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Marcel Crok: The Super Bad Guy Of The Climate Debate

Maarten Keulemans, de Volkskrant

Dutch science writer Marcel Crok is a prominent advocate of the idea that climate change is not so bad. He is now finding a political hearing in Holland.

No, to be invited to address the party congress of a new political party was the last thing, Marcel Crok, climate journalist and long standing and vocal critic of the established order in climate science, had expected: and that (right-wing) party not even of his primary political preference. In fact, you would sooner classify this tie-less, car-less, plain-dressed family man as having greenish, leftist, or pro-animal leanings. But in those circles he is far from welcome, as a climate sceptic with his cross-grained message; but to the right-wing party-leader Thierry Baudet he was. In fact, “I had been so as long ago as in 2011, and before anybody had heard of him,” as Crok recalls. “At the University of Amsterdam Thierry had a small reading club where he invited authors to hold forth on the book they had written. I myself was invited too, and sat there of an evening discussing climate with twenty youngsters; and we have kept in touch.”

In the mean time, in climate matters Crok has developed into a kind of ideologue of this political party “Forum for Democracy.”

At one time, when Baudet had been frightening the man in the street to death by a tweet positing that CO2 is good for the growth of plants, climate is warming slower than expected, and weather extremes still leave us waiting, he sent Crok an app: “that’s how it is, isn’t it Marcel?”

Grist to the mill for Crok, chemical scientist, number crunchier, and author of reports like A Sensitive Matter, How the IPCC hid the good news about climate warming”, or recently “Why the KNMI climate scenario’s will not materialize.” He is trying to organize a “counter narrative”, as they call it: to show another side to the opinions dominant among scientists, politicians and in the media, who are saying that climate is changing dangerously fast, and so we must get cracking, immediately, quickly, and that now!

Crok begs to differ. They are trying to pull us a lot of “green” wool over the eyes, he thinks. “An illusion is being created that there is a climate problem which can be fixed quite easily. And in the meantime a small, but very noisy group of activists is beginning to determine the whole of governmental policy in this matter. Also the application is entirely ideologically coloured: it has to be done through wind and the sun — a CO2-poor option, like nuclear energy is not even on the table. It makes me very cross. This is happening downright undemocratically.”

A huge left-turning conspiracy to the exclusion of the populace: no surprise then that Crok’s criticism is in perfect sync with the Forum for Democracy’s ideology. Earlier on he had been consulted by the (Christian) State secretary for the Environment and the (Liberal) Minister for Economy.

“To this moment nobody has felt any effect of energy transition,” he says. “It was cute, Mr Al Gore saying that we are going to roll back our sleeves and to work on a better world. But it just can’t be done. To decarbonize the economy is an insanely heavy, costly intervention. Germany is the first in beginning to feel the pain. Their industry is moving abroad, they will not achieve their CO2-target.”


“Climate scepticism light” is what this was promptly called — but adherents themselves prefer to call it climate optimism or climate realism. For although Crok may think that we are exaggerating the climate problem and may have an aversion to what he sees as “alarmism” —- you will not hear him denying that the earth is warming and CO2 is contributing to it, or hear him shouting that climate change is a Chinese conspiracy. Instead, he produces statistics, quotes from the UN IPCC-survey reports and duly refers to published studies from recognized science periodicals, even though his opponents accuse him of selective shopping.

We have been acquainted now, Crok and I, for fully a decade. And quite well too: we used to be editorial colleagues at the monthly Natuurwetenschap & Techniek (Science and Technique), now called New Science NL. A cheerful, jovial science reporter of a warm temperament, a good sense of humour and a huge passion to dive into complex scientific issues — features even recognized by his severest opponents.

We were joined in the same editorial job, the same phase in life, the same passion for science and the same aversion to stories of doom and exaggeration. We invented the country’s first fact-check column: “BANG!”(afraid), subtitled: “what is it this month that we are made afraid by?” We discovered that stories of scare in our time —from sickening “dung bacteria”, to gruesome nuclear cancers— frequently derived from environment activist sources and that on closer scientific inspection they were almost always grossly exaggerated.

It angered us. A sense of injustice, that the loudest screamers of doom had their way. A pattern we also noticed in the climate debate then still busy trying to mobilize politics: those who sound the trumpet of doom the loudest get the attention— mentioning bright spots or nuances being prohibited. But while I myself turned the page, embraced new subject matter and resumed my journalistic freedom, he became a “climate reporter” and ever deeper entrenched in the poisonous morass of the discussion.

