Survey: Scientists agree human-induced global warming is real

January 19, 2009,

While the harsh winter pounding many areas of North America and Europe seemingly contradicts the fact that global warming continues unabated, a new survey finds consensus among scientists about the reality of climate change and its likely cause.

A group of 3,146 earth scientists surveyed around the world overwhelmingly agree that in the past 200-plus years, mean global temperatures have been rising, and that human activity is a significant contributing factor in changing mean global temperatures.

Peter Doran, University of Illinois at Chicago associate professor of earth and environmental sciences, along with former graduate student Maggie Kendall Zimmerman, conducted the survey late last year.

The findings appear today in the publication Eos, Transactions, American Geophysical Union.

In trying to overcome criticism of earlier attempts to gauge the view of earth scientists on global warming and the human impact factor, Doran and Kendall Zimmerman sought the opinion of the most complete list of earth scientists they could find, contacting more than 10,200 experts around the world listed in the 2007 edition of the American Geological Institute's Directory of Geoscience Departments.

Experts in academia and government research centers were e-mailed invitations to participate in the on-line poll conducted by the website Only those invited could participate and computer IP addresses of participants were recorded and used to prevent repeat voting. Questions used were reviewed by a polling expert who checked for bias in phrasing, such as suggesting an answer by the way a question was worded. The nine-question survey was short, taking just a few minutes to complete.

Two questions were key: have mean global temperatures risen compared to pre-1800s levels, and has human activity been a significant factor in changing mean global temperatures.

About 90 percent of the scientists agreed with the first question and 82 percent the second.

In analyzing responses by sub-groups, Doran found that climatologists who are active in research showed the strongest consensus on the causes of global warming, with 97 percent agreeing humans play a role. Petroleum geologists and meteorologists were among the biggest doubters, with only 47 and 64 percent respectively believing in human involvement. Doran compared their responses to a recent poll showing only 58 percent of the public thinks human activity contributes to global warming.

"The petroleum geologist response is not too surprising, but the meteorologists' is very interesting," he said. "Most members of the public think meteorologists know climate, but most of them actually study very short-term phenomenon."

He was not surprised, however, by the near-unanimous agreement by climatologists.

"They're the ones who study and publish on climate science. So I guess the take-home message is, the more you know about the field of climate science, the more you're likely to believe in global warming and humankind's contribution to it."

Doran and Kendall Zimmerman conclude that "the debate on the authenticity of global warming and the role played by human activity is largely nonexistent among those who understand the nuances and scientific basis of long-term climate processes." The challenge now, they write, is how to effectively communicate this to policy makers and to a public that continues to mistakenly perceive debate among scientists.

Source: University of Illinois at Chicago

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3.3 / 5 (15) Jan 19, 2009
Too bad they didn't ask them if this warming was likely to be catastrophic within 100 years.
I wish I could read the rest of the questions and answers
4.1 / 5 (12) Jan 19, 2009
Surely a polling expert would have something to say about subjectivity as well as bias.

How can a word like 'significantly' be used in the defining question of the survey without defining what significant is?

