The Test and Failure of the AGW Paradigm

[istodolez]

I know that the overall temperature is not affected by the urban heat island effect. I am saying it is impossible to properly correct the meteorological station readings to use and get a global temperature.

And if a "global temperature" were the goal I'm sure you'd have a point. But in the real world of climate science the key factor is the temperature anomaly or the difference in temperature compared to a baseline.

It is actually much easier in many cases to measure DIFFERENCES than it is to measure a single value! That's the glory of elementary school mathematics.

 

[istodolez]

I see lots of controversial opinions mentioned, and no solid corrections.

Again, the Peterson paper merely looks at the effect of Urban Heat Islands on the overall data set. They find no significant impact of the UHI's on the overall dataset.

 

[longview]

Again, the Peterson paper merely looks at the effect of Urban Heat Islands on the overall data set. They find no significant impact of the UHI's on the overall dataset.

No! Peterson just looked at the US data set as stated in the title.

Assessment of Urban Versus Rural In Situ Surface Temperatures in the Contiguous United States:

 

[istodolez]

No! Peterson just looked at the US data set as stated in the title.

Huh? As I've said NUMEROUS TIMES Peterson looked at the USHCN. I thought you knew what the USHCN is.

(Hint: The first two letters should tell you).

When discussing anthropogenic global warming it is really good to know the terms.

 

[longview]

Huh? As I've said NUMEROUS TIMES Peterson looked at the USHCN. I thought you knew what the USHCN is.

(Hint: The first two letters should tell you).

When discussing anthropogenic global warming it is really good to know the terms.

Post # 152, you said,
"They find no significant impact of the UHI's on the overall dataset."
I am pointing out that the Peterson dataset is not the globe, but only the US.
When discussing anthropogenic global warming it is really good to understand what is global vs what is not!

 

[istodolez]

Post # 152, you said,
"They find no significant impact of the UHI's on the overall dataset."

AND, if you had either read my previous posts or even bothered to crack the Peterson paper you'd see that by "overall dataset" I was talking about the USHCN.

Wow.

I am pointing out that the Peterson dataset is not the globe, but only the US.

And at NO POINT have I EVER said it was a reference to the global.

It is merely to note that UHIE appears to have no discernible impact on the USHCN. (Now it is reasonable to assume that ceteris paribus that if UHIE don't negatively impact the USCHN then it may not impact global, but at no point have I EVER in this discussion made claims about the global.)

When discussing anthropogenic global warming it is really good to understand what is global vs what is not!

At least I've been reading stuff. You just respond without actually reading what is written! Yikes!

You really should learn more about the details of the topic from the actual LITERATURE. But that WILL require you read.

 

[longview]

AND, if you had either read my previous posts or even bothered to crack the Peterson paper you'd see that by "overall dataset" I was talking about the USHCN.

Wow.




And at NO POINT have I EVER said it was a reference to the global.

It is merely to note that UHIE appears to have no discernible impact on the USHCN. (Now it is reasonable to assume that ceteris paribus that if UHIE don't negatively impact the USCHN then it may not impact global, but at no point have I EVER in this discussion made claims about the global.)



At least I've been reading stuff. You just respond without actually reading what is written! Yikes!

You really should learn more about the details of the topic from the actual LITERATURE. But that WILL require you read.

I have a reason to be specific, the US temperature record shows very little change in Maximum temperatures.
Climate at a Glance | National Centers for Environmental Information (NCEI)
So discussing UHI effects on the US record, would not tell us much, about maximum temperatures.
The minimum temperatures have increased quite a bit, which brought up the average temperature.
Climate at a Glance | National Centers for Environmental Information (NCEI)
What I am saying is that looking for a secondary signal, when there is minimal primary signal, means little.
You keep pointing to a single paper looking at the UHI effect in the adjusted US data set, but there are many other papers
showing it has an impact on the global temperatures, and how to adjust for it.

