A couple of items for those interested:
First, a critique by Prof. Judith Curry of the models used to predict
climate temperatures and trends.
For those who haven't heard of her, see
Second, an article on Watts Up With That, initially querying where the
heat comes from that has caused the recent El Niño event, and earlier
ones, but extending to offer yet another alternative explanation for
Global Warming, that is claimed to fit the existing data much better
than does simple anthropogenic CO2.
Who Mike Jonas is, and what his qualifications are to write such an
article, I've no idea, although Googling for him suggests he
contributes regularly to WUWT and Curry's blog.
I see you still fighting the same old strawman.
Climate models are not certain. Predicting the climate is not the same
type of science as building a bridge or power station.
The sensible discussion is about risk and expectation.
The scientific analogy that should be used is that of medicine. New
medicines should not be used without testing. History teaches us that
unexpected and catastrophic negative consequences can occur.
All the climate scientists are really telling us is that they are pretty
sure that we are now significantly affecting the climate and that we
should try to minimise those effects because we do not fully understand
what this "medicine" will do.
In short our uncertainty should lead us to stop emitting CO2 rather than
I looked up Judith Curry and found the following article:
Climate Science and the Uncertainty Monster
We quickly find the following quote about people detecting the monster
The third type is the merchant of doubt (Oreskes and Collins 2010), who
distorts and magnifies uncertainties as an excuse for inaction for
financial or ideological reasons
Who does that remind us of?
The other amusing thing about the article is a reference to a previous
uk.rec.cycling contributor (Annan, J. D). A person with whom I had a
discussion about how uk groups get distorted by a few like minded
zealots promoting a stupid non scientific agenda. Their argumentative
style rejecting cycle helmets was very similar to your resistance to
On 09/02/2017 09:58, Chris Hogg wrote:
You think the hypothesis of Global Warming is a straw man? You do
Well, climatologists of course, although in their case it's action
rather than inaction.
To laugh at Curry's article merely because you had an argument with
the author of one of her references regarding cycling helmets is ad
hominem, does you no favours, and is in fact a quite extraordinary
line of thinking. You should be ashamed!
In this particular instance I was just the messenger, posting links to
a couple of articles that might be of interest to those here who take
an alternative view of the Global Warming hypothesis. I note you've
not attempted to engage with details of either of the articles. But I
do draw my views on the correctness or otherwise of that hypothesis
from the likes of Prof. Curry and several other very well qualified
and experienced climatologists, as well as a consideration of
alternative theories that account for the observed variations in
global climate temperatures, which tend to be ignored by the
'believers' such as yourself.
I trust you've expressed your opinions in the 'comments' section of
Curry's blog or the WUWT blog, where you may get a rather more
detailed response that you'll get from me.
THe Strawman is that climate models can predict global temperatures with
precision or with certainty. The argument goes:
"the climate change advocates said temperatures would rise at a
particular rate and over the last x years they haven't. Hence the
hypothesis of Global Warming is wrong and we can burn as much coal as we
like. There is no man made global warming"
OK. there was no certainty smoking tobacco was harmful. There was no
reason to believe thalidomide caused birth defects, how could aerosols
hurt the ozone layer?
The precautionary principle is that the vast majority of scientific
opinion believes CO2 emissions are significantly affecting the climate.
There is a significant possibility that this Global Warming could be
catastrophic. It would be prudent whilst this is a significant
possibility to minimise CO2 emissions until we have better models to
predict how much warming will occur.
I was laughing at what a small world it is. Curry's article was quite
reasonable. I work with similar models (not climate related). I know the
uncertainty she is talking about. With the models I'm familiar with the
maxim goes: that they can be good for helping interpolation between know
values but should not be trusted to extrapolate.
It is not Curry's article that is wrong but the way it is
misinterpreted. We tell children that it is dangerous to run across the
road because they will be run over and killed. Given a relatively low
level of traffic on most roads it is actually quite unlikely that this
will happen any time they do it. However I think most of us would agree
it is not sensible to big this uncertainty argument up to children and
encourage them to continue running across roads without looking.
I actually come to this group to look at DIY. I suppose I should ignore
That's odd, the argument is that the models don't predict what has
actually happened so they can't be used to predict what will happen.
Just compare what they predicted ten years ago with what has actually
happened and you will have enough proof that the models then were wrong.
They were wrong twenty years ago.
They were wrong thirty years ago.
Just what evidence is there that they aren't wrong now?
Then there is the problem of some scientists tampering with the data to
make it fit their model, which is what started this thread in case you
Its also what the thread is about.
OK, from what you're saying here and in our previous discussions, we
shouldn't be concerned about short-term deviations from the results
predicted by theory, in what is a stochastic process (whilest being a
bit vague as to what defines short-term).
My take on global warming is as follows. Up until say the 1980's,
nobody gave global warming a thought. I recall that in the 1950's
people were even talking about the world heading towards a new Ice
Age. Then in the 1980's it was seen that global temperatures had
started to rise. Climatologists cast around for an explanation, and
someone dusted off a suggestion by the Swedish scientist Arrhenius in
1896 that carbon dioxide from burning fossil fuels might cause a rise
in global temperatures.
