey bridge has been completed on the devastated Waikare Gorge section. Repairs to SH25A on the Coromandel Peninsula may take until next year. But it would be pure mischief to implicate Hunga Tonga.

The Wairarapa, where I live, has largely escaped the worst of the mayhem, although floodwaters inundated the Tinui School, on the road to Castlepoint, and forced its closure. But even here, we’re lamenting a summer that never was. One rural contractor, in business since 1988, said it was the wettest season he’d experienced. Crops went unharvested because the rain was almost constant.

Masterton got through summer without water restrictions, which is almost unheard of. Lawns that would normally be mown every few weeks, and then only to keep the weeds down, just kept growing. The glorious hot, dry spells that we’ve come to expect since moving here 20 years ago just didn’t happen.

The statistics tell the story. In January, 182mm of rain fell at Masterton Airport compared with the historical average of 83mm. In February we got 159mm compared with the average of 25mm.

And when it wasn’t raining, it was threatening to rain. It was a summer of gloom. NIWA figures show that Masterton had 536 hours of bright sunshine during summer compared with the average of 649. That may not sound like a huge difference, but ask any family camping on the coast how much fun they had this summer. Not bloody much, they’ll tell you. But Hunga Tonga? Nah.

By now you’re probably muttering, “Hunga what?” and wondering what the hell I’m on about.

Hunga Tonga-Hunga Ha’apai is the underwater volcano that erupted near Tonga in January last year. I wrote about it here.

To recap a couple of key points from that blog post, Hunga Tonga was the most powerful eruption so far this century. According to NIWA, it was the biggest atmospheric explosion recorded in more than 100 years, measuring nearly 6 on the volcanic explosivity index – roughly equivalent to that of Krakatoa. The eruption created a volcanic plume that reached 58km into the mesosphere.

An article in the scientific journal Communications Earth and Environment – one of many devoted to the event – noted that major volcanic eruptions are well-known drivers of climate change and said the magnitude of the Hunga Tonga explosion ranked it among the most remarkable climatic events in the modern observation era. Researchers calculated that it resulted in a 13% increase in global stratospheric water mass and a fivefold increase in stratospheric aerosol load – the highest in three decades.

One study estimated the amount of water displaced as 58,000 Olympic-sized swimming pools, or about 10 percent of the entire water content of the stratosphere. That’s a helluva lot of water and it has to go somewhere. Communications Earth and Environment said the eruption had “potential long-lasting repercussions for stratospheric composition and climate”.

Similarly, Atmosphere magazine devoted a special issue to the eruption, calling it an epic event that would have a continuing effect on the climate, both locally [that probably includes us] and globally.

It seems reasonable to conclude that an eruption of that scale might at the very least be a factor in the freakish weather patterns of the past few months. Yet I can’t help suspecting that the eruption of Hunga Tonga is the climate event none of the New Zealand experts want to talk about, possibly because it cuts across the official narrative that the extreme weather of the past few months is all due to climate change.

In a New Zealand Herald article published two months ago, New Zealand meteorologists seemed to go out of their way to play down the Hunga Tonga factor. While acknowledging that eruptions can have climatic impacts, they attributed our wayward summer weather (and now autumn as well) to other causes. James Renwick said much of the excess moisture from Hunga Tonga would have been rained out within weeks. He and Jim Salinger posited that La Niña and something called the Southern Annular Mode were far more important. The other big factor, of course, was background climate change. Nothing new to see here, folks.

Obviously I can’t contradict them. They’re experts and I’m not. But can we rely on the likes of Renwick and Salinger being rigorously objective? I’d like to say yes, but both have nailed their colours to the climate change mast and the subject is so politicised that we can be excused for having doubts. Science is not immune to ideological contamination, as we learned from the shameful gang-up that followed the Listener letter about matauranga Maori.

