Atmospheric Sciences Editors' Vox

Responding to Climate Change Deniers with Simple Facts and Logic

A sequence of five questions and answers that can be used by scientists to communicate some simple concepts of climate change to broader audiences.


Many of our colleagues, and concerned citizens, have asked how to respond to climate contrarians who claim that they don’t “believe” in climate change, or have fallen prey to disinformation publicized by those with vested interests in fossil fuels and related industries. In some cases, simple facts and logic can help such people understand the realities of the earth system and how it is responding (and will respond further) to anthropogenic perturbations such as greenhouse gas emissions.

However, there are many others for whom this approach proves ineffective. Holding a worldview that would seem anathema to any scientist, many of our fellow citizens do not use direct observation, evidence, or science in general, as their primary basis for decision-making. No amount of factual education can alter this worldview, and it has become clear that other means must be found to prevent this segment of the population from making self-harming decisions, whether induced by disinformation or otherwise.

Some of these issues were articulated in a special session at the recent AGU meeting on Climate Literacy. In one presentation, Naomi Oreskes suggested that the human brain’s decision-making centers are more closely related to emotional centers than they are to rational thought and reasoning, citing the 19th century “miracle” case of Phineas Gage as a rare example of the link between emotions and decision-making. While people do not typically have iron rods driven through their heads, this further supports the general theme that emerged from the AGU session that a significant segment of the population will respond better to emotional messages than to factual information. As a scientific community, we are a long way off from being able to communicate on that level, yet it appears that a way must be found.

Meanwhile, for those who may respond to a logical sequence of reasoning, the following questions should be asked and answered in sequence. Hopefully this can assist the scientific community in communicating some simple concepts to broad audiences.

1.  Is climate changing?

Yes. Scientific observations and measurements have provided undeniable data that show temperatures have been rising, precipitation patterns have been changing, and ocean and atmospheric circulation systems have been changing throughout the 20th and 21st centuries.

2. Do people have anything to do with it?

Yes. Greenhouse gas emissions (primarily carbon dioxide from fossil fuel burning) have to warm the atmosphere—it is what they do. The consensus of model results shows that the global climate is sufficiently sensitive to historic anthropogenic carbon dioxide emissions to have already warmed by the amount measured over the last 150 years. In addition, carbon dioxide triggers a water vapor feedback, greatly amplifying the effect, as warm air can hold more water vapor than cold air.

3. Is climate change bad?

Yes. While this is a more normative question to be considered by philosophers and the general public rather than by scientists, history has shown that any change in the environment of stable civilizations is disruptive to those civilizations. Alterations in areas in which crops can be grown, changes in phenology (when plants bloom or flower, when leaves fall, when insects emerge, etc.), shifting storm tracks, and rising sea level may have devastating economic, social, and political consequences on modern societies.

4. Can we do anything about it?

Yes. Because much of the warming caused by past emissions has already occurred, cessation of emissions can stabilize climate in the 21st century. Until they are overwhelmed, natural carbon sinks in the ocean and terrestrial ecosystems can continue to absorb previously emitted carbon and return global climate to the stable state in which civilization evolved over the last 10,000 years.

5. Is it worth doing anything about?

Yes.  Economic analyses indicate that the cost of adaptation to climate change in the form of agricultural disruptions, damage to coastal cities and infrastructure, and impacts of extreme events will be much greater than the cost of mitigation by transition to sustainable energy sources.

What we learn from the past is that nearly every major climate change in Earth’s history has been accompanied by changes in greenhouse gases, with warming associated with more carbon dioxide and cooling associated with less. In the geologic past, before humans existed, climate and atmospheric carbon dioxide concentrations varied together, with carbon dioxide change not always predating climate change. This was due to the runaway feedbacks between temperature, carbon dioxide in the atmosphere and ocean, and water vapor in the atmosphere. However, now that we have devised a way to inject carbon dioxide directly into the atmosphere (fossil fuel burning), carbon dioxide is preceding climate warming, which is already responding to the additional greenhouse gases.

–Dork Sahagian, Department of Earth and Environmental Sciences, Lehigh University; email: [email protected]

  • Bob Young

    What a bunch of bull poop this is! Of course climate has been changing, but for billions of years, not just in the 20th and 21st centuries. BTW, climate change is very good, unless you wanted to live on top of two miles of ice that covered much of North America and Europe a mere 10 to 15 thousand years ago.

  • bookspeople

    The comments are excellent and address a critical goal. Just to add:

    Convincing everyone that climate change is real and a threat to them is hard because the obvious, direct effects in our temperate zone are not yet…”undeniable”. Consider the threat of a pandemic of some disease with expensively-treatable, subtle and ambiguous initial symptoms, yet catastrophic final stages. How many people- particularly the wealthy or powerful- would risk loss of jobs, position or investments to mount an all-out effort against it until the effects were unavoidable?

    Who do we trust? Few (except for us devout nerds) will wade through journal articles and clear evidence after a long day at work, especially when few in authority seem concerned. Instead, most folks will turn to the TV newsreader quoting a political chieftain who has other fish to fry- and who certainly hasn’t read the journals either. After a steady bombardment of disappointment, scandal, outrage (real and manufactured) and diversion, I really don’t think there is anyone who everyone will listen to when he (or she) tries to rally the citizenry.