 

[istodolez]

So discussing UHI effects on the US record, would not tell us much, about maximum temperatures.

One other poster (not sure if it was you or another) noted that urban heat islands and station siting would make it difficult to get a good measure of temperature anomalies. I merely pointed that the the evidence shows otherwise.

You keep pointing to a single paper looking at the UHI effect in the adjusted US data set, but there are many other papers
showing it has an impact on the global temperatures, and how to adjust for it.

I have not yet seen any papers that indicate it affects the temperature anomaly.

I have seen you or others post papers that show that the Urban Heat Island effect is REAL, which I have never disagreed with. UHI's are real! I will say it a billion trillion times. That does NOT mean they will impart a systemic bias that significantly changes the overall anomaly calculated from the temperatures.

 

[longview]

One other poster (not sure if it was you or another) noted that urban heat islands and station siting would make it difficult to get a good measure of temperature anomalies. I merely pointed that the the evidence shows otherwise.



I have not yet seen any papers that indicate it affects the temperature anomaly.

I have seen you or others post papers that show that the Urban Heat Island effect is REAL, which I have never disagreed with. UHI's are real! I will say it a billion trillion times. That does NOT mean they will impart a systemic bias that significantly changes the overall anomaly calculated from the temperatures.

We have digressed from the real conversation, the difference between AGW and catastrophic AGW!
The empirical data shows that AGW, while real, exists in a tightly limited range very near the simple greenhouse gas forcing level.
The net of all the feedbacks is, perhaps slightly positive, but within the error margins.
Even some of the lead authors of the last IPCC report, have shown that the 2XCO2 ECS based on observations,
is between 1.9 and 2C.
https://ethz.ch/content/dam/ethz/sp...documents/group/climphys/knutti/otto13nat.pdf

The most likely value of equilibrium climate sensitivity based on the energy budget of the most recent decade is 2.0 °C,
with a 5–95% confidence interval of 1.2–3.9 °C (dark red, Fig. 1a), compared with the 1970–2009 estimate of 1.9 °C

Actually evaluating how the climate has responded to past warming perturbations, shows that 2XCO2 ECS is roughly 1.2 to 1.6C.
If the 2XCO2 ECS is as Otto found for the 1970 to 2009 period, 1.9C, then the first doubling of CO2 280 ppm to 560 ppm,
would equalize out that 1.9C of warming over a 180 year period. Some of that 1.9C could take another century to equalize.
A second doubling, if even possible, from 560 ppm to 1120 ppm, would take, several hundred years.
Add on top of all of this, the majority of the average warming, is happening in winter and evening low temperatures,
and the result is minimal concern for AGW!

 

[Surface Detail]

We have digressed from the real conversation, the difference between AGW and catastrophic AGW!
The empirical data shows that AGW, while real, exists in a tightly limited range very near the simple greenhouse gas forcing level.
The net of all the feedbacks is, perhaps slightly positive, but within the error margins.
Even some of the lead authors of the last IPCC report, have shown that the 2XCO2 ECS based on observations,
is between 1.9 and 2C.
https://ethz.ch/content/dam/ethz/sp...documents/group/climphys/knutti/otto13nat.pdf

Actually evaluating how the climate has responded to past warming perturbations, shows that 2XCO2 ECS is roughly 1.2 to 1.6C.
If the 2XCO2 ECS is as Otto found for the 1970 to 2009 period, 1.9C, then the first doubling of CO2 280 ppm to 560 ppm,
would equalize out that 1.9C of warming over a 180 year period. Some of that 1.9C could take another century to equalize.
A second doubling, if even possible, from 560 ppm to 1120 ppm, would take, several hundred years.
Add on top of all of this, the majority of the average warming, is happening in winter and evening low temperatures,
and the result is minimal concern for AGW!

