Peter Hadfield versus Tom Nelson

This article not directly related to Arctic sea ice, but instead is one of our (very!) occasional series on the psychology of anthropogenic global warming “skepticism”.

Peter Hadfield is better known as the man behind Buster Keaton’s face on the “Potholer54” channel on YouTube. Tom Nelson is the “producer” of Martin Durkin’s “Climate: The Movie”. Peter produced a video criticising that movie. Many months later Peter and Tom have just recorded a “long-form, man-to-man debate” via Zoom about those criticisms. Here is episode 1 of Potholer’s version of events:

Here is “Snow White’s” hot take on the first 10 minutes of Tom Nelson’s version of events on X (formerly Twitter):

In brief, Tom seems to be incapable of providing a straight answer to a straight question, and instead loudly rails against what he continually refers to as the instrumental temperature “spike of doom”.

Can you spot the difference between these two graphs? The first is from Ljungqvist (2010):

The second is from Climate: The Movie (The Cold Truth):

[Update – May 5th]

Note that at 2:18 in the video above Tom says:

I want to make sure that my audience hears everything that you have to say, so I’d hope that we don’t filibuster and try to keep our answers short and snappy.

Here’s the second episode of the Peter v Tom “debate”:

Would anybody here care to run a stopwatch past the time spent “filibustering” by each of the two participants?

In the video description Peter has this to say:

During the debate, Tom asked me a gish-gallop of questions, including whether I ‘believe’ CO2 is the control knob of global temperature, and about the Medieval Warm Period, and the weather, etc. He did not choose any of these as topics for the debate…

So why didn’t I simply answer all his questions and explain this? Because I have had 40 years experience interviewing politicians and government officials, whose strategy is always to divert attention onto another subject whenever you are homing in on a contradiction or a mistake. Even if I had taken the bait and explained what the science actually shows regarding the weather, or the control knob, or the MWP, as soon as I got close to busting another of Tom’s fallacies, he would have interrupted me mid-sentence to try to divert onto another subject. The trick is to always keep them on the topic.

Here’s are Peter’s subsequent musings on the “debate”:


Here’s an excerpt from Peter’s conclusion at ~ 13:40:

People who lobby for industry and vested interests don’t want to discuss the science, they want to support their beliefs. If you agree with their beliefs you’re on their side. If you don’t agree with their beliefs you’re on the other side.

If changing graphs, airbrushing out contradictory information, hiding sources and misrepresenting studies is what it takes to support those beliefs, then it’s perfectly OK.

If the other person is trying to make a point that gets to the facts and the reality, then do everything you can to interrupt, filibuster and deflect. What matters outside the world of science is not getting to “the truth”, but what they call “winning”.

Unfortunately for Tom Nelson, Martin Durkin and the CO2 Coalition, the internet keeps receipts of airbrushing:

Facts About the Arctic in May 2025

JAXA/ViSHOP extent is no longer “lowest for the date”! After “flatlining” for most of April the metric is now in the midst of a close knit group of the other years in the 2020s:

The high pressure area over the Central Arctic persisted through the second half of April, and so did the consequent drift of ice from the Pacific side of the Arctic to the Atlantic periphery:

AWI’s sea ice area for the Greenland Sea is currently “highest for the date” in the AMSR2 record that started in July 2012:

The offshore winds along the Laptev Sea coast have continued, and sea ice area is now “lowest for the date”:

The first signs of a break in the high pressure dominance are appearing. GFS currently forecasts that a low pressure area will enter the Central Arctic, bring above zero temperatures over the Kara Sea on Sunday:

Continue reading Facts About the Arctic in May 2025

Facts About the Arctic in April 2025

JAXA/ViSHOP extent finished the month of March “lowest for the date” once again:

However, since then the graph has been “flatlining” and extent is now above 2019 and rapidly approaching the rest of the recent pack.

At the end of March PIOMAS Arctic sea ice volume had increased to 21.21 thousand km³, still 2nd lowest for the date in the PIOMAS record:

Here is the corresponding PIOMAS sea ice thickness map for March 31st 2025:

For comparison purposes, here is the “near real time” CryoSat-2/SMOS merged thickness data from the Alfred Wegener Institute: 

Continue reading Facts About the Arctic in April 2025

The 2025 Maximum Arctic Sea Ice Extent

The time has arrived to start taking a close look at the assorted different Arctic sea ice extent metrics, in order to ascertain their respective maxima for 2025. To begin with here’s Zack Labe’s overview of previous years’ maxima:

It now seems highly likely that 2025’s maximum extent will ultimately prove to be the lowest in the satellite era. The remaining question is when this year’s maximum will occur.

