K40 - Debunking Climate
Denialism
Junk “Science” and Other
Claims
Claim: There is no consensus among
climate scientists that global warming is
caused by human activities
• Why this Claim is wrong: Richard Lindzen is famous for this
misrepresentation, in front of Congress, and in public
pronouncements. More on him later.
• As data shows (next page) – the more deeply and actively informed
you are on climate research, the more convinced you are that global
warming is human-caused: 98%, and much higher than this if you
divide between quantities of scientific journal papers for/against
AGW instead of people themselves. (i.e. the ~half dozen “skeptics”
get very few papers published – those few papers get a massive
amount of “play” in the oil-financed media and blog-o-sphere
• AGW = Anthropogenic Global Warming – Useful Abbreviation for
this powerpoint!
Response to the survey question "Do you think human activity is a significant
contributing factor in changing mean global temperatures?" (Doran 2009) General
public data come from a 2008 Gallup poll.
It’s Only Gotten Worse for the
Denial Camp
And Worse…. Note the Pie “Slice” is Shown 5
Times Thicker than Actual, Just So You Can See
it At All
Now Down to 1, in an
Obscure Russian Journal
Claim: "32,000 of the World's Leading
Scientists" have signed a petition rejecting
the idea of anthropogenic global warming
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Why this Claim is Wrong: The quotation marks above stated by Bob Lutz, CEO of GM, in a wellremembered episode of "The Colbert Report". The infamous "Oregon Petition" arrived in the mail
of tens of thousands of people including some scientists (circulated in 1999 and again in 2007 and
signatures summed). It urged their signature rejecting AGW by using a paper by Robinson,
Robinson and Soon (RRS 2007) which is junk science at its most extreme.
A primary strategy of junk science promoters is to publish in outlets unable or unwilling to give
proper expert review. Note that RRS is published in the Journal of Physicians and Surgeons
(that's right - not a typo! To say the least, this medical journal is not known for having competent
climate science referees!). The petition is not filled with the signatures of scientists - its definition
of a scientist is: anyone who signed the petition (!) This is a petition whose layout only allows
check marks for PhD, MS, and BS degrees, and who admits they did not check the authenticity of
the signers. It's an oil and tobacco company sponsored petition carefully graphic designed to
appear to be a scientific journal article, and whose ultimate signatures include an unknown
number of real scientists.
Here is a site collecting numerous debunkings of this claim. Climate scientists at RealClimate
address the fraud. Only 39 of the 32,000 signers claim to be "climatologists", and by far the largest
category are holders of only a BS "or equivalent", in some subject or other (the lowest educational
check box option provided!). This "Climate Crock of the Week" video presentation covers the
background of those behind the signature campaign. It's not pretty. Here's a collection of errors
major and minor in the petition. In particular, this rebuttal by climate scientist Michael
MacCracken is the most detailed, requiring 23 tightly written pages just to enumerate the
distortions and falsehoods.
On the other side, the National Academy of Science (NAS) is made up of the most accomplished
scientists in the nation. Here is a letter signed by 250 NAS members condemning the attacks
by political forces on science in general and climate science in particular.
Another reason this is bogus – if you google “Richard Nolthenius”, you’ll find my name as
one of the signers of this Petition! Apparently they just harvested names of scientists off
the web or other public sources. Other scientists complain they too have been added w/o
their approval.
Claim: Water Vapor is vastly more important than CO2 in the greenhouse
effect. CO2 is a tiny component of the atmosphere and contributes only a
tiny amount of greenhouse warming. And besides, the absorption lines of
CO2 are saturated and so adding more CO2 to the atmosphere won't add
more greenhouse warming.
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Water vapor IS a bigger source of greenhouse warming than CO2 (although not by
much). But water vapor is not the initiating cause for the current rapid warming. The
reasons are many...
First, CO2 absorption lines are saturated only in the central core wavelength, adding
more CO2 adds opacity in the wings (wavelengths slightly different than the
theoretical wavelength of maximum absorption) of the absorption lines and traps
additional heat. Also, because of the saturated line core, detailed calculations show
that heat trapped only rises as the logarithm of CO2 rise (not linearly), in agreement
with observations. –
More important, there is always a height in the troposphere above which the absolute
density of CO2 is low enough that the absorption lines are not saturated. As CO2
levels continue to rise, the mean altitude where the bulk of the re-absorption of
outgoing IR radiation happens will slowly rise higher (but still far below the
stratosphere) - it certainly does not mean that heat trapped is constant with CO2
concentration. The saturated CO2 lines argument is just naive and false. If you'd like
a little more detail, this link describes the situation well, even for the spectroscopically
challenged. Here's another explanation of how bogus this argument is.
The increased warming due to CO2 is amplified by the resulting higher water vapor in
the atmosphere and its greenhouse effect, by roughly an equal amount, so the net
effect of CO2 greenhouse warming is doubled by adding in the increased water
vapor. In absolute terms, existing water vapor contributes 2.3 times more heating
than does existing CO2 (Keihl 1997)
Claim: “Scientific consensus is a sign of dogmatism, group-
think, unwillingness to consider other views, and is analagous to
religious zealotry. It is anti-scientific.”
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Why this claim is wrong: It’s more than wrong, it’s a slap in the face of science
itself. (see my page Denialist Claims online for more detail)
As a scientist myself, I find this claim deeply offensive, especially when it was
made by someone, in front of their students!, with no degree in science.
The fastest path to a stellar career in science is (#1) honoring a strict code of truthabove-all-else, and (#2) Find flaws in current thinking and develop better theories. In
that order!! As a scientist myself, for 30 years, and who has worked with scientists
all during this time, this is absolutely true..
Consider the absurdity of a massive conspiracy against young ambitious and bright
scientists to squelch the emerging truth about a phenomenon in order to maintain a
status-quo. While you can reasonably expect some resistance from less insightful
older die-hards, they cannot and do not stop progress, as is obviously demonstrable
when you look at the massive and rapidly accelerating advance of genuine scientific
knowledge.
