A Summary Of The Not So Settled Science of Anthropogenic Global Warming

Over the weekend came a series of revelations and admissions by one of AGW's most influential figures, the current head of East Anglia University's Climate Research Unit (CRU), Phil Jones (technically, he is on leave). His bombshells concerning paleoclimatalogical data, the Medieval Warming Period and its ramifications, and the current period of alleged global warming are a dagger in the heart of AGW. Also over the weekend, yet another major research paper documented that modern climate records are untrustworthy and have been significantly manipulated.

To prove the theory of AGW, climate scientists had to show that global warming is occurring at a historically unprecedented rate and that such warming is caused by human emissions of carbon dioxide. Yet, in light of Climategate and revelations both before and since, it would appear that the "unequivocal" and "settled" theory of AGW is anything but.

Why AGW Is Now In Tatters

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Update: This speech from climate scientist Dale Evans, a long time proponent of AGW, spells out why the theory is, one, still alive, and two, provably false:

. . .The whole idea that carbon dioxide is the main cause of the recent global warming is based on a guess that was proved false by empirical evidence during the 1990s. But the gravy train was too big, with too many jobs, industries, trading profits, political careers, and the possibility of world government and total control riding on the outcome. So rather than admit they were wrong, the governments, and their tame climate scientists, now outrageously maintain the fiction that carbon dioxide is a dangerous pollutant.

Let’s be perfectly clear. Carbon dioxide is a greenhouse gas, and other things being equal, the more carbon dioxide in the air, the warmer the planet. Every bit of carbon dioxide that we emit warms the planet. But the issue is not whether carbon dioxide warms the planet, but how much.

Most scientists, on both sides, also agree on how much a given increase in the level of carbon dioxide raises the planet’s temperature, if just the extra carbon dioxide is considered. These calculations come from laboratory experiments; the basic physics have been well known for a century.

The disagreement comes about what happens next.

The planet reacts to that extra carbon dioxide, which changes everything. Most critically, the extra warmth causes more water to evaporate from the oceans. But does the water hang around and increase the height of moist air in the atmosphere, or does it simply create more clouds and rain? Back in 1980, when the carbon dioxide theory started, no one knew. The alarmists guessed that it would increase the height of moist air around the planet, which would warm the planet even further, because the moist air is also a greenhouse gas.

This is the core idea of every official climate model: For each bit of warming due to carbon dioxide, they claim it ends up causing three bits of warming due to the extra moist air. The climate models amplify the carbon dioxide warming by a factor of three — so two-thirds of their projected warming is due to extra moist air (and other factors); only one-third is due to extra carbon dioxide.

That’s the core of the issue. All the disagreements and misunderstandings spring from this. The alarmist case is based on this guess about moisture in the atmosphere, and there is simply no evidence for the amplification that is at the core of their alarmism.

Weather balloons had been measuring the atmosphere since the 1960s, many thousands of them every year. The climate models all predict that as the planet warms, a hot spot of moist air will develop over the tropics about 10 kilometres up, as the layer of moist air expands upwards into the cool dry air above. During the warming of the late 1970s, ’80s and ’90s, the weather balloons found no hot spot. None at all. Not even a small one. This evidence proves that the climate models are fundamentally flawed, that they greatly overestimate the temperature increases due to carbon dioxide.

This evidence first became clear around the mid-1990s.

At this point, official “climate science” stopped being a science. In science, empirical evidence always trumps theory, no matter how much you are in love with the theory. If theory and evidence disagree, real scientists scrap the theory. But official climate science ignored the crucial weather balloon evidence, and other subsequent evidence that backs it up, and instead clung to their carbon dioxide theory — that just happens to keep them in well-paying jobs with lavish research grants, and gives great political power to their government masters.

There are now several independent pieces of evidence showing that the earth responds to the warming due to extra carbon dioxide by dampening the warming. Every long-lived natural system behaves this way, counteracting any disturbance. Otherwise the system would be unstable. The climate system is no exception, and now we can prove it.

But the alarmists say the exact opposite, that the climate system amplifies any warming due to extra carbon dioxide, and is potentially unstable. It is no surprise that their predictions of planetary temperature made in 1988 to the U.S. Congress, and again in 1990, 1995, and 2001, have all proved much higher than reality.

