CLIMATE CHANGE: Scientists have spent the last 150 years proving that human emissions of greenhouse gases have created global warming.
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This excerpt is from The Discovery of Global Warming, by Spencer R. Weart (Harvard University Press, 2008).
It is an epic story: the struggle of thousands of men and women over the course of a century for very high stakes. For some, the work required actual physical courage, a risk to life and limb in icy wastes or on the high seas. The rest needed more subtle forms of courage. They gambled decades of arduous effort on the chance of a useful discovery, and staked their reputations on what they claimed to have found. Even as they stretched their minds to the limit on intellectual problems that often proved insoluble, their attention was diverted into grueling administrative struggles to win minimal support for the great work. A few took the battle into the public arena, often getting more blame than praise; most labored to the end of their lives in obscurity. In the end they did win their goal, which was simply knowledge.
People had long suspected that human activity could change the local climate. For example, ancient Greeks and 19th-century Americans debated how cutting down forests might bring more rainfall to a region, or perhaps less. But there were larger shifts of climate that happened all by themselves. The discovery of ice ages in the distant past proved that climate could change radically over the entire globe, which seemed vastly beyond anything mere humans could provoke. Then what did cause global climate change — was it variations in the heat of the Sun? Volcanoes erupting clouds of smoke? The raising and lowering of mountain ranges, which diverted wind patterns and ocean currents? Or could it be changes in the composition of the air itself?
In 1896 the Swedish scientist Svante Arrhenius published a new idea. As humanity burned fossil fuels such as coal, which added carbon dioxide gas to the Earth’s atmosphere, we would raise the planet’s average temperature. This “greenhouse effect” was only one of many speculations about climate change, however, and not the most plausible. Scientists found technical reasons to argue that our emissions could not change the climate. Indeed most thought it was obvious that puny humanity could never affect the vast climate cycles, which were governed by a benign “balance of nature.” In any case major change seemed impossible except over tens of thousands of years.
In the 1930s, people realized that the United States and North Atlantic region had warmed significantly during the previous half‑century. Scientists supposed this was just a phase of some mild natural cycle, with unknown causes. Only one lone voice, the amateur G. S. Callendar, insisted that greenhouse warming was on the way. Whatever the cause of warming, everyone thought that if it happened to continue for the next few centuries, so much the better.
In the 1950s, Callendar’s claims provoked a few scientists to look into the question with improved techniques and calculations. What made that possible was a sharp increase of government funding, especially from military agencies with Cold War concerns about the weather and the seas. The new studies showed that, contrary to earlier crude estimates, carbon dioxide could indeed build up in the atmosphere and should bring warming. Painstaking measurements by C. D. Keeling drove home the point in 1960, showing that the level of the gas was in fact rising, year by year.
Over the next decade a few scientists devised simple mathematical models of the climate, and turned up feedbacks that could make the system surprisingly variable. Others figured out ingenious ways to retrieve past temperatures by studying ancient pollens and fossil shells. It appeared that grave climate change could happen, and in the past had happened, within as little as a few centuries. This finding was reinforced by computer models of the general circulation of the atmosphere, the fruit of a long effort to learn how to predict (and perhaps even deliberately change) the weather. Calculations made in the late 1960s suggested that average temperatures would rise a few degrees within the next century. But the next century seemed far off, and the models were preliminary. Groups of scientists that reviewed the calculations found them plausible but saw no need for any policy action, aside from putting more effort into research to find out for sure what was happening.
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34 Comments
Add CommentThere aren't greater blind than who don't want see.
Reply | Report Abuse | Link to thisThis is only a politician coment and only a opinnion, but weather don't matter ours opinnions, it will change also.
Great paper. I only think one thing about it.
Reply | Report Abuse | Link to thisThe extreme weather that is doing the last decades indicates that climate change must began. But mundial leaders only talk about how much carbon can burn and they don't do nothing to warn the consequences of change.
I think that the change will fall over ours with a bomb and we will not be ready
Ah, the dreaded "blah blah blah" rebuttal. Merciless.