I'm sure that a climatologists idea of significant is somewhat different to that of a meteorologist, especially if the meteorologist is indeed thinking short-term and the climatologist long-term.
3.2 / 5 (13) Jan 19, 2009
The question that was missing is "How much effect do you feel CO2 emissions have on Global Climate Change?". Because no one ever talks about how the growth of cities and the reduction of forests affects climate change.
3.6 / 5 (16) Jan 19, 2009
Since when did scientific truth flow from a poll? Since when is an Entymologist, for example, an expert on anthropological climatology? Is this even a "scientific" poll, a representative sample? Even if it is, it's just silly. Design an experiement. Gather data. Test the null hypothesis. BTW, compute models don't generate data. They give us clues as to what to measure.
3.3 / 5 (12) Jan 19, 2009
So I guess the take-home message is, the more you know about the field of climate science, the more you're likely to believe in global warming and humankind's contribution to it.
So I guess the take home message is, if you're predisposed to determine who responded correctly or incorrectly in the survey, the more you're likely to justify the tail wagging the dog.
4.2 / 5 (10) Jan 19, 2009
All I can say to the comments from Doug57 and OregonWind is Amen! Science does not work like a democracy,but rather by putting forward a hypothesis and testing it.
3.3 / 5 (15) Jan 19, 2009
3,146 earth scientists surveyed around the world overwhelmingly agree? You would think that an article like this would note that more than 31,000 scientists think that there is no convincing evidence that global warming exists (Go to
2.8 / 5 (9) Jan 19, 2009
3,146 earth scientists surveyed around the world overwhelmingly agree? You would think that an article like this would note that more than 31,000 scientists think that there is no convincing evidence that global warming exists (Go to ).

3.7 / 5 (18) Jan 19, 2009
The reasons that climatologists and meteorologists disagree is quite simple. The meteorologist works with weather extremes on a daily basis and develops a good sense of both normal and unusual ranges of weather. He recognizes the hype and gross exaggerations of climate alarmists, whereas the climatologist's next paycheck is dependent on the that hype and gross exaggeration generating new research.
3.1 / 5 (13) Jan 20, 2009
How sad - global temperatures have been dropping for 10 years now, and the 'believers' are so wedded to a patently false (and politically motivated) 'theory' that they can't see even the snow piling up around their homes!!!
3 / 5 (18) Jan 20, 2009
Those "scientists" should read the article at:


My favorite quote from the article is to the effect that it was warmer at the end of the last Ice Age than it is now, and that they do not know why. There were no manmade emissions at that time, ergo, AGW is a crock...
2.6 / 5 (15) Jan 20, 2009
That Man IS effecting climate is obvious, no real sceptic doubts it. Land use change is the main one, especially changing humidity. The urban heat island effect must put heat into the atmosphere at some level apart from giving false GISS temp readings.
Then we have the natural effects such as changes in Earth's orbit,El Nino,La Nina,cosmic rays on cloud cover. I could go on (and on and on) but you get the point.
All these have been shown to be true at varying levels, all eating away at the Carbon Dioxide is the Main driver consensus. If you have thirty or forty man made or natural causes each of 1 to, say 20% effect, perhaps not all at the same time, you don't have much left for the greenhouse effect.
4.5 / 5 (8) Jan 20, 2009
A survey is not based on scientific data and not based on facts but on opinions only.

Science = not religion or believes
2.6 / 5 (7) Jan 20, 2009
90% of any population is usually ignorant. This poll proves my statement.

I am for clean technology and recycling. I say punish the litter bugs simply because of their lack of compassion and respect for themselves and others.

Most scientists know how to memorize words and equations while performing arithmetic (quite ignorant). On the other hand, people who have no faith-based assumptions are the people I would rather listen to. Unbiased polling is no indicator to the truth of a disposition.
2.3 / 5 (12) Jan 20, 2009
FTA:"The challenge now, they write, is how to effectively communicate this to policy makers and to a public that continues to mistakenly perceive debate among scientists."

Oh we KNOW there is no "debate" amongst people who know their paychecks are tied to a theory. What we reject is....*gasp* their CONCLUSIONS. We, the great unwashed masses know that argument from authority is a logical fallacy.

The challenge now is how to communicate to the climatology (notice I didn't say scientific) community that they're ACTUALLY going to have to prove their case SCIENTIFICALLY far more convincingly than they have thus far, and the "just take our word for it and hand over the grant money" line JUST ISN'T WORKING....
2.5 / 5 (13) Jan 20, 2009
The policy of those behind AGW is not to advance empirical science and rational debate, but to excite a uniform perception throughout the developed world. These people know that most people are quite ignorant of the most basic functions of nature, and will not consider the matter any deeper than the information that is provided to them by media. This is why the campaign of AGW propaganda focuses on creating a sense of immediate crisis in a population group that really has no scientific understanding. The only relationship the target population has with this information is the ability to be taxed, and in order to tax them at the exorbitant rates desired they must first be convinced of the utter necessity of it. This is the heart of it, and it is only the beginning of how societies will be governed in the increasingly authoritarian world of the 21st century.
2.8 / 5 (11) Jan 20, 2009
As opposed to your plan, Arkaleus? What system would you prefer over informing all voters of the facts of a situation?