They keep lowering the temperature increases they expect, from 0.30C per decade in 1990, to 0.20C per decade in 2001, and now 0.15C per decade — yet they have the gall to tell us “it’s worse than expected.” These people are not scientists. They overestimate the temperature increases due to carbon dioxide, selectively deny evidence, and now they conceal the truth.

One way they conceal is in the way they measure temperature.

The official thermometers are often located in the warm exhaust of air conditioning outlets, over hot tarmac at airports where they get blasts of hot air from jet engines, at waste-water plants where they get warmth from decomposing sewage, or in hot cities choked with cars and buildings. Global warming is measured in 10ths of a degree, so any extra heating nudge is important. In the United States, nearly 90% of official thermometers surveyed by volunteers violate official siting requirements that they not be too close to an artificial heating source.

Global temperature is also measured by satellites, which measure nearly the whole planet 24/7 without bias. The satellites say the hottest recent year was 1998, and that since 2001 the global temperature has levelled off. Why does official science track only the surface thermometer results and not mention the satellite results?

The Earth has been in a warming trend since the depth of the Little Ice Age around 1680. Human emissions of carbon dioxide were negligible before 1850 and have nearly all come after the Second World War, so human carbon dioxide cannot possibly have caused the trend. Within the trend, the Pacific Decadal Oscillation causes alternating global warming and cooling for 25 to 30 years at a go in each direction. We have just finished a warming phase, so expect mild global cooling for the next two decades.

We are now at an extraordinary juncture. Official climate science, which is funded and directed entirely by government, promotes a theory that is based on a guess about moist air that is now a known falsehood. Governments gleefully accept their advice, because the only ways to curb emissions are to impose taxes and extend government control over all energy use. And to curb emissions on a world scale might even lead to world government — how exciting for the political class!

Even if we stopped emitting all carbon dioxide tomorrow, completely shut up shop and went back to the Stone Age, according to the official government climate models it would be cooler in 2050 by about 0.015 degrees. But their models exaggerate 10-fold — in fact our sacrifices would make the planet in 2050 a mere 0.0015 degrees cooler! . . .

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1. The Medieval Warm Period, Recent Heating Spikes, and the Hockey Stick

The Medieval Warm Period, lasting from abut 900 A.D. to 1300 A.D., saw a significant jump in temperature to levels higher than today. For example, during the MWP, the British were growing grapes for wine along Hadrian's Wall, indicating that Britain at the time was hotter than it is today. The MWP occurred during a period when human contribution to carbon dioxide was negligible. Thus, if one accepts the reality of the Medieval Warm Period, then there is nothing unusual about increases in temperature we have supposedly seen in recent years. The theory of AGW loses its validity as there is nothing to distinguish it from natural cycles of heating and cooling that occurred in the absence of any human contribution to CO2 levels.

In 1990, the recently formed UN IPCC ran the following graph in their report. It shows both a robust MWP - hotter than today - and a Little Ice Age lasting through 1600 A.D., after which, in fits and starts, our climate is warming back up.



In the mid-1990's, the use of boreholes as a means to determine past climate history was validated, leading, in 1997 to an incredibly extensive worldwide study by Huang, et. al, the results of which are shown in the following graph:



The similarity to the UN IPCC's own 1990 graph is striking. But then, in 1997, Michael Mann published his hockey stick - a study that purported to do away with both the MWP and the Little Ice Age, writing them out of the historical record while making recent temperature increases appear to be without precedent.



To understand how Mann accomplished this amazing feat of erasure, the most understandable explanation comes from Ross McKitrick in his article, “What is the Hockey Stick Debate About?" It should be required reading for everyone debating AGW. In it, Mr. McKitrick itemizes the faulty math, the fundamentally flawed choice of proxy data Mann used to rewrite climate history, and Mann's stonewalling against making public disclosure of all his data, meta data, and computer programs that would allow scientists to verify his work.

Regardless, given Mann's Hockey Stick's utter centrality to the validity of AGW, the global warming crowd has stood by Mann's graph ever since - and indeed, replicated it with the now infamous Yamal Tree Ring study - a study based on possibly the worst case of cherry picking so far seen in AGW. Regardless, the hockey stick just got invalidated by Dr. Phil Jones in a BBC interview yesterday.