    Crisis saturation. There is such a bleating chorus of those crying “Wolf”, that people are tired of it all. “Aiiiee! Russians! Chinese! Immigrants! Fracking! Fukushima! Mad Police! GMO’s! Terrorists! Gluten! Layoffs! Overpopulation! Nukes!” The quiet rational voice saying, “Anthropogenic CO2 Emissions are causing an escalating climate crisis which will destroy our civilization and we can prove it.” doesn’t stand a chance. And, maybe we really are surrounded by a large ring of wolves and what’s one more, eh?

    Society and government are in the midst of an evolutionary spurt right now. New relationships and power structures are forming worldwide. As things settle- hopefully soon- leaders and peoples will turn to science as a dependable base for policy and planning. We need to preserve, adapt, and keep the faith.

  • MacUndecided

    As you can see all comments of a dissenting nature are deleted from this site. And now you have proof of the censoring that takes place in the scientific community.

  • MacUndecided

    Why is it that the AGW climate change alarmists always tout the last 800K years of the CO2 record but completely ignore the CO2 record that extends beyond our current ice age? I know this comment will be deleted by the censors on this site and that is sort of the whole point of making it. For most of earths history CO2 levels have been 2 to 4 times higher than they are today. CO2 has been in decline for most of the lass 100 million years. But all measurements taken by the AGW proponents are from the tail end of the ICE age we currently find ourselves in. They completely disregard the longer history. And so if you take all your measurements from one of earths coldest periods and pretend that is the entire history of earth, then the current temperature changes can be made to appear very alarming.

    But CO2 is actually making our planet greener. It is better for plants and thus better for us all. Trying to preserve the ice age simply because man seems to be bringing us out of it through the burning of fossil fuels is absurd. The people who promote this view should be disregarded as flakes.

    • Geoff Offermann

      The simple fact that the present phenomenon diverges from the paleo record should give you pause.

  • MacUndecided

    If my comments continue to be censored I am going to share this site with every skeptic I know. So that they can share this site with everyone they know and maybe make a Youtube video of posting comments that run contrary to the narrative to show how sites like this censor dissent. The video will do a lot to destroying the AGW narrative, because it shows the hypocrisy of the group thinkers here. I have watched several of my comments that raise important questions be deleted. Time to shine the light on this site. Go ahead censor keep deleting my comments, see where it gets you in the end, your site will be flagged as just another false science site.

  • MacUndecided

    So here is a question to all of the AGW faithful. Beyond 2.5 million years ago which is about the time our current ice age began, what if any tools are used to determine the level of CO2 in the atmosphere, keeping in mind that animal life began evolving on this planet around 300 million years ago?

    • qb

      It seems no one is interested in responding to your questions .
      They appear to be legitimate, and even pertinent questions which need to be addressed, before the unenlightened non scientists such as myself, can fully understand the AGW CO2 argument.

  • Doordenker

    Do people have anything to do with climate change? This article fails to answer the big question ‘how much’.

    • CB

      “Do people have anything to do with climate change? This article fails to answer the big question ‘how much’.”

      Answer it yourself:

      Humans have raised the level of CO₂ in the air from roughly 280PPM prior to the industrial revolution to 407PPM today.

      If this isn’t going to be enough to melt the polar ice sheets completely, why isn’t there a single example in Earth’s history of polar ice sheets withstanding CO₂ so high?

      “The continent of Antarctica has been losing about 118 gigatonnes of ice per year since 2002, while the Greenland ice sheet has been losing an estimated 281 gigatonnes per year.”

      (NASA Global Climate Change, “Vital Signs of the Planet: Land Ice”)

      • Doordenker

        How do we know for sure humans are (sole) responsable for this rise and not some natural cycle, vulcanic eruptions, etc?
        Were there no times in history that CO2 levels were as high or even higher than current 407PPM?

        • CB

          “Were there no times in history that CO2 levels were as high or even higher than current 407PPM?”

          Of course there were!

          Were there polar ice sheets at the time?

          “Around 52 million years ago, the concentration of the greenhouse gas carbon dioxide (CO₂) in the atmosphere was more than twice as high as today… In an area where the Antarctic ice sheet borders the Southern Ocean today, frost-sensitive and warmth-loving plants such as palms and the ancestors of today’s baobab trees flourished 52 million years ago.”

          (Science Daily, “Tropical climate in the Antarctic: Palm trees once thrived on today’s icy coasts 52 million years ago”, August 1, 2012, Senckenberg Research Institute and Natural History Museum)

        • Coert Welman

          You may be interested in my response to CB below.

  • PeterC

    Only ONE simple question is needed to respond to the AGW faithful:
    Does anyone KNOW if carbon dioxide is able to cause any changes to climate?

    • Geoff Offermann

      Sure. Satellites have recorded the drop in IR escaping to space.

      • PeterC

        Satellite IR measurements are in error: the size of CO2 IR is determined by the height of the measuring satellite. (Search for pjcarson2015, chapter 1A. It’s quantitative, and also shown by Venus’ & Mars’.) The higher the satellite, the greater the apparent drop in CO2’s IR. Embarrassing for NASA, etc, isn’t it?

        • Geoff Offermann

          LOL…touting you’re own blog as peer reviewed work, eh? Embarrassing for sure.

          • PeterC

            Who said my site was peer reviewed? (There’s a lot of peer review rubbish out there.)
            Are you capable of thinking for yourself?

          • PeterC

            By their nature, blogs are not peer-reviewed – except by the readers, which is probably more extensive. I invite you to do so there.

