Can you trust the science?

December 16, 2009

Today we pose the question to our virtual panel of experts, “How far can we trust the science of climate change?”

Join the debate and leave your comments below.


Bjorn Lomborg, statistician and author of “The Skeptical Environmentalist”:

The vast majority of climate scientists tell us that increases in carbon dioxide cause higher temperatures over time. We know that this will mean changes in rainfall, melting of snow and ice, a rise in sea level, and other impacts on plants, wildlife, and humans.

There is still meaningful and important work going on looking at the range of outcomes that we should expect–it is wrong to suggest that “all of the science is in”– but I think it is vital to emphasize the consensus on the most important scientific questions.

With some people drastically under-playing the effects of warming and others significantly exaggerating them, my view is that the careful research of the United Nations panel of climate change scientists, the IPCC, is the best guide to what we can expect from global warming – expecting a temperature increase by the end of the century between 1.6 and 3.8 degreesC (or 2.9-6.8 degrees F) higher than today’s temperatures.

There were disturbing revelations in the “Climategate” files – the stolen emails that showed some of the world’s most influential climatologists going to great lengths to enforce what amounts to a party line on climate change. (See related story here.)

Data that didn’t support their assumptions about global warming were fudged. Experts who disagreed with their conclusions were denigrated as “idiots” and “garbage.” Peer-reviewed journals that dared to publish contrarian articles were threatened with boycotts. Dissent was stifled, facts were suppressed, scrutiny was blocked, and the free flow of information was choked off.

These emails – quite predictably – have been seized on by skeptics of man-made climate change as “proof” that global warming is a hoax. And this is the most unfortunate part of “Climategate.”

Global warming is not a hoax, but at a time when opinion polls reveal rising public skepticism about climate change, this unsavory glimpse of scientists trying to cook the data is simply unhelpful.

The most relevant, significant dialogue today is not about interpretations of natural science, but about the different possible solutions to global warming, and what their costs and benefits would be.

I am not a global warming skeptic. But I am deeply skeptical of our dogged, single-minded pursuit of a policy response to global warming that has failed to work for nearly twenty years.



Knut Alfsen, head research director, Center for International Climate and Environmental Research, Oslo (CICERO):

Of course, science is never (or very seldom) “done” or “finished” in the sense that it provides the full and final answer to a particular question or a set of questions.

At its roots, science is a structured dialog where hypotheses are put forward and tested in various well structured ways.

Occasionally it is possible to disprove a hypothesis, but we almost never get a 100 percent proof of the validity of the hypothesis.

At best it may gain credibility over time as it withstands more and more tests. So in one way we cannot completely trust climate science to come up with the final truth.

If, on the other hand, we more modestly want to know what we currently know of the problem, we can do, as IPCC does, listen in on the ongoing scientific dialog and extract the “current truth” about climate change; its causes, effects and possible remedies.

The field of climate science is lucky in having IPCC to carry out intergovernmental assessments of the “current truths”. The assessments are carried out according to strict procedural rules in a transparent and open way, thus lending credibility to the assessment reports themselves.

Big values are at stake when it comes to climate change. On the one hand, the potential damage of unchecked climate change is staggering. On the other hand the costs of necessary mitigation of greenhouse gas emissions are also substantial.

This explains the intense and highly politicized debate about the science of climate change.

Also the fact that the IPCC assessments are carried out by scientists, while the summaries for policy makers and the synthesis report are negotiated with policy makers, a constellation that leaves out businesses and other special interest groups, makes for heated and unstructured debate between some of these stakeholders and IPCC. We should perhaps work harder to rectify this imbalance.

In conclusion, the science of climate change is neither more nor less trustworthy than other fields of science, it is just the victim of more intense and politicized debate.

In the end, the challenge of climate change can only be met if we are able to bring all parties into the debate and find a common answer to the climate challenge. Quite a challenge in itself!


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Climate science is particularly difficult because the climate takes so long to change, and so it literally takes decades to test a theory. In addition climate science only really started going in the 1960s when ice cores showed the climate was actively changin in the current geological period.