BBC: There is a debate over whether the Medieval Warm Period (MWP) was global or not. If it were to be conclusively shown that it was a global phenomenon, would you accept that this would undermine the premise that mean surface atmospheric temperatures during the latter part of the 20th Century were unprecedented?

Jones: There is much debate over whether the Medieval Warm Period was global in extent or not. The MWP is most clearly expressed in parts of North America, the North Atlantic and Europe and parts of Asia. For it to be global in extent the MWP would need to be seen clearly in more records from the tropical regions and the Southern Hemisphere. There are very few palaeoclimatic records for these latter two regions.

Of course, if the MWP was shown to be global in extent and as warm or warmer than today (based on an equivalent coverage over the NH and SH) then obviously the late-20th century warmth would not be unprecedented. . . .

Jones admits that the validity of AGW theory rests on proof that the MWP was not a worldwide phenomena. Then he puts the stake in the heart of the "unequivocal" and "settled" theory of AGW. Jones admits that the MWP is well documented in the Northern hemisphere and he claims that there is simply not enough data in the Southern Hemisphere to prove or disprove that the MWP was a worldwide phenomena. Mann's hockey stick - and Yamal, which purport to establish that the MWP did not occur or, in the alternative, was not global with finality, is dead. They are in fatal contradiction with Jones's pronouncements. At a minimum, this means that AGW is unproven.

But Jones goes beyond that. In his interview, he admitted that there have been similar warming spikes in just the past two centuries that are not any larger than the most recent spike through 1998:

Do you agree that according to the global temperature record used by the IPCC, the rates of global warming from 1860-1880, 1910-1940 and 1975-1998 were identical?

... Temperature data for the period 1860-1880 are more uncertain, because of sparser coverage, than for later periods in the 20th Century. The 1860-1880 period is also only 21 years in length. As for the two periods 1910-40 and 1975-1998 the warming rates are not statistically significantly different (see numbers below).

I have also included the trend over the period 1975 to 2009, which has a very similar trend to the period 1975-1998.

So, in answer to the question, the warming rates for all 4 periods are similar and not statistically significantly different from each other. . . .

This too would mean that there is nothing anomalous about our current warming. And, as Powerline notes, it is "completely at odds with the UN's 2007 IPCC report."

But going back to the MWP, the truth may be that there is in fact enough paleoclimatalogical data to establish the world-wide phenomena of the MWP. Unless someone challenges the validity of the borehole study, that would seem to provide sufficient evidence. But there have been many reports of recent vintage that also establish a robust MWP as a reality. Here is a graphic showing peer reviewed studies and their conclusions regarding the degree to which temperatures were higher (red) or lower (blue) during the MWP than they are today:

Adds CO2Science.org:

Was there a Medieval Warm Period? YES, according to data published by 804 individual scientists from 476 separate research institutions in 43 different countries ... and counting! . . . To access the entire Medieval Warm Period Project's database, click here.

But its not just the MWP that calls into question the validity of AGW. To the extent that climate can be traced back into the distant past, such as from unadjusted data derived from Greenland's ice core, it shows repeated periods of rapid warming and cooling and that we are in a prolonged period of global warming far predating the industrial period:.







2. Whether Modern Day Temperature Data Showing Global Warming Is Trustworthy?

One would think that measuring modern temperatures would be straightforward. The truth is that it is anything but. And indeed, this difficulty in agreement on a common measurement protocol coupled with manipulation of raw data to add "corrections" calls into question the validity of AGW every bit as much as the MWP.

As a threshold matter, no less a person than NASA's James Hansen explains in detail that there is no agreement on how to measure Surface Air Temperature(SAT), that temperatures measured at the same station can vary widely depending on the method used, and that SAT can change from the ground to just a few feet above ground. In other words, the precision claimed by the climate scientists in measuring temperature to tenths or hundredths of degrees over the entire globe is simply smoke and mirrors.