There is too much advantage both personally, emotionally, financially, and in status,
for scientists to GET IT RIGHT.
The Heartland Institute published this editorial by Willie Soon and Sallie Baliunas,
from which this claim above seems to have been taken and rebroadcast by someone
who shall remain anonymous.
The Soon and Baliunus scandal, which resulted in the mass resignation of the
editors of the journal which published this junk science. Basically, the editors
acknowledged they were “asleep at the switch” and did not do their job in seeing that
this outrageously wrong paper got proper refereeing. Willie Soon was funded by the
American Petroleum Institute, and acknowledges receiving over $1 million.
The Scientific Publication Process
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A researcher puzzles over an explanation for a set of observations, comes up with an idea, and
tests it.
He and co-workers take the results and give invited talks at other research institutions, where
questions from fellow scientists can help refine their ideas
When they feel they’ve got a strong piece of work, they write it up and send it to a quality scientific
journal for publication (the better the journal, the better for their career)
The editor reads the abstract, quick once-over of the paper, and sends it on to 2 or 3 referees.
Referees are scientists whose area of expertise matches the subject of the paper.
The referees give their time, unpaid, to critically read the paper and carefully write up a referee’s
report which points out weaknesses and how to address them, or, if the paper is rock solid, an “all
clear” to the editor recommending publication. In some cases, the paper is so poor that the
recommendation is that the paper and the project needs to start over from scratch and it not be
published at all. But this is rare; usually the paper is worthwhile and just needs some extra work in
a few spots. Refereeing papers is viewed as a duty to science and your colleagues. Do it well, and
you can hope your referees will do good work refereeing YOUR papers.
The editor reads the referee reports, makes a judgment, usually following the referees and sends
it back to the authors for re-work.
The authors fix up the paper and resubmit, and it is published. If this is a prestigious journal (like
the Astrophysical Journal), editors are very careful to protect the reputation of the journal and junk
science almost never gets published.
Scientific Journals: journals from professional scientific organizations, supported by dues-paying
scientists. (e.g. the American Astronomical Society publishes several journals. I pay $150/yr as a
member of the AAS. These organizations have an interest in making sure they publish highquality science, and that includes ground-breaking new work which might significantly change the
direction of a field – not sticking with stale status quo.
This isn’t just a boiler plate advertisement. I’ve been a AAS member for 30 years, have had many
papers refereed, and been a referee on many quality papers by Harvard professors, etc. I do a
good job of refereeing, and referees have helped the quality of my own papers by their comments.
On the Other Side…
• …are trade journals. These are NOT proper scientific journals.
• These are “journals” published by corporate organizations.
• The papers here reflect what is in the interests of the corporations,
which may or may not have anything to do with good science
• “Energy and Environment” is the most notorious as far as
publishing nonsense about climate. “It is unclear whether E&E is
peer-reviewed. The journal is not listed by the ISI Web of
Knowledge, which provides "comprehensive coverage of the world's
most important and influential journals". E&E has been described by
climate scientist Gavin Schmidt as having “effectively dispensed
with substantive peer review for any papers that follow the editor's
political line”.
Claim: Fewer cosmic rays reach the lower atmosphere during
solar maximum, producing fewer low clouds because they act as
nucleation sites for cloud droplets, and fewer low clouds lead to
higher average ground temperatures (Svensmark 2007). This is
an amplifier for solar-caused warming of the Earth.
• Why this Claim is Wrong: Unlike most claims, this one is not
absurd on its face. I can imagine having a sense of excitement on
first considering this hypothesis and that it might be reasonable. It's
worth a careful look.
• Summary: High solar activity means a stronger solar magnetic field
permeating the solar system, which tends to deflect galactic cosmic
rays (very high speed ionizing atomic nuclei) from hitting the earth.
Galactic cosmic rays (GCRs) create charged particles which are
presumed to become cloud condensation nuclei (CCNs) from which
water droplets form, especially in the lower atmosphere. Thus, the
more GCRs the more clouds and vice versa. Higher solar activity
and hence fewer GCRs mean less clouds, reflecting less of the
sunlight, and more is absorbed at the surface. In other words, the
hypothesis claims - fewer GCRs -> fewer CCNs -> less low-level
cloudiness -> more sunlight absorbed by the Earth's surface ->
higher temperatures.
Neutron arrival rate, generated by cosmic ray showers, for the past 60 years.
Plotted with sunspot numbers; a good proxy for solar activity and global solar
magnetic field intensity. The correlation is strong and compelling. Cosmic rays
are correlated with the sunspot cycle
Change in cosmic ray intensity between 1700 and the present day
from four independent proxies. Intensities have been scaled to
the 13-GeV cosmic ray data from Huancayo, Hawaii, and then
normalized to the 1990–2001 mean.The plot shows deviations
from this mean. [from Carslaw et al. 2002]. Note that there is no
trend after the solar maximum of 1957, when the 20th century
solar cycle intensities peaked. The 11-year solar cycle appears
evident.
Global troposphere temps vs. cosmic ray flux. Note that before plotting
they have taken OUT a secular temperature trend of 0.14K rise per
decade - but this is the very temperature rise that argues FOR AGW!
So while there does appear to be a correlation here, it is a red herring
as far as being an argument against AGW. The short term temperature
correlation has a much simpler interpretation….
Svensmark's published correlation between cosmic ray
intensity and low cloud cover, shown here, includes satellite
calibrations disavowed by the actual scientists who designed
and operate the satellites
From Laut (2003), showing that Svensmark’s
apparent correlation between cloud cover and
cosmic ray flux breaks down after ~1995
Another study, by Bago and Butler (2000) in the
journal Astronomy and Geophysics, finds a similar
breakdown in correlation. Red is total cloud cover,
blue is low clouds, and black line is cosmic ray flux
from the Climax experiment
Can the ISCCP Cloud Data Even
be Considered Reliable?