            • Geoff O’Furman

              You seem to think your analysis is significant. Don’t hide you lamp under a bushel. Peer review is essential to ensure your viewpoint is free of pitfalls like bias. Just as Wallace sent his manuscript to the leading authority on evolution of his day, Darwin, perhaps you should run it by some climatologists to give it a look see. Perhaps aNobel is in the offing. Or perhaps a position at Heartland.

  • MacUndecided

    This is a very simpleminded set of arguments and explains why the liberal mindset is perceived as being worshipful of science without actually understanding science. Lets look at them individually.

    1. Is climate changing? Yes. Nobody disagrees with that statement, not even the most ardent (but qualified) climate change skeptics.

    2. Do people have something to do with climate changing? Yes. Again nobody disagrees with that statement. Even a single person emitting a single fart affects the climate. That one person with their one fart has an extremely small effect but the effect is non zero. There is no argument with the absolute statement. The debate is not whether humans are affecting the climate, but by how much relative to other factors. The argument here is misleading.

    3. Is climate change bad? Now we get to absolute value judgements. To say that climate change is bad is to say that change is bad. Let’s look at a little archeological history. We know that the human species evolved in a time when there were rapid fluctuations in climate. Also climate has been changing since the day the earth began. Climate change is the norm not the exception. To resist climate change is to resist the natural order. Try harder chicken little this argument is unconvincing. Good / Bad are simply value judgements and they have no merit in any debate that calls itself scientific.

    4. Can we do anything about it? Yes, we can. But the cost of doing something about it is large and the impact is small. If we invested 100 billion dollars in fighting climate change (using the strategies proposed by the liberal community) we could reduce the rise in global temperatures by 0.01 degree at best. The earth has been fluctuating over a global average deviation of +/- 10 degrees for millennia. In fact the warmer periods of earths history are correlated with increased biological diversity, whereas cooler periods are correlated with decreased biological diversity. It is commonly accepted that ecosystems are more robust when they exhibit more biological diversity. So yes we can do something about it but the real question is should we and that is highly debatable.

    5. Is it worth doing anything about? Depends on your perspective. When you get past the superstitious sensationalism Ala. Al Gore where the planet melts down and everything dies because the global mean temperature rises a few degrees, and you look at actual impacts then the question becomes what should we do, and what doesn’t make any sense to do.

  • Frank Humphries

    First, we have to understand what climate deniers are being fed by the right news source and overcome those objections. For example, it is impossible that the temperatures are on the rise because there are places experiencing unusually cold weather, weather patterns have always changed through time (ice age), scientists just need something to justify their grants, scientists have been wrong in the past, and there are those who may believe in anthropogenic climate change but believe it is too late because they saw a video about climate change called Adam ruins everything….. start out by telling them “you ever wonder why it is even hotter in car on a hot day with windows rolled up?…. you know the rest….. Secondly, appeal to their emotions. ask them what patriotism mean to them ? ask them what is a patriot? compare how a governmental soldier fights to protect us that is exactly governmental scientists are doing -they are fighting to protect our future food securities and……… lastly ask, what are the motives of scientists ? what are the motives of oil companies and lobbyists.

    • MacUndecided

      First you have to understand science. Next you need to understand what climate change skeptics are actually saying. Third you need to let go your simpleminded straw man arguments and be prepared to dive deep into real science. Liberal worship of science without actual understanding of science is why liberal credibility suffers.

      • Frank Humphries

        I am not sure what you are actually saying but I am a scientist (certified archaeologist with a masters in environmental science) The problem with scientists is that they often talk among themselves in peer reviewed scientific articles. The non-scientists do not have the time to read peer reviewed articles and they can be difficult to understand. I do think climate science needs to be simplified for the layman while simultaneously overcoming their objections (what climate skeptics are saying). Perhaps you misunderstood my post or I misunderstood your reply but in any case thank you for replying.
        You know what would be helpful is a Liberal Cowboy type to run for president. Some one that has old school values, drives an old truck that runs on bio-fuels, looks like Paul Newman in HUD, listens to country music except for Toby Keith, is against factory farming, pushes for clean energy and protection of our environment for future generations…. He would appeal to the American traditions of voters… He would let the voters know he is patriotic and that is why he wants to protect the future food securities of America by way of protecting the environment and protect our traditions at the source of where we extract our identity from the “wilderness” (environment), while not sacrificing the economy by making more clean energy jobs. Germany has 80% of their day energy from renewable clean energy sources.

        • MacUndecided

          So you think that you are an expert in climatology or atmospheric science because you have a masters in environmental science, possibly from a degree mill. Well sorry to bust your bubble but the public is not entirely as ill informed as you seem to think. Why doesn’t it bother you that the climate alarmists seldom display data showing Co2 AND temperature on the same graph? It isn’t hard to do. Except when you look at the data it becomes evident even to a lay person that while over the last 150 years or so, temperature and CO2 are both rising they do not seem to rise at consistent rates. To display the data in the way I described betrays the narrative. This is one of many issues I have with the narrative you seem to have bought in to. But if you really ARE a scientist then assert and defend … unless of course you do not feel competent to defend your position. There are other issues with the way data is collected, stitched together and massaged too. But I am familiar with environmental scientists and they typically don’t actually do science, they typically work for some environmental agency deciding whether people can build decks in their back yard, or whether or not to approve / disapprove some real estate development. Departments of ecology are populated with bureaucrats not scientists.

        • MacUndecided

          Non scientists DO have time to read peer reviewed articles, and can understand them if they are willing to invest the effort. But from what I have seen the attempts by the AGW proponents to communicate with broader audiences tend to oversimplify the studies to the point of being disingenuous.

