The conversation should first be about GCMs and whether they can simulate the current climate, and the answer is yes, enough is known about the fluid equations, the heating from the sun, water effects, and radiative transfer to give a good rendering of the climate, including pole-equator temperature and seasonal changes around the world. Try running a GCM without CO2 or with the wrong amount, and they will fail, for the reason that the CO2 we have helps to determine the climate we have, along with our distance from the sun and the net albedo of earth’s various surfaces. To the extent that GCMs have succeeded in simulating climate and are used as tools for understanding it, they can also be used for climate change studies, especially with what by climate standards are small perturbations that may change temperatures by only a fraction of the global and seasonal range. So, to disqualify a climate model, first you have to disqualify the GCM on which it is based. If it passes as a GCM, it passes as a climate model for small (~1% forcing) perturbations like doubling CO2.
Comment on How far should we trust models? by Jim D
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Comment on How far should we trust models? by steven
Models can’t predict the AMO or the PDO. That means we don’t understand heat transfer well enough to program it in the models. The same forcing can cause a snowball earth or an ice free earth depending on how heat is transfered. We are a long way from understanding the climate and climate models have no use other than perhaps helping to identify what we don’t know.
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Comment on The blogosphere and thought leaders by Max_OK
Apparently the Pope thinks people like GaryM and jim2 have a “crude and naive trust” in free-market and trickle-down theories.
I’m with the Pope on this, but I would put it more succinctly.
I think those guys are silly saps.
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Comment on Data corruption by running mean ‘smoothers’ by RichardLH
Greg: So what you do instead is to effectively imply a linear trend instead by discounting any longer cyclic alternative and suggesting a derivative or some such is used which is basically the same thing.
You suggested that my removal of the ~60 term by simple low pass filtering and observing that the final term was NOT a straight line was not useful or relevant.
I then point out that this ‘low point at the start of the record’ is supported by longer term data from other sources.
You sidestep that point.
AFAIK an FA can only reliably be used to observe cycles with periods less than approximately half the length of the data series on which they are run. Yet people (including yourself) will regularly display outputs and derive conclusions with periods much longer than that in them. No problems with that?
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Comment on How far should we trust models? by Jim D
steven, the AMO and PDO are consequences of chaotic ocean motions, and just because it can’t track a particular chaotic fluctuation, doesn’t disqualify a model from defining a mean state. Chaotic motions are initial value problems, not boundary value problems as climate is. It is the same fallacy as “you can’t tell if it will rain next week, so you can predict climate change”, but I think people are unable to see that AMO and PDO are the ocean’s version of weather fluctuations that happen on its longer time scales. Ocean “weather” is slow motion compared to the atmosphere with certain patterns taking years to play out.
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Comment on How far should we trust models? by Mi Cro
you could think of climate science the same way.. except that they are not feeding back errors. Its more a problem of HOW they are responding to their imperfect predictions RATHER THAN the fact that a model made an imperfect prediction. Thats because they oversold models as truth engines. they are not.
Steven, I fully agree with this. To take it one step further, I don’t think they provide a valid projection for a world of increasing Co2, but are sold as if they do, this is my issue with climate science, they took a hypothesis and tried to turn it into policy, and the scientists who should know better didn’t protest. And not just any policy, one that would turn the entire worlds economy on it’s head.
I find this the height of arrogance and stupidity. If they didn’t do this, I’d consider the matter much as I do dark matter, something to spend a little money on and go figure out. If they didn’t do this, I wouldn’t care if people made up data for places that are never actually measured :)
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Comment on How far should we trust models? by steven
Jim, so how many years before the chaos averages out? How many longer variations of chaos are there? How do you know it is chaotic if you don’t know what causes it? It isn’t a fallacy to state that if you don’t understand why something happens that you don’t understand why something happens. It doesn’t matter if you will know anytime soon or not. Let me know when you can explain the Gulf Stream reconstruction that shows it slowing from the MWP to the LIA and then increasing again to the present warming period.
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Comment on The blogosphere and thought leaders by Kilroy
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Comment on UK Parliament: IPCC 5th Assessment Review by Antonio (AKA "Un físico")
Hi plaza, have you read all the pdfs submited to that UK thing? It would be very interesting if you sumarize all them in your blog (in a table-like presentation). I have not visited your blog for a while, but if you get that table, I could check if some of my ideas in:
https://docs.google.com/file/d/0B4r_7eooq1u2VHpYemRBV3FQRjA/
have been shared by any of the submitters. [my ideas are: (1) climate sensitivity value estimation is science fiction, (2) abusing of montecarlo methods in order to attribute climate change to mankind is incorrect and (3) climatic models are not reliable as they are based in THAT climate sensitivity and as they require at least 900 years of data compilation to work properly].