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More important, the ISCPP satellite data on global cloud cover (used in
Svensmark's work) is known to be flawed (Evan et al. (2007) - authors and
abstract given below...
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"Arguments against a physical long-term trend in global ISCCP cloud
amounts": Evan AT (Evan, Amato T.), Heidinger AK (Heidinger, Andrew K.),
Vimont DJ (Vimont, Daniel J.), GEOPHYSICAL RESEARCH LETTERS
Volume: 34 Issue: 4 Article Number: L04701 Published: FEB 17 2007
Abstract: The International Satellite Cloud Climatology Project (ISCCP)
multi-decadal record of cloudiness exhibits a well-known global
decrease in cloud amounts. This downward trend has recently been
used to suggest widespread increases in surface solar heating,
decreases in planetary albedo, and deficiencies in global climate
models. Here we show that trends observed in the ISCCP data are
satellite viewing geometry artifacts and are not related to physical
changes in the atmosphere.”
So – the point is that it is CRUCIAL to be able to distinguish between
HIGH and LOW clouds, since these have opposite thermal effects on
the Earth, and the 2007 paper shows the data is NOT reliable
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• Bottom Line: “Our results suggest that in its current form, the
ISCCP data may not be appropriate for certain long-term global
studies, especially those focused on trends.''
• But, the problems with the cosmic ray idea get much worse…
There are already 1000 times more particles in the lower
troposphere which can grow into cloud condensation nuclei than
cosmic rays can provide. Cloud formation is NOT limited by
available particles!
• The cloud data itself is unfortunately not good enough to say much
of anything about Svensmark's hypothesis, except that there is no
support from the full data. There appear to be on-going problems
with calibrations, with the inability of the ISCCP to differentiate
between low, mid, and high clouds, view angle problems, and intrasatellite calibration problems. Since we're concerned with trends on
the decadal time scale, it may be some time before this particular
data is sorted out.
• While there probably is some correlation between cosmic rays and
global temperatures, the simplest and best supported explanation is
the already verified change in solar luminosity with solar cycle. Less
radiation causes cooler temps, and this solar-cycle effect overlaps
with Svensmark's unrelated and unsupported solar cycle hypothesis,
since more cosmic rays arrive when the solar cycle is a minimum.
• Other work quite clearly shows that cloud formation is far more
sensitive to other factors (99.9%) than to ionized particle availability
(0.1%) created by cosmic rays. I discussed this with a personal
friend who is also a leading professor of atmospheric science and
who develops computer models of cloud formation, and he agrees.
• But wait – there’s still more problems for Svensmark…
For ~60 years now, surface air temperatures have been climbing rapidly, while
cosmic ray flux and any cloud nucleation they might induce, have shown no net trend.
Conclusion - cosmic rays are no explanation for global warming
Alternatives to Human-Caused
Global Warming – Fail on
Examination
• 10 min video looking at alternative explanations
for global warming put forward early on by at
least a few scientists (vs. obvious
corporate/ideological shills), but which fail when
better data became available
• The video includes criticism of the cosmic ray
hypothesis, and more
Claim: It's the sun that is
causing global warming.
• Why this claim is wrong: A large number of studies all show that
the sun, whether by straightforward luminosity, or by UV flux, or by
modulating cosmic rays, cannot account for more than a tiny
fraction (if that) of global warming in the past 60 years.
• The sun's total luminosity does fluctuate slightly with the solar cycle,
as magnetic field energy thermalizes and emerges as luminosity.
However, it is weak, only 0.1% peak to trough. Since 1957, solar
cycle maxima have been decreasing in strength, and the same for
solar energy flux.
• And so too, all known variants of solar forcing show dimming or no
trend. Meanwhile, this period of time shows the most rapid and
accelerating global temperature rises, in lockstep with the rising and
accelerating GHG emissions due to man's activities.
• Here's a good article with graphs and summaries of many
published studies on the solar influence on climate.
So – who’s the culprit: the CO2 greenhouse effect, or the sun? Could there be some solar effect unrelated
to solar luminosity and solar magnetic fields which is at fault? Reality’s an open system, so cannot
rule that out based on this graph. But the burden of proof lies with anyone who wants to make such a
claim. Occam’s Razor says – it’s CO2 Greenhouse
Since 1977, Even better – Precise Satellite Data.
Temperatures Rising, Solar Irradiance, Not.
Claim: Wait! The Other Planets are
Warming too – this PROVES it’s The Sun!
• Denialists also claim that other planets are brightening and therefore
global warming must be due to the sun. While Neptune is indeed
getting brighter - it's been well shown for nearly 10 years that
this is a seasonal effect - "Neptune's nearly constant brightness at
low latitudes gives us confidence that what we are seeing is indeed
seasonal change, as those changes would be minimal near the
equator and most evident at high latitudes where the seasons tend
to be more pronounced." (Remember too, that Neptune's seasons
last 164 times longer than ours!).
• All outer planets have seasonal cycles that last from one to many
decades - much longer than the one year for the Earth, or period of
good data. The planet data is sparse for photometry at that subtle
level, and consistent with all being seasonal effects, and not due to
secular changes in the sun's energy.
• In fact, you can see that several measures of solar luminosity show
only the solar cycle effect, and that the secular trend is actually
slightly down, if anything (graph next page)
Claim: Global Warming is a Scam, Cooked up by
Climate Scientists to Pump up Their Research
Grants
• Really? - A global conspiracy by thousands of researchers falsifying
data, arm-twisting every new grad student and post-doc into the
conspiracy, against the motivations of their own career (let alone their
integrity)? Really?? Remember, there are thousands of professional
climate scientists out there, and as many doctoral students and postdocs.