          Peer review is only valuable in an environment of healthy dissent. Due to the political pressure being placed on scientists operating in this domain, dissent is squelched and under these circumstances peer review only leads to group think that conforms to the approved narrative.

          Your comment on Germany betrays your own inability to think for yourself. As it turns out Germany is not nearly as green as the PR narrative would lead us to believe.

  • I have found the best single tool to open a discussion with a climate denier is to show him or her a graph of the Keeling curve – the steadily increasing measurements of CO2 in our atmosphere as measured on Mauna Loa in Hawaii

    • MacUndecided

      You do realize that those measurements did not start until the 1950s, don’t you? Mixing and matching measurements from different measurement systems is exactly the kind of data manipulation that climate change non-alarmists find so frustrating coming from the climate change alarmists.

  • Milo

    I go with melting glaciers, melting ice-caps; increased temperatures, all caused by increased levels of CO2 as a result of burning of fossil fuels since the Industrial Revolution. The difference now with climate change, is that 7 billion people rely on predictable and consistent weather for farming to feed that population.

    • MacUndecided

      So is it your position that all of the climate change that has happened in the last 200 years is a consequence of CO2 from man’s burning of fossil fuels?

  • Oil addiction fuels brain damage and a raft of other earth-shattering consequences. Anyone willing to debate people suffering a substance abuse problem and living in silos of denial, fear, uncertainty and doubt doesn’t understand the disease. Imho.

    • MacUndecided

      Funding addiction fuels corrupt science, and the liberal agenda of getting something for nothing.

  • JRW40113

    All built on the premise that AGW is real and the “cause”. AGW is a hoax and man is not the cause of climate change.

    • Hogrider16

      I think your tin foil hat is leaking.

      • JRW40113

        Typical progressive alinskyite, don’t respond to my statement, name call and belittle to try and make yourself seem somehow superior. Run home and drink your progressive koolaid and tell yourself you are so smart like a good little boy.

  • disqus_y2rfjHWjYV

    This post is still absent of fact.

  • JimFogleman

    Has there ever been a time when the climate didn’t change?
    What is the ‘correct’ temperature of the planet?
    If you drop an ice cube in the Pacific Ocean, the temperature of the ocean has to drop. How much is the question?
    Was the earth a ‘nicer’ place during the ice ages? If not, was climate change bad?
    How far do you have to carry a sign & march, to reduce the earth’s temp?
    Will wild claims of people like Al Gore every be examined?

    • Hogrider16

      They have been, but flat-earth d’bags like you refuse to acknowledge facts.

  • Brad

    I’d like to make a few additional points beyond the ones brought up so far in the comments:

    1. The argument that a majority of climate scientists believe xyz generally falls flat with skeptics, because the history of science has shown that consensus views can turn out to be wrong; one person who is right is worth 10,000 who are wrong. Conservatives in general also have a tendency to sympathize with “rugged individualists,” the ones who won’t run with the pack and hold views contrary to the mainstream. From a purely scientific perspective it doesn’t matter how many people support a “consensus” view, but from a policy and decision-making perspective it’s difficult to make a logical argument for ignoring a majority view in favor of a more convenient minority opinion.

    2. The point about trusted messengers is a good one. If you want to change public opinion in a certain segment of society, it’s probably worth trying to focus on changing the opinions of that segment’s trusted messengers. Not easy to do, but it’s probably the only approach that could actually change things.

    3. Read “The Righteous Mind,” by Jonathan Haidt, or visit his website and watch the interviews if you don’t have time to read the book. It provides a lot of insights into the underlying values, mindsets, and motivations of conservatives, who for a variety of reasons have a higher tendency than liberals or nonpartisans to be skeptical of climate change and prone to conspiracy theories. Reading it should also help stop people from demonizing those who disagree with their views. It’s worth trying to understand the people who disagree with you so you can appreciate why they think the way they do. It may not do anything to change their minds, but it can lead to more civil and hopefully productive discourse.

  • PeterC

    Simply stating, as in #2, that people have something to do with changing climate does not make it so.

    As for greenhouse gases, ALL gases in the atmosphere are greenhouse gases as they all absorb heat one way or another. Therefore, CO2, as a very minor component (as is methane), has a very minor effect upon climate changes.

    • Geoff Offermann

      The evidence makes it so. We know the carbon increase in the atmosphere is paleo from isotopic analysis.

      • MacUndecided

        Your oldest readings on CO2 come from Ice cores. When you look at Ice core data it shows very steady readings over time. But a more accurate but less far reaching (back in time) method of assessing past levels of CO2 is to look at plant sotmata. When you overlay measurements within the same time period between plant stomata readings and ice core readings you find 2 things. 1) Plant stomata readings tend to read higher than Ice core readings, 2) Plant stomata readings tend to fluctuate much more than the corresponding Ice core readings.

        One theory on why this is suggests that some of the Co2 in the entrapped bubbles in the Ice cores diffuses out of the bubble into the ice itself. If this is the case then stitching the two data sets together will enable you to produce misleading results. So if you want to talk about rates of change in the system one thing that must be held constant is the method of measurement. One of the biggest flaws I see is the use of multiple measurement techniques and the tendency to stitch the data from these apples and oranges together to present a misleading conclusion.