Reply | Report Abuse | Link to thisThank you, Shoshin, for that evidence-free rant. Enlightening.
Reply | Report Abuse | Link to thisWhat does "blah blah blah" look like? Picture a schoolchild with fingers in his ears, humming.
Reply | Report Abuse | Link to this>Ah, the dreaded "blah blah blah" rebuttal. Merciless.|
Reply | Report Abuse | Link to thisLOL!
We human are the architectonic and producers of climate change by our inconsiderable plan use of energy....
Reply | Report Abuse | Link to thisI am convinced that much of the global warming is at least partially an affect of human activity. I am totally convinced that whatever the cause is, humankind is exacerbating the problem because of our dying need to pollute the earth, water, and sky.
Reply | Report Abuse | Link to thisEven if you are not convinced that global warming is happening or that it is brought on by humans, can you still think that polluting our planet is a good idea?
Can someone help?
Reply | Report Abuse | Link to thisI know about the greenhouse effect. Good thing to have to be able to survive. Also lots is being said about the increase in temperature when the "greenhouse gases" concentration increases because more infrared energy is reflected back to the ground.
BUT, if more is reflected back to the ground, why is not more reflected back away from us when it is coming from the sun? and what is the net difference? Are we conveniently forgetting about that?
@Lumberjack,
Reply | Report Abuse | Link to this>BUT, if more is reflected back to the ground, why is not more reflected back away from us when it is coming from the sun?|
Stefan–Boltzmann law
http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law
Black-body Radiation:
http://en.wikipedia.org/wiki/Black_body
>Are we conveniently forgetting about that?|
Please stop conflating your ignorance with the state of scientific knowledge.
Amazing how that exact quote was in another published post and I remarked on it then. Sorry, the basic physics of human caused global warming by CO2 has not been understood for 150 years. Love the historical rewriting. The 1930s? really? Everyone was still using rivers for raw sewage back then and dumping slag directly into lakes to "dispose" of it and these same people who justified that insanity somehow understood global warming back then? With what data? The current global warming caused by human fantasy is based on statistical modeling from elaborate and powerful computers using ice core and other data that could not possibly have been known in the 1930s or earlier.
Reply | Report Abuse | Link to thisAt best they had a few guys totally speculating on what if scenarios.
And how is global warming discovered? Anyone who has been alive and aware since the late 1970s blizzards(that prompted claims of ice age cometh) knows it is warmer now.
Well I will repeat what I said in the last article about geoengineering the planet. The warmists have an incredible amount of arrogance to even suggest they know enough about the atmosphere to make claims like they understand the basic physics of the atmosphere. They cant even explain warming today with fact. It is all theory, may haves, could bes, might be this. Their claim of CO2 as the cause doesnt even test out in a lab. Until only this year did the interaction of clouds and the atmosphere become better understood. Mention the fact we take temperature of only near the surface, I am told the rest of the atmosphere doesnt matter.
You warmists do not in fact understand how the atmosphere works, you have at best a partial understanding of the lowest part of it over land. You people certainly have not understood the atmosphere to even that limited detail for the last 150 years.
The only factual party of this article is the theories of local climate change caused by humans. Yes this was considered many times over history and unlike human caused global warming and its assumed constants and rigged data, local climate change can be measured with actual data and science, no computer models needed.
Amazing how you warmists take a small amount of fact real science and mix it in with your junk science to try and make it seem real. You people realize that it is local solutions that will solve your warming problem because each local area contributing to warming will be doing it in a different way. But then, you warmists are not really interested in solutions, you just want to have excuses to impose your taxes and regulations.
@ Trent1492 - Why do you have to be so pedantic and condescending, Lumberjack just asked a simple question? And your response is irrelevant to the question that was asked.
Reply | Report Abuse | Link to this@ lumberjack - The reason the IR isn't reflected back into space before it ever gets to earth is that it gets here as visible light, which gets absorbed by the earth, then emitted as IR. CO2 is transparent to light in the visible wavelengths, but absorbs certain IR wavelengths.