The first paper on global warming, was actually a paper proposing CO2 based warming to explain why the predicted cooling based on the Camp Century Cycles (a now discredited theory) had not happened. The concept of the multiplier to explain why CO2 on its own cannot explain the warming seen in the 20th century, is taken directly from the failure of orbital changes in solaration to explain why the ice ages occurred.

In the 1970s a decade of natural cooling led these scientists to convince themselves that cooling was a real prospect. From 1970-2000, we had three decades, of warming and they have convinced themselves that further warming is a real prospect even though this warming is comparable to other warming in the instrumental record before manmade CO2 and quite within expectation because of natural variation as three warming decades in 15 is very likely statistically.

The null hypothesis is that the climate is varying naturally. There’s no statistical basis to suggest that what we see is not normal pink noise which may appear to the untrained eye as forced changes, but in reality are only a symptom of long term variation inherent in this kind of noise.

And the real clincher for me is that in 2001 the IPCC made a prediction of 0.14-0.58C warming per decade since when it has cooled. And far from saying: “so far it does not look like the data supports the theory” the people I can only describe as delusional are saying: “it is proven beyond doubt”.

This is not science, it is some self-delusional pseudo religion!

Posted by Isotherm | Report as abusive

For me, one of the more interesting things to come out of the Climategate emails was the referral to numerous disputes between the climatologists (Phil Jones, Michael Mann, etc) and various palaeoclimatologists. If you consider the fact that the former were the recipients of large government grants and the latter generally weren’t, one can see why Jones et al wanted to keep the palaeoclimatologists at bay.

How important is it to consider the work of the palaeoclimatologists? Well to use an analogy, it’s like a doctor trying to determine whether a patient is sick or not, knowing the patient’s current temperature but having no knowledge of what is normal temperature for a human.

You may have noted that a lot of criticism of AGW comes from the geological profession. For the record, I’m a geologist. Geologists live, eat and breathe palaeoclimatology because it affects the rocks we study. Perhaps not unsurprisingly, somewhere between 80 and 90% of my peer group consider the concept of AGW to be at best extremely exaggerated or at worst a total fabrication. But of course, we’re not the ones scaring the public and getting the money.

In the last 12 months there have been a large number of peer-reviewed scientific papers challenging the link between CO2 and global warming. Do you see any of these mentioned in the mainstream media? No. You’d think this would be good news but there are obviously other agendas at work here but none of them are based in science.

Posted by djh_au | Report as abusive

A model is a model is a model. A model is not reality.

Remember, very expensive computer models developed for the financial world, allowed the creation of CDO’s, MBS’s, 100’s of trillions (if not 1,000’s of trillions) of derivatives to be created without regulation.

Looking at models instead of reality, created a very real Global Financial disaster, still ongoing around us after over 2 years, and likely to get far worse over the next few years.

Models driven by an agenda to make money, hand over fist.

Many of the same people are involved in the Global Warming Ponzi Scheme too. They are the same ones that bought and paid for politicians, to get them to remove sensible regulation from their ambitious and criminal practices.

With Climate Models, nobody in their right mind could claim that the models are anywhere near adequate for the supposed purpose, and this is agreed to be the case. The models are massively simplified.

Then, add in severely compromised databases (commented in the UEA files, remember), which have a significant word in their name – *data*bases. Compromised databases therefore equal compromised data.

Selected data sources (a high predomination of ‘heat island’ inclusion, and exclusion of remote data with no heat island effect, strongly confirms ‘agenda’ rather than science), along with ‘fudging’ of the data itself, to fit the ‘agenda’ of a desired result, is indeed, not science.

To me, it is ‘anti-science’ and ‘junk science’.

To then have once respected Organisations and Publications, collaborate in reinforcing an ‘agenda’ rather than ‘science’ is particularly damning, damaging to real science, and smells strongly of criminal racketeering (although this reflects wrongly on genuine criminal racketeers, such as the Mafia, who I think, would never stoop this low – they do at least seem to have ‘some’ morals and principles).