Setting aside all the arguments about whether climate change is human-induced, and to what extent (if at all) we can mitigate it by riding bikes, buying Teslas, planting trees and punishing farmers, I think most people can accept that the climate is changing. Even my own amateur observations suggest it’s happening. One admittedly crude measurement is the frequency with which the Remutaka Hill road is closed by slips. When we moved from Wellington in 2003, such events were infrequent. Now they happen regularly. That can only be the result of the ground being saturated and destabilised by constant heavy rain. The frosts, too, are fewer and less severe.

But what’s happened lately feels different. 
Gabrielle was New Zealand’s worst weather event this century. The Treasury puts the likely combined cost of the cyclone and the Anniversary Weekend storm at $9-$14 billion.

Climate change is surely a gradually evolving trend, and that doesn’t gel with what New Zealand has experienced this year. The recent extreme weather events have been freakishly violent and abrupt. They feel like outliers – striking departures from the norm – rather than the predictable continuation of a long-term pattern. If I'm wrong, such events are the new normal and we face an unimaginably dismal future.

Just by suggesting this, I probably risk being labelled as a conspiracy theorist from the alt-Right and put on the watch list of the Disinformation Project (which, incidentally, has so far failed to respond to my requests for information about who funds it – a novel approach for activists who like to promote themselves as champions of transparency). But where climate change is concerned, as in all issues where ideology intrudes, I’m inclined to follow the advice of my late colleague Frank Haden: doubt everything with gusto.

23 comments:

Steve said...

Karl, we can do some back of the envelope figures here to check this out. Your article says the amount of water thrown into the stratosphere by the eruption was "58000 Olympic size swimming pools", which a quick google search shows comes from a study by NASA's JPL laboratory. This source is universally held in reverence and awe by the Internet even though they seem to have trouble using SI units.

Another google search tells me that an Olympic size swimming pool holds 2.5 million litres so 58000 of them would be 145,000,000,000 litres.

The next conversion is to remember that one litre of water would cover one square metre to a depth of one millimetre. So if those 145,000,000,000 litres of water rained out evenly, they would dump one millimetre of rain on an area of 145,000,000,000 square metres. Which seems like a huge number but we can do another conversion because we know (well, Google knows) that 1 square kilometres is 1,000,000 square metres. So now we have 1mm of rainfall over 145,000 square kilometres.

That still seems large but yet another Google search tells us that the total area of the North Island (of New Zealand) is 113,279 square kilometres. We would need about 1.3mm of rain to fall evenly across the entire North Island to have the entire volume of water erupted into the stratosphere by the Hunga Tonga eruption returned to the surface. Wikipedia defines a "light rain" as less than 2.5mm per hour so effectively, half an hour of light rain over the whole of the North Island would have been enough to cancel out the Hunga Tonga eruption.

Of course, it isn't a simple as that; I may have made a calculation error somewhere or the original "58000 Olympic size swimming pools" figure may have been incorrect (although it does map quite closely to the 1.45Tg figure found elsewhere on the interwebs) or the effect maybe more from the water staying in the air rather than falling to earth or maybe the stratosphere was a red herring and we should be looking at what was thrown into the atmosphere or maybe one of a hundred other things - but it does look like the impact of Hunga Tonga probably wasn't as much as your fear.

Simon Arnold said...

Just a little curiosity more than anything. As a kid I remember the Whareama River routinely flooding Tinui,sometimes even blocking access to Masterton, with the floods reaching at least the original school and the local churches.

The new school, built while I was still there, was on higher ground, but still I remember the playgrounds/paddocks getting standing water on them.

I gather the Church of the Good Shepherd (where the first Anzac service was held) finally got moved to higher ground in 2019. Dad had been the local vicar so we were particularly sensitive to these events.

So maybe not that unusual weather down in Wairarapa.

Gary Peters said...

Steve, it's additional water at a single time. It doesn't just "fall" it circulates and impacts weather within that "stream". At the same more water in accumulating and we get a higher moisture concentration.

The Nasa paper indicated a 2-3 year impact cycle and it seems they have been right.