Things get no better when moving up to determining average regional and global temperatures. Two recently released studies, Surface Temperature Records: Policy Driven Deception? by meteorologists Joseph D’Aleo and Anthony Watts, and Surface Temperature Variations in East Africa and Possible Causes by John R. Christy et al, of Univ. of Alabama, both challenge the accuracy of modern global temperature records. The D'Aleo study goes through a litany of problems:

. . . The global surface-station data is seriously compromised. First, there is a major station dropout and increase in missing data in stations that remained which occurred suddenly around 1990; about the time the global warming issue was being elevated to importance in political and environmental circles. A clear bias was found towards removing cooler higher elevation, higher latitude, and rural stations during this culling process though leaving their data in the base periods from which ‘averages’ and anomalies are computed.

The data also suffers contamination by urbanization and other local factors such as land-use/land-cover changes and improper siting. There are uncertainties in ocean temperatures; no small issue, as oceans cover 71% of the earth's surface.
These factors all lead to significant uncertainty and a tendency for overestimation of century-scale temperature trends. A conclusion from all findings suggest that global data bases are seriously flawed and can no longer be trusted to assess climate trends or rankings or validate model forecasts. And, consequently, such surface data should be ignored for decision making.

One of the major facets to which D'Aleo refers is the so called "heat island" effect. Many of man's activities generate heat that, if picked up by a station, then shows a false warming. Rather than make an effort to resite the vast number of stations that today are subject to the heat island effect, entities that collect this data have applied "corrections." But as D'Aleo points out, "numerous peer-reviewed papers in recent years have shown the overstatement of observed longer term warming is 30-50% from heat-island contamination alone" and that "cherry-picking of observing sites combined with interpolation to vacant data grids may make heat-island bias greater than 50% of 20th-century warming."

And indeed, what corrections to apply for heat island effect in any particular instance is itself a very unsettled and controversial issue, with it appearing in many instances that the raw temperature data has been adjusted improperly to show warming where none exists. The story of the temperature station at Darwin Zero provides a particularly egrigous example.

The findings of Professor Christy are similar and were summed up in a Times article the other day:

“The temperature records cannot be relied on as indicators of global change,” said John Christy, professor of atmospheric science at the University of Alabama in Huntsville, a former lead author on the IPCC.

The doubts of Christy and a number of other researchers focus on the thousands of weather stations around the world, which have been used to collect temperature data over the past 150 years.

These stations, they believe, have been seriously compromised by factors such as urbanisation, changes in land use and, in many cases, being moved from site to site.

Christy has published research papers looking at these effects in three different regions: east Africa, and the American states of California and Alabama.

“The story is the same for each one,” he said. “The popular data sets show a lot of warming but the apparent temperature rise was actually caused by local factors affecting the weather stations, such as land development.”

So there is a real question the validity about surface temperature data. That is an independant basis that establishes that the supposed "unequivocal" and "settled" science of the AGW theory is anything but.

On a different issue, one of the points of contention has been whether there has been any warming shown in the past ten to fifteen years - a period that, if AGW theory was valid - should have shown temperatures increasing hand in glove with rises in man-made CO2 emissions. Responding to criticism in the wake of Climategate, the AGW cabal pushed the fiction - duly published by the Washington Post - that the world was still warming and that "nine of the world's hottest years occurred this decade."

This contradicts the UN's lead IPCC scientist, Kevin Trenberth, who, in an e-mail released as part of the CRU tranche, noted:

The fact is that we can't account for the lack of warming at the moment and it is a travesty that we can't.

Enter Phil Jones in the BBC interview with another bombshell admission, Jones "admitted that in the last 15 years there had been no ‘statistically significant’ warming . . ."

3. AGW & The UN IPCC's Climate Computer Models

The AGW movement has relied upon computer modeling to pose nightmare scenarios and drive policy. For example, it was in 2008 that, acting in response to a legal action brought by Center for Biological Diversity and other green organizations to have polar bears declared endangered under the Endangered Species Act, that the Bush Interior Dept. actually made such a finding. The head of the Interior Dept., Dirk Kempthorne, made his decision based on climate computer modeling showing that arctic sea ice, which even then was rebounding from its 2007 low, would disappear 45 years into the future due to AGW. He made this decision even though the polar bear population had exploded in the Arctic and was deemed at or near optimum levels.