      • PeterC

        Yes, Man is the cause of the increase in CO2 levels over the past century, BUT nobody has yet shown that CO2 is able to cause any climate change …. Because they can’t as it can be shown very easily from the properties of gas mixtures that CO2’s total effect on global warming is a bit less than its concentration in the atmosphere, ie ca 0.04%. (This is 1st year uni chemistry.

        • Geoff Offermann

          I won’t bother disputing your claim regarding CO2’s effect as it’s not entirely relevant. Furthermore, even the slight increase you admit is, after all, an increase. But why are you so focused on just CO2? It is hardly the only atmospheric carbon nor is carbon the sole cause of greenhouse effects.

          • PeterC

            Because CO2 is the focus of AGW.
            (Anyway, the other IR gases are even smaller concentration and therefore smaller effect.)
            A tiny increase of say 0.04 to 0.05 is zero effect on global temperature, within experimental limits.

            • Geoff O’Furman

              Nonsense. CO2 is just one GHG. And again, you state increases which are increa

              • PeterC

                Must be some sort of feedback! Orders of magnitude greater than the initiating cause! Hasn’t happened in past times either. Can you name such a feedback?

                AGW likes to invoke such difficulties because it can’t match real data. It invokes mysticism instead!
                I prefer to take the easy way and rely on quantitative calculations from known properties. Seems to work.

                [To put you out of your misery, Global Warming over the past century matches the heat released at (largely undersea) tectonic boundaries (Chapter 2), which has been measured to be increasing since 1900 where this analysis was started, in a very similar fashion to GW – in fact more accurately and for longer than CO2 does.]

                • Geoff O’Furman

                  Yep…that’s how feedback work. Surely you’ve heard of the gigatonnes of methane being released from tundra or the decline in arctic albedo. Those are huge feedbacks and are adding tremendously to the amount of heat absorbed by the Earth.

                • PeterC

                  Then why is feedback only now, over the past 60 years or so, being invoked? CO2 has been rising for hundreds of years – or regularly up and down over the past 420,000 years – with no such feedback.

                  If gigatonnes of CH4 have been released, and CH4 is 25X (you pick a number) more greenhouse than CO2, then why haven’t we experienced a pickup in warming? …. Because their effect is proportional to their concentration – tiny!

                  Just compare actual climate with what models predicted – there’s plenty to choose from.

                • Geoff O’Furman

                  The reason why it is only starting to happen relatively recently in significant quantities is because the tundra is going through longer and longer periods above freezing.

                  A “tiny effect” as you call them can become large. A small leak in the largest ocean liner will sink the ship given enough time.

  • Afroz Ahmad Shah

    Dear author,
    As a researcher I feel compelled to say that somehow we are still not sure how to compare the present atmospheric composition with that of early earth (e.g. Hadean and Archean). So I feel the question is not just about denial it is more about how we put things together in perspective. The public needs numbers and we ought to show them.
    No doubt a larger number of serious scientific works have established that increasing levels of atmospheric carbon dioxide gas over the decades have caused increase in temperature, and how much is that variation (~2°). And I think we all agree that early earth had much higher concentration of carbon-dioxide, and how we got where we are now is still vigorously debated, as evidence are settle. Plus the fact that carbon-dioxide is not the only driver of climate, and if we discuss its role, then obvious questions will be asked. This becomes obvious when we look at the composition of the air that we breathe. It mainly contains nitrogen (~76%) and oxygen (~21%). The concentration of carbon dioxide is just ~0.038% and the first two major gases in our atmosphere are NOT greenhouse gases, which means that there concentration has probably little to no effect on warming of the atmosphere. And the role of Sun, which is central to the existence of life on the earth as it provides heat that is required to keep the temperature and atmospheric circulation in balance. So the small amount of greenhouse gases (mainly water vapor, and little of CO2) traps (absorb and re-emit) the infrared radiation, increasing the temperature of the atmosphere. Again we need to look how concentrations of water vapor (the major greenhouse gap in our atmosphere) have changed over the geological time, and compare it with Holocene, that may give us some idea how it plays a role. Similarly we have to map the variations of clouds, the condensed form of water vapor, over the centuries or more to accurately map and understand the role in atmospheric composition, temperature etc. And we know that volcanic eruptions contrinute about 1% to the total CO2 budget, and thus this needs to be shown to the public. Apart from this there are also small percentage of naturally occurring other greenhouse gases in the atmosphere, which includes methane and nitrous oxide. And humans has also contributed some new varieties of synthetic greenhouse gases, which include chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs) and Perfluorocarbons (PFCs), as well as sulfur hexafluoride (SF6). These gases have also influenced the temperature structure of our atmosphere over the decades of industrial revolution on the planet.
    So I think here we are: the present concentrations of gases in our atmosphere are both natural and man-made. The contribution of each gas in modifying the concentration of greenhouses gases in our atmosphere is still vigorously debated, and most of the scientists agree that anthropogenic CO2 is the major contributor, but we are yet to solve the problem over the geological timescale. However, humans ought to be responsible not to aggravate the obvious problems that we are facing right now, and must workout solution for a better future. Please remember that Earth is a delicate system of systems, and we are part of it, any of our wrong actions can alter its delicate balance, which will ultimately destroy life, including us.

  • Ronal Larson

    How about an approach that is questioning – why should we allow China to take the present US climate lead? (as they have for all the renewables). This seems different than introducing a scare – which we are advised is not effective.