“My point is” he now says eleven years later, “that on the basis the IPCC you can also arrive at a an utterly positive and balanced view of climate change. Why do we never hear that story? Why does everybody only emphasize the risks, the dangers, the problems? I find it worrying that one side of the story is kept entirely out of the picture.”

That side of the picture in a nutshell is: the earth may be warming at a much slower rate than everybody seems to expect, simply since greenhouse gasses like CO2 are not heating up the temperature so fast, due to all kinds of restrictions and feed-backs in the system. This is a possibility which, fair is fair, does belongs to the realm of science — be it at the very edge of what the IPCC thinks possible, and you will find few scientists who believe in this. But Crok toes the line of, among others, the British scientist Nic Lewis: when you see at what rate the world-temperature has risen since 1860, it appears that CO2 is only providing half as much “warming force” as the climate models indicate — which would mean quite something!

“Of course, there is a real question of warming. It is only some 30 per cent slower than the climate models indicate. Up to 2050, probably only a few tenths of a degrees will be added. And around 2100 there will be a warming of about 2 degrees compared to the pre-industrial period.” Stronger still, according to the calculations of the two of them the warming power of CO2 is so low, that the emission of greenhouse gasses does not have to be reduced very much. “In our opinion, even with an emission just above the level of 2015, we will have in reach, in keeping with the Paris accord, a maximum of 2 degrees warming to the end of the century.”

“But you are almost all alone in your opinion. A survey study in Nature Geoscience even recently called the low warming speed ‘hard to attain’—-a scientifically polite way of saying ‘this is bullshit’. In the meantime, you would have expected more support for your theory if there was anything in it.”

“What I see is primarily a science field very busy with: ‘how can we salvage the climate models?’ Don’t forget: almost al methods in use are based on climate models, which is strange. What should normally be preferred? Observations, of course. But you do not see any preparedness to say: ‘the observational estimates are the best thing we have at the moment.’

That climate models are no good is a popular refrain in climate-doubting circles, whereas the established order is pointing out that observations, hailed so much by Crok and Lewis, are not a good gauge for the future, and that a low warming-speed does not square well with almost everything that is know about the atmos­phere.

We go on squabbling about aqueous vapour, root particles, pre-historic heat waves, volcanic ashes, and tropical heating. But Crok, clever in debate and armed with ten years of technical know- how, is sweeping all objections from the table with the help of literature references, while relishing his sandwich.


 He had just won The Glass Griffin when I first became acquainted with him, consisting of  €10.000 and a sculptured journalistic prize, occasioned by his dismantling an iconic graph showing how the world temperature has been rising from the year 1000: looking like a hockey-stick, with a sudden upward curl since the time of the  greenhouse gasses—as it was presented and claimed, amongst others, by the IPCC, which presented the graph in a prominent position. But Crok had spoken to two researchers who had proved that it contained a statistic mistake: whatever data you enter into it, a hockey-stick will always come out. So Crok writes on the front-page of his report in tall script: “The proof that man is warming the earth does not wash.”

Even then this was contested. He was said  not to have been critical enough. “Crok accepts it from them, joins them in anger, but has not figured it out”, grumbled this daily newspaper De Volkskrant. “Crok offers half a story with a lot of noise.” He was booed while receiving the award.

This touched something in him. He had worked at it for months on end. He had been to Hamburg, had adduced an indepen­dent statistics expert to recalculate the whole thing. Was there any part in the story that was not to be told? “In the end it is all about the cool, verifiable numbers, is n’t it? If you wish to  understand me, this is the beginning,” he says after­wards. “My first story about climate, and it started immediately: Marcel Crok is a climate sceptic; Marcel Crok only looks at one side of the story. I did not know what befell me.”

This is how he came under the spell of the counter voice; not so much attracted to it—rather pushed into it., as he sees it.  “The planet gets frizzled up. We are all going down the drain, and whoever is asking questions is a grumpy and havoc-making guy. It triggered me no end”, he recalls. “If a prominent piece of evidence like the hockey-stick is shaky, what then about the other claims? I wanted to understand the whole discussion.” He quit his editorial job, was going to use the prize money to  write a book about academic climate criticism and went out into the world, in search of scientists whom had he heard the same ban proclaimed on as on himself, angry and making amok. He did not have far to seek. The politocologist Roger Pielke, jr., who had half the world at his throat after he had established that cyclones are not getting more violent.; Judith Curry, Professor of Climatology, who noticed that climate science is dominated by a clique of cocks covering for each-other; Henrik Svensmark, the Danish  physicist,  who has an exotic theory about cloud-formation by cosmic particles.