How much actual water was displaced by the "Boxing Day" 2004 earthquake, 30 cubic kilometers so less than 10% of the entire ocean yet the little displacement managed to kill over 200,000 people.

As they say, sometimes a little goes a long way.

https://www.reuters.com/business/environment/tongas-volcanic-eruption-may-harm-environment-years-scientists-say-2022-01-18/

Andy Espersen said...

Ha - you are so right, Karl. Don't we all know that all bad weather events are caused by increased CO2 emissions!! Our children are taught so at school - we ourselves hear nothing else from the main media - both Labour and National governments have been saying so for years. Luxon has just now confirmed his "faith" (!!!) in the Paris agreement - even hinting otherwise makes you an evil, despicable conspirator.

Sorry, Karl - it is now too late for you!! You are now one such! Please let us know the messages you will now receive from the woke brigade.

Chris Nisbet said...

It seems perfectly reasonable to question whether something as significant as the Tonga eruption might have had some impact on the climate, and over how long a period of time. We certainly had some fairly special sunsets here in Auckland for months after the eruption, so if it could do that, why not affect the weather at least for a little while as well? What is disappointing is that anybody who has the temerity to ask such questions is made to feel that they denying science or maybe a little slow.


The Gabrielle event was weather. The period of time Auckland had a few years back where it didn't rain at all for a few months was also weather. In both cases we were told that they were a consequence of 'climate change'. The implication being that they wouldn't have happened if not for humans burning FF. This is simply nonsense. It doesn't happen so much any more, but we used to get reminded that individual weather events are not proof of 'climate change', and it's the change of frequency/intensity of those events of long periods of time (generally grouped into 30 year blocks) that give us an idea if/how the climate has changed.
Ian Wishart has done some good work by finding that NZ has experienced really bad weather like Gabrielle many times in the past. The IPCC reports tell us that there is little evidence that things like accumulated cyclone energy (ACE) has been affected by us filthy humans - actual measurements tell us that ACE has actually dropped, if anything.
Cyclones happen all the time, and the thing that was different about Gabrielle wasn't that it happened, but that it managed to find NZ.

Here's a link to a fairly new document produced by the government about climate change projections.

https://environment.govt.nz/assets/publications/Climate-Change-Projections-Guidance-FINAL.pdf

Here's a snippet from it about heavy rain (highlights are mine)...

"In AR6, there was low confidence in trends in the frequency of heavy rain days with mostly decreases simulated over New Zealand (Caloiero, 2015; Harrington and Renwick, 2014)"

'low confidence' means they don't really have any idea. Are we meant to think that IPCC are a credible source of 'climate change' info, or not?

Here's another about flooding events...

"There is medium confidence that river flooding will increase in New Zealand. Projections for New Zealand indicate that the 1-in-50 year and 1-in-100 year flood peaks for rivers in many parts of the country may increase by 5 to 10% by 2050 and more by 2100 (with large variation between models and emissions scenarios), with a corresponding decrease in return periods for specific flood levels (Gray et al., 2005; Carey-Smith et al., 2010; McMillan et al., 2010, 2012; Ballinger et al., 2011)."

You would have to twist what they're saying there in a very special way to think that they're saying events like Gabrielle are now the 'new normal', which is what is being suggested by some people. It's really annoying when politicians declare there can be 'no doubt' that Gabrielle was due to 'climate change', when even IPCC aren't that sure.

An earlier report (can't find a link to it right now) predicted rainfall changes in NZ of +- a few percent by the end of the century, and they usually weren't even sure of the direction. I'd be amazed if rainfall didn't change by a few percent by the end of the century, with or without 'climate change'.

For me, the upshot is that 'climate change' isn't settled, and it certainly isn't as simple as 'CO2 dunnit, and we all need to completely change our lifestyles to combat it'.

Apologies if I got a bit ranty.

Malcolm said...