• A scientist’s career is boosted hugely by showing he is #1 Honest, and
#2 Can devise new theories which overturn a field and yet satisfy solid
observations. There is powerful career and financial motivation to
NOT be a member of the consensus – UNLESS the CONSENSUS
is CORRECT!
• The most charitable thing I can say is – this is made by corporatepaid people who show us every day that they consider sacrificing
their integrity as just another cost of doing business; and they
project this dishonesty on scientists with their gray-colored glasses
• On “it’s the sun, not humans!” claim; They provide no evidence, nor
even any believable rationale, for this claim, only slander. By this kind
of greedy logic, who would have more incentive than the Stanford
Solar Center (where I worked for a time as a PhD student) to implicate
the sun in global warming? Yet, see what they have to say here.
Claim: CO2 is Good for Plants, and
More CO2 is Good for the Earth
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Why this Claim is Wrong: This is another claim which only sounds
plausible to a science-ignorant public (who are the target, of course).
While CO2 is used by plants to make their own biomass, it is misleading to
then try and sell the notion that human-caused rapid injection of CO2 into
the atmosphere will be good for plant life. It is not true that today's rising
CO2 levels are helping plants. Quite the contrary. CO2-induced climate
change is stressing plants more than helping them.
Agricultural scientists are pointing out that rising night-time temperatures, a
signature of greenhouse gas-induced warming, are reducing crop yields in
the major breadbaskets of the world, as well as stresses on animals grown
for agriculture - see the testimony of agricultural scientist Dr. J. Hatfield
in front of Congress.
A new study, published in Nature - Climate Change and announced by the
National Science Foundation, shows that after a short, initial growth spurt
when CO2 levels rise, plants then become stunted.
• Climate
zones are
changing
rapidly due to
warming, too
rapidly for
plants to
easily adapt
to.
There Are Exceptions…
• Especially one known plant which does
indeed do much better under an enhanced
CO2 Atmosphere…
• …Poison Oak/Poison Ivy (which becomes
SuperPoison Ivy of the future, as termed
here)
• Bottom Line: If you like poison oak,
you’ll love the future…
Claim: Global warming has stopped
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since 1998
Why this claim is wrong: The notorious Richard Lindzen is the originator of
this one, and later echoed endlessly in the denialist blogosphere in many
places. In fact, as best summed up here in this article – it’s "cherry picking"!
This claim is extreme cherry- picking. Choosing 2012 back to 1998 is the
longest period you can get away with and still just barely fail the standard
measure (95% confidence interval) of statistical significance, due to the
shortness of the interval(!)
The disingenuousness of it all is discussed here.
There are several effects which combined to lower the rate of surface
warming, counteracting the accelerating CO2 concentrations…
1. The Pacific Decadal Oscillation headed into a cooling phase in 1998
2. Low-level volcanism is now seen to contribute to global cooling more
than had been thought, especially over this interval
3. The sun has been getting less luminous
4. Rising coal-fired power plant sulfate aerosols, mostly from rapidly
growing Asia, are likely adding to cooling.
5. The favorite temperature records quoted by the climate denialists is
the HadCRUT3 and related datasets, which make no correction for the
fact that polar weather stations are missing from the data, yet we know
the poles are warming at least twice as fast as elsewhere.
When corrected for all these, there is NO CHANGE in the rate of warming!
Taking out Volcanos, Solar Variation,
and PDO Effect, There’s No “Great
Pause” After All.
Claim: Cloud feedbacks from enhanced warming are
negative (i.e. cause a net cooling), so that climate
is essentially stable.
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Why this claim is wrong: This is Richard Lindzen's "Iris Effect" hypothesis, proposed in 1990.
His claimed is that higher water vapor in the warmed atmosphere rains out lower in the
atmosphere, leading to fewer cirrus clouds (stratospheric cirrus clouds have a net heating effect
by blocking outgoing IR radiation). The evidence and theory both point to cloud feedbacks actually
trending towards increased warming, i.e a positive feedback. Observations show that increasing
sea surface temperatures correlate with a decrease in "anvil" clouds and deep convective clouds.
The question is, do these clouds heat, or cool the atmosphere?
Brian Soden, a Princeton climate scientist, examined the tropical greenhouse effect in and out of
El Nino conditions and finds that clouds behavior is opposite to that hypothesized by Lindzen
(Soden 1997). And Lin (2002) finds "The observations show that the clouds have much higher
albedos and moderately larger longwave fluxes than those assumed by Lindzen et al. As a result,
decreases in these clouds would cause a significant but weak positive feedback to the climate
system, instead of providing a strong negative feedback, opposite to Lindzen's hypothesis." This
recent study again shows cloud feedback is positive (more CO2 warming leads to more cloudcover induced warming), not negative. See more studies backing up this conclusion here and
here, and Dessler (2011).
The current incarnation of Lindzen's idea is in Lindzen and Choi (2009), claiming that the ERBE
satellite data show increased outgoing radiation from Earth to space when sea surface
temperatures rise. But this work has a number of major flaws which are fatal to the hypothesis,
pointed out by Trenberth et.al. here. (The journal paper is here).
Lindzen is reportedly reworking his claims yet again. Given his original incarnation was published
now over 20 years ago, it seems like variants are going to be keep coming, regardless of how
embarrassingly wrong they continue to be.
Lindzen's ideas are quite outside what both theory and observations demonstrate. More
disturbing, these studies above show Lindzen cherry-picking his time interval, cherrypicking his model heat flow parameters, and a deeply flawed portrayal of the relation of the
tropical system to global climate (see in particular the Dessler (2011) study of tropical
air/ocean/clouds study).
