Volcanoes melting Antarctica: Why did UN IPCC AR6 report hide the science?

Big glacier began melting before CO2 rose, scud marks on seabed tell the tale

By Ian Wishart

Volcanoes, not CO2, are emerging as a prime suspect in rapid melting of the world’s biggest glaciers in Antarctica, and it appears the world’s leading panel of climate change scientists, the UN IPCC, has deliberately tried to hide the fact from governments, the news media and the public.

At the centre of the scandal is the West Antarctic Ice Sheet (WAIS) which, if it slides into the ocean and melts, could generate a rapid sea level rise of five metres.

The WAIS is currently held in place “by its fingernails”, says Victoria University climate scientist Tim Naish, by a number of big glaciers, including Pine Island, Pope and Thwaites. The three glaciers are the fastest melting in the world, retreating up to 49 metres a day.

Thwaites – around three quarters the size of New Zealand – is nicknamed “the Doomsday Glacier” because if it goes, the WAIS may quickly follow.

Last week, the news website Stuff published a story headlined “Scary new data on the last ice age raises concerns about future sea levels”.

The essence of the story was that researchers found the Eurasian ice sheet retreated at speeds of up to 609 metres a day at the end of the last ice age, as warmer seawater melted the massive sheet at its edges, allowing it to lift off the seabed and float inland with each high tide. By measuring each “ridge” left in the seabed as the ice sheet dropped back down at low tide, scientists could measure how quickly the ice was receding.

According to Stuff, the Eurasian data provided a possible blueprint for how fast Antarctica’s “Doomsday Glacier” (Thwaites) might retreat when global warming really kicks in, calling it “a finding that may shed light on how quickly ice in Greenland and Antarctica could melt and raise global sea levels in today’s warming world”.

Like all good scary climate change bedtime stories, however, the Stuff article didn’t mention a very important fact: Thwaites, Pine Island and Pope glaciers, and indeed much of the WAIS, are sitting on a geothermal powderkeg, bubbling away and melting the ice from underneath.

It’s little wonder that these glaciers are far and away the fastest-melting in the world. Imagine a 4km thick ice sheet sitting on top of Rotorua, and you’ll get a sense of what happens when irresistible heat meets an immovable ice block.

None of this ever appears in New Zealand media stories. On every occasion Thwaites or Pine Island glaciers are mentioned, it is always in the context of carbon emissions causing atmospheric warming causing ocean warming causing melting 700m deep.

Radio New Zealand ran an ABC Australia story last year, for example, that made Thwaites a CO2 canary in the mineshaft:

“There’s no consensus in the scientific community on whether the Thwaites Glacier has already crossed a tipping point where it will be completely lost, regardless of how fast we get emissions down.

“I think there’s been some concern over the last decade or so that this glacier system might have already moved into an unstable configuration,” Professor King said.

Which is where the problem with the “doomsday glacier” moniker comes in.

It implies that the loss of the West Antarctic Ice Sheet, currently being held back by Thwaites, and which will raise sea levels by many metres, is a foregone conclusion.

Under high emissions scenarios, that is most likely the case.

“We’re not going to lose all of West Antarctica and the 5m of sea level that come with it in this century,” Professor King said.

“[But] in some of the high-end [emissions] scenarios, there are some fairly dramatic changes going on in West Antarctica by the middle of the century, and by the end of the century that could be well underway.”

Right now melting of the Thwaites Glacier is contributing about 4 percent of annual sea-level rise.

Under low-emissions scenarios, we give ourselves the maximum chance of stopping catastrophic ice loss globally, Professor Mackintosh said.

“Thwaites Glacier is only one part of Antarctica. Even if we were to lose Thwaites, retarding the current rate of warming would save much more of Antarctica. The same goes for Greenland and for mountain glaciers.

“Even if Thwaites is lost, we need to make it incredibly clear that a high-versus-low-emissions scenario will result in extremely different outcomes for the world’s ice sheets and glaciers.”

How much fossil fuel we burn in the coming decades will directly impact how much and how quickly we lose glaciers and ice sheets.

It all sounds so earnest – no wonder the schoolkids are protesting in the streets. The media, politicians and climate scientists are promising that decarbonisation will stop Antarctica’s biggest glaciers from melting.

But it isn’t true. Not if a deluge of peer-reviewed studies are correct.