National MP Maureen Pugh asked James Shaw for evidence that the particular event of cyclone Gabrielle was induced by human activity. .She was in effect, asking James Shaw to respond to the evidence, (which is well described in your article), that cyclone Gabrielle could have been caused by, or at least affected by, the Tongan eruption. This is an important question. The answer could have significance for the nature and cost of NZ's response to climate change. It might assist in examining the relative contributions to climate change arising from both human activity and natural events. So instead of rebuking Maureen Pugh, Christopher Luxon should have insisted that James Shaw answer the question. Even now he should be doing so. The opportunity to learn from the proximity of the eruption and the cyclone should not avoided.To ask the question was not a denial of climate change. To rebuke the questioner is as difficult to comprehend as is James Shaw's dismissive response.

Tom Chambers said...

Firstly water vapour that goes into the stratosphere doesn't come down as rain.
Second, here is a prediction by an Australian meteorologist about the Australian summer and how it was going to be a flooded one.
Jim Salinger dismissed the effect of the Tongan volcano as the Northern Hemisphere hadn't seen anymore rain than usual. When you are a climate alarmist, nothing can come between you and your beliefs.

Mark Hubbard said...

Yes. I live on roads that are ruined for two years in Marlborough Sounds. Since the storm last August, the Marlborough District Council went cap in hand to NZTA and we have been stuck in a pointless and endless, plus inhumane, consultancy with Stantec NZ since making our 'business' case for continued public road access to our houses. Every meeting they and MDC warn of 'climate change' and I now realise they are softening us up to tell us, all or some, that we will be expected to go to sea access, our roads won't be repaired.

In all my correspondence I point out Hunga Tonga: no one will let that in the debate, it's just we have to plan for climate change which will be the end of living in one of the best places in New Zealand.

In the process Stantec has done surveys, etc, on our mental health, but not once asked us if we can live in our houses without road access. Most of us can't. My wife and I certainly can't. Most of the 140 house on our Moetapu Bay Road were built for public road access and can't get to the sea without the road.

It's a farce. And I say inhumane because our house values - that's our retirements - are ruined because for two years now and counting we can't guarantee future access by road to any of our thousands of affected houses in the Sounds. We can't sell (some are having to at big discounts). For health reasons we wanted to sell last summer, but I'm not giving our house away; can't afford to. Stantec have another two, that's TWO rounds of consultancy before their bullshit 'business case' even goes to Wellington so that's next year I suspect and another summer.

Not one of the Stantec consultants lives in the Sounds: none of them have skin in the game and they seem totally unconcerned about time (they're milking it as long as they can).

Nothing is being done on our road. In two places it balances precariously over the sea on a single ribbon of road left clinging to the hill and is dangerous. It could easily go this winter and we have to barge out and go live in Christchurch.

Transport Minister Michael Wood does nothing. He's an incompetent brute.

After constant pleas to our sitting MP, Stuart Smith, National, he does nothing, happy, quote, 'with the consultation process' despite it's taking years. He should be representing us and talking compensation for those needing to sell by this stage but will not get off his lazy arse.

Simeon Brown, National Transport: crickets.

Act: crickets.

Not one bugger in Parliament will represent us.

So I'm throwing away my vote this year on DemocracyNZ in sheer fury.

Road users have been screwed over: roads are our goddamned lives. We need a government of infrastructure for a decade, no ideology.

Karl du Fresne said...

Did you mean to include a link, Tom?

Mark Hubbard said...

Regarding Tom Chamber's post: the ad homenim at end should warn you for caution.

As for Jim Salinger and unbiased 'science' save me.

I'll be interested if Tom gives a link because the only Australian meteorologist I remember reading some 18 months or so ago, I don't have the link, was showing the link of Hunga Tongo directly to the weather pattern that caused the Melbourne floods. That was why I started bringing it into correspondence with MDC regarding our Marlborough roads.

So, that link Tom?

Trev1 said...