These were the outcasts from the climate debate, Crok realized. And no, they did not all tow the line of the oil industry, and breathing heavily like Star Wars’ villain Darth Vader, they did not do either.


“Welcome to the Dark Side, Luke.” Irritated by the quotation from Star Wars : “Why do you have to call it the Dark Side? Is that what it is? Anyone who does not support the consensus to the full, is instantly suspect, belongs to the ‘bad guys’, has to be cast out. The result is that all criticism is pushed to the margin: Dark Side, take care.”  “But not quite without justice? Particularly in the United States there is a strong lobby to put climate science in an unfavourable light.” “Oh, that story has become so out of date in the meantime. When Matt Nisbet of Northwestern University was figuring out what the truth is about those reputed floods of money behind the climate lobby, he discovered to his amazement that more money was present on the pro-climate side—the Al Gore camp. Yes, there is money too on the fossil side, except that this does not go to climate scientists, but just to the political lobby in Washington. All those well-known climate critics: Nic Lewis, Steve McIntyre, Henrik Svensmark, Judith Curry, Roger Pielke jr., Richard Lindzen — do not get a single penny from the oil industry”.

“But you did get some wrong friends. You were writing for the Global Warming Policy Foundation, a right-wing (sic) think-tank whose aim it is to expose extremely harmful climate policies, under the leadership of a sour old right-wing Briton, Thatcher’s ex-energy minister Nigel Lawson.” “But I am not saying that this is ideal, in fact the question is: where can you get a critical report, such as Lewis and I wrote, published? Hardly anywhere. So what happens? You are driven into each-other’s arms,”

“But you are a journalist. So you approach a newspaper, when you observe something wrong.?” “Yes, but which? I have approached nearly all newspapers and several magazines. Every time it was: sorry, we think that you have a too outspoken position in the debate. They mean to say, a wrong position. Expertise plays a minor part in this matter; it hinges primarily on the message you are sending. To be critical about climate is not a good earning model.”

In the meantime Crok is sometimes also writing for the weekly Elsevier magazine. In this newspaper, De Volkskrant, he did publish a plea for nuclear energy. Sour smile: “ironically, I live like a green-left-wing guy. I have no car, hardly any income, do everything by bike. Sometimes I think: what if everybody became climate-critical my way, that would leave our carbon-footprint a lot lower.”

Suddenly open-hearted: “in 2015, prior to the Paris climate accord, I realized more and more that I have become a lone voice from the desert. And let me just admit: it is not easy to be that. At a given moment you think: what am I doing? No one will listen to this. You are just being cornered; you don’t belong.”

“Climate criticism does go before the wind with Donald Trump and Thierry Baudet, doesn’t it?” “Now and then, some politicians come to the surface who dare sing a counter tune. But these two do serve as exceptions. if in whatever way they are voicing criticism on the climate story, they are immediately scoffed at—it’s a shame. When Trump opted out of the Paris climate accord, the whole world put him to shame. That is what we have to deal with in this debate. You have the good guys and the bad guys. And I am the super- bad guy of course. I do not actually believe that CO2 is such a problem.”

“During the preparation of this interview there were indeed people saying: do not grant him this platform.” “Yes, what can I do about it?” “At the party congress of the Forum for Democracy you were saddled with an outright screamer: ‘that climate sceptic Crok should happily join the [ultra rightwing Geert Wilders] Party for Freedom, someone from the audience yelled at you.”  “The forum is under fire, of course, on account of its immigrations views, but sustainability even triggers much deeper emotions than the Islam does. Somehow, I do understand this: people worry about the future of their children and grandchildren, but what I don’t understand is that subsequently they put me in the corner of the bad guys, as if I do not wish the very best for my children and grandchildren.”

“What you are reproached for is primarily your one-sided­ness: you always put the stress on one side of the story, while the risks, from melting poles to waves of refugees are certainly not lying.” “This might possibly be my sort of counter-reaction to all those stories of doom.  My feeling tells me that this is because the Weather Bureaux of this world are only telling one half of the story.”