Yeah because the voters are NEVER lied to or manipulated by people in authority...

What planet exactly are you from? Is it called Earth? Third one from its sun? Mostly blue....?
3.3 / 5 (14) Jan 20, 2009
Plan? What plan? Science is not ideology. There is not a sufficient understanding of climate, its causality, or its relationships to the life systems of this earth to justify presenting this information as a crisis. We must continue to study and observe until we are certain of the mechanisms of climate and can inform the governments of the world with real information, not this transparaent attempt at social engineering that is nothing more than the framework of nearly total control over all human activity. The world's climate changes frequently and has been doing so long before man came to be, and we need to approach our ecological conservation policies rationally, calmly, and ready with knowledge. Otherwise we risk allowing scheming elements of power to use the ignorance of people to create systems of control based upon fallacies of manufacured crises. If you are so naive as to not understand what motivates powerful groups, and the methods they use to attain power, then you will be confused and at the mercy of those who have made plans for this century that might not be in your best interests.
3.5 / 5 (13) Jan 20, 2009
A broad consensus by definition precedes every paradigm shift. If we stuck with the broad consensus, we'd still believe the sun orbited the Earth.

What a load of hooey! The overwhelming evidence is that the Earth is cooling down.

2.5 / 5 (10) Jan 20, 2009
Read "How to Lie With Statistics" by Huff & Geis
( and you'll never trust a survey again (if you believe them now.)
1.7 / 5 (12) Jan 20, 2009
Wow, it's almost embarassing to see the reich wing deniers on this site grasping for straws. It's actually quite sad.
2.5 / 5 (11) Jan 20, 2009
what percentage of the polled "earth scientists" make their living by working on AGW in one way or another? ALL should have been disqualified.
4.3 / 5 (6) Jan 20, 2009
I observe leftists on this thread launching personal attacks on sceptics (kindly referred to as reich-wing-deniers) comments. I agree that climate science has become so politicized and heavily dependant on government research funding that climate scientists daren't knock the AGW theory. It would be akin to me running around the office telling my colleagues that our company's business plan is flawed and its senior managers don't know what their doing. Even if it were true, I think if I was to voice my opinion I would have another job lined up in a different discipline first. By this time next year we surely will know if solar cycles are really the chief driver of climate change. Maybe then AGW advocates (see, it's not hard to be charitable and lose the name-calling abuse) will start to look subjectively at both sides of the debate.
1.4 / 5 (11) Jan 20, 2009
I'm no leftist(closer to libertarian) but more then 90% of people commenting here would not be denying AGW global warming if they were not listening to the reich wing radio/news programs and that%u2019s a fact.

Hey kids how do you think theories end up in science books??????
It usually peered reviewed and when enough scientists can agree on it (consensus) then it would most likely be incorporated into text books.

But the beautiful thing about science is that the truth will always prevail.