Yet there is a problem. All of the computer models relied upon by the IPCC to posit AGW far into the future suffer a fatal flaw. All are built on the presumption that as more man-made carbon dioxide is pumped into the atmosphere, global temperatures will rise. And as the quotes from both Phil Jones and Kevin Trenberth in the above section prove, the world stopped warming in 1995. This means that AGW proponents have not established that there is a direct relationship between carbon dioxide emissions and temperature.

But the problems of the computer models go even beyond that, as explained by MIT Professor of Meterology Richard S. Lindz:

. . . The main statement publicized after the last IPCC Scientific Assessment two years ago was that it was likely that most of the warming since 1957 (a point of anomalous cold) was due to man. This claim was based on the weak argument that the current models used by the IPCC couldn't reproduce the warming from about 1978 to 1998 without some forcing, and that the only forcing that they could think of was man. Even this argument assumes that these models adequately deal with natural internal variability—that is, such naturally occurring cycles as El Nino, the Pacific Decadal Oscillation, the Atlantic Multidecadal Oscillation, etc.

Yet articles from major modeling centers acknowledged that the failure of these models to anticipate the absence of warming for the past dozen years was due to the failure of these models to account for this natural internal variability. Thus even the basis for the weak IPCC argument for anthropogenic climate change was shown to be false.

The fact that the IPCC's computer models did not anticipate and could not account for the current lack of warming is significant proof that the AGW theory is neither "unequivocal" nor "settled."

4. Peer Review, IPCC, Scientific Method and Climategate

The validity of AGW has been pushed on the oft repeated claim that all of the work of AGW proponents has been subject to the gold standard of reliability - peer review. But in light of Climategate - the scandal arising in the wake of the unauthorized release of a vast tranche of internal e-mails and other data from East Anglia University's Climate Research Unit - probably few things were so much called into question as the peer review process and the bastardization of the scientific method by AGW proponents.

For anything to be called science, others need to be able to access the raw data, the meta data, and the calculations or computer progams and then either verify or disprove the experiment. That is the "scientific method" as practiced across all sciences. But it stopped happening in climate science over a decade ago. What climate scientists began doing, beginning with Michael Mann's hockey stick graph in the late 1990's, was to refuse to provide the information necessary to reproduce their experiments. Indeed, it took over 7 years and literally an act of Congress to force Mann to post his data.

Probably no one has more experience with the repeated and continuous stonewalling by AGW scientists to every request for data than Climate Audit's Steve McIntyre. He has devoted an entire section of his blog to his litany of posts on this topic. You can find it here. The Climategate e-mails make crystal clear how determined the top level of climate scientists - Phil Jones, Michael Mann, etc. - were to keep their data and methods out of the public domain, even at the risk of violating the law of FOIA.

Dr. Judith Carter, the head of Earth Sciences at Georgia Tech, observed after reading the Climategate e-mails:

.. . . What has been noticeably absent so far in the ClimateGate discussion is a public reaffirmation by climate researchers of our basic research values: the rigors of the scientific method (including reproducibility), research integrity and ethics, open minds, and critical thinking. Under no circumstances should we ever sacrifice any of these values; the CRU emails, however, appear to violate them.

Dr. Carter added in a seperate essay that climate scientists needed to start acting like . . . real scientists:

Climate data needs to be publicly available and well documented. This includes metadata that explains how the data were treated and manipulated, what assumptions were made in assembling the data sets, and what data was omitted and why. This would seem to be an obvious and simple requirement, but the need for such transparency has only been voiced recently as the policy relevance of climate data has increased. The HADCRU surface climate dataset and the paleoclimate dataset that has gone into the various “hockeystick” analyses stand out as lacking such transparency. Much of the paleoclimate data and metadata has become available only because of continued public pressure from Steve McIntyre. Datasets that were processed and developed decades ago and that are now regarded as essential elements of the climate data record often contain elements whose raw data or metadata were not preserved (this appears to be the case with HADCRUT). The HADCRU surface climate dataset needs public documentation that details the time period and location of individual station measurements used in the data set, statistical adjustments to the data, how the data were analyzed to produce the climatology, and what measurements were omitted and why. If these data and metadata are unavailable, I would argue that the data set needs to be reprocessed.