Very good, very real, very honest scientist, have been ‘blackballed’ out of the climate research and publication world, for years.

Scientists standing up for science, have lost their jobs, and lost their funding, for refusing to toe the line of an ‘agenda’.

These crooks have damaged real science in the process, which to me as an unforgivable sin.

Just what the heck has been going on? Whatever it is, it’s far bigger than we could have dreamed possible prior to the released UEA CRU files and e-mails (and the files are far more damning than the e-mails, bad enough as the e-mails are). A lid has been ripped off something ugly, far ranging, has serious implications, and begs the truly bigger question, which isn’t ‘Where is the Science’?

Where is the Rule of Law, where are the Police, where are the Investigations, where are the Prosecutions? Where has our Media been? Where has investigative journalism been hiding?

Plus, ‘Where have they all been the last 20+ years?’

Posted by Ogri | Report as abusive

Regaring the stolen e-mails at East Anglia:
Mr. Lomborg, what data was “fudged”? As I understand it there was one reff to “fixing” data and that was explained a number or times as something quite scientifically legitimate. Data was correlated to other measurements in order to bridge gaps in a broad research trend, as I understand it. Data was not changed or falsified or left out because it was not liked.
Isn’t it required to mention what data was “fudged” when one makes such a (very serious) allegation?
It is like saying “you are lying” without saying what the lie is.
Besides – since when does East Anglia have the only research regarding global warming? The e-mails were stolen only at East Anglia, is it not?
I mean, MIT, Nasa, Cambridge, the Max Planck Institute, Stanford to name a few from the top of my head were not involved, were they?
Your piece has little argument or science but a lot of, what shall we call it? Politics?
It is not to be taken seriously in a situation that may lead to thousands dying where I live.

Posted by Ferdinand | Report as abusive

Very cogent article and follow up comments. I too took a degree in geology many years ago. Anyone who spends several years studying the subject cannot fail to begin looking at natural pheonomena over the vast sweep of geologic time vs. the current few years or few hundred years. Species come and go, mountains are made and washed away, and climate changes for reasons either understood or legitimately theorized.

However, the current emotional furor around the subject of climate change, not to mention the huge amounts of money and political capital that are at stake, seem to be over-riding or casting doubt on whatever objective science may be included in the debate. And let’s not forget that scientists themselves are only human. As has been pointed out, they too can become defensive of their hypotheses to the point of losing objectivity.

Nobody could argue that pollution, in and of itself, is good. But it is important to recall that so far, pollution controls have, for the most part, been implemented only by economically strong states. That’s why it’s so important to spend our resources wisely and not emotionally. This is true for any work in the public domain, environmental or otherwise. If we spend emotionally or for selfish political reasons, we kill the goose that’s laying the golden eggs through massive deficits and taxation – but that’s another story.

Like most people, I don’t know if we’re facing a man-made climate change scenario or not. And if we are, persuasive evidence that we objectively understand its timing, depth, and consequences has not appeared in the news media. Models are fine, but as another commentor noted, they are not reality. However, so as not to discount the possibility that some action is warranted, I for one would like to see some priorities established with customary cost/benefit analylses. Then let those priorities stand for scrutiny alongside our many other national and global priorities. By this and/or other means, and also with time and renewed objectivity, credible evidence may begin to emerge.

Posted by John-B | Report as abusive

Between 800 – 1200 AD the Vikings settled in Greenland. This was during the Medival Warm Period (MWP), and records show that they farmed the land and had a good life…..until the mini-ice age came and they left because it got too cold to farm there. It may have been a bit warm lately but nobody is farming in Greenland….and the MWP wasn’t caused by CO2. So the science can’t be trusted.