Mad Scientist Says: Lumberjack just asked a simple question?
Reply | Report Abuse | Link to thisTrent Says: No he did not. He asked an insinuating question. Perhaps you did not catch this part,"but, if more is reflected back to the ground, why is not more reflected back away from us when it is coming from the sun? and what is the net difference? Are we CONVENIENTLY FORGETTING about that?"
The "conveniently forgetting" phrase insinuates that geophysicists are either incompetent or being deceptive. He deserves all the contempt that he and others like him get.
>And your response is irrelevant to the question that was asked.|
Today I learned that Stefan-Boltzman and black body have nothing to do with an objects emissivity.
Re: "People had long suspected that human activity could change the local climate."
Reply | Report Abuse | Link to thisIs “local” climate the same as weather?
Re: "The basic physics of climate change have been known for more than a century, but it is in recent decades that the fundamental science of global warming has solidified"
If the information available to me is correct, Ted Turner has publicly stated his wish to have human population reduced by 90%. He also donated one billion dollars to the U.N. The grant funding for global warming/climate change research is provided largely by the U.N. Is there a connection? Is that a possible reason for solidification of gw science in recent decades?
Shorter Priddeseren: I choose not to believe the science historian's account because I do not want to believe.
Reply | Report Abuse | Link to thisWhatever it is that's what it is. The best anyone can ever do is appresheate whatever truth they can find. As of peoples assumptions; they simply define who they are by this. And in no wise define anyone else. Reality needs no ones approval for what it is. Although if human-kind is not willing or able to understand it(reality), it will do what it always does without concience: Not care what you or I think.
Reply | Report Abuse | Link to thislumberjack,
Reply | Report Abuse | Link to thisActually the greenhouse effect is that energy comes in as visible light (which passes through the atmosphere pretty easily, transferring some heat to the atmosphere) hits the ground, warms it up and is re-emitted as infrared light. The various greenhouse gases (water, CO2, methane, etc.) absorb the infrared much better than visible light and speed up (which is the same thing as heating up).
So the more greenhouse gases are in the atmosphere, the less infrared gets all the way through the atmosphere to be radiated to space.
That is the way global warming happens, basically. The heat balance changes to where more and more heat is retained by the planet as various mechanisms change how transparent the atmosphere is to infrared radiation.
P.S. I'm happy that mad scientist illiminated the insinuations rather than the next gie who splattered his ignorance everywhere with his loss of control and understanding. It makes no big difference to me either way. I don't know either one of them. I may never return to this web site - was just trying to fill my time for now.
Reply | Report Abuse | Link to this@Bill_Crofut
Reply | Report Abuse | Link to thisNo, there is no need to invoke conspiracies. There are multiple converging sources showing that climate change is a) real and observed to be happening now, b) a threat to human life and economy, c) due mainly to human activity.
It is very easy to find out what these multiple lines of evidence are. There are literally thousands of different temperature observations from multiple locations across the globe, observed changes in plant and animal life due to warming effects, as well as computer models with different levels of assumptions that explain current and past temperature anomalies.
To envision all of this to be fake, you have to postulate a massive conspiracy that is totally without flaw and has been so since 1930 involving thousands of researchers who illogically are involved in the conspiracy so that sometime some of them can get a small amount of research dollars. And most of whom are now publicly saying that the time for research is long over, and the time for political action has come and gone.
Or, you could envision a policy of sloppy disinformation by a much smaller group of businesses that have an economic stake in confusing people about settled science.
What do you think is the more likely scenario?
Lumberjack, have you forgotten that other planets (and the earth inclusive) surrounding our big star the SUN have their gravity and atmospheric conditioned to reflect back the solar rays activities to keep us-EARTH-balance?
Reply | Report Abuse | Link to thisSteveO,
Reply | Report Abuse | Link to thisRe: "No, there is no need to invoke conspiracies."
