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Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by curryja


Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by David Wojick

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Both of your claims are clearly false. I deliberately misinform no one and I do lots of research. What are we to make of your glaring errors?

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by frankclimate

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As Judy states in response to your words: ” How accurate are climate models?” Please re-read the mainpost with this in mind!

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by David Wojick

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Frank, I have no idea what your oxymoron claim is about. If the only warming in the satellite record is due to the giant El Nino, then there is no GHG induced warming. Seems perfectly clear to me.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by frankclimate

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vtg: “I realise this post will likely not stay up long, these truths are not welcome.” I think it will. Because the truths in the mainpost ( summerized in the last sentence of the conclusions) are IMO thruths that should be considered.

Comment on Sea levels, atmospheric pressure and land temperature during glacial maxima by Robert I. Ellison

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“The covariation of carbon dioxide (CO2) concentration and temperature in Antarctic ice-core records suggests a close link between CO2 and climate during the Pleistocene ice ages. The role and relative importance of CO2 in producing these climate changes remains unclear, however, in part because the ice-core deuterium record reflects local rather than global temperature. Here we construct a record of global surface temperature from 80 proxy records and show that temperature is correlated with and generally lags CO2 during the last (that is, the most recent) deglaciation. Differences between the respective temperature changes of the Northern Hemisphere and Southern Hemisphere parallel variations in the strength of the Atlantic meridional overturning circulation recorded in marine sediments. These observations, together with transient global climate model simulations, support the conclusion that an antiphased hemispheric temperature response to ocean circulation changes superimposed on globally in-phase warming driven by increasing CO2 concentrations is an explanation for much of the temperature change at the end of the most recent ice age.”

http://www.atm.damtp.cam.ac.uk/mcintyre/shakun-co2-temp-lag-nat12.pdf

Both biokinetics and geophysics suggest that substantial lag between CO2 and temperature is improbable. It seems rather to be more an artifact of antiphase polar warming.

e.g. – https://s3.amazonaws.com/academia.edu.documents/33489657/QSR-Ohetal.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1546808572&Signature=eYDVex8KSabW5suta6cFLAPODgU%3D&response-content-disposition=inline%3B%20filename%3DPolar_synchronization_and_the_synchroniz.pdfhttp://www.ajsonline.org/content/312/4/417.abstract

More generally I find the geophysics of this post problematic, the assumptions and calculations simplistic and the presentation crude.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Javier

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Tony, the cooling part is c. 100-250 years, the warming part is more variable, 50-300 years. I am still studying the data between 2.5 and 0.5 kyr BP, but outside this period, the list so far includes:
Date
11.4
10.3
9.3
8.6
8.4
8.2
7.7
7.2
6.8
6.3
5.5
5.2
4.6
4.2
3.1
2.9
2.7
0.4

There should be probably one or two more from the 2.5-0.5 period.

There’s bibliography on most of them, but not on all. People tend to study just the 8.2 and the LIA (0.4).

There are 3-4 types of events. By far the most common one is characterized by cooling, wetter Middle East, weaker Asian Monsoon, decrease in methane, increase in North Atlantic iceberg activity. This is the low solar activity pattern.

The 8.2 is a type of its own, characterized by cooling, wetter Middle East, weaker Asian Monsoon, and super decrease in methane, but no increase in iceberg activity. Caused most probably by the meltwater pulse from Lake Agassiz.

Another type is characterized by moderate cooling, extra-drying of the Middle East, little to no effect on the Asian Monsoon, and no increase in North Atlantic iceberg activity. I have no idea what causes these ones.

The 4.2 kyr event is very similar to this type, but could be a type of its own, as it has a unique signature in several proxies from the Indian Ocean Area (East Africa, Arabia, West india). I think this one could have been an impact.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Javier

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IMO this is wrong:

I’ll stick to my guns. HadCRUT4 doesn’t show it and I am not interested in yet another discussion about the goodness of datasets. HadCRUT4 is good enough for IPCC and good enough for me.

Everybody with the opinion that the solar forcing has more impact than the forcing data say has to acknowledge that the SC24 ( since 2008) was the weakest cycle since SC6 ( this was around 1815) and the GMST didn’t decline since SC23. This is without any doubt IMO. So you are left with the question: what is the source of this warming? The only possible response: The anthropogenic forcing has much more impact on the GMST than used the original forcing data. Which means: more sesitivity!! This is the wicked problem of all “it’s the sun stupid” fellows.

This just show what are your assumptions about how the Sun affects climate. If you tell me your assumptions I’ll tell you your conclusions, that doesn’t mean they are the right ones.

If you were to read a little more paleoclimatology you would know that the effect of low solar activity on climate has a significant lag. I recommend Takuro Kobashi. That’s the main reason a single solar minimum has very little effect on climate. You start to see the effect after a low cycle (now), and more intensely after two low cycles (20-year lag) when the lost energy starts to have an important impact even during summers.

Meanwhile in the short time of low solar activity we are having since c. 2005, of only 13 years, its effect has already quenched the entire effect of the increase in CO2 for that period (c. 28 ppm), plus the heat released by one of the strongest Niños in recorded history, since unlike what happened after the 1998 El Niño, no step warming has taken place afterwards driven by a strong La Niña.