“Don’t you now think you have become an activist yourself —but then against climate policy?” “I do not see myself as such. Nor am I against climate policies, but mine would look entirely different, with much greater emphasis on adaptation to climate change and less to extremely expensive measures to reduce green­house gasses. I find it somewhat uneasy to brook the injustice of not hearing to whole story. Take the Dutch political Energy-Accord: the minister of economy has never told what the total costs would be. Nobody knows! In fact, it may be well beyond 100 milliard Euro’s.  There has not been a single debate in Parliament about it, nothing.  I find that shocking. All the cards should be on the table, the uneasy ones too.”

“Wait,” he suddenly says, he had printed out some matters, producing a pile of colourful graphs. “Here, the deathrate from starvation, rrrrr: down; world poverty, rrrrr : down; deaths caused by natural disasters, dwindled almost to zero.” His fingers rest at the bottom of the statistics. “And today, just as it the world is doing fantastically, everyone starts being hysterical about climate change. The  large line is:  greater prosperity, better health, higher agricult­ural produce, but the IPCC tells you: warming causes the agri­cultural produce to go down. Pardon me!”  Quasi astonished look! “What they mean is: agricultural produce is steadily rising, but when we run our models, we see that owing to climate change it is perhaps a little lower than otherwise.”

He waves his arms, his voice is rising in indignation: “Come on boys! Do just tell us that fucking story!”

Scientists do not agree with Crok

Indeed, it is conceivable that Lewis and Crok are right and that the earth is warming more slowly: this chance is about 1 in 20, according to the latest IPCC report. But, so say six climate experts who were consulted by de Volkskrant independently from each other:  but this is now ‘untenable’, ‘indefensible’ and ‘physically unrealistic’.

‘There are basic errors in the method that Lewis is proceeding with’, ass Björn Stevens of the Max Planck Institute for Meteorology in Hamburg mails to us, at our request. ‘Probably no errors that are so great that they make the method useless. However, they do colour the results.’

How greenhouse gases can provide more heat is still unclear. The IPCC uses a ‘climate sensitivity’ between 1.5 and 4.5 degrees: i.e. if you double the amount of CO2 in the atmosphere, the atmosphere will ultimately become between 1.5 and 4.5 degrees warmer. In practice, this can make the difference between warming that is quite o.k. and unavoidable climate disaster.

Although many recent studies result in a middle average of about 3 degrees of warming per doubling of CO2, Lewis and Crok point out that the warming experienced so far indicates a much milder warming of about 1.6 Celsius per doubling, Crok and Lewis point out that the warming actually measured seems to indicate a more limited warming, of 1.6 degrees. Some other analyses too seem to confirm that warming is taking place more slowly, although the difference is well within the coincidence margin.

This does not mean that Lewis and Crok are right. ‘Marcel might have a point that models predict more warming than we see in the data’, says Guido van der Werf, Professor earth sciences (Free Univ. Amsterdam), ‘but I think the difference is much smaller than he pretends.’ He himself used a method similar to the one of Lewis and Crok: he ended up with a warming that is hardly slower than the models indicate. ‘The best you can say about it, is that the historical warming is difficult to reconcile with a high climate sensitivity of 3.5 C or higher’, Stevens admits.

Others says Crok’s view of the issue is one-sided and biased. ‘Marcel ignores three lines of evidence which exclude a climate sensitivity lower than 1.5 C. And even then he chooses the absolute lower bar of what might be possible’, says Pier Siebesma, Professor of earth sciences (Technical Univ. Delft).

‘You just cannot sweep other estimates for climate sensitivity, such as those based on prehistoric data, under the carpet’, says also Wilco Hazeleger of the eScience Center in Amsterdam. Bart Verheggen, Amsterdam University College: ‘With a climate sensitivity of only 1.5 C you simply cannot explain that the earth’s climate changed so drastically in the distant past.’

Bart Strengers of PBL (Netherlands Environmental Assessment Agency) participated in several public debates with Crok. ‘The sceptic, that’s me actually’, he believes. ‘Marcel follows one specific line of evidence, whereas I look at several methods and do not defend one specific view.’

By Maarten Keulemans, de Volkskrant

Translation: Kees Schoneveld

this translation is published with permission of de Volkskrant

Marcel Crok: