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More than 500 people misunderstand climate change

Filed under: — rasmus @ 16 October 2019

A consensus is usually established when one explanation is more convincing than alternative accounts, convincing the majority. This is also true in science. However, science-based knowledge is also our best description of our world because it is built on testing hypotheses that are independently reexamined by colleagues.

It is also typical that there are a few stubborn people who think they know better than the rest. When it comes to climate science, there is a small group of people who refuse to acknowledge the facts that have convinced almost the entire scientific community. Most of these contrarians are not even scientists.

But there are also about 500 scholars who recently have come forward and signed a declaration at odds with the scientific consensus,  claiming “there is no climate emergency”. They represent a tiny fraction of the scholar community dismissing man-made climate change –  by comparison, there is about 20,000 participants on the annual meetings of the American Geophysical Union.

A press conferences has been scheduled on Friday October 18th in Brussels, Rome and Oslo in order to promote the declaration. The intention behind the declaration is to influence the EU and the UN.

Most of the academics who signed the petition have no or little experience within climate research (check Google Scholar). Some of the signatures also have connections with political think tanks.

The message of the declaration is the same that the contrarians have repeated over and over again – but repeating it doesn’t make it more true.

I and some colleagues have examined the most common contrarian papers on climate change and have found that all of them were based on flawed methods/analysis (see previous post Let’s learn from mistakes). Some of the people who signed this petition have demonstrated their incompetence – the proof is in the papers that I and my colleagues reexamined in that study.

We cannot expect every scientist to have the same understanding, especially when it comes to scientific disciplines other than those in which they have professional experience. When they dismiss evidence on matters in an unfamiliar discipline without a convincing explanation, then they demonstrate a lack of respect for both science and the wider public.

They obviously don’t care whether people get true facts of false ideas. Below, I’ll try to explain why their arguments still do not convince.

The following statement is misleading:

“The geological archive reveals that Earth’s climate has varied as long as the planet has existed, with natural cold and warm phases. The Little Ice Age ended as recently as 1850. Therefore, it is no surprise that we now are experiencing a period of warming. Only very few peer-reviewed papers even go so far as to say that recent warming is chiefly anthropogenic”

It is true that Earth’s climate has changed over the past, but such changes have had specific physical causes, which are reasonably well understood. 

There have been changes in the shape of the continents, formation of mountain ranges, changes in atmospheric composition, changes in Earth’s orbit around the sun (the Milankovitch cycles), changes in the sun, volcanic activity, and changes in ocean currents, all of which have influenced Earth’s climate. 

As for the “Little Ice Age”, it was very different to the present global warming. It had a more regional character and was not as synchronised on a global scale as the ongoing climate change. 

The scientific documentation of past changes in climate is one of the ways that we know that that the climate is sensitive to changed conditions. The Earth has never been as closely monitored as today, especially with the help of satellites and advanced modern instruments, giving unprecedented amounts of high-quality data. 

This monitoring shows that the conditions that caused climate change in the past are absent today, except for the increases in greenhouse gases. The IPCC reports provide lists of peer reviewed papers on the global warming. 

The following statement is incorrect:

“The world has warmed at less than half the originally-predicted rate, and at less than half the rate to be expected on the basis of net anthropogenic forcing and radiative imbalance. It tells us that we are far from understanding climate change.”

Indeed, comparisons between simulated and observed global mean surface temperatures indicate a good correspondence.  

I can believe that the people who signed the petition don’t understand climate change, but they should speak for themselves. The rest of the science community has a fairly good understanding. 

The fact that we can write computer code based on the fundamental laws of physics that is able to reproduce phenomena we observe on Earth, indicates that we do understand the climate system. See the description of climate models on both and  

The following statement is incorrect

“Climate models have many shortcomings and are not remotely plausible as policy tools. Moreover, they most likely exaggerate the effect of greenhouse gases such as CO2. In addition, they ignore the fact that enriching the atmosphere with CO2 is beneficial.”

The scientific knowledge underpinning climate policies is established both from observations as well as the laws of physics and climate models. 

The global climate models share common description of the atmosphere with weather forecast models used on a daily basis to provide operational weather warnings. 

All climate models have been evaluated and tested, and they do reproduce the observed global warming as seen with the observations. 

The concentration of greenhouse gases in the atmosphere is increasing. Their physical properties can be established accurately through lab studies.

Carbon Dioxide (CO2) is a greenhouse gas which is a byproduct from the consumption of fossil energy, and the increase in the atmospheric CO2 concentrations represents approximately 40% of the total amount produced from the exploitation of fossil fuels. 

The CO2 bears a fingerprint that connects the increased amount to coal, oil and gas, in terms of the isotopes carbon-13 and carbon-14, as well as the comparable concentrations of oxygen and nitrogen and ocean acidification.  

The climate models reproduce the observed sensitivity, as shown in Benestad and Schmidt (2009) and the figure below.

Fig 2 from Benestad & Schmidt (2014)

Observed 〈T〉 and “all” (thick curves), together with predictions based on equation (1) (open circles) and linear multiple regression models in equation (2) using all known forcings as input (solid circles). Source: Benestad & Schmidt (2009).

The following statement is irrelevant:

“CO2 is not a pollutant. It is essential to all life on Earth. Photosynthesis is a blessing. More CO2 is beneficial for nature, greening the Earth: additional CO2 in the air has promoted growth in global plant biomass. It is also good for agriculture, increasing the yields of crops worldwide”

Water too is essential to all life on Earth. Too much is not good, such as flooding or drowning.

The following statement is incorrect:

“There is no statistical evidence that global warming is intensifying hurricanes, floods, droughts and such like natural disasters, or making them more frequent. However, CO2-mitigation measures are as damaging as they are costly. For instance, wind turbines kill birds and insects, and palm-oil plantations destroy the biodiversity of the rainforests.”

CO2 has an indirect effect on extreme weather conditions through increasing the greenhouse effect and changing Earth’s hydrological cycle. It is well-established that increased surface temperatures lead to increased evaporation and water vapour in the atmosphere. 

Water vapour is the main fuel for weather phenomena such as storms and rainfall. Global warming is also accompanied by changes to the large-scale circulation pattern, such as the Hadley cell, affecting both extreme rainfall in the tropics and drought conditions in the sub-tropics. 

The observed number of record-breaking temperatures and rainfall provide statistical evidence for the weather becoming more extreme. One example is the increased probability of heavy precipitation.

The following statement is misguided:

“There is no climate emergency. Therefore, there is no cause for panic and alarm. We strongly oppose the harmful and unrealistic net-zero CO2 policy proposed for 2050. If better approaches emerge, we will have ample time to reflect and adapt. The aim of international policy should be to provide reliable and affordable energy at all times, and throughout the world.”

There is ample evidence of changing risks connected to weather, with more heatwaves and more extreme rainfall. 

The global mean sea-level is rising and coral reefs are dying. Glaciers providing predictable water supply are melting, such as in the Himalayas. The consequences for ecosystems and agriculture are dire. 

The insurance sector is already affected, and the consequences from climate change will increasingly disrupt new sectors such as agriculture, water management, transport, tourism, and trade. 

There will be regions where people no longer will be able to reside and there will be increased levels of migration and conflicts connected to climate change.

Rather than pushing a petition, the contrarians should present scientific evidence for their view. If such evidence exists, it needs to be transparent so that others can reexamine it and get swayed by the information. So far, the typical contrarians (and one of the signatures) have preferred not to disclose their work.

There have already been some reactions to this petition, e.g. on It was also preceded by a similar Italian “pro-fake-news” petition (signed by more or less the same Italian contrarians as this version) that prompted a response from Italian scientists.

The claims presented in the petition signed by 500 contrarians is the strongest case the contrarians can muster against climate science. In other words, the best shot from the majority of world’s supposedly prominent academics known to have an alternative opinion (i.e. the majority of a tiny minority).

Obviously, there is not much convincing evidence against anthropogenic climate change.



  1. R.E. Benestad, and G.A. Schmidt, "Solar trends and global warming", Journal of Geophysical Research, vol. 114, 2009.

212 Responses to “More than 500 people misunderstand climate change”

  1. 201
    Al Bundy says:

    Ray Ladbury: In fact, as a physicist, I would say that if you are a physicist, then my posterior chews gum.

    AB: Ray? A small request. Please fart.

  2. 202
    nigelj says:

    Looks like Mann was right about the MWP: “The most recent and robust such reconstruction (of the MWP) was completed by a team of over 5,000 scientists from more than 100 countries contributing to the Past Global Changes (PAGES) 2k network, which produced the following chart of global temperatures over the past 2,000 years. It shows temperatures today rapidly rising above the historical record like the blade of a hockey stick.”

  3. 203
    nigelj says:

    “The word “emergency” is not concrete enough to be useful.”

    Would huge emergency be enough to keep you happy? Honestly 10 seconds reading the libertarian drivel on your website was more than I could take. Read your Ayn Rand a bit more critically.

  4. 204
    2D says:

    Precipitation cools the surface of land though. IPCC announced earlier this year floods, droughts don’t correlate with raising CO2. Medieval warm period, dust bowl period had lower co2 than now–we know the medieval warming happened because of viking graves under ice in greenland which was actually green back then. Antarctic sea extent increasing. 17 years no warming recently which ipcc said was because they didn’t know enough about ocean cycles–which is like physicist saying “we didn’t know about gravity.” Litanies of bad predictions, fewer people dying from extreme weather, fewer famines, fewer forest fires. And no the models are not good they can’t even model how clouds, precipitation effect the system reliably and if one of them does, it can not replicate those results through time. Replication proves science, not group think.

  5. 205
    Greta says:

    This article needs some copy-editing. I’d like to share it with my climate-doubter friends, but am kinda reluctant to do so because of all the grammar errors in it, which might discredit it in their eyes. I could mark the errors, if that would be helpful and followed through on. Let me know. :-)

  6. 206
    Cjones1 says:

    The fact is that the AGW proponents have made prophecies that haven’t come true.
    The statements you disagree with are more accurate than those made by bubbly headed AGW proponents. CO2 is one metric in studying climate change in the past, in the present, and in the future. Sokar physicists note that a Grand Solar Minimum is beginning. Total irradiance is lower, the magnetic field is weaker, the poles wander, and predictions are for a cooler climate. These conditions are observable now so the next few years will test the GSM and AGW theories. One thing is for sure – the science is not settled.

  7. 207

    C 206: The fact is that the AGW proponents have made prophecies that haven’t come true.

    BPL: And a lot that have.

    C: [Miasma of denier cliches]

    BPL: Why bother…

  8. 208
    Phil Scadden says:

    Cjones1 – would these “AGW proponents” be part of the science concensus as expressed in IPCC reports, in which case can you point to which “prophecies” that have failed? Would hate to see you falling for a strawman fallacy.

    Would these solar physicists that were predicting cooler climate by any chance the ones that lost that a bet with climate scientist but refuse to pay up?

  9. 209
    Keith Woollard says:

    BPL@207 – you are such a scientist! (not) Go back to writing about religion, or learn about falsifiability.

    If the predictions based on a theory do not happen, the theory is false. It doesn’t matter that some are true

    [Response: You need to read this. – gavin]

  10. 210
    Keith Woollard says:

    Really Gavin? The predictions are wrong because we don’t have enough data? That’s what error bars are for

  11. 211
    Mal Adapted says:

    Keith Woollard:

    If the predictions based on a theory do not happen, the theory is false. It doesn’t matter that some are true

    I’m sorry, but only someone whose scientific education is deficient would say that. Surely you’ve heard of the Dunning-Kruger effect?

    There is much more to the modern philosophy, culture and practice of science than you appear to grasp.

  12. 212
    Mal Adapted says:


    Sokar physicists note that a Grand Solar Minimum is beginning. Total irradiance is lower, the magnetic field is weaker, the poles wander, and predictions are for a cooler climate. These conditions are observable now so the next few years will test the GSM and AGW theories. One thing is for sure – the science is not settled.

    Ah, the accursed, undead “it’s the sun” go-to denialist meme. Have you ever heard of scientific meta-literacy, Cjones1? Why do you trust your sources more than the lopsided consensus of climate specialists? It’s clear you’re not one yourself, you know.

    The embedded graphic at my first link shows the relation between GMST and solar activity over 140 years of observations: astute readers will notice there is none. Speculation about magnetic reversals and climate are just that. And recent published work on future grand solar minima suggests any influence will be local at most:

    For a high-end decline in solar ultraviolet irradiance, the impact on winter northern European surface temperatures over the late twenty-first century could be a significant fraction of the difference in climate change between plausible AR5 scenarios of greenhouse gas concentrations.

    Wanna try again?