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Comment on UK Parliament: IPCC 5th Assessment Review by WebHubTelescope (@WHUT)
Edim,
By applying Nic Lewis’ recommended approach of energy-budgeting, we can clearly see that the effects of ENSO act as a compensating factor in obscuring the underlying temperature rise.
Using an approach such as CSALT, we can apply the ENSO SOI pressure term as a compensating energy budget factor and thus reveal the actual TCR of 2C.
http://imageshack.com/a/img801/3483/bhb.gif
Voila, we use Nic Lewis’ recommended approach and we get closer to the truth. See how it works?
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Comment on UK Parliament: IPCC 5th Assessment Review by Nic Lewis’ submission to the AR5 inquiry « De staat van het klimaat
[…] are now online. Many interesting things to read. Lots of critical submissions. Judith Curry calls Nic Lewis’ contribution a “tour de force” which it really is. Some readers here might know that Nic and I have been working for the past few […]
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Comment on UK Parliament: IPCC 5th Assessment Review by David Springer
The null hypothesis is that there is no relationship between two measured phenomenon. If the hypothesis put forward is that CO2 causes surface warming the null hypothesis is that CO2 does not cause surface warming. If the hypothesis is that a new drug cures disease the null hypothesis is that the drug does not cure disease.
Don’t make this more complicated than it needs to be. Saying the null hypothesis can be anything is what a weasel would want. When it comes to climate weasels just say no.
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Comment on UK Parliament: IPCC 5th Assessment Review by captdallas 0.8 or less
“So the null to that is available.”
95% confidence that 50% of the warming since 1951 is due to some form of human activity is not likely to be falsified using “Global” surface temperature since about 30% of the warming is over land and GISS interprets high latitude and higher altitude warming as “surface” warming.
The way GISS interprets the “surface” there can be a 0.4C swing in temperatures with no change in actual “surface” energy. We have to wait and see how much the NH high latitude temperature drop after the internal “AMO” shift and then they can switch metrics or claim the shift is due to human influences.
So they have a very defensible position even though it really doesn’t mean much.
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Comment on UK Parliament: IPCC 5th Assessment Review by Pekka Pirilä
If we don’t want to draw conclusions from one specific model like CSALT, we may try to look at the data in a way where the highs and lows appear to compensate. Looking at the figures of the Otto et al paper (with Nic as one of the many coauthors) the two last decades form a plausible combination for that. Based on that the best estimate for TCR is about 1.8C, the value proposed in AR5 as well.
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Comment on UK Parliament: IPCC 5th Assessment Review by David Springer
+1
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Comment on UK Parliament: IPCC 5th Assessment Review by David Springer
I’m kind of wondering why such a hot year as 2013 was such a dud for hurricanes. This is the first year since 1964 that no hurricane exceeded category 1. The climate boffin bandwagon position is that global warming results in more severe weather not less. What’s up with that?
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Comment on UK Parliament: IPCC 5th Assessment Review by Jim Cripwell
David, you write “I’m kind of wondering why such a hot year as 2013 was such a dud for hurricanes.”
Maybe the simple explanation is that we just don’t understand climate. Mother Nature is just doing what she has been for billions of years, and we have, as yet, not worked out what the fundamentals are.
No doubt the universe is unfolding as it should.
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Comment on UK Parliament: IPCC 5th Assessment Review by Jim Cripwell
Am I correct in believing that the UK parliamentary web site giving access to all these papers, is unique, where the arguments for and against CAGW are all contained in a single reference?
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Comment on UK Parliament: IPCC 5th Assessment Review by WebHubTelescope (@WHUT)
CSALT gives a TCR=1.84C using HADCRUT4 and TCR=2.14C using GISS.
As a tiebreaker CSALT gives a TCR of 2.08C using the NRDC land-sea data.
That is why I do not understand the low-ball estimates of TCR of 1.3C that Nic Lewis keeps proposing. Can he not interpret the empirical data? It is clear that HADCRUT is giving at least 1.8C for a TCR, and with the Cowtan&Way corrections, it is 1.94C according to CSALT.
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Comment on UK Parliament: IPCC 5th Assessment Review by Peter Lang
Interesting submission by Nic Lewis.
The take home message (paraphrased):
The worst-case, business-as-usual scenario, with realistic climate sensitivity based on observational results (as distinct from models) and no net natural variations either up or down:
– the end of the 21st century will be approximately 2°C warmer than today.
The meta-analysis in Tol (2009), of fourteen estimates from economists, suggests that a temperature of 2°C warmer than today is likely to have a negligible impact on welfare.
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