RIP Hans Schreuder, Analytical Chemist & Sky Dragon Slayer

Written by John O'Sullivan


On December 4, 2019 Hans Schreuder, scientist and renowned independent climate researcher, passed away while on a visit to Thailand.

Best known as the co-founder of the ‘Slayers’ – a rising force in the climate debate who insist CO2 is not our climate’s control knob and likely cools, not warms the atmosphere.

From the outset, the retired Dutch Analytical Chemist was a key figure among the ‘Slayers’ as they set about exposing grave flaws in the greenhouse gas theory, for 30 years the cornerstone of consensus climate change science.

For me, Hans was the biggest inspiration, alongside the indomitable Alan Siddons, to devote my last ten years on this critical mission. A friend greatly missed Hans compiled a vast online resource of skeptic science on his blog,

Without his ceaseless encouragement and resolve we may not have succeeded in establishing Principia Scientific International, now recognised worldwide as a hub for independent scientists extolling the traditional scientific method.

I first met the bespectacled, baseball cap-wearing Hans in person in 2009 through mutual friend, Gabriel Rychert. It was a large gathering inside the Houses of Parliament, London, at the Climate Fool’s Rally in October 2009.

With a beaming smile the tall, lanky Dutchman introduced himself with a firm shake of my hand and he charmed everyone with his distinct Dutch accent and belly laugh.  Among us climate realists gathered that day, his good-humor and sharp intellect shone out (not surprising being a member of MENSA).

Image may contain: 1 person, standing and suit

Hans had kindly paid for and brought that day an enormous printout of a check for $10,000 from our generous book publisher, Ken Coffman of Stairway Press (see photo above). Rather than do the honors himself, Hans wanted me to present it to world-leading independent long-range weather forecaster, Piers Corbyn (older brother of Labour Leader, Jeremy).

As was his way, the naturally introverted Hans insisted others take the limelight while he busied himself behind the scenes forming new friendships, enlisting fresh support for our mission.

Buzzing from the success of that day Hans and I threw ourselves into compiling and editing the manuscript of the ground-breaking book, ‘Slaying the Sky Dragon: Death of the Greenhouse Gas Theory.’ Mr Schreuder possessed a keen eye for detail and gave his all editing and polishing the book.

Over the ensuing decade we had many ups and downs. Hans was relentless in his activism and would write literally hundreds of letters to authorities, politicians, academics, fellow skeptics all over the world.

For several years Hans fought prostate cancer. He visited me here in Wales last summer and was as always self-depracating and good-humored. We enjoyed lively conversation, good food and hopes for a better future for open and transparent scientific discourse.

Never was he one for self-pity or blowing his own trumpet. Mr Schreuder was the archetypal team player – ‘collegiality’ was his watch word. He had immense disdain for pompous, glib authority figures and was adamant that society’s reverence for status over aptitude fueled the rampant man-made global warming fraud.

Schreuder and Siddons – not feted at all in the academic world – were instrumental in sowing the seeds of skepticism over claims that a trace gas, carbon dioxide ( CO2 ) was the climate’s control knob.

From his own extensive research and professional training, Schreuder was one of the first scientists in the world to recognise that CO2 serves to cool, not warm our climate. In the past three years we worked diligently on the follow-up to our first book.

To be titled, ‘The Sky Dragon Slayers: Victory Lap’ it was self-evidently triumphant in tone, regaling the vast body of scientific studies and discoveries of recent years that vindicated our seminal work back when the only topic of debate among alarmists and lukewarmers was ‘how much’ was carbon dioxide warming the planet. We climate realists now have the ascendancy.

Hans gave many hundreds of hours selflessly helping compile the new book. He never got to see it published, but would have been mightily satisfied by the end product.

Today, any sensible, open-minded soul reading our work can see for themselves that the idiosyncratic Dutchman was right all along – the best empirical evidence (forget computer models) proves CO2 is not our climate’s control knob – all it does is cool, never warming anything, least of all our magnificent blue, green planet.

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Comments (9)

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    Sad news. Hans often contributed on various blogs. I always enjoyed his informed comments. He was a real “Climate Hero”.

    Thanks for sharing the additonal information about him.

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    J Cuttance


    Sad news indeed. Our corner can ill-afford the loss of such a scientific heavyweight.

    Sincere condolences.

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    Ken Coffman


    What a sad note. Hans had an incisive mind and was one of the pioneers in recognizing that not only does rarefied atmospheric CO2 do nearly nothing, but the sum result of its affect might be cooling…and that its presence in our atmosphere is a great benefit to greening the Earth. RIP, Hans.

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    Andy Rowlands


    I am sorry to hear of the death of Hans Schreuder before he got to see the updated Slayers book. I remain honoured to be invited by John O’Sullivan to contribute a small part of the book.

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    K. Kaiser


    Sad to read of Hans’ passing.
    RIP, my friend!

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    Joseph Olson


    The Truth community has lost a valued contributor to restoration of the traditional scientific method. Hans set up my website, shaped and focused my research through hundreds of emails. I regret never meeting him in person, to tip a pint to the merry band of Slayers.

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    Robertt Beatty


    RIP Hans,
    You fought a good fight and landed many telling blows. Now the battle continues with ‘draining the swamp’ and beating the ‘resist movement’.

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    John Alexander


    So sorry for his loss condolences to friends and family

Comments are closed