Please keep in mind, the first "conspiracy" is quoted from the text of this web page; the second "conspiracy" is a matter of public record:
Ted Turner donates $1 billion to 'U.N. causes'
http://edition.cnn.com/US/9709/18/turner.gift/
Ted Turner Wants Population Reduction Through China' s "One Child Policy"
http://www.youtube.com/watch?v=M7CP5jnXDUk
Re: "What do you think is the more likely scenario?"
Would cyclic variation be considered at least a remote probability? The idea is not originally mine:
IT WILL NOT BE THE END OF THE WORLD. AND IT IS NOT JUST about the polar bears on their lonely icebergs.
Those thoughts kept going through my head during our recent town hall meeting about climate change, which took place at Yale University this past January (see page 38). Popular coverage of global warming tends toward the broad and apocalyptic, or the narrow and remote. Both extremes miss the point. Our planet has survived many climate swings in the past, and it will survive this one too. And while it is true enough that many species may struggle in a warmer world, the one whose fate we should really worry about is Homo sapiens.
When temperature and precipitation patterns shift, the organisms hit hardest are the ones with the deepest roots. Unfortunately for us, we humans have a lot of permanent infrastructure. Costal cities cannot move inland to get away from rising sea levels. Farmers cannot simply relocate their fields to the new optimal locations for agriculture. Adaptation is possible--in fact, it is inevitable--but it will not be easy, cheap, or painless.
Unlike other species, though, we can anticipate the environmental challenges that lie ahead and blunt their impact. That is why DISCOVER is teaming up with NBC and the National Science Foundation for two more town hall events exploring how we can best respond to climate change. We are talking not just to scientists but also to the business leaders and policymakers who will put ideas into action. Check back with us again in the September and December issues for more results from those ongoing conversations.
Being smarter about how we use our resources, investing in cleaner types of energy, and studying the adaptation process now will not "save the planet," as some activists so breezily say; the planet is not in peril. What it will do is save ourselves from a lot of future hurt.
[Corey S. Powell, EDITOR IN CHIEF. 2011. The World is not ending. DISCOVER, June, p. 6]
Given that this is occurring, how will it be stopped?
Reply | Report Abuse | Link to this@Bill,
Reply | Report Abuse | Link to thisSo, you are going with the "all scientists who study climatology for a living are members of a vast multi-decadal conspiracy to get a few dollars of research funds even though they are not calling for more research" over the "maybe fossil fuel companies are muddying the waters so they can continue being the most profitable companies on the planet" reasoning. OK, your choice, but it sounds kind of silly when I write it out that way, and I don't think you are going to be very convincing with that argument.
Why Ted Turner' philanthropic notions would have anything to to with it is also a mystery, and one which you leave unexplained, but on which you are willing to bet our future prosperity, over experts who have devoted their lives in studying the climate. OK, got that too.
And finally, global warming will in fact cause loss of human life, loss of biodiversity with concomitant danger of ecosystem failure, increased property damage, increased food and water insecurity, mass human migration, increased incidence of human and animal disease. How do we know? Because we are already beginning to see it.
Will the planet be destroyed? No, and I call "strawman" on that one, as I do on the "alarmist" label. The planet will survive, and I venture to guess humans will too. But the cost will be an enormous amount with no upper limit, and it is completely preventable.
The solution mostly involves stuff we should be doing anyway, like becoming energy independent, decreasing known pollutants (yes, Virginia, including nuclear power), becoming more efficient in how we generate, transmit, and use energy. Complete studies of the economic effects of climate change mitigation show that there is near neutral to slightly net positive, especially when you consider the political ramifications.
If, when presented with all the lines of evidence of human-forced climate change, you still choose to believe it is not happening, that is your prerogative. However, I would support legislation that would hold such individuals personally liable for any damage induced by climate change and their own inaction in the face of overwhelming evidence to the contrary.
So, what probability to you assign to you being right? Are you confident enough to stand up and say that, if in 15 or 20 years deniers have muddled things so much that no action is taken and climate change is occurring and is costing people money, you and your heirs will pay for it?