The story begins in 2008 with the discovery of an active – and big – volcano under the ice:

“The first evidence of a volcanic eruption from beneath Antarctica’s most rapidly changing ice sheet has been discovered. The volcano on the West Antarctic Ice Sheet erupted 2,000 years ago and remains active. Using airborne ice-sounding radar, scientists discovered a layer of ash produced by a ‘subglacial’ volcano. It extends across an area larger than Wales.

“The subglacial volcano has a ‘volcanic explosion index’ of around 3-4. Heat from the volcano creates melt-water that lubricates the base of the ice sheet and increases the flow towards the sea. Pine Island Glacier on the West Antarctic Ice Sheet is showing rapid change and BAS scientists are part of an international research effort to understand this change.

“Using airborne ice-sounding radar, scientists from British Antarctic Survey (BAS) discovered a layer of ash produced by a ‘subglacial’ volcano. It extends across an area larger than Wales.

“Lead author* Hugh Corr of the BAS says, “The discovery of a ‘subglacial’ volcanic eruption from beneath the Antarctic ice sheet is unique in itself. But our techniques also allow us to put a date on the eruption, determine how powerful it was and map out the area where ash fell. We believe this was the biggest eruption in Antarctica during the last 10,000 years. It blew a substantial hole in the ice sheet, and generated a plume of ash and gas that rose around 12 km into air.”

“The discovery is another vital piece of evidence that will help determine the future of the West Antarctic Ice Sheet and refine predictions of future sea-level rise. Glaciers are like massive rivers of ice that flow towards the coast and discharge icebergs into the sea.

“Co-author Professor David Vaughan (BAS) says, “This eruption occurred close to Pine Island Glacier on the West Antarctic Ice Sheet. The flow of this glacier towards the coast has speeded up in recent decades and it may be possible that heat from the volcano has caused some of that acceleration. However, it cannot explain the more widespread thinning of West Antarctic glaciers that together are contributing nearly 0.2mm per year to sea-level rise. This wider change most probably has its origin in warming ocean waters.”

That was back in 2008. I reported it in my 2009 book “Air Con”. They’d discovered “one” volcano, and despite being a very big volcano there was no reason to change the global warming narrative at the south pole based on one volcano.

But what about 91 volcanoes under the ice? Fast forward a decade and a very different picture was emerging – this from The Guardian in 2017:

“Scientists have uncovered the largest volcanic region on Earth – two kilometres below the surface of the vast ice sheet that covers west Antarctica.

“The project, by Edinburgh University researchers, has revealed almost 100 volcanoes – with the highest as tall as the Eiger, which stands at almost 4,000 metres in Switzerland.

“Geologists say this huge region is likely to dwarf that of east Africa’s volcanic ridge, currently rated the densest concentration of volcanoes in the world.

““The big question is: how active are these volcanoes? That is something we need to determine as quickly as possible.”

In New Zealand, we send climate scientists down to the ice continent every year at huge cost to taxpayers. Why haven’t they told us this?

Victoria University’s Antarctic Research Centre coordinates many studies. Nearly all of them follow the same plotline: Antarctica is rapidly melting because of humanity’s greenhouse gas emissions. West Antarctica, they tell the public, is Ground Zero for cow-belching damage.

If you Google the words vuw, Thwaites glacier, geothermal, melt, only one study by a Victoria University of Wellington scientist comes up – a study from 2015 entitled “High Geothermal heat flux measured below the West Antarctic Ice Sheet” in which Vic Uni’s Huw Horgan was an uncredited contributor.

That 2015 study (the date will become relevant) was the first ever study to physically measure the under-ice heating system, and they found a lake of meltwater under the ice being warmed by around 285 milliwatts per square metre, “significantly higher than the continental and regional averages” estimated by climate computer models.

To put the 285 mW/m2 in perspective, reflected heat from CO2 on the surface of the ice above is estimated at 1600 mW/m2. Traditional global warming theory would have you believe that the 1600 mW/m2 heating of the planet’s surface has directly caused hot water at the base of the glaciers between 600m and 2km underwater. That’s what NZ climate scientists tell the news media daily, and thats what climate change journalists dutifully parrot and repeat to the public in endless patronising “explainers”, and it’s what students from university to primary school are indoctrinated with in classrooms up and down the country.

The stupidity runs rife in our halls of parliament – Greens co-leader James Shaw famously accusing the last National government of “melting Antarctica” by not cutting emissions faster.