    • 9.8m/ss

      Questioning can not challenge a deeply held belief system. Whether there’s any evidence for that belief system is irrelevant. The person who lives in the Fox-Brietbart alternative universe has answers to all your questions. The Chinese are lying about their advances in renewable energy. They’re secretly building nine new multi gigawatt coal plants each week, and only pretending to retire the old ones, because they know AGW is a hoax and coal is the future! The solar panels they sell us are sabotaged and will wear out in three years. But, more centrally, the belief system is immunized against any facts which contradict it. They’re all inventions of the liberal conspiracy to destroy America!

      Recently I’ve been seeing advertisements for residential PV systems which seem to acknowledge the problem the Fox-Brietbart mythology presents. They imply that the power company is part of the government and the liberal conspiracy, and you can stick it to the man by getting off the grid. They carefully avoid mentioning the environmental benefits of converting to solar energy.

      • MacUndecided

        You know it is interesting that AGW proponents are afraid to debate climate change skeptics but you never see scientists afraid to debate creationists, or flat earthers. I suppose this is because on the topic of evolution or the round earth theory scientists are on solid ground, but on climate change they are on shaky ground and do not want to see their reputations destroyed by having their professional opinions dismantled piece by piece.

    • MacUndecided

      The basic premise of climate change alarmism is very questionable to me having looked at all of the information I can. The CO2 alarmists in focusing all of their attention on a very short span of time, geologically speaking, have undermined their own credibility. If you start measuring temperature in December and behave as though December is the beginning of time, then by April as things start to warm up you will be very alarmed indeed. But if you measure temperatures over the span of a few years, then the spring thaw is less alarming. All of the IPCC focus is based on Ice core data and modern metrology which spans a very short, and relatively very cold period of earths history. Much of the alarm in my mind comes from the fact that they are treating this short period of time as though it were ALL of time.

  • Andrew Chermak

    A good article. It might be helpful to mention some of the sources of natural variation in greenhouse gases over geologic time and cite some specific numerical examples of what we know about temperature and precipitation variations that resulted from those natural inputs and how they compare with recent anthropogenic shock inputs. Even relatively non-scientific people can understand the numbers.

    One observation might be better not stated, or at least stated differently, the part that says “………No amount of factual education can alter this worldview, and it has become clear that other means must be found to prevent this segment of the population from making self-harming decisions, whether induced by disinformation or otherwise.”. We all get frustrated by people who simply refuse to see things our way but the implications of “other means must be found” are truly frightening to contemplate.

    • Thomas H Pritchett

      I have made it a point to be active on social media such as Facebook and to have as wide of group of friends in terms of political beliefs. Therefore, I have friended not only colleagues and others who share my views on climate but also high school classmates and people I have encountered in hobby, Civil War Reenacting. I have made it a point to never remove anyone from my Friends list because of their political views and have tried to only engage them respectfully in disagreements. Another thing, I find that most scientists tend to avoid interacting with local groups who are working to make changes in the political will for dealing with climate change. I know that we are all busy but there are groups out there who could use our expertise. Personally, I have become active in the Citizen’s Climate Lobby but there are others of a similar nature out there. Furthermore, I would suggest that we could become more active in engaging the public with well thought out Op-Eds and Letters to the Editors at our local newspapers.

  • philippe vidon

    The rationale behind this short article makes no sense whatsoever. Is AGU and most of its scientists so narrow minded that they still believe that facts will lead people to change their mind? Human beings are irrational by nature and emotional. Further, simplifying climate change like it is done in the article above, and speaking in terms of absolute truth is the first mistake in this article. Currently, the rhetoric around the concept of climate change has become so simplified that it is basically wrong. I agree that the burning of fossil fuels is causing warming, but considering that we can probably all agree that we still poorly understand climate (e.g. el Niño), bringing it down to just controlling emissions is really a problem. We know from recent research that people’s worldviews have more impact on the perception of climate change than any data a scientist can publish. As long as AGU keeps pushing for an overly simplistic view of climate change and ignores how people develop opinions, we won’t go very far in convincing the world that climate change is a problem.

  • tolo4zero

    If anyone questions anything at all about the Catastrophic Anthropogenic Global Warming scare, they are considered climate change deniers.
    This is not science but a religion.

    • drklassen

      Yes, climate change denial is religion, not science.

      • Dick Rasmussen

        Those are all good reasons ! — But I very much doubt you are going to convince people with this type of article even as true as it is. I look at climate warming simply by the industrial revolution 1850 to the present along with the population growth in that time and the development of all the countries in the world in that time. To me it is simple logic that it couldn’t be anything else.
        If folks don’t want to accept that there are not any magic words that will convince them. But I’ll keep trying !

    • 9.8m/ss

      What makes you think so? Most areas of science are too competitive for a scientific religion contrary to evidence to survive. How is that competition suppressed in the climate related sciences? Who’s organizing the suppression? Why are they doing it?

      • MacUndecided

        Simple, because the debate is not being controlled by scientists, but by politicians. Even scientists are corruptible. If given the choice to massage the numbers you control in order to create a narrative that gets you funding and recognition, versus the choice to be analytic, factual and a bit skeptical, which gets you labeled with all sorts of negative labels, and a loss of funding most people in the scientific community go with the side of bread having the most butter e.g. they go with the narrative rather than cold hard facts. One need only take a careful look at the way that the IPCC manipulates data in their own reports to draw wild conclusions that do not stand up to scrutiny to see the effect of politicized “science” at work.