As there is little heat left to be released from the Pacific, now comes the cooling. No global warming is possible for as long as solar activity remains below average.


Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Robert I. Ellison

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“Climate is ultimately complex. Complexity begs for reductionism. With reductionism, a puzzle is studied by way of its pieces. While this approach illuminates the climate system’s components, climate’s full picture remains elusive. Understanding the pieces does not ensure understanding the collection of pieces.” Marcia Wyatt

Small changes in the complex dynamical Earth system drive large abrupt changes in response. It is the nature of deterministic chaos. It is suggested that Hale cycle of solar magnetic reversal drives 20 to 30 year periodicity in the resonant Earth system. Very little is known of the ‘control variables’ that bias the system to one state or other or the multiple interactions of powerful subsystems that shift the system to a new state. But this is the dominant Earth system paradigm.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Robert I. Ellison

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The multidecadal link between the Pacific state and surface temperature is via shortwave modulation of ocean heat content through cloud feedback.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by climatereason

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Robert I. Ellison

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Answers to any of those questions require knowledge of methods and their limitations – geophysics rather than metaphysics.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by curryja

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This post stays, your others have been deleted. Attacking a commenter is not allowed, attack the arguments instead.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by dpy6629

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I suspect what is going on here vtg, is the moderating of ad hominem comments and trying to keep off her blog the familiar political hatchet job tactic of quote mining someone’s vast public record for anything offensive to be used to discredit them forever.

Very few take seriously this idea that CO2 increase is not due to fossil fuel use. There will always be some who believe it but its completely unimportant to have perfect unanimity. Trying to drive an idea out of the public square is not going to work and is a waste of precious life energy.

Frank’s post here is very interesting and shows something very interesting I think, namely, how important effective forcings are for estimating TCR. It also shed some light for me on how climate models can disagree so much with historically constrained energy balance methods.

Elsewhere Frank (perhaps another one) pointed out that effective forcings in climate models vary over a surprisingly broad range. Further a high aerosol negative forcing can compensate for a high TCR and allow a model to replicate the historical global mean temperature by essentially cancellation of errors. Similar observations apply for ocean heat uptake which is too high in models according to this Frank.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by jdmcl

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Referencing a paper doesn’t automatically mean it’s reliable.
National meteorological services now do their own adjustment – which makes sense because they know more about the conditions – so if they have incorrectly adjusted the data before supplying it to other people then any processing of that data that those people do will also be incorrect.


Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by john321s

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Mind you I doubt regression analysis works with step functions, unless you do before and after separately.

Regression analysis not only fails to work with step functions. it fails to work with anything other than a static, memoryless linear relationship between excitation and response. In fact, it tacitly forces that assumed relationship upon the data. The climate system is nowhere near that simple, and attempts to explain its workings via linear regression are predestined to be misleading, at best. One waits in vain for “climate science” to grow up and embrace the well-developed methods of signal and system analysis (q.v.).

BTW, while step functions can be useful analytic constructs, no physical system with any inertia manifests a response exactly of that form.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Ragnaar

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How accurate are climate models, paleo data, ocean heat content data, and TOA incoming/outgoing? With ECS still not well constrained what good is it? Know >>> Act. Know has to be at a high enough level to Act. Or it’s reckless. Some of the best knowledge we have is what we can do in the United States in regards to mitigation is going to have a small impact and with current technology is going to cost a lot. Then we could argue we have duty to the world. That’s not physics. The higher valued knowledge of economics as compared to the climate science, tells us to adapt and this is still not physics. So physics is telling us we aren’t really sure. But economics tells us it sure costs a lot.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by matthewrmarler

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David Wojick: <i> I think it is important to point out that most of the climate change scientific debate is about epistemic questions, not physical questions. How accurate are climate models? How accurate are paleoclimate proxy reconstructions? How accurate are global statistical claims?</i> This point is made over and over again.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by Robert I. Ellison

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Models have irreducible imprecision for reasons many cannot seem to comprehend.

https://www.pnas.org/content/104/21/8709
https://royalsocietypublishing.org/doi/full/10.1098/rsta.2011.0161

All paleoclimatology has methodological limitations.

https://www.nap.edu/read/10136/chapter/3#13

Modern data is as precise and comprehensive as it can be – albeit with short records. And not widely appreciated for what it is.

https://journals.ametsoc.org/doi/10.1175/JCLI-D-17-0208.1

http://www.argo.ucsd.edu/global_change_analysis.html

But the Earth system is a wild and angry beast in all of it.

Comment on Reconstructing a dataset of observed global temperatures 1950-2016 from human and natural influences by climatereason

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Javier

Just to ensure I understand your nomenclature can you confirm that 0.4 means around 1600AD?

The temperature definitely declined around 1560 and was generally, but not always cool until around 1700. What would be the mechanisms by which warm periods would interrupt the cool ACE?

There were certainly extended cool periods around 1200 and around 550 to 650AD. How would it be determined if they were affected by a cool ACE?

Tonyb

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