I%u2019m still trying to figure out how all this scientific organizations that believe in AGW are on the take. I mean this would be unprecedented:

InterAcademy Council
Joint science academies' statement 2008
Joint science academies%u2019 statement 2001
International Council of Academies of Engineering and Technological Sciences
Network of African Science Academies
National Research Council (US)
European Science Foundation
American Association for the Advancement of Science
Federation of American Scientists
World Meteorological Organization
Royal Meteorological Society (UK)
Australian Meteorological and Oceanographic Society
Canadian Meteorological and Oceanographic Society
Canadian Foundation for Climate and Atmospheric Sciences
International Union for Quaternary Research
American Quaternary Association
Stratigraphy Commission of the Geological Society of London
International Union of Geodesy and Geophysics
International Union of Geological Sciences
European Geosciences Union
Canadian Federation of Earth Sciences
Geological Society of America
American Geophysical Union
American Astronomical Society
American Institute of Physics
American Physical Society
American Chemical Society
American Society for Microbiology
Institute of Biology (UK)
World Federation of Public Health Associations
American College of Preventive Medicine
American Public Health Association
American Medical Association
American Statistical Association
Engineers Australia (The Institution of Engineers Australia)
Water Environment Federation
Chartered Institution of Water and Environmental Management
Federal Climate Change Science Program (US)
Royal Society of New Zealand
4.2 / 5 (5) Jan 21, 2009
I too could produce a list of hundreds of organizations who agree that we should be sceptical about man's contribution to GW. But thats not the point. The real issue that most sceptical scientists point to is the fact that CO2 has not been proven to be the main driver of our climate. Even the IPCC documents that man-made geen-house gases have "likely" raised temperatures during the 20th century by 0.6-0.7 decC. This is based on historical data and analyzed by a couple of dozen computer models which then try to produce projections many decades ahead. It is these projections and the IPCC's summary of dire possible consequences that sceptics are challenging.
There are plenty of publications showing very close correlations between solar activity and temperature of the planet. The correlation between CO2 and temperature is also well documented, however CO2 levels lag temperature by 600-1000 years.
The naturally occurring greenhouse gases in the atmosphere make up 99.72% of all greenhouse gases. The contribution by man is 0.28%.
There is still a lot of uncertainty as to complexity of forcings or feedback effects if CO2 increases in the atmosphere. For example, increased low level clouds are more likely to reflect the more radiation back into space.

It is great to reduce pollution and develop cleaner energy sources. Lets clean up our act. But CO2 is not the pollutant we should be concerned about.
Spending hundreds of billions of dollars on the assumption that it is, is wasteful. Biofuel production is not only taking away food from already starving millions it is indirectly promoting the clearing of forests to grow more biofuels. ..
Commonsense should prevail. Lets learn to adapt to climate change because we are really doomed if we think we can control it!
2.5 / 5 (8) Jan 21, 2009
I'm no leftist(closer to libertarian) but more then 90% of people commenting here would not be denying AGW global warming if they were not listening to the reich wing radio

WHAT? The left wing are the ones touting AGW! Plus there are not that many left wing radio talk shows. I think you might be confusing your pejorative "Reich" (assuming you mean the third Reich) with right wing politics.

The Nazis (ie third Reich) were socialists...that's LEFT wing. The right wing has (traditionally at least) not been a political entity with socialist leanings. True they were nationalists which is more right wing, but most of their policies (other than the racial ones) were taken out of the modern play book of socialism...including things like AGW (again a form of thinly disguised socialism).

If you're trying to be clever with words, you might do more research on the meaning of your perceived insults.
4 / 5 (4) Jan 21, 2009
It is funny how 25% of Scientists agree human-induced global warming is real makes headlines. Out of over 10,200 only 3,146 replied and of that 82% agreed humans induced global warming. Where is the news?
1.5 / 5 (8) Jan 21, 2009
I know , I know, the world scientists are in cahoots. They are all scamming.

All these climatologists are in on it for political reasons because they hate America. You guys really sound very silly. Do you even know the # of climatologist that accept this theory??? I understand consensus is not science but the people that are experts in this area of study agree overwhelming about AGW conclusions based on the science and testing that is now available.

I guess people like stephen hawking is also in on it or has been duped.