      • MacUndecided

        Most areas of science ARE too competitive. But THIS particular area has become highly politicized. Competition implies dissent, and criticality. Anyone who questions the existing conclusions is not met with data defending the conclusions but instead is met with ridicule and scorn. Furthermore funding plays a critical role. There is a great deal of money available to scientists who claim that climate change is a serious problem. Scientists who claim otherwise will naturally not get such funding because who funds research on non-problems?

        • 9.8m/ss

          “There is a great deal of money available to scientists who claim that climate change is a serious problem. ”
          There is even more money available to scientists who claim that it’s not. The fossil fuel investors’ public relations operation pays long-retired former scientists several times the typical climate researcher’s salary of about $60K/year. Unfortunately for these celebrity retirees, they haven’t been able to bust any of the theories that inform the consensus. There’s quite a lot of evidence for the consensus theories, and not much for the dissenters. The one who does is a cinch for the next Nobel Prize in physics. That it hasn’t happened yet is the most powerful argument that the consensus is correct. You are simply mistaken about the lack of funding for dissenters. John Christy and Roy Spencer get their NSF grant every year despite the poor quality of their work.

    • MacUndecided

      Climate change alarmism is religion. Climate change skepticism is actually scientific.

  • Spencer Weart

    Unfortunately, stating true facts is useless unless your audience believes that you are a credible source of information. Your audience has probably heard the exact opposite statements (humans are not responsible, mitigation is too costly, etc.) from sources they may trust more — certain politicians, Fox News, the Wall St. Journal, etc. Thus the essential first step is to establish your credibility. Just being a scientist does not automatically make you credible; it may even make you suspicious. So you need to show that you understand and sympathize with your audience’s world-view, that you are describing a near-universal consensus of genuine experts, etc. (It may also help to undercut the credibility of our opponents by emphasizing their financial and ideological interests in denial.)

    • David Huard

      I would argue strongly against attacking your opponent’s credibility in a debate. I find the best way to establish credibility is not to emphasize your scientific credentials, but to behave like a nice, reasonable and empathic person. Accusing someone of having undisclosed, vested interests is perceived as mean by a neutral public and undercuts your own credibility. I find it much more effective to discuss the cognitive biases that we all have, and how to avoid being tricked by them. In other words, make these discussions about “How to think like a scientist”, and let people reach their own conclusions.

      • Spencer Weart

        That sounds right. I certainly wouldn’t attack another individual directly, but in speaking generally I think the work by Oreskes et al. exposing the financial links of deniers can be useful.

        • David Huard

          Agreed. I also like to use concepts from “Scientific Certainty Argumentation Methods (SCAMs): Science and the Politics of Doubt” by Freudenburg at al. to discuss these issues.

        • Paul Ruscher

          This has been helpful apparently in places where carbon disinvestment discussions have taken place. I try to be respectful and factual always and don’t like using denialist and alarmist labels

    • DHClark

      I agree that establishing your credibility is crucial to getting people who are on the fence (or even more so, those who are antagonistic towards climate science) to listen. One of the more effective tools I’ve used in public discussions is to diffuse the notion that climate scientists are basically being “bought off” in seeking funding (i.e., we’re just toeing the line on climate change to get grants or pubs). I use a few lines of reasoning: 1) active scientists are, by nature, a contentious bunch and that we get funding (and whatever fame is possible) not by toeing the status quo, but by showing that the status quo is wrong. We’d all LOVE to be the one to show AGW is wrong, but rigorous studies repeatedly reinforce the basic principles in the IPCC. 2) I dispel the notion of being in it for the money by walking through the breakdown of an NSF climate change grant I received recently (ice coring); the total amount looks really big (100’s of thousands), but only part of that comes to my university (rest to other PI’s); of the part coming to my university (still a lot), most is for subcontractors (helicopters, equipment, field expenses etc.) and indirect costs. It’s also spread over 4 years Of the remainder, most of the salary goes to grad student RA’s and analyses. Boiling it down to any funds I would actually see as salary, it amounts to a few thousand a year. I ask the audience how many of them would go against their core beliefs for that small amount. Most folks have no idea that research grants work that way…they have a sense that the PI’s just get a big check and can go do what they want with it. It really is a surprise that such a big grant amounts to so little in my own bank account.

      • Ben

        Engaging with the public in this way is sorely lacking. I find it is not supported very well by scientific institutions in reality. I get pressure from my seniors to deliver research and publish but very little encouragement to communicate with the public. And if I can get out to communicate, being in California, I am simply “preaching to the converted”.

        The real challenge is mobilising science in areas that are more traditional or isolated, and on a scale that will have real impact. I think the challenge is enormous, not least because of the points raised in the original article. Many people are so tied to their (mis-informed) views, and perhaps scared of the reality and having to actually do something, or sacrifice something, that *any* approach based upon logical argument (like establishing the credibility of your source) is futile. It is equivalent to shouting at the television.

        I have been talking with friends and colleagues about how to approach this problem. I don’t have any immediate answers, but I have some ideas about putting more of a human face on the voice of science – a very large project involving hundreds or even thousands of international scientists being seen and heard in an emotional (or at least more human) way, might have an impact. (As opposed to publications, offical reports, IPCC, the occasional letter to congress etc).

        I think until there is a focus on more aggressive outreach in places that matter, and on a scale that makes a difference, we are fighting a losing battle.