As with all hypotheses, the idea was explored, developed, theoretical
models constructed and alternative hypotheses considered. The
modelling was complicated, because of the range of variables involved
and the considerable uncertainties in quantifying them, especially as
some form of feedback, aka 'forcing', had to be invoked to get the
models to work at all.
But despite those difficulties, a model was evolved that purported to
describe the dependency of global temperature on the CO2 content of
the atmosphere. With a bit of subjective manipulation of the magnitude
of the factors involved (aka curve fitting), a tolerably good match
was achieved between theory and observation. Climatologists got very
excited, and everyone else became familiar with the shape of a hockey
stick even if they didn't know what one looked like before.
Alternative hypotheses were cast aside as being no longer needed; the
answer had been found.
Based on the models, global warming was predicted to reach alarming
levels very soon if the emission of CO2 was not drastically abated.
The world went into panic mode. Environmentalists and supporters of
renewable energy thought all their Christmases had come at once.
Wind-generator and solar panel manufacturers rubbed their hands with
glee, anticipating huge markets when previously they only had niche
markets supplying a few isolated communities.
But according to you, we should never have been concerned about the
rise in global temperatures 1975-2000 in the first place. It is after
all a stochastic process and that sort of thing happens over
relatively short time scales, just as the period of cooling happened
between 1880 and 1910, and again between 1945 and 1975; it's what
stochastic processes do.
But then, starting about 2000, temperatures stopped rising, and with
the exception of 2016 which was a very strong El Niño year, have been
pretty steady ever since. 'No matter', you say, 'such things are to be
expected in a stochastic system; ignore it; see the bigger picture;
stick with the model, it must be correct'. In which case, why is it
that for the last fifteen years or so, climatologists have been
scurrying around trying to explain 'the pause' (which you say we
should ignore anyway), either by re-interpreting the data, adjusting
the data, finding new reasons why the data was incomplete etc. They
wouldn't be doing that if they were so confident that the theories
were sound, and the pause was just what stochastic processes do from
time to time.
Then there are the scandals/rumors/whatever about researchers being
selective with the data, data being tampered with etc. and not least
the recent fuss about NOAA scientists not following established
protocols in verifying their data and apparently not keeping the
source material. How valid those various accusations are I don't know,
but it does the credibility of the AGW hypothesis no favours, and I
struggle to believe it's all just anti-AGW propaganda.
Meanwhile, other theories are seemingly ignored, even though they
appear to predict the changing pattern of global temperatures rather
better that do those of CO2 emissions, stochastic processes
Further, satellite measurements of the temperature of the troposphere
(the lower part of the atmosphere, where all the weather is), show
only a slow overall increase in global warming over the period 1979 to
present, not the sharp rise 1975-2000, and nothing to be concerned
about. Yet they pick up the El Niño excursions quite clearly. So what
gives? Something's not right there.
And then there is the fairly trivial point of the subtle but Orwellian
change in emphasis from it being 'Global Warming' to 'Climate Change'
reminding me of the change from 'All animals are equal' to 'All
animals are equal but some are more equal than others'!
Something is rotten in the State of Denmark! The hypothesis of
anthropogenic global warming is a castle built on sand. Climatologists
have a long way to go before they understand properly the factors
controlling global temperatures. They don't even know why El Niño
happens, so why should they think they understand the bigger picture?
<snipped bit about precautionary actions)
I am slightly puzzled. I've not read the Curry article you linked to
other than to confirm your quote, but she's a leading advocate in
opposing the hypothesis of AGW, so either you've misinterpreted her or
she's not following her own dictum.
As you will have realised by now, it's a group with very catholic
tastes, not just plastering, painting and plumbing. Politics
(especially Brexit), immigration, climate change, renewable energy,
all get a good thrashing here. It makes for a very active and lively
group, when many other groups are fading.
I could reply to each point but it would take a long time.
Perhaps I could clarify. AIUI There is no precise reliable model of how
the global climate acts, even excluding CO2. When I say things are
modelled stochastically, this is an admission of ignorance, we model
things using statistics and stochastic processes because we can't model
them deterministically. We are not sure about stuff. However by
mathematical magic we can still glean some predictive power from such
models, which is why we use them. In physics these statistical models
can become precise, e.g. when we model things like gas particles, but in
fields like climate change this precision doesn't occur
Many of the stochastic processes we use have a mean reverting random
component and a long term deterministic drift. In the short term the
random stochastic noise dominates, drowning out evidence of drift, in
the long term however the drift may dominate. This is why it is very
difficult to make deductions about drift in the short term. I am vague
about short term and long term because these concepts are determined by
the relative magnitudes of the variance of the stochastic component
compared to the magnitude of the drift over time.
As far as I can see Curry does not reject AGW. In fact she accepts it.