The AGW agenda of TSA is revealed by the need to regress to a 2008 article that promotes AGW. TSA could just as easily have referenced thousands of peer reviewed articles and books disproving AGW. Worse yet is that in previous posts I have provided links to well researched, peer reviewed scientific studies demolishing the theory of AGW. Why does TSA ignore them?
Reply | Report Abuse | Link to thisIn Nov 2011 the IPCC published a statement that man’s effect on climate in the next few decades will be less than natural forces and may be either positive or negative. All five official Global Climate monitoring agencies report that global temperature has cooled since 1998. There have been two ice age and two run away warming alarms in the last 130 years. Global climate, still warming from the Little Ice Age, is now cooler than it has been for 9,100 of the last 10,500 years.
From 1895/7 the correlation of temperature to CO2 was 0.43; to solar intensity, 0.57; to oceanic oscillations, 0.85. From 1987 to 2007 correlation of temperature to CO2 was 0.02. In the last 600 million years records show CO2 increases about 800 years after the earth warms, not before.
http://wattsupwiththat.com/2008/01/25/warming-trend-pdo-and-solar-correlate-better-than-co2/
World leaders brag that they promote the hoax as a means to impose global government, social justice, population control and redistribution of wealth – all Marxist goals. This promotion has cost hundreds of billions, increased energy cost, and destroyed jobs and economies.
I would like to see TSA discuss the global climate correlations to various natural phenomena. One that is very interesting is the correlation to the 60 year solar system center of mass.
http://www.appinsys.com/GlobalWarming/SixtyYearCycle.htm
@xqzme & priddsereen, dont't you people dare to confuse us with facts and reason. We are the believers of he true faith of AGW. We voted and had a majority decision in favour of AGW. If you don't join us you will burn in hell.
Reply | Report Abuse | Link to thisXQZME, perhaps you could provide the reference to even one of these "thousands" or articles "disproving" AGW? Peer-reviewed articles by climatologists that have been published in a notable scientific journal please? Online denier websites and fossil fuel talking points don't count as science. Perhaps point to even one scientific association that says that AGW isn't true? Sorry, even the Society for Petroleum Engineers doesn't take that position any more.
Reply | Report Abuse | Link to thisHow would Scientific American benefit by perpetuating a hoax that AGW is real? How would fossil fuel companies benefit by muddying the issue? Cui bono?
And, as a person who teaches statistics, you are displaying ignorance when you are talking about correlations like that. It's OK - I can cure ignorance! Maybe not in a comment sized space though. Investigate multicollinearity as a topic. Also "Type I error inflation."
Fanandala, you have a bizarre idea of science. No one would be happier than I if climate change wasn't happening. However, the case is clearer each day that it is. Even prominent AGW skeptics are becoming convinced. Your "religion" argument is strange and uninformed.
Why is it so important to you folks to not act to reduce it? If you know even the most basic risk analysis (multiply the probability of occurrence of an event by the cost if it happens, compare it to the cost of action, decide) you would come to the same conclusion. If you know even basic black body calculations, you can get a first-order estimate that confirms how rising CO2 must change the heat balance of the planet.
I take it that no one has an argument against my previous posting then? When I was a debater, we called that "winning." :)
SteveO (comment 23),
Reply | Report Abuse | Link to thisWill you agree that a good share of the "few" research dollars available for those who find agw behind every blade of grass (if you will) is provided by some division or other of the U.N.? Will you agree that Ted Turner donated 1 billion dollars to the U.N.? Will you agree that Ted Turner has publicly stated his wish to reduce human population by 90%? Will you agree that the most militant claim of those who promote agw is, precisely that, human-caused global warming?
Regarding the "stuff we should be doing anyway," you'll get no argument from me.
My own probability assignment must wait until my questions have been answered.
However, let me turn that question around on you: "...[W]hat probability to you assign to you being right?"