        • Thomas H Pritchett

          See my reply to Andrew Chermak in terms of how to mobilize science. However, I agree with your last sentence that we are currently fighting a losing battle. However, I believe it is not because the fight is unwinnable but because we are allowing the other side to dictate how the battle is to be fought and they are taking advantage of our seeming unwillingness to come out our academic shells and directly engage the public via social media and other non-academic venues. In fact, I would suspect that many of us may subconsciously look down out our colleagues who do. We all know that Dr. Hansen has become a very public advocate towards addressing climate change but I wonder how many of us feel that he may have cheapened himself as a scientists for acting in this manner; I know that I have had to fight that impulse when I saw his name on his most recent publication. Furthermore, I suspect that I am not the only one here who may have had brief, but totally unjustified, thoughts along this line.

          • MacUndecided

            Why don’t you try engaging the public as equals rather than as aloof ivory tower dwellers who feel that people outside your community are beneath you. If you can’t explain yourself to the uninformed then you really don’t understand what you are explaining OR what you are trying to explain is wrong.

            • Thomas H Pritchett

              And what makes you think that I do not try engaging them as equals? Yes, I am a Chemistry professor so my knowledge of the science is likely to be more sound than theirs but, if you look at my profile picture, I do not automatically project the image of an aloof ivory tower dweller. My talk about coming out of our academic shells was more a challenge to my colleagues as I am already engaging the public via various outreach means. The problem is that in academia such outreach is often not considered to be “scholarly endeavors” when it comes to the various peer and promotion evaluations.

      • 9.8m/ss

        When I told my scientist friends what I heard on Fox and read on Breitbart about how climate scientists are compelled to lie for funding, they burst out laughing. It’s a conspiracy story as preposterous as the one where Richard Cheney wired the WTC towers with explosives. But try telling a Fox-Breitbart adherent how competition and pre-pub review really work, and they’ll tell you straight out that you’re lying and you’re a fool for letting the liberal media dupe you like that. The explanation of how scientists are motivated in the real world is facts and reason. Facts and reason can not usurp a tenet of a comprehensive mythology rooted in fear and resentment. I’m afraid the folks who are surprised at how grants work are the folks who are already receptive. The Fox-Breitbart adherents are not surprised at the idea that research grants work that way, they’ve already been taught that competition for correctness and novelty is suppressed in the climate related sciences by the liberal conspiracy. Anyone who tells them it’s still active is carrying water for the alarmist cabal.

  • Saskia van Manen

    I think you make an interesting point here, about needing to connect with audiences on a more emotional level. However, by subsequently providing facts to communicate, I think you make an even stronger point for leaving the communication of scientific findings to professional communicators, rather than to scientists themselves.

    • MacUndecided

      What problem are you trying to solve? Science is not about propaganda so trying to use propaganda (and emotional appeals are a form of propaganda) to convince people to agree with you is only going to demolish the integrity of the scientific community. It took almost 200 years for science to gain enough credibility to enable people to treat scientists like a modern day priesthood. If you loose your integrity sooner or later you will lose your credibility and this would be a great loss. One thing is for certain right now scientists are far too certain about things.

  • John Boyd

    Couldn’t agree more, but in my small experience, the difficulty is in actually engaging with people beyond point one.

    • MacUndecided

      Engage with me. If you can’t convince me then you will never convince people who think that Jesus makes the rain come.

      • CB

        “If you can’t convince me then you will never convince people who think that Jesus makes the rain come.”

        The religious metaphor is appropriate.

        Only someone profoundly disinterested in reality would reject centuries of well-established scientific understanding without a shred of evidence…

        “The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-19th century”

        (NASA, “Climate change: How do we know?”)

  • Dan Zacharias

    While Dork Sahagian may disagree,

    1. Is the climate changing?
    Yes, there are many sources for data to indicate fluctuations in climate trends.

    2. Do people have anything to do with it?
    Yes, humans contribute to the change in climate. But contrary to claims otherwise, there is not a consensus that humans are the sole cause of climate change.

    3. Is climate change bad?
    No, while changes in climate will continue to impact human civilization as trends in climate change have since the beginning of human history. We, like our forebears will migrate and adapt. Modeling of precipitation patterns suggest increased atmospheric water vapor which in turn increases precipation contributing to erosion and other factors. These changes are projected to increase the carrying capacity of the Earth.

    4. Can we do anything about it?
    Yes, we can choose to increase our reliance on technology and thereby increase our power production which will inevitably increase greehouse gas emissions and warm the atmosphere. We can develop and test newer nuclear devices in the open air and sea. Furthermore, we can increase our commute times, eat more fiber and produce more methane. At it’s core, human behavior is where things need to change.

    5. Is it worth doing anything about?
    Yes, while the costs of adaption has by some accords been estimated to dwarf the cost of mitigating human contributions to warming trends, there are issues with the calculation of such cost projections. Humans will migrate to locations currently considered inhospitible due to the lack of resources primarily water. Post global climate change, annual precipitation is expected to increase, providing such resources to otherwise desolate geographic regions. The carrying capacity of the earth will increase, crops will not only thrive, but will be able to be grown year round.

    Sure there will be consequences such as endless mosquito seasons, more severe weather, and loss of property due to increased ocean levels. But, from my perspective, the pros outweigh the cons.

    We shall agree to disagree regarding the extent to which humans contribute to climate change. But to dismiss someone’s scientific based perspective because it’s contrary to an alleged consensus isn’t the way to convince someone. I’d venture to suggest that we would agree that further research upon the various disciplines of earth, environmental, meteorological, geophysics and other branches of science. Each person should study the research, ask questions, seek understanding, review the data, and formulate their own opinions.