But here’s where traditional global warming theory of Antarctic melt hits a reality iceberg. The 1600 milliwatts is not capable of melting ice directly at the ice surface, but somehow retains enough heat despite dissipating through deep ice cold seawater to melt the ice up to 2km underneath?

No. While liquid water at the edges plays some role, scientists much smarter than the koolaid-swilling kiwis have realised that 285 mW/m2 applied directly to the base of the ice sheet by geothermal heat is a lot more efficient at melting ice than 1600 mW/m2 CO2 forcing far above.

A berg in the hand, being slow-cooked over volcanic fires, is an obvious explanation for why these Antarctic glaciers are melting much faster than anywhere else.

Imagine a water slide where you scoot down a slope aquaplaning on a thin layer of water, and you will get the picture. Some of the rapid melt on the edges of Greenland is also driven by geothermal heat – in that case reaching 1000 mW/m2, as a 2019 study by Vic Uni’s Horgan noted “exceptionally high basal melt rates at the head of the Northeast Greenland Ice Stream (>10 cm a−1, driven by geothermal flux exceeding 1 W m−2).”

That 2015 Antarctic study noted the volcanic energy could cause “basal melting” and “the high geothermal heat flux may help to explain why ice streams and subglacial lakes are so abundant and dynamic in this region”.

In 2018 (remember the date, it’s relevant), the US National Science Foundation reported finding helium isotopes created by active, ongoing volcanic eruptions under Pine Island Glacier and the West Antarctic Ice Sheet:

“The researchers first noted the volcanic activity in 2007 and verified its existence again in 2014.

“It remains unclear how the newly discovered activity affects knowledge about the glacier, because researchers don’t yet know how volcanic heat is distributed along the bottom of the ice sheet. However, researchers do know that the heat from the volcano is producing melting beneath the ice sheet. This meltwater is leaking across the grounding line where the ice shelf meets the ocean.

“The heat source, Loose and team note, is about half that of the active volcano Grímsvötn, in Iceland.

“While the effects of volcanic heat on the Antarctic ice sheets is an active topic of research, this study provides the first geochemical evidence of a contemporary volcanic heat source, emphasizing the need to detect and understand volcanism, including in models of ice-sheet behavior. The greater understanding of volcanism could alter scientists’ perception of the mechanics of ice-sheet loss, including in the areas where the glaciers meet the sea.

“Our finding of a substantial heat source beneath a major WAIS glacier highlights the need to understand subglacial volcanism, its interaction with the marine margins and its potential role in the future stability of the WAIS,” they write in the Nature Communications article.

“They also note that volcanic activity could be increasing the rate of collapse of the Thwaites Glacier, which is adjacent to the Pine Island Glacier.

“A complete collapse of the Thwaites Glacier could significantly affect global sea levels, according to scientists. The Thwaites already drains an area roughly the size of the state of Florida, accounting for about 4 percent of global sea level rise — an amount that has doubled since the mid-1990s.”

A NASA climate scientist in 2020 tried to spin his way out of the problem by reassuring the public that volcanoes were just natural background noise in Antarctica and therefore only CO2 warming the oceans could account for the super rapid melt. What NASA ignored is that it’s equally possible volcanic activity is going through a more active phase right now, so the traditional CO2 assumptions may be just a minor part of what we are seeing. At some point when the volcanic field goes ff the boil, the world’s fastest melting glaciers may slow right down again.

Don’t forget: the scientists on the front lines say it is exceedingly difficult to know for sure what is happening under the ice, so beware of “explainers” rushing to play it down as if the issue is ‘well understood’.

As if to prove the point, there’s a crucial line in the 2018 study: “This meltwater is leaking across the grounding line where the ice shelf meets the ocean”.

What that means is the hot volcanic meltwater under the glacier is reaching all the way to the sea, and quite possibly adding to the water heat measurements climate scientists have been blaming on CO2.

In late 2021 (date also relevant), Nature reported further investigation of Thwaites and Pope glaciers specifically:

“We show that the rapidly retreating Thwaites and Pope glaciers in particular are underlain by areas of largely elevated geothermal heat flow, which relates to the tectonic and magmatic history of the West Antarctic Rift System in this region. Our results imply that the behavior of this vulnerable sector of the West Antarctic Ice Sheet is strongly coupled to the dynamics of the underlying lithosphere.”