How many of you heree work for big oil or the American enterprise institute.
1 / 5 (6) Jan 22, 2009
The septics of physorg strike again. This community has really gone to the shitter, sad to say. It's so cute though to see the pseudo-academic "I hold a degree in chemistry" types attempt their pop-review. Charming really. You have to wonder how long they can keep it up though. Are you all still going to be spouting this stuff in another decade? Two?
5 / 5 (1) Jan 22, 2009
I think the word "warming" will be replaced with the word "cooling" but the conversation will remain the same. You know, like it did 2 decades ago.
CRAP!! Al Gore's gonna come back in 20 years?!... or is it 40?
5 / 5 (3) Jan 25, 2009
Notice that the "survey" gave no NAMES. The "survey" is a deliberate attempt by AGW alarmists to distort truth.
31,072 real names of real scientists tell the true story...
4.6 / 5 (5) Jan 25, 2009
The first question- "have mean global temperatures risen compared to pre-1800s levels?"- has an answer, and that answer is a FACT. Odd how only 90% of scientists knew their facts. Makes me want to discount 10% of the answers to the second question.

The second question being: "has human activity been a significant factor in changing mean global temperatures?" This is not a fact, and any answer to this would be an opinion. I wonder, was 'I don't know' a possible answer? I hope so.

This whole Global Warming debate is completely off track. We KNOW how human's have impacted the environment. We DON'T know if that impact is warming. The FACT is that CO2 in the atmosphere has risen as a result of humans. That cannot be argued. The survey should be asking, is there a correlation between an increase of CO2 and a change in the environment, and, if so, what is that correlation? My answer would be 'I don't know', but then, I'm not a scientist.
2 / 5 (4) Jan 31, 2009
The first question- "have mean global temperatures risen compared to pre-1800s levels?"- has an answer, and that answer is a FACT....

Yet, people seem to forget that we were just coming out of what was known as the Little Ice Age by 1815 or so. Of course temperatures would be on the rise from that time to the present. That is a given. That is a fact. Trouble is, IPCC and others of their ilk miscontrue that "fact" and bend it to their political bent. :)

And, again, let's not forget that the end of the last major glaciation, what is most commonly known to be what is called the Ice Age, was warmer then than now, and that climate scientists do not know why that is. Yet, that is a fact. It was warmer at the end of the last major Ice Age than it now is.

BUT, there were no manmade emissions at that time.

If it was warmer way back when, why are we worrying when the temps begin climbing again and have not reached temps at the end of the major Ice Age???

When will people begin to think for themselves rather than bleat blissfully after the "Gore shepherd"? :)
2.6 / 5 (5) Feb 04, 2009
I'm no leftist(closer to libertarian) but more then 90% of people commenting here would not be denying AGW global warming if they were not listening to the reich wing radio/news programs and that%u2019s a fact....

I don't much listen to any radio, and when I do it is for music rather than commentary of any kind. I hate talk shows.

As to what I know, I do not have to rely on the information supllied by others. I can monitor CO2 levels and global temperatures for my self. CO2 has gone up and global temperatures have been falling. These are empirical facts.

In fact, the winter of 2008 has been touted as "the coldest winter of the 21st century." I have certainly seen a downtrend in global temperatures. 2008 certainly was colder than 2007 and 2007 was colder in turn than 2006 and so on to 2005. Europe got hit with a blast of Saharan air but that was an anomaly.

Arctic ice mass is on the increase, as is Antarctic ice mass. That is not consistent with global warming on the scale advocated by the people in the list you have given.

On polar bears, not related on the surface to your claims, etc., they first made their appearance millions of years ago, and survived warm periods warmer than any presently occuring. In fact, new fossil evidence (in the form of a fossilized fresh water turtle that was swimming across the Arctic when it died!) shows that millions of years ago the Arctic was nearly a freshwater ocean at the surface as a result of warming and the melting of most of the ice thereby. Polar bears survived the loss of Arctic ice at the end of the last Ice Age, too, when global temperatures were higher on the order of several degrees C than temps are now!

Tell Gore to put that in his pipe and smoke it. :)

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