Update: 2012 on Lindzen’s Deeply
Flawed Papers
• A 2012 New York Times newspaper article on Lindzen
and clouds is a good read for the layman (refreshingly
so! Imagine - a newspaper!). In it, Lindzen finally
acknowledges "embarassing" and "stupid mistakes" he
made in Lindzen and Choi 2009. But the bad science
continues - Lindzen's re-worked Lindzen and Choi
(2011), is just as deeply flawed as the earlier
incarnations…
• Submitted to an obscure Korean journal after being
rejected by the Proceedings of the National
Academy of Sciences, reviewers noted that the paper
is based on "fundamentally flawed assumptions about
global climate sensitivity". A detailing of the flaws is
here.
• This seems to be the twilight of the Lindzen story. He
seems to be out of the limelight in the past few years
In Fact, Cloud Feedbacks So Far
Seem to be Positive, Not
Negative
• Sherwood et al. 2014 show that the
surface convective zone deepens under a
warming climate, reducing the low clouds
which cool climate
• Dessler (2010) also finds a positive
feedback, confirmed by Zhou et al. (2013)
From Dessler
(2010),
Surface
temperature is
positively
correlated
with radiance
from clouds
Claim: Climate
scientist Michael Mann (of Penn State University) is
guilty of misusing confidential data, engaged in a conspiracy to withhold
information, and manipulated or destroyed data to strengthen his case
that human activity was changing the global climate.
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Why this claim is wrong: Michael Mann is principal author of the famous 1999 paper which first showed the
"hockey stick" graph of global temperature for the past one thousand years, ending in the upward "hockey
blade" spike during the fossil fuel age. This was a centerpiece in Al Gore's "An Inconvenient Truth"
It is natural that AGW denialists would go after the author of this work. These charges against Michael Mann are
serious, enough to terminate a career if found true. One would hope the AGW denialists had evidence before
making and distributing to the press such charges. In fact, the slander revolves around the meaning of the word
"trick", found in emails stolen by the AGW denialists ("Climategate").
Scientists and mathematicians often use the word "trick" to refer to a clever insight used to solve a difficult
problem. As a scientist who hangs around other scientists, I can tell you this is absolutely true. Anyone who would
base such serious slander on their ignorance of the meaning of the word "trick" clearly has no experience in
science or mathematics (or perhaps they knew exactly what it meant, but yet found this a great opportunity to
advance their agenda by making such slanderous charges in front of policitians and science-ignorant students,
media, and the public).
Having on your faculty a prominent scientist guilty of fraud and other misconduct would be a huge liability, and so
even if the charges had no basis or evidence, Penn State University conducted an inquiry - and Mann was cleared
of any wrong doing or bias. Here's the NY Times article on the inquiry and Mann's vindication, with embedded
links. Note also that AGW denialist blogs charged him with witholding data and hiding or destroying data. This
inquiry and a dozen others found NO BASIS for this charge.
All data and codes legally able to be released were released at the time of his original paper. All data and
codes subsequently were cleared by foreign countries to release, and have been released. It was those
other countries whose data partially comprised the dataset analyzed. See this recent interview in
"Discover" magazine. All relevant climate forcing data is available to anyone, here. Here is Mann's response to
the political witch hunt against climate scientists, including himself. And a more recent response (Dec 2011) by
Mann is here. I have personally heard these baseless charges against an honorable scientist made by
someone quite close. Anyone who would repeat such slanderous charges - worst of all, to students, as if
they were fact, as late as 2009, when they in fact have no basis, let alone provide any proof... what can
you say about their own bias, their own objectivity, their own committment to telling the Truth?
Outrageous slanders against Michael Mann aside, how do the data-based criticisms of the "Hockey Stick"
temperature plot stand up? Here's an excellent study showing re-analyses even assuming the (mostly invalid)
criticisms of the 1999 analysis. Bottom line: no significant change - it's still a temperature "Hockey Stick".
“Climategate”
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"Climategate" was a fabricated smear campaign against climate scientists,
based on stolen emails from the correspondence between climate
scientists, and timed to be released to the media shortly before the 2009 UN
Copenhagen Climate Summit, no doubt to insure that no significant
carbon taxes or other other carbon-limiting agreements would result.
Denialists took naive or distorted meanings from out-of-context passages to
appear to justify their charges in the media that global warming was a
scientific fraud. Numerous investigations showed there was no fraud, no
bad science, and no lies. Out of thousands of private emails, THIS is
the best case they could make for conspiracy and fraud?.....“trick” is
an honored word in scientists jargon, to mean a clever (and proper)
way to get around a difficult problem. “Hide the decline” was referring
not to decline in ACTUAL temperatures, but in the tree-ring proxy data,
which clearly stopped working as a temperature proxy by the mid 20th
century (probably because CO2 was now so far out of the typical
range of the past 1000 years of calibration data, and tree ring width
would be expected to correlate to not just temperature but CO2 as
well.
The real fraud is the behavior of AGW denialists who so easily slander the
work and character of good scientists in the name of preserving "business
as usual" corporate profits.
The current (late 2011) state of this attack on climate scientists is well
linked and summarized here.
ALL raw temperature data used in these many analyses (except some from
Poland) are available to anyone, including you!
Does this look like a slow rebound from the last great Ice Age 12,000 years ago, or
the Little Ice Age which ended around 1850? Temperatures before the
Industrial Age were consistent with a slow cooling, in the same direction as the
Milankovich orbital forcings discussed in the PaleoClimate lecture. When fossil
fuels became an important input to the atmosphere, only THEN did temperatures
start heading up.
Regarding the Little Ice Age and Solar
Activity
•
There is little doubt European temperatures were lower for a few hundred
years centered around the year 1600. ~30 years ago it had been assumed
by many that the Maunder Minimum in solar activity may have caused the
Little Ice Age. However that was only a tentative assumption in the early
’80’s (Eddy et al.) as we had no precision data on solar output vs solar
activity until the mid ’80’s onward.