"If we disallow skepticism and debate, we end with no science". That is guiding principle of Javier Vinos' landmark study, "Climate of the Past, Present and Future" (Critical Science Press, 2022). Along the way, Vinos comprehensively debunks the IPCC's "wildly extremist" predictions derived from their modelling which deliberately downplays solar forcing and promotes the trace gas CO2 as the driver of climate change.

Over the past year New Zealand has been more exposed than normal to moist tropical airflows from the northeast or "atmospheric rivers" as the media likes to call them. As others have noted, Australian meteorologists had predicted our very wet summer and now autumn as long ago as last October, taking into account the positive Southern Annular Mode, the persistence of La Nina and the disturbance caused by the massive eruption of Hunga Tonga in January 2022. Yet, as you note Karl, such discussion seems to be virtually taboo in this country.

The willful dumbing-down and distortion of science including censorship of views that don't fit the narrative is yet another sign of New Zealand's rapid descent from the first rank of nations into absurdity. Our institutions like NIWA and the universities have failed us.

Trevor Hughes

Mark Hubbard said...

Sorry it's these small boxes LOL.

I meant to put the narrative with that Youtube: I'll try again properly:

'The eruption of a volcano in Tonga may mean the east coast of Australia will have a very wet summer, says Sky News Meteorologist Rob Sharpe.

The Hunga Tonga-Hunga Ha'apai volcano erupted in January this year, blasting vast amounts of water into the atmosphere.

Due to this volcanic eruption and other climate drivers, Mr Sharpe says he’s “expecting this event to go down in the history books as the flooded Summer”.

Mr Sharpe explains in this video how this will occur.'

https://youtu.be/PDQ-EfqTViM

Mark Hubbard said...

Actually: I've read Tom wrong: he's on the Hunga Tonga side of the argument.

Hmm .. sorry. But the clip, thus, explains what Tom is on about, and he's right.

... I need to load up on more coffees.

Tom Chambers said...

Sorry for the delay
https://www.skynews.com.au/australia-news/how-a-tongan-volcanic-eruption-almost-guarantees-a-flooded-summer-for-australias-east-coast/news-story/3b1be3a36b5681ce70d7327392ed0129

Spam said...

For what it’s worth, you might find this link a worthwhile read:
https://rogerpielkejr.substack.com/
Pielke is an expert on economic losses due to natural disasters. He also unpacks the research into climate change and compares it to what the media say. His aim (as per the title of his blog) is to be an “honest broker”. He is of the view that climate change is important to address, but that the outlandish alarmist claims don’t help and need to be called out. His “what the media won’t tell you…” series is very good: there is no proven link between flooding and climate change, and cyclone frequency and power is not increasing (and likely decreasing), for example.

Michael S said...

The media is very shallow when it comes to weather events. Everything is because of man-made climate change (apparently). Whenever the media says "climate change" I prefer to do my own research. Yes, they definitely should remind us that the Tonga volcanic eruption was so massive that it cannot be discounted in affecting weather patterns.

Remember 10-15 years ago the terminology "global warming" was replaced by "climate change" because global temperatures were barely rising. The spruikers of accelerated global warming had egg on their face. Since 1998 global temperatures have barely risen. That's a quarter of a century of scaring people, yet the actual temperatures aren't following the alarming IPCC-led and media-led narrative.

The National Oceanic and Atmospheric Administration (NOAA) and University of Alabama Huntsville (UAH), both leading institutions in temperature monitoring agree that the actual temperatures of the troposphere as measured by satellites (the most reliable method because it avoids the heat island effect on land), shows that the global temperatures are LOWER than all climate forecasting models used by the IPCC.

In Australia the Bureau of Meteorology have been up to many devious tricks that have been documented in the media (manufacturing temperatures rather than recording temperatures) and the Bureau of Meteorology are currently refusing independent scientists access to temperature data recorded at various sites to see whether the new electronic thermometers are measuring temperatures differently to the age-old glass thermometers. They are hiding something. Why the national secret?