The first line of that 2013 paper is: "The rate of global mean warming has been lower over the past decade than previously.", and this forms the basis of authors' subsequent argument. However, the fact that the rate of global warming since 2013 has been much greater than that seen during the decade prior to 2013 renders the argument void. What we learn from this is that 10 years is simply too short a period on which to base such claims.

 

[longview]

The first line of that 2013 paper is: "The rate of global mean warming has been lower over the past decade than previously.", and this forms the basis of authors' subsequent argument. However, the fact that the rate of global warming since 2013 has been much greater than that seen during the decade prior to 2013 renders the argument void. What we learn from this is that 10 years is simply too short a period on which to base such claims.

You forgot the "compared with the 1970–2009 estimate of 1.9 °C "
The overall trend from 1978 to 2019 is .175C per decade, quite a bit lower than the predicted .21C per decade.
https://www.metoffice.gov.uk/hadobs...ries/HadCRUT.4.6.0.0.annual_ns_avg_smooth.txt

 

[istodolez]

We have digressed from the real conversation, the difference between AGW and catastrophic AGW!
The empirical data shows that AGW, while real, exists in a tightly limited range very near the simple greenhouse gas forcing level.
The net of all the feedbacks is, perhaps slightly positive, but within the error margins.
Even some of the lead authors of the last IPCC report, have shown that the 2XCO2 ECS based on observations,
is between 1.9 and 2C.
https://ethz.ch/content/dam/ethz/sp...documents/group/climphys/knutti/otto13nat.pdf

Actually evaluating how the climate has responded to past warming perturbations, shows that 2XCO2 ECS is roughly 1.2 to 1.6C.
If the 2XCO2 ECS is as Otto found for the 1970 to 2009 period, 1.9C, then the first doubling of CO2 280 ppm to 560 ppm,
would equalize out that 1.9C of warming over a 180 year period. Some of that 1.9C could take another century to equalize.
A second doubling, if even possible, from 560 ppm to 1120 ppm, would take, several hundred years.
Add on top of all of this, the majority of the average warming, is happening in winter and evening low temperatures,
and the result is minimal concern for AGW!

Here's Schmidt et al's response to the Otto (2013) article:

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150000726.pdf

Here's where they address Otto et al (2013) directly (emphasis added):

"We conclude that use of the latest information on external influences on the climate system and adjusting for internal variability associated with ENSO can almost completely reconcile the trends in global mean surface temperature in CMIP5 models and observations. Nevertheless, attributing climate trends over relatively short periods, such as 10 to 15 years, will always be problematic, and it is inherently unsatisfying to find model–data agreement only with the benefit of hindsight. We see no indication, however, that transient climate response is systematically overestimated in the CMIP5 climate models as has been speculated8, or that decadal variability across the ensemble of models is systematically underestimated, although at least some individual models probably fall short in this respect."

 

[longview]

Here's Schmidt et al's response to the Otto (2013) article:

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150000726.pdf

Here's where they address Otto et al (2013) directly (emphasis added):

"We conclude that use of the latest information on external influences on the climate system and adjusting for internal variability associated with ENSO can almost completely reconcile the trends in global mean surface temperature in CMIP5 models and observations. Nevertheless, attributing climate trends over relatively short periods, such as 10 to 15 years, will always be problematic, and it is inherently unsatisfying to find model–data agreement only with the benefit of hindsight. We see no indication, however, that transient climate response is systematically overestimated in the CMIP5 climate models as has been speculated8, or that decadal variability across the ensemble of models is systematically underestimated, although at least some individual models probably fall short in this respect."

Except that Otto et al (2013) was trying to increase the ECS with the shorter period. The longer period (1970 to 2009) had an ECS of 1.9C.
https://ethz.ch/content/dam/ethz/sp...documents/group/climphys/knutti/otto13nat.pdf

The most likely value of equilibrium climate sensitivity based on the energy budget of the most recent decade is 2.0 °C,
with a 5–95% confidence interval of 1.2–3.9 °C (dark red, Fig. 1a), compared with the 1970–2009 estimate of 1.9 °C (0.9–5.0 °C; grey, Fig. 1a).
Including the period from 2000 to 2009 into the 40-year 1970–2009 period delivers a finite upper boundary,
in contrast with earlier estimates calculated using the same method.