Posted by timberlinesc | Report as abusive

In my many years on this earth I have come to firmly believe that ‘everything’ is about the almighty dollar and climate change is no different than the coffee crises, oil crises, Y2K, and the sub-prime mortgage debacle. It drives the economy to the loss of our own base income through increased taxation, increased pricing on everything, and decreased standard of living. I mean, we have enjoyed and prospered therefore, we must now pay the piper?

I, for one, am sick to death of hearing every negative occurrence on earth now blamed on climate change. When one looks back on history years from now, one will just cringe. We shall see how prosperous (medically, physically, mentally) we once were, and how we just had to put a kybosh on it all. Maybe this is what really happened to the great cultures of history!

The young and the special interest groups, those who are core at pushing this agenda (although they have no idea they are pawns in it), and the young who have no real experience in the history of mankind and what we are capable of in believing, pursuing, and destroying in the name of money, will only be satisfied when we are living in caves once again. They seem to romanticize about the past and how simple life was. This was not the case. Gathering wood before you can cook, hunting, fishing, growing foods et al is extremely hard work. And all that before you can even put a bite of food in your mouth. We are living longer and we can reap the fruits of the aged because they harbor more real knowledge – not the made up knowledge that is passed through the media and then scribed into magazines and books to become the ‘new history’. The majority of people in the Western world are baby boomers – over 45. We know and understand how mankind works. But, no one is listening.

We all know that wealth and power is shifting to the East and the climate change scheme is only quickening this agenda. Those in the East (Asia and Africa) are chomping at the bit to get the carbon credit going. They can continue to progress while we regress. They can surpass us at our expense. It seems that: the bigger the lie the more believable it is. Maybe this time you can get on the bandwagon and invest in the carbon trading commodity scheme – at least in the beginning, because it too will bring down the economy eventually.

Fool me once, shame on you, fool me twice, shame on me. How many times has it been now?

Laurie in Canada

PS…for the record Canada emits 2% of the global output of carbon and the oil sands represents .5% of that. Wow! Let’s all freeze in the dark, get ill, and die early, leaving the young to repeat history over and over because the knowledgeable elderly are gone.


Posted by LDB | Report as abusive

Does anyone know how much global deforestation contributes to changing CO2 levels? If trees and other vegetation process and eliminate our CO2, and we are not replacing the earth’s capacity to process CO2, it would seem logical that this should be considered in discussion if the amount is significant.

Posted by Curious2 | Report as abusive

I find it very odd that both the pro and con statements above have glowing opinions of the IPCC. When I was working on my last graduate degree, we were always careful to include journals citing results from distant lands. Why on earth would anyone assume that countries don’t share data unless there’s an international interest group forcing them? Science does not include threats, payoffs, or political action commitees… that’s the opposite of science. To paraphrase Ayn Rand, science ends where force begins. If the data was so clear, why the bombast? I generally assume that when the opposing counsel is pounding the table, he has neither the facts nor the witnesses supporting his suit.

Additionally, why would anyone die? Wouldn’t we just move inland, change our lifestyles according to supply and demand and continue to make the small choices everyday according to our own personal best interests? I don’t understand why the image of people standing still as the water rises around their feet is so compelling.

Growing trees consume CO2. Rotting trees put it all back into the air. If we were serious about CO2, we’d clear-cut the earth and replant it all with slow-growing species.

Posted by midwestguy | Report as abusive

Deforestation is a significant contribution to human emissions of CO2, but also soil degradation. More carbon is stored in the Earth’s soil than in all the trees on Earth. Soil carbon losses caused by agriculture account for a tenth of total CO2 emissions attributable to human activity since 1850.

This IS part of the discussion, but more on the deforestation side; unfortunately soil carbon sequestration has been a bit of a blind spot.

Look at the UN-REDD Programme. Reducing Emissions from Deforestation and Forest Degradation.

Posted by Sc0tt | Report as abusive

You conclusions are highly dubious at best. Indeed why wouldn’t we just move inland LOL. Unless you’re on a small island nation, where are you going to go? Or when the glaciers on the Tibetan Plateau, which are retreating at an accelerated rate, stop feeding melt water to major rivers in Asia and a BILLION people don’t have water, where do you think they’re going to go? They ARE going to move, across political boundaries stressing and destabilizing entire regions and leading to eventual military conflict. I wonder why the Pentagon lists climate change as a global security threat? No biggy though right.