• We now have good satellite data on insolation over the last several solar
cycles, and the insolation only varies by less than 0.1% maximum to
minimum in the solar cycle, so that a prolonged period of low solar
activity such as the Maunder Minimum would not correspond to low
enough solar heating to account for the Little Ice Age. This is confirmed
by a recent paper by Feulner and Rahmstorf (2010) , (GRL paper here).
• Instead, studies show that during the Little Ice Age…
---- There were stronger and more frequent volcanic eruptions, which put
sulfate aerosols into the atmosphere and cooled the Earth by reflecting
sunlight. Volcanic eruptions provide the best fit to the climate data regarding
the Little Ice Age (Robock 1979) Note this has been known for over 30
years now!!
----the Black Plague and Columbian disease epidemics spread to the New
World caused a large (20%) drop in total human population during the late
middle ages, leading to cleared land undergoing reforestation which took up
enough carbon to account for the 10 ppm of observed drop in CO2 levels
associated with the Little Ice Age. This brief reference is interesting,
though not a peer-reviewed paper.
Claim: Why should we believe climate
scientists now? In the '70's they were
predicting we were headed for an Ice Age!
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Why this claim is wrong: In fact, a look at the scientific literature from
1965 to 1979 finds only 7 papers warning of imminent cooling, compared to
44 warning of Global warming (Peterson et.al. 2008), or 14%
Here's an entertaining and informative YouTube video summarizing the
history of our understanding about climate change over the past 120
years, including just how many climate science journal articles supported
the idea of an imminent cooling in the '70s (very few). Also, the original
CAUSE of the concern for cooling was the levelling off of 20th century
global warming during the 1940-'70 period, which we now know was due to
the cooling effect of rapidly rising air pollution caused by the industrialization
of the post-WWII world, and a cooling phase of the Pacific Decadal
Oscillation, at a time when CO2 emissions were far below what they are
today.
Recall too that in the late '60's and early '70's computers were very primitive
and climate modelling was similarly primitive. Even so, many climate
scientists were predicting, even before temperatures resumed upward
trends in the '70's, that CO2 greenhouse effect warming would soon
overwhelm pollution effects and take over with a vengence (see here). Also,
American Institute of Physics: publication on the history of the
science of CO2 and climate.
Claim: Greenland is actually gaining ice, not losing it, as global
warming alarmists would have you believe ”The evidence so far
suggests that the Greenland ice sheet is actually growing on
average" - Richard Lindzen, quoted here
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Why this claim is wrong: Cherry-picking, basically is the answer. The cold high altitude interior of Greenland did
have a net gain of snow during the '90's, but this was found to be consistent with global warming models, which
include higher evaporation of warmer ocean water and deposition as snow at the very high elevations of the top of
the Greenland ice cap, which was then still cold enough to have the net snow balance be positive. However, the
ERS-1 and ERS-2 satellite data used was not able to say much about the behavior of ice near the coastal areas,
where in fact ice has been melting and sliding into the ocean at an accelerating rate. Satellite data using
gravity measurements show that the entire continent is net losing ice. (this YouTube shows how GRACE
works).
Note that the rate at which the ice is disappearing has doubled in just this last decade - a decade during
which the solar heating contribution has actually been dropping as we've gone from a solar maximum in 2001 to
an unusually deep solar minimum in 2008/9. Ice loss is also happening in Antarctica (and here). A major factor
is that the speed of Greenland glaciers is rising rapidly. Meltwater on the surface is observed to follow
channels down to the base of the glacier, lubricating its gravity-induced motion towards the ocean. Without
detailed images of the base of glaciers, it was difficult to model this with any confidence and so to be conservative,
the IPCC decided to not include this aspect in their AR4 report. Unfortunately, the result is a significant underappreciation of the loss of continental ice at the poles due to global warming. To address this, Vermeer and
Rahmstorff (2009) have devised a semi-analytic method which captures 98% of the variance in ice volume vs
global temperatures, and use it to predict sea-level rises for the coming century using current and historical data. It
shows sea-level rise of 3-6 feet by 2100 (depending on anthropogenic emission scenario), which is 3 times the
IPCC AR4's conservative calculation (see 3rd panel graph below). Baffin Island, also in the Arctic and the 5th
largest island on Earth, has lost 50% of its ice cap in the last 50 years. Globally, glaciers worldwide are in rapid
retreat (see graph below right - sorry for the poor reproduction!). See this video of congressional testimony which
contains a nice animation of the GRACE data on where and when ice is being gained and lost on Greenland.
This 2011 paper in GRL shows excellent agreement between two ice volume measures: GRACE, and ice
accumulation vs perimeter loss. They both show accelerating ice loss and strong rising sea level predictions for
this century. However, a new paper published in Nature (Sundal etal 2011) uses satellite measurements to show
that once a critical level of melting is exceeded, the drainage under glaciers transitions to a more efficient mode
and glacier speed slows. It will be interesting to see this new work included in future modelling of Greenland ice
loss, as it is the major determiner of sealevel rise as global warming accelerates.
The latest study, published in Nature: Climate Change in 2012, shows indeed that Greenland is more
sensitive to losing it's entire ice cap than previously thought. We are already close to the temperature levels
which, if sustained, will completely melt Greenland over the next centuries or millenia, even if CO2 levels are
brought back down.
Claim: "How can you trust climate models, they don't even
include clouds!“ and “Aerosols aren’t even considered!”
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Why these Claims are Wrong: Note quotation marks – Climate models have included clouds for
decades. It's a gross misrepresentation. As just one example from several years ago, see Hansen et.al.
2005, which includes both low and high level clouds in its climate modelling. That said, cloud modelling has
been difficult and has been done by parameterizations based on observations. This is a good approach
when the complex physics doesn't have sufficiently known boundary conditions or numerical resolution to
model directly from first principles. It does not mean that the models are nonsense in what they produce.