She is instead rejecting the way the ideas are presented and governments
reactions to them. In particular she states the current actions to limit
CO2 are not enough to significantly affect AGW and secondly she does not
expect AGW to be catastrophically bad by the end of the century, < +2
instead of > +4 degrees. However as she admits there is a great deal of
I think it is you who misinterpret and misrepresented Curry. I suspect
the reason she has been ostracised from the global warming is because
she makes it easy for people to misrepresent her arguments as
You have got to remember that even in the climate science community only
a few will have the technical expertise to understand how the models
work or what they really mean.
I can see we're going to have to agree to differ on this.
Did you read the PDF article she prepared for a group of lawyers in
response to a request for a view on the models used to predict global
warming, the link to which I put at the top of this thread? I
reproduce the Exec. Summary here:
"There is considerable debate over the fidelity and utility of GCM
climate models. This debate occurs within the community of climate
scientists, as scientists disagree about the amount of weight to give
to climate models relative to observational analyses. Climate model
outputs are also used by economists, regulatory agencies and policy
makers. Hence, GCMs have received considerable scrutiny from a broader
community of scientists, engineers, software experts, and philosphers
of science. This report attempts to describe the debate surrounding
climate models to an educated but nontechnical audience.
Key summary points:
. GCMs have not been subject to the rigorous verification and
validation procedures that is the norm for engineering and regulatory
. There are valid concerns about a fundamental lack of predictability
in the complex nonlinear climate system.
. There are numerous arguments supporting the conclusion that climate
models are not fit for the purpose of identifying with high confidence
the proportional amount of natural versus human causes to the 20th
. There is growing evidence that climate models predict too much
warming from increased atmospheric carbon dioxide.
. The climate model simulation results for the 21st century reported
by the IPCC do not include key elements of climate variability, and
hence are not useful as projections for how the 21st century climate
will actually evolve.
Climate models are useful tools for conducting scientific research to
understand the climate system. However, the above points support the
conclusion that current GCM climate models are not fit for the purpose
of attributing the causes of 20th century warming or for predicting
global or regional climate change on timescales of decades to
centuries, with any high level of confidence. By extension, GCMs are
not fit for the purpose of justifying political policies to
fundamentally alter world social, economic and energy systems. It is
this application of climate model results that fuels the
vociferousness of the debate surrounding climate models."
That seems pretty damning of climate models to me, put diplomatically
Summary - a naughty scientist reveals, to the common folk, that other
scientists cannot see the future, clearly.
Who'd thunk it? Weather forecasts not always accurate!
However scientists are sure* (*trademark = 95% confident) that we are
having a warming period over and above what we would have naturally.
This includes Ms Curry.
OK I can see you are rightly shocked and appalled that your future is
not clearly mapped out for you, so what do you do?
A) Decide all scientists are charlatans and can be ignored. If there
advice isn't perfect I'm not touching it. I understand the world is
getting hotter but no one can prove I'm to blame so we'll just have to
wait to see how hot it gets.
B) Think oh dear! The world is getting hotter. I wonder how hot it will
get. Just in case there is a catastrophe I will try to stop what
scientists tell me I'm doing that causes the warming. I don't know what
will happen for sure but I will accept an, imperfect, best guess from
I've also had a look at some of the other stuff Curry has said, in
particular arguments she was using to reject the precautionary
principle. Some of it looked a bit odd. Firstly she was assuming a
roughly normal PDF for the risk of catastrophe, prompting me to go why,
WTF? Secondly she was quoting an example that the precautionary
principle dictates that we should be defending against asteroid strike
rather than global warming. She said the risk of asteroid strike is more
uncertain. AIUI the risk of asteroid strike is relative well known to be
very small. So again I was left wondering about her ability. But of
course I'm not an expert in the field and I'm just anonymously shooting
the breeze in a diy group.
The point is that with people who want to oppose a scientific orthodoxy
they will normally be able to find one or two scientists ready to break
ranks and support them. This may be because the scientist is genuinely
stupid, a PHD often doesn't seem to require a sharp mind, or because the
scientist may see some advantage in doing so (fame, cash).
When global warming first became news and of public concern, I, like
most, was quite convinced of the problem, and was scornful of those
who doubted it. But over the intervening twenty or so years, the more
I read, the more sceptical I became.
It is sad that those few climatologists who have spoken out against
the hypothesis of AGW have been so widely vilified, even though those
climatologists are very experienced and at one time highly respected
in their fields.
It is also sad that you seem to be going along with that vilification,
a great deal of which is blatant 'ad hominem' attack with no
consideration of the scientific arguments or respect for the
experience of the scientists in question.
They were revealing, because they showed that the scientists had some
doubts. This is no criticism, and no bad thing at all. Feynman used to
point out that you could recognise really good scientists by the trouble
they took to test and try to invalidate their current pet theory.
Something we don't seem to see enough of these days, IMHO.
One of them said something like "We need to get rid of the medieval warm
period" which was taken by some to imply a serious proposal to
deliberately cook the figures.
I take the more charitable view that this was a shorthand within the
group to say that the simplest models were not going to be viable. There
is nothing wrong at looking at data which don't seem to support a theory
firstly to see whether they are in fact correct and, if they are, then
whether there is a subsidiary explanation for them which does not
invalidate a more general model.
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