You've touted "all the lines of evidence of human-forced climate change" as if you consider it self-evident. Why, specifically?
Incidentally, if my understanding is correct, in 15 or 20 years, according to current "wisdom," there will be no penalty exacted against me, or anyone else, for inaction because the Arctic/Antarctic melt will have caused enough rise in sea levels to inundate all of us.
In the very beginning it was formation of OZONE layer only that made life possible on Earth.This layer could not be a water tight covering, and had holes in it right from the start. Man in his ignorance of right conduct in context of environmental wisdom, has further damaged this Ozone cover with resulting global warming.
Reply | Report Abuse | Link to thisThere is specific mention in Rig Veda in three mantras, of this phenomenon that talk of a canopy made of a worn out fleece like cover on Earth. The holes in this worn out garment should be healed with greenery and efforts made to prevent further damage this cover.
Damage to this covering on Earth leads to catastrophic atmospheric storms that cause untold damage of life and property.
1.Calamities (like Tsunami) that have immense destructive force to toss and smash on to ground even cows, and complete houses are caused by holes in the worn out garment cover in the space RV2.14.3
2.Act against killers (999) who cause damage to this protective covering by enrolling trillions of hands helped by Indra (rains) –by promoting greenery. RV2.14.4
3.Destroy Demons Rudhikra – cause floods, Namuchi – exploit public during famines who promote dry deserts, stop rains to cause draught and obstruct efforts to prevent loss of food production.RV2.14.5
We now understand how humans can change the climate, and some of its consequences. The ocean has been rising because of the melting of the Greenland glaciers. But the major rise will come with the melting of the Antarctic glaciers. This, however, will take 500 or 600 years. And this relates to a problem with our fellow humans. We had trouble conceptualizing events occurring beyond our lifespan, and certainly beyond the lifespan of our grandchildren. When we have that difficulty, other issues come to the fore: Jobs, a new car, etc. Sweeping the big global warming problem under the rug creates chaos and suffering for future generations. Can anyone really worry about them?
Reply | Report Abuse | Link to thisOwing to the numerous examples of climate change in the distant past, it now seems clear that warm episodes on earth were always associated with high concentration of CO2 in the atmosphere. So there is a relationship, whatever the cause. However this is also proof that in the past, at least, mankind was not the culprit: How should a tiny population of nomadic hunter-gatherer produce any significant effect on the climate? Since the advent of agriculture it's a different story. So should we not simply strike-through the A in AGW, or refrain from exclusively accusing CO2 produced by mankind?
Reply | Report Abuse | Link to thisIt has always been obvious that global warming was occurring; I live in Canada. Fourteen thousand years ago this country was covered by ice sheets thicker than those now covering Greenland. As we emerged from the last ice age of course the climate was warming. Until about a decade ago I thought there was a strong possability that the Luddites were simply preaching their "industry bad" message. Since about 2002, however, the evidence has been overwhelming that what is happening now is different from earlier warming... Vastly accelerated and very dangerous.
Reply | Report Abuse | Link to thisSo many millions of people live in coastal cities now their displacement will cause political upheaval, even wars. Agriculture will fail on a wide scale and oceans will support less life.
It is time to get serious about this.
The vast majority of environment scientists are convinced by hard data that climate change due to mankind is fact and that it represents a serious threat. Deniers must think that mankind is immortal, and continue to act as if some god will pardon all their errors. There is proof of the first sentence but the second reveals the extent of human ignorance.
Reply | Report Abuse | Link to thisAnd to the "blah blah blah" of rebuttal, I quote Pee Wee Herman, "la, la, la; connect the dots"..It's so good to feel young again!
Reply | Report Abuse | Link to thisI just wonder, do you get paid to say this stuff, or do you set yourself up higher than the tens of thousands of peer reviewed scientists who are convinced that AGW is real and dangerous?
Reply | Report Abuse | Link to thisIf you do get paid, you are complicit in the death of millions. If you dwell in the land of wishful thinking, "Have a super sparkly day!"