My speculation yesterday that AWI’s flavour of Arctic sea ice extent had already achieved its maximum value for 2025 has been negated today:

The NSIDC 5 day average and JAXA extent metrics are also currently at their maximum levels for the year so far, so let’s wait and see which one is the first to take a downward turn.

[Update – March 28th]

The National Snow and Ice Data Center have called the maximum extent of Arctic sea ice for 2025:

On March 22, Arctic sea ice likely reached its maximum extent for the year, at 14.33 million square kilometers, the lowest in the 47-year satellite record. This year’s maximum extent is 1.31 million square kilometers below the 1981 to 2010 average maximum of 15.64 million square kilometers and 80,000 square kilometers below the previous lowest maximum that occurred on March 7, 2017.

Continue reading The 2025 Maximum Arctic Sea Ice Extent

Facts About the Arctic in March 2025

After spending several weeks in the unfortunate position of lowest for the date, JAXA/ViSHOP Arctic sea ice extent has just risen above 2015. By a mere 10,000 km²:

Despite the fact that JAXA extent is still rising, AWI extent has potentially already achieved its maximum value for 2025:

Somewhat belatedly, here is the PIOMAS sea ice thickness map for February 28th 2025:

At the end of February Arctic sea ice volume had increased to 19.32 thousand km³, still 2nd lowest for the date in the PIOMAS record:

For comparison purposes, here is the “near real time” CryoSat-2/SMOS merged thickness data from the Alfred Wegener Institute: 

AWI have also released a new version of their thickness product, incorporating additional data from the two Sentinel 3 satellites. The thickness data for February 28th, looks slightly different:

Continue reading Facts About the Arctic in March 2025

Facts About the Arctic in February 2025

This isn’t exactly “shock news”, since we (slightly hesitantly!) predicted this 5 days ago.

A GFS 2 meter temperature chart revealing greater than zero degrees Celsius at the North Pole later today:

The 2 meter temperature anomaly at the Pole is almost off the charts:

Plus the cause of these unusual numbers, a cyclone with central pressure of 959 hPa spinning north of Ellesmere Island at 18:00 UTC this evening:

All of which has led to the JAXA/Vishop Arctic sea ice extent being the lowest for the date since 1979 at least by a significant margin:

Continue reading Facts About the Arctic in February 2025

Facts About the Arctic in January 2025

The New Year began with JAXA/ViSHOP extent lowest for the date in the satellite era, just below 2018 . Since then extent has reduced, and there is now a large gap:

The primary reason for this is the remaining open water in Hudson Bay:

In previous years Hudson Bay has been covered by sea ice by this time of year, but in 2025 a large area remains unfrozen in early January!

Due to the way PIOMAS handles the leap years the last gridded thickness data of 2024 is dated December 30th:

By December 30th Arctic sea ice volume had increased to 13.61 thousand km³, 2nd lowest for the date in the PIOMAS record:

Continue reading Facts About the Arctic in January 2025

Facts About the Arctic in December 2024

Christmas is coming, and even as we speak Snow White is heading for the geographical North Pole to assist Santa’s little helpers in their annual gift delivery mission:

Santa at the North Pole in August 2016

We’ll start the festive season with a graph of JAXA/ViSHOP extent, which is in a “statistical tie” with 2020 for 2nd lowest for the date in the satellite era:

Here’s the PIOMAS gridded thickness data for the end of November 2024:

On November 30th Arctic sea ice volume had increased to 9.99 thousand km³, 3rd lowest for the date in the PIOMAS record:

For comparison purposes, here is the “near real time” CryoSat-2/SMOS merged thickness data from the Alfred Wegener Institute: 

Continue reading Facts About the Arctic in December 2024

Facts About the Arctic in November 2024

The Laptev and East Siberian Seas have now refrozen. Consequently Arctic sea ice extent is now increasing more slowly, and JAXA/ViSHOP extent is 3rd lowest for the date in the satellite era:

Introducing the third dimension, here’s the PIOMAS gridded thickness data for the end of October 2024:

Note the change in scale from previous months, to allow for easier comparison with the “near real time” CryoSat-2/SMOS merged thickness data from the Alfred Wegener Institute: 

Continue reading Facts About the Arctic in November 2024

Facts About the Arctic in October 2024

The JAXA extent graph is currently not updating, so let’s begin this month with the latest AMSR2 sea ice concentration map from the Alfred Wegener Institute. Click the image to see a ~10 Mb animation of the last four weeks:

Note in particular the restart of export into the East Greenland Sea via the Fram Strait:

and the movement of ice within the Canadian Arctic Archipelago:

The PIOMAS gridded thickness data for September 2024 has been released:

Continue reading Facts About the Arctic in October 2024