BTY a 40 year period would remove any ENSO signal.

 

[Surface Detail]

Except that Otto et al (2013) was trying to increase the ECS with the shorter period. The longer period (1970 to 2009) had an ECS of 1.9C.
https://ethz.ch/content/dam/ethz/sp...documents/group/climphys/knutti/otto13nat.pdf

BTY a 40 year period would remove any ENSO signal.

That makes no sense at all. Choosing the period to give a particular result wouldn't be science.

 

[longview]

That makes no sense at all. Choosing the period to give a particular result wouldn't be science.

AGW is not really science, to get published, you have to get passed the reviewers.
They still found that the 2XCO2 ESC based on the time period 1970 to 2009 was 1.9C!
Were AGW real science, the alarmist would not have any issues with a red team blue team test.

 

[Surface Detail]

AGW is not really science, to get published, you have to get passed the reviewers.
They still found that the 2XCO2 ESC based on the time period 1970 to 2009 was 1.9C!
Were AGW real science, the alarmist would not have any issues with a red team blue team test.

AGW is science; it's your interpretation of it that isn't science!

For example, it is simply ludicrous for you to suggest that the authors were "trying to increase the ECS with the shorter period". Do you really think the authors chose the period in an effort to get a specific result? And when they didn't get that result, they went ahead and published anyway? That just makes no sense at all. You seem to have a really weird concept of what constitutes science!

 

[longview]

AGW is science; it's your interpretation of it that isn't science!

For example, it is simply ludicrous for you to suggest that the authors were "trying to increase the ECS with the shorter period". Do you really think the authors chose the period in an effort to get a specific result? And when they didn't get that result, they went ahead and published anyway? That just makes no sense at all. You seem to have a really weird concept of what constitutes science!

Then why is the idea of the consensus, and the settled science so important.
Science is never settled, and consensus is not important in the scientific method.
Science is about seeing the evidence, forming a theory, and seeing if that theory remains valid when tested.
We have evidence that the CO2 level increased, and that the average temperatures have increased.
The idea that added CO2 can force some warming, looks valid, and in some ways can be verified.
The idea that there are net positive feedbacks high enough to have a 2XCO2 ECS of 3C or above, have not been validated in any empirical way.
The only results showing the high feedbacks, are from models, which produce results, based on assumptions of sensitivity.
At this stage AGW, is far more political than scientific!

 

[Threegoofs]

AGW is science; it's your interpretation of it that isn't science!

For example, it is simply ludicrous for you to suggest that the authors were "trying to increase the ECS with the shorter period". Do you really think the authors chose the period in an effort to get a specific result? And when they didn't get that result, they went ahead and published anyway? That just makes no sense at all. You seem to have a really weird concept of what constitutes science!

Well, that’s how Longview approaches science, so he thinks everyone does it that way.

 

[Surface Detail]

Then why is the idea of the consensus, and the settled science so important.
Science is never settled, and consensus is not important in the scientific method.
Science is about seeing the evidence, forming a theory, and seeing if that theory remains valid when tested.
We have evidence that the CO2 level increased, and that the average temperatures have increased.
The idea that added CO2 can force some warming, looks valid, and in some ways can be verified.
The idea that there are net positive feedbacks high enough to have a 2XCO2 ECS of 3C or above, have not been validated in any empirical way.
The only results showing the high feedbacks, are from models, which produce results, based on assumptions of sensitivity.
At this stage AGW, is far more political than scientific!

Well done for completely failing to address the post to which you responded :roll: Have you considered going into politics?

 

[longview]

Well done for completely failing to address the post to which you responded :roll: Have you considered going into politics?

So go ahead and cite the evidence of the positive feedbacks necessary to amplify 1,1C of forcing to a 3C ECS?