The evidence shows otherwise. Clouds are important to get right since about half of all insolation reflected
back out to space is reflected by clouds. The IPCC AR4 identifies cloud modelling as one of the main
contributers to the remaining spread in future temperature trends. But that spread is minor compared to the
magnitude of the predictions, which are - severe warming.
The situation has improved substantially in 2006 with the advent of the "A-Train" satellites observing
coherently the same wide regions from space across a wide range of wavelengths in order to measure
simultaneously aerosol content, spectroscopic identification of components, albedo, and droplet sizes from
reflection properties.
Published results show the pollution aerosols make for smaller water droplets and ice crystals and less
rainfall from those clouds (Jiang et.al. GRL 35, L14804 (2008)). We've confirmed also what we've known
since 1989; that large concentrations of sulfate aerosols (e.g. from fossil fuel burning) lead to smaller water
droplets and brighter clouds (given the same water content), and that the smaller droplets inhibit
precipitation and lead to longer lived clouds. So pollution adds a net cooling, on average. Since the
industrialization of Asia has significantly net added to aerosols world wide, we expect a net cooling from
this effect, yet clearly global temperature continue to rise despite this.
Cloud feedbacks appear to be a positive feedback, meaning that CO2-induced warming alters cloud
properties so that they accentuate the warming further. According to a study by Clement et.al. (2009)
studying 55 years of COADS cloud data in the southeast Pacific, rising sea surface temperatures cause a
decrease in low clouds and a further increase in low level temperatures
The UK Met office's HADGem1 climate model closely matched the behavior of low clouds very well, and
also is showing positive feedback. And finally, this paper (Dessler 2011) appeared recently, showing
fatal flaws in the claims of Spencer and Lindzen that cloud cover changes are causing global warming, and
that models, observations and theory all agree well when done self-consistently. The cloud modelling
uncertainties are nowhere near large enough to change the important conclusion - that man-made GHG's
are causing the observed global warming.
Claim: "CO2 Follows Temperature, Not the
Other Way Around"
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Why this Claim is Shamefully Misleading: This was the most stunningly naive claim of all
(or deliberate red herring). Look at the logic this claim attempts to persuade with: Because
many past instances in the paleoclimate record show temperatures rising from low levels,
followed hundreds of years later with rising CO2 levels, this means that current CO2 rise
cannot be causing global warming today. If your response is puzzlement and a struggle to
grasp the logic, be reassured - there is no logic to grasp.
This claim is a deliberate association of Ice Age causation with today’s climate change –
when the two causes are obviously quite different. When temperature rises due to orbital
change, the rising ocean temperature brings more CO2 out of solution and into the
atmosphere (Callion et.al. 2003). The increased CO2 in the atmosphere then causes further
temperature rise by the greenhouse Effect, which induces more CO2 out of the ocean, etc.
This positive feedback, together with the ice albedo positive feedback effect, is sufficient to
bring Earth out of an Ice Age into an interglacial. It takes many centuries for this process to
happen as the CO2 transfers into and out of the ocean are quite slow because global deep
ocean currents are very slow, and because the process proceeds through stages of quasiequilibrium. (see here, and here.
Today's global warming is happening not on the thousands of years time scales of the "CO2
Follows Temperature, Not the Other Way Around" cannard, but a few decades. And the
record clearly shows CO2 rise is happening followed closely by temperature rises. The
reason is simple - we're adding CO2 directly to the atmosphere, at a pace far in excess of
what the ocean or land can absorb. Not even remotely in equilibrium.
It's not at all like "CO2 follows temperature" examples in the pre-human record. 10,000 years
ago, humans comprised about 0.1% of the land vertebrate biomass. Today, we comprise
over 99%, and drastically altering the atmosphere as we dominate the planet.
Claim: Cities have grown during the 20th century and their
asphalt, concrete and buildings absorb much more heat than
vegetated countryside. This biases temperature measurements this "Urban Heat Island Effect" accounts for much or all of
global warming, not CO2.
• Why This Claim is Wrong: This effect is and has been very well
understood and continues to be factored into studies of global
temperatures. The denialist claim is disingenuous in the extreme
and aims itself at the naive, who don't realize how obvious and for
how long this effect has been understood by climate scientists.
• For example, the latest IPCC report in 2007 finds that urban heat
island effects have been determined to have negligible influence
(less than 0.0006 °C per decade over land and zero over oceans) on
these measurements. Fox News TV weatherman Anthony Watts is
obsessed with this “explanation” of global warming.
• There isn't, and never was, a "urban heat island" issue with the data.
Here's the latest graph showing global temperatures using all data,
and using only rural weather stations. For the entire 160 year period,
there is no difference (with the exception of the Civil Warquestionable data-taking in the heat of battle?) .
As if urban thermometers were the only
evidence of a warming world!!
Warming World Evidence Far More
Than Just Weather Station Data
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Snow cover is dropping
Glacier area and thickness is dropping rapidly
Tree lines shifting pole-ward and upward in elevation
Sea ice breaking up and ice coverage area dropping at
both poles
• Atmospheric absolute humidity rising
• Even the birds, bees, flowers and trees, are all
responding by migrating their habitats (if they can) in a
way consistent with a warming planet – poleward and
higher in elevation to keep to their necessary
temperature zones
• There IS, of course, ONE OTHER EXPLANATION…
They’re IN on it!
• The Massive Global Conspiracy to Hide
Data, Defraud You and Me, and complete
the Communist One-World Hedgemony!!
• The Birds! The Bees! The Flowers!
And The Trees!!
• They’re ALL…. IN….. !!
If there’s a Conspiracy, it’s on
the Climate Denial Side…
Claim: Climate scientists who claim global warming
will be a disaster are just alarmists trying to scare
you for their own unsavory purposes
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Why This Claim is Wrong : Richard Lindzen is fond of repeating this theme (while
supplying no evidence) - that climate scientists are just trying to scare you, for their
own nefarious purposes.