I have been following climate data fairly closely in the last 15 years out of self-interest. Apart from receding glaciers, I see no alarm, and even if there was alarming climate change, humankind has the ingenuity to adapt to the environment around them.

The are many reputable sources (too many to mention in a blog)... global temperatures are quite stable, sea levels are barely moving, cyclone frequencies have decreased in the last few decades, cyclone intensities are stable or decreasing, the number of people dying from weather-related events in the last 100 years is in freefall, there is an observable greening of the planet (presumably from extra CO2), crop productions often break new records, and yes, volcanic eruptions can affect climate.

If you hear the media saying "climate change" - don't trust those shallow amateurs - do your own independent research.

Anonymous said...

Karl, I listened to someone this week that said MBIE set up a fund with Covid money called something like the Science and ?? Innovation? fund and that was how the Disinfo project got its money. The fund was initially set up to pay for the promotion of Susie Wilkes and Covid message championing and morphed from there.

I dont know whether it is still being funded by them though as I also read a few weeks back that they made their money from a couple of government contracts initially which have not been renewed this year. They have recently been detethered from AUT? also?

The pundit who discussed this speculated (Perhaps Chris Trotter? or Bryce Edwards) that this genocidal rhetoric was more indicative of their need to keep earning than any kind of rigour or accuracy. Basically, scare everyone with hyperbole and the Govt may flick them some money to carry on paying their salaries.

They really are quite nutty. The stuff out this week equates all slightly conservative NZers with being Alt Right. EG" If you believe the best form of family structure is when kids have a Mum and a Dad then you are alt right and must be censored and shut down before the rot sets in. You dont need to be engaging in hate speech as the small grains of dust your views disseminate will be enough to grow a platform on which violence will sprout.

Clearly, there's some level of desperation there or some level of elevators not going all the way to the top! In any event, anyone who has to shower three or more times daily almost certainly has some OCD thing happening.

Doug Longmire said...

Well said, Michael.
In summary here is the track record of the IPCC;s predictions for doom:-

1/ No 50 million climate refugees by 2010, as they forecast in 2005.
2/ No increase in rate of sea level rising.
3/ Artic Ice is still there, and not melting away
3/ Antarctic Ice is actually growing.
4/ Extreme weather events, world-wide are NOT increasing.
5/ Forest fires, world-wide, are not increasing.
6/ Yes - the planet is slowly warming, in fits and starts, as it emerges from the Little Ice Age of 300 years ago, when the river Thames and the English Channel almost froze over.
7/ The IPCC has recently admitted that it’s multiplying factor used in all their “computer models” is wrong. They were using the highest possible factor, and now admit that it was far too high, and all their predictions up till now have been highly exaggerated (i.e. wrong!)

These above comments are scientific facts - not "denial"

Unknown said...

The Disinformation Project has also failed to respond to my emails requesting information regarding the source of the their funding. As an entity which I'm pretty sure comes under Section 12 of the Official Information Act 1982 they are required by law to respond and I intend to write to them accordingly.

Ele Ludemann said...

While you were having a freakishly wet summer, in North Otago, and most of the southern South Island, we had the sort of weather I remember in summer as a child in the 60s and 70s - day after day of clear skies and sun. Back then we'd have been in drought, thanks to irrigation we could enjoy the sun and still grow grass. Ele Ludemann

Anonymous said...

This is probably the most sensible column I have ever read. It should be published in all the newspapers in the country. I've been trying to tell this to anyone I meet for the last 15 months. Well played sir.

Anonymous said...

It seems Hunga Tonga is not the only potential driver for recent adverse weather events. Interesting article on the ABC website, here:

https://www.abc.net.au/news/2023-05-11/black-summer-bushfires-la-nina-link-found/102196030

Anonymous said...

Further to your link, I found https://www.smh.com.au/environment/climate-change/black-summer-bushfire-smoke-likely-triggered-record-flooding-20230511-p5d7j7.html