 

[Surface Detail]

Well, that’s how Longview approaches science, so he thinks everyone does it that way.

Yes, it's quite bizarre. He really does appear to believe that scientists routinely decide on a result (or are given one by politicians) and then try to manipulate the data to obtain that result. If he had ever worked as a scientist or had any idea at all of how science works, he'd realise how utterly ridiculous that is. Yes, you do get the occasional fraud with an agenda, but these people are soon found out for what they are and are no longer taken seriously by their peers.

 

[Surface Detail]

So go ahead and cite the evidence of the positive feedbacks necessary to amplify 1,1C of forcing to a 3C ECS?

Published on 22 July 2020:

An assessment of Earth's climate sensitivity using multiple lines of evidence

"We assess evidence relevant to Earth's equilibrium climate sensitivity per doubling of atmospheric CO2, characterized by an effective sensitivity S . This evidence includes feedback process understanding, the historical climate record, and the paleoclimate record. An S value lower than 2 K is difficult to reconcile with any of the three lines of evidence. The amount of cooling during the Last Glacial Maximum provides strong evidence against values of S greater than 4.5 K. Other lines of evidence in combination also show that this is relatively unlikely. We use a Bayesian approach to produce a probability density (PDF) for S given all the evidence, including tests of robustness to difficult‐to‐quantify uncertainties and different priors. The 66% range is 2.6‐3.9 K for our Baseline calculation, and remains within 2.3‐4.5 K under the robustness tests; corresponding 5‐95% ranges are 2.3‐4.7 K, bounded by 2.0‐5.7 K (although such high‐confidence ranges should be regarded more cautiously). This indicates a stronger constraint on S than reported in past assessments, by lifting the low end of the range. This narrowing occurs because the three lines of evidence agree and are judged to be largely independent, and because of greater confidence in understanding feedback processes and in combining evidence. We identify promising avenues for further narrowing the range in S , in particular using comprehensive models and process understanding to address limitations in the traditional forcing‐feedback paradigm for interpreting past changes."

 

[Jack Hays]

Published on 22 July 2020:

An assessment of Earth's climate sensitivity using multiple lines of evidence

"We assess evidence relevant to Earth's equilibrium climate sensitivity per doubling of atmospheric CO2, characterized by an effective sensitivity S . This evidence includes feedback process understanding, the historical climate record, and the paleoclimate record. An S value lower than 2 K is difficult to reconcile with any of the three lines of evidence. The amount of cooling during the Last Glacial Maximum provides strong evidence against values of S greater than 4.5 K. Other lines of evidence in combination also show that this is relatively unlikely. We use a Bayesian approach to produce a probability density (PDF) for S given all the evidence, including tests of robustness to difficult‐to‐quantify uncertainties and different priors. The 66% range is 2.6‐3.9 K for our Baseline calculation, and remains within 2.3‐4.5 K under the robustness tests; corresponding 5‐95% ranges are 2.3‐4.7 K, bounded by 2.0‐5.7 K (although such high‐confidence ranges should be regarded more cautiously). This indicates a stronger constraint on S than reported in past assessments, by lifting the low end of the range. This narrowing occurs because the three lines of evidence agree and are judged to be largely independent, and because of greater confidence in understanding feedback processes and in combining evidence. We identify promising avenues for further narrowing the range in S , in particular using comprehensive models and process understanding to address limitations in the traditional forcing‐feedback paradigm for interpreting past changes."

Review article. Merely recycles other people's research. Published as paradigm defense. It's apparent ECS is the hill that AGW will die on.