Let's consider whether the predictions from the IPCC consensus documents are
"alarmist" or not. This link concisely compares the IPCC AR3 (2001) and AR4
(2007) predictions with actual observations since publication. It shows CO2
emissions accelerating upward even faster than the most "alarmist" IPCC scenario, it
shows sea level rising at a rate at the extreme upper end of the range of IPCC
scenarios since 1990, and it shows arctic ice loss accelerating faster than even the
most alarming IPCC AR4 models.
Even the more recent IPCC AR4 issued in 2007 is actually too conservative and not
"alarmist" enough in its predictions. The AR4 predicted that the Arctic would not
become ice free in summer until near the end of the 21st century, but it did not
include modelling the effects of breakage and movement of broken ice. Moving ice
finds its way into the ocean currents that carry it out of the Arctic Ocean, where it
melts rapidly (Rampal et.al 2011).
It is not only the area of ice loss, but the thickness of the ice that does remain which
is thinning rapidly, so the ice volume is shrinking even more rapidly. This MIT
University study (2011) shows far more rapid ice loss predicted for the Arctic
Ocean, and an ice-free Arctic is likely to happen by mid-century. Elsewhere here, I
reference observations of ice loss due to glacier movement in Greenland, significantly
worse than IPCC predictions because they were unable to model the glacier
base/ground interface and so did not include it, yet observations clearly show that
glacier movement is accelerating as the Earth warms, faster than the IPCC
predictions.
CO2 Emissions are exceeding even the most alarming
scenarios of the IPCC AR3
Seas are rising (blue) at the extreme upper edge
of IPCC projections (gray)
The IPCC AR4 2007 modelling of glaciers did not include the
effect of meltwater on lubricating glacier/soil interface. When
real-world data is used to include this effect… it’s much worse
still (upper curves) (Rahmstorff et al.)
On Richard Lindzen
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Richard Lindzen is the highest profile and considered the most prestigious (Sloan fellow at MIT) of
the AGW denialists. So it's disturbing that he uses his MIT position (earned by reputable work that
was not AGW-denialist oriented way back when he was a young man) while making
misrepresentations in the Wall Street Journal and other non-science journal outlets about climate
science and the scientific evidence for global warming, without references, without support. Here
is an account of his testimony in front of the UK's House of Lords and the outright falsehoods
about the scientific consensus. A quote from this article: "when a panelist specifically asks ‘how
far your view of the role of water vapour is shared by other scientists?’ (Q144), one cannot
honestly answer ‘That is shared universally’ when no other scientist in the field has made a
case for a negative water vapour feedback. This is probably the most egregious mis-statement in
the whole testimony and is deeply misleading."
Here are links to his conflicts of interest in taking money from Big Oil, and to his own grad
students' testifying that Lindzen feels a strong emotional need to prove his status at the expense
of others, bringing into further question his ability to be objective and truth-oriented: “If you want to
prove yourself a brilliant scientist, you don’t always agree with the consensus,” said Daniel KirkDavidoff, a former student of Lindzen’s at MIT. “You show you’re right and everyone else is wrong.
He certainly enjoys showing he’s right and everyone else is wrong,” Kirk-Davidoff continued. “If
you have a ten minute conversation with him, you can tell that.”
Response to Lindzen's Newsweek interview
Here's another good video on the junk science of the objections to AGW, the final few minutes
of which does a good summary of the poor science in Lindzen's "Iris" hypothesis.
A long and growing list of Lindzen quotes and comparisons with reality, is here. No responsible
person sincerely desiring to know the truth can afford to simply take his unsupported
pronoucements and poor science on faith, just because he's an MIT professor. That is the classic
logical fallacy of "the argument from authority".
Update 2012: Despite having been called on his outrageously wrong statements time and again,
he continues to make them - oblivious to answering those who point out how obvious are his
errors. The latest in this long line of dis-informational talks is described here, and here. Lindzen
has another (Aug 22, 2012) op/ed piece in the Wall Street Journal which continues to spread
misinformation which is at odds with the evidence, as critically examined here.
Key Ideas: Debunking Denialist Claims
• Popular denialist claims:
--- “It’s the Sun” (no, for past 60 years solar luminosity constant)
---“Urban heat island effect” (shows actually no effect on temperatures, and was
understood in original papers anyway)
---”It’s a conspiracy!” (career motivation of scientists is NOT to tow the part line,
but champion truth ESPECIALLY if it goes against consensus. Motivational
logic is all wrong. Conspiracy much more motivationally aligned with climate
denialism, not scientists)
--- There is powerful career and financial motivation even for a good scientist, to
NOT be a member of the consensus – UNLESS the CONSENSUS is CORRECT!
---”IPCC is alarmist!” (their early e.g. 1995 and 2001 and even 2007 AR’s are in fact
showing to be far too mild [sea level, glacier melt, Arctic ocean ice loss, etc]
vs. subsequent data. And motivations of parent governments of individual
scientists is to force it to be milder, since scientists predominately come from
biggest CO2 emitting countries)
--- “Cosmic Rays cause low clouds, cooling climate. Lessening cosmic rays could
be causing Global Warming”. No. No evidence CR’s nucleate any clouds, 1000x
more CCN’s already so don’t need CR’s anyway. And CR’s have NOT increased
or decreased over past 60 years.
--- “GW is just a rebound from last Ice Age, or the Little Ice Age”. No, temperatures
were very slowly cooling right up to the sharp change to warming at beginning
of 20th century. All of the rising of temps from end of last great Ice Age were
obviously done by 8,000 years ago.
--- Trade journals published by corporate organizations, and clearly for corporate
purposes. Genuine science journals published by scientific societies,
supported by dues-paying scientists. Trade journals like “Energy and
Environment” have a very poor reputation of publishing unbiased science.