There you have it. The melting of Antarctica’s big glaciers holding the WAIS in place is “strongly coupled” to a massive 3,500km long volcanic field under the ice.

The final nail in the coffin for the theory that CO2 is behind the rapid melt, comes in another study published in the journal Nature late last year. It revealed that the Thwaites glacier has been retreating rapidly and sometimes much faster for the past 200 years:

“Here we use geophysical data from an autonomous underwater vehicle deployed at the Thwaites Glacier ice front, to document the ocean-floor imprint of past retreat from a sea-bed promontory. We show patterns of back-stepping sedimentary ridges formed daily by a mechanism of tidal lifting and settling at the grounding line at a time when Thwaites Glacier was more advanced than it is today. Over a duration of 5.5 months, Thwaites grounding zone retreated at a rate of >2.1 km per year—twice the rate observed by satellite at the fastest retreating part of the grounding zone between 2011 and 2019. Our results suggest that sustained pulses of rapid retreat have occurred at Thwaites Glacier in the past two centuries. Similar rapid retreat pulses are likely to occur in the near future when the grounding zone migrates back off stabilizing high points on the sea floor.”

Two hundred years.

Let the implications of that set in.

Long before CO2 levels began to rise in the 1950s, something was causing Thwaites to melt twice as fast as it has in the global warming era.

If it wasn’t CO2, it can only have been geothermal heat.

Which brings us back to the fundamental incompetence or dishonesty of the New Zealand mainstream media. Any climate change reporter worthy of the name should know these research studies intimately, but their stories, without fail, either fail to mention that geothermal heat is a big factor in Antarctic melt, or they discount it as irrelevant.

The 2022 Nature study proves the media and NZ climate science community have been spinning us. Until they can plausibly explain what’s been causing major retreat of Thwaites in the low carbon era, we can’t safely give their assurances that CO2 is the definite cause today any credibility.

The media, politicians and climate science outfits like NIWA and Vic Uni’s Antarctic Research Centre need to be challenged on this point every time they try and raise it.

There’s one remaining elephant in the room: the UN IPCC.

On March 20 this year, it published, to huge media fanfare, its sixth assessment report (AR6) on climate change.

The issue of Antarctic ice melt is addressed in the Working Group 1 section of AR6, Chapter 9.

Nowhere, in the 152 pages of that chapter, is the word “geothermal” used in any discussion of Antarctic ice melt. Nowhere.

Instead, the IPCC endorses “with high confidence that melting of ice shelves by warm ocean waters, leading to reduction of ice-shelf buttressing, has driven the observed ongoing thinning of major WAIS outlet glaciers. Since SROCC, digitized radar measurements have shown that the eastern ice shelf of Thwaites Glacier in the Amundsen Sea Embayment thinned between 10 and 33% during the three decades after 1978.”

Not one of the peer-reviewed studies linked in this report is cited by the IPCC in relation to causes of ice melt. It’s as if the studies don’t exist even though all the studies pre-dated AR6.

Vic Uni glaciology professor Nick Golledge is listed as one of 15 “lead authors” on the chapter. He may or may not have had a direct hand in the issue but the IPCC works collegially, so I fired off the following questions:

Hi Nick

I’m writing a piece on WAIS instability and Thwaites.

I note you were a lead author on AR6, WG1 Ch9 and I am very curious to find out why all of you collectively failed to mention anywhere in that chapter the existence of a large geothermal heat flux under that region?

Who made the call to keep that fact hidden, and why?

I will be publishing that I have asked these questions.


Ian Wishart

No answer had been received by publication time.

The UN IPCC urges people to “trust the science”. Based on what is outlined in this report I wouldn’t trust them with a fish and chips order. You can reach your own opinions.

Since February we’ve seen the extreme weather events claim fall apart, we’ve seen extreme rainfall claims collapse, we’ve seen NIWA’s “hottest temperature” data is unreliable, and now we are seeing Antarctic ice melt mythology – a central pillar of global warming theory – taking some heat of its own.

Has the planet warmed since 1850? Unquestionably.

Have humans contributed to that? Certainly to some extent.

Is New Zealand’s climate more extreme now than it was in our cooler past? No, not by a long shot.

Will carbon taxes prevent volcanoes from melting glaciers? No.

Is NIWA’s climate data accurate? No.

Can we trust the IPCC? Apparently not.

Can we trust the news media? No.

Do the media, climate scientists and governments do themselves any favours by exaggerating? No.