 

[longview]

Published on 22 July 2020:

An assessment of Earth's climate sensitivity using multiple lines of evidence

"We assess evidence relevant to Earth's equilibrium climate sensitivity per doubling of atmospheric CO2, characterized by an effective sensitivity S . This evidence includes feedback process understanding, the historical climate record, and the paleoclimate record. An S value lower than 2 K is difficult to reconcile with any of the three lines of evidence. The amount of cooling during the Last Glacial Maximum provides strong evidence against values of S greater than 4.5 K. Other lines of evidence in combination also show that this is relatively unlikely. We use a Bayesian approach to produce a probability density (PDF) for S given all the evidence, including tests of robustness to difficult‐to‐quantify uncertainties and different priors. The 66% range is 2.6‐3.9 K for our Baseline calculation, and remains within 2.3‐4.5 K under the robustness tests; corresponding 5‐95% ranges are 2.3‐4.7 K, bounded by 2.0‐5.7 K (although such high‐confidence ranges should be regarded more cautiously). This indicates a stronger constraint on S than reported in past assessments, by lifting the low end of the range. This narrowing occurs because the three lines of evidence agree and are judged to be largely independent, and because of greater confidence in understanding feedback processes and in combining evidence. We identify promising avenues for further narrowing the range in S , in particular using comprehensive models and process understanding to address limitations in the traditional forcing‐feedback paradigm for interpreting past changes."

Um! you are mistaking someone's theory for evidence!
The paper is interesting, so I will look at what assumptions they used.
Error - Cookies Turned Off

 

[longview]

Published on 22 July 2020:

An assessment of Earth's climate sensitivity using multiple lines of evidence

"We assess evidence relevant to Earth's equilibrium climate sensitivity per doubling of atmospheric CO2, characterized by an effective sensitivity S . This evidence includes feedback process understanding, the historical climate record, and the paleoclimate record. An S value lower than 2 K is difficult to reconcile with any of the three lines of evidence. The amount of cooling during the Last Glacial Maximum provides strong evidence against values of S greater than 4.5 K. Other lines of evidence in combination also show that this is relatively unlikely. We use a Bayesian approach to produce a probability density (PDF) for S given all the evidence, including tests of robustness to difficult‐to‐quantify uncertainties and different priors. The 66% range is 2.6‐3.9 K for our Baseline calculation, and remains within 2.3‐4.5 K under the robustness tests; corresponding 5‐95% ranges are 2.3‐4.7 K, bounded by 2.0‐5.7 K (although such high‐confidence ranges should be regarded more cautiously). This indicates a stronger constraint on S than reported in past assessments, by lifting the low end of the range. This narrowing occurs because the three lines of evidence agree and are judged to be largely independent, and because of greater confidence in understanding feedback processes and in combining evidence. We identify promising avenues for further narrowing the range in S , in particular using comprehensive models and process understanding to address limitations in the traditional forcing‐feedback paradigm for interpreting past changes."

AS I suspected, the paper makes a number of assumptions.
The first is that the warming between the glacial period and the pre industrial temperature is 5K (5C).

Last Glacial to interglacial global mean temperature change estimates have been much
studied and remain debated. Across studies, the inferred range is between ~3 and ~7 K
below pre-industrial with little probability of lying outside this range
We therefore take N(-5,1) as our observational likelihood of the temperature change.

They then assume the greenhouse gas levels for the two periods,

Lower GHG concentrations are well characterized for the LGM. Here we use the latest
PMIP4/CMIP6 LGM estimates of [CO2] = 190 ppm, [CH4] = 375 ppb and [N2O] = 200 ppb
(Kageyama et al., 2017). For the pre-industrial greenhouse gases, we use the CMIP6 estimates for 1850 (Meinshausen et al., 2017),
[CO2] = 284 ppm, [CH4] = 808 ppb, and [N2O] = 273 ppb.

I am not saying the assumptions and estimates are wrong, only that they are all subject to debate, and have wide variation
on their own.
Next they assign forcing to the estimated changes.

The forcing formulae from Etminan et al. (2016) translate these concentrations
into CO2: -2.16W/m2, CH4: -.37W/m2, N2O: -.27W/m2.

In short, there are plenty of assumptions made, and this is not evidence.