There is no reason whatsoever that any of the climate science community should not, on all occaisions, act in accordance with Dr. Carter's advice. For a climate scientist to have to counsel others in her field on this issue gives some idea of just how far the AGW crowd has strayed from the practice of science. In the absence of this level of transparency and reproducability, there is not a single thing about AGW that can be called "unequivocal" or "settled."

The IPCC and AGW supporters attempt to sidestep this fundamental malfeasance by claiming that their experiments were verified by the peer review process. It is a neat trick - and amounts to asking the rest of the world to take their word - and the word of a few reviewers - on faith. That is not science, it's theology.

The IPCC and AGW crowd hold up peer review as the gold standard of reliability. But if the Climategate e-mails exposed anything, it was the degree to which the peer review process has been bastardized by climate scientists. This from Mark Steyn, summing up the situation:

The more frantically [the IPCC and AGW scientists] talked up "peer review" as the only legitimate basis for criticism, the more assiduously they turned the process into what James Lewis calls the Chicago machine politics of international science. The headline in the Wall Street Journal Europe is unimproveable: "How To Forge A Consensus." Pressuring publishers, firing editors, blacklisting scientists: That's "peer review," climate-style. The more their echo chamber shriveled, the more Mann and Jones insisted that they and only they represent the "peer-reviewed" "consensus." And gullible types like Ed Begley Jr. and Andrew Revkin of the New York Times fell for it hook, line and tree-ring.

The e-mails of "Andy" (as his CRU chums fondly know him) are especially pitiful. Confronted by serious questions from Stephen McIntyre, the dogged Ontario retiree whose "Climate Audit" Web site exposed the fraud of Dr. Mann's global-warming "hockey stick" graph, "Andy" writes to Dr. Mann to say not to worry, he's going to "cover" the story from a more oblique angle:

"I'm going to blog on this as it relates to the value of the peer review process and not on the merits of the mcintyre et al attacks.

"peer review, for all its imperfections, is where the herky-jerky process of knowledge building happens, would you agree?"

And, amazingly, Dr. Mann does!

"Re, your point at the end – you've taken the words out of my mouth."

And that's what Andrew Revkin did, week in, week out: He took the words out of Michael Mann's mouth and served them up to impressionable readers of the New York Times and opportunist politicians around the world champing at the bit to inaugurate a vast global regulatory body to confiscate trillions of dollars of your hard-earned wealth in the cause of "saving the planet" from an imaginary crisis concocted by a few dozen thuggish ideologues. If you fall for this after the revelations of the past week, you're as big a dupe as Begley or Revkin.

"Quis custodiet ipsos custodes?" wondered Juvenal: Who watches the watchmen? But the beauty of the climate-change tree-ring circus is that you never need to ask "Who peer-reviews the peer-reviewers?" Mann peer-reviewed Jones, and Jones peer-reviewed Mann, and anyone who questioned their theories got exiled to the unwarmed wastes of Siberia. The "consensus" warm-mongers could have declared it only counts as "peer-reviewed" if it's published in Peer-Reviewed Studies published by Mann & Jones Publishing Inc. (Peermate of the Month: Al Gore, reclining naked, draped in dead polar bear fur, on a melting ice floe), and Ed Begley Jr. and "Andy" Revkin would still have wandered out, glassy-eyed, into the streets droning "Peer-reviewed studies. Cannot question. Peer-reviewed studies. The science is settled."

This bastardization of the peer review process largely shut out both criticism of AGW and alternative theories. Thus is it any wonder that AGW proponents should claim, in true Orwellian fashion, a "scientific consensus" that the science of global warming is "unequivocable" and "settled" because there are no substantive body of peer reviewed studies to the contrary? It is a variant on the old saw about the boy who killed his parents then asked for mercy from the court because he was an orphan.

There is one last systemic issue on the peer review as it relates to climate science. Shannon Love has written an insightful article regarding peer review in the context of climate science where so much now relies on complex computer programs to arrive at finished data. Peer reviewers do not have the time to review the programs and, in any case, are never provided with them. This effectively negates any claim that peer review provides any standard for the reliability of the data and conclusions in the article. Ms. Love's solution is very practical:

Eric S. Raymond, the famous computer scientist and writer, has called for open source science. I think this is the way we should go. In the past, it cost too much to print out all a study’s data and records on paper and ship that paper all over the world. With the internet, we have no such limitations. All scientific studies should upon publication put online all of their raw data, all of their protocols, all of their procedures, all of their records and the code for all of their custom-written software. There is no practical reason anymore why only a summary of a scientist’s work should be made public.