Posted by Sc0tt | Report as abusive

Your response is so typical of the difficulties presented by those who argue in favor of immediate political/economic solutions to the supposed AGW. A collection of “if’s” presented as the known future reality. It sounds very scarey to think of a BILLION people out of water as a result of AGW. Is this Nostradamus-like beating of the drums science? None of us can say, with any degree of certainty, what the future state of the planet will be; certainly not wrt global climate.

I’m in favor of a mindful energy policy, just not this forced, global solution, engineered by folks with questionable agendas.

Posted by folson805 | Report as abusive

Trust? Don’t trust? Believe? Don’t believe?

Political football is a lively game for science, isn’t it?

CO2 is one molecule, what about methane and any number of other potentially damaging molecules and compounds lurking in our midst wreaking havoc on our climate?

“That science stuff is just a bunch of elitist academics who believe they know more than the rest of us don’tchaknow.” (thanks Sarah!)

What is known is that the world is warming, glaciers are waning at far quicker than expected rates in almost every corner of the globe. Sea levels are rising with the probability of drowning coastal cities if trends continue. Entire eco systems like the Great Barrier Reef are in decline.

What is also known is that man’s impact on the world has never been greater. 500 years ago man was not the predominant species on the planet, today man holds dominion over the land, seas and skies, and can wipe out entire species at will. Pollution in the form of toxic compounds not found in nature can be seen floating in a massive slurry the size of Texas in the Pacific Ocean.

Should we turn a blind eye to the propogation of unmonitored factories and mass production of machines that spew compounds into the air and water capable of genetic mutations across species and catastrophic impacts to whole eco systems? Should we say to hell with caring about the consequences, known or unknown, about anything we do so long as we can create economic growth and prosperity today?

Whether by design or evolutionary happenstance we find ourselves as the stewards of this planet and our capacity to understand our potential (and real) impact has never been greater. It is our collective obligation to do all we can to pay attention and regulate when and where necessary.

If the anti-man-made-global-warming advocates win the public opion war, what then? To what end for the next call to action, especially if they are wrong? Given the likely scale, we won’t have much of a window of opportunity to reverse course or slow our activities if mankind is to blame; but then, politically speaking, who cares about the consequences for tomorrow? That would then be someone elses problem…or perhaps the intended design…

Frighteningly, many of my counterparts to the far right end of the political spectrum hold firmly to a notion that God’s plan is to end the world in fire some time in the not too distant future anyway, so what we do today, for good or evil, matters not. Religious fatalism, ecologic indifference, and unapologetic greed make for a fine combination for our collective earth bound futures.

Let’s call this current shift the Black Earth Movement, and if you are in favor, vote Republican, make all science illegal, and convert to a young-earth, no-evolution promoting religion as quickly as possible.

Posted by NobleKin | Report as abusive

there is one way to prove climate warming is CAUSED by 20th century industrial technique based on carbon buring: ‘go ape’ with carbon burning on mars and see if that significantly heats up mars’ atmosphere! this could be done robotically after finding a large enough coal deposit on mars (which can also be done robotically). in the mean time, we just do nothing differently here. after a sufficient amount of time, just compare results. (of course, it might be too late for humans at that point, but i’m sure the cockroaches will appreciate the data whenever they’re able to decipher them!)

Posted by jborrow | Report as abusive

iborrow. There probably isn’t coal on Mars, unless Mars used to have thriving eco-systems.

Posted by Jarlent | Report as abusive

[…] Global environmental challenges […]

Posted by Go Green Toolshed » Blog Archive » Global environmental challenges | Report as abusive

No need to go to Mars. Just look at Venus. Why is Venus warmer than Mercury?

Posted by Sc0tt | Report as abusive