Scientific software has grown too large and complex to be maintained and verified by a handful of individuals. Only by marshaling a scientific “Army of Davids” can we hope to verify the accuracy and precision of the software we are increasingly using to make major public decisions.

In the short term, we need to aggressively challenge those who assert that studies that use complex custom software have been “peer reviewed” in any meaningful way. In the long term, we have a lot of scientific work to do over again.

Summary

It is incumbant on those championing the theory of AGW to establish that the globe is warming in unprecedented fashion and that the cause of this warming is man via emissions of carbon dioxide. To this end, AGW proponents have written the Medieval Warm Period out of the historical record, relied on fundamentally untrustworthy Surface Air Temperature data, they have often refused to make public their data and methods and they have wholly corrupted the peer review process - all the while relying on peer review to stand in as a proxy for the scientific method as a means to establish the validity of AGW.

Between Climategate, the subsequent revelations by CRU head Phil Jones, and recent studies, it is apparent that the AGW crowd has not proven their theory. Dr. Jones admitted that the Medieval Warm Period existed in the northern hemisphere, and further admitted that, if it was shown to be global in scope, than it could well mean that our current warming trend is nothing more than a natural cycle of the earth. He also admitted that the MWP has not been contradicted, but merely that there is not enough data from the Southern Hemisphere to confirm or deny the MWP. This explodes the hockey stick graph which purported to show the MWP never occurred. Likewise, Jones admitted that the current rate of warming is not statistically different than in other warming spikes over the past 200 years. This contradicts the claim that our most recent spike in temperatures was itself anamolous.

The Surface Air Temperature (SAT) data, upon which the historical record rests since the advent of mechanical weather readings circa 1800, is not subject to any sort of precision in identification that would provide any confidence in the fine calculations being made in determining the historical data. Moreover, as two recent studies indicate, there are very fundamental flaws in our current system - from the vast decrease in monitoring stations over the past two decades to insufficient and improper manipulation of SAT data in light of the "heat island" effects. This also calls into question the accuracy of the AGW theory.

The IPCC's climate computer modeling shows a relationship between carbon dioxide emissions and rising temperatures. Each of the models fails to account for increasing levels of carbon dioxide, yet a plateau of temperatures since 1995. Thus the relationship between global warming and carbon dioxide is called directly into question.

Lastly, the AGW proponents have sufficiently bastardized the peer review process that it in no way can be considered an indicator of reliability for published reports, nor an indicator of unreliability for rejected reports attacking AGW or proposing alternative theories. In conjunction with the AGW scientists refusal to partake in the normal practice of the "scientific method," it means they have turned AGW from a "science" requiring reproducability into a theology requiring faith.

The sum of all this is that AGW, at a minimum and in all of its aspects, is unproven. Claims that the science of AGW is "unequivocal" and "settled" are ludicrous. Indeed, in many respects, there is no science even involved.

Update: Dana Milbank at the Washington Post writes:

Scientific arguments, too, are problematic. In a conference call arranged Thursday by the liberal Center for American Progress to refute the snow antics of Inhofe et al., the center's Joe Romm made the well-worn statements that "the overwhelming weight of the scientific literature" points to human-caused warming and that doubters "don't understand the science."

The science is overwhelming -- but not definitive. Romm's claim was inadvertently shot down by his partner on the call, the Weather Underground's Jeff Masters, who confessed that "there's a huge amount of natural variability in the climate system" and not enough years of measurements to know exactly what's going on. "Unfortunately we don't have that data so we are forced to make decisions based on inadequate data."

Kudos to Mr. Masters for something approaching intellectual honesty as to the state of AGW science.

Update: Robert Avrech of Seraphic Secret has been kind enough to link to this post. There is an interesting debate going on in the comments section of Robert's post with an AGW proponent who, among other things, finds fault with my/this post. Do feel free to click over and have a read.

Update: Heh.