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William
2011-Aug-20, 01:18 AM
This is an interesting paper.

Can we discuss this paper in the general science section?

On the Observational Determination of Climate Sensitivity and Its Implications

http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf



Here the statistical confidence intervals of the sensitivity estimate at 90%, 95%, and 99% levels are also calculated by the standard error of the feedback factor fTotal. This interval should prevent any problems arising from limited sampling. As a result, the climate sensitivity for a doubling of CO2 is estimated to be 0.7K (with the confidence interval 0.5K -1.3K at 99% levels). This observational result shows that model sensitivities indicated by the IPCC AR4 are likely greater than the possibilities estimated from the observations.



This modest warming is much less than current climate models suggest for a doubling of CO2. Models predict warming of from 1.5oC to 5oC and even more for a doubling of CO2. Model predictions depend on the ‘feedback’ within models from the more important greenhouse substances, water vapor and clouds. Within all current climate models, water vapor increases with increasing temperature so as to further inhibit infrared cooling. Clouds also change so that their visible reflectivity decreases, causing increased solar absorption and warming of the earth. Cloud feedbacks are still considered to be highly uncertain (IPCC, 2007), but the fact that these feedbacks are strongly positive in most models is considered to be an indication that the result is basically correct. Methodologically, this is unsatisfactory. Ideally, one would seek an observational test of the issue. Here we suggest that it may be possible to test the issue with existing data from satellites.


Moreover, as we will show later in this paper, the regression approach, itself, is an important source of bias. In a recent paper (Lindzen and Choi, 2009) we attempted to resolve these issues though, as has been noted in subsequent papers, the details of that paper were, in important ways, also incorrect (Chung et al., 2010; Murphy, 2010; Trenberth et al., 2010). There were four major criticisms to Lindzen and Choi (2009): (i) incorrect computation of climate sensitivity, (ii) statistical insignificance of the results, (iii) misinterpretation of air-sea interaction in the Tropics, (iv) misuse of uncoupled atmospheric models. The present paper responds to the criticism, and corrects the earlier approach where appropriate. The earlier results are not significantly altered, and we show why these results differ from what others like Trenberth et al. (2010), and Dessler (2010) obtain.


Moreover, we have shown why studies using simple regressions of ΔFlux on ΔSST serve poorly to determine feedbacks. To respond to the criticism of our emphasis on the tropical domain (Murphy, 2010; Trenberth et al., 2010), we analyzed the complete record of CERES for the globe (Dessler, 2010) (Note that ERBE data is not available for the high latitudes since the field-of-view is between 60oS and 60oN). As seen in the previous section, the use of the global CERES record leads to a result that is basically similar to that from the tropical data in this study. The global CERES record, however, contains more noise than the tropical record.



This result lends support to the argument that the water vapour feedback is primarily restricted to the tropics, and there are reasons to suppose that this is also the case for cloud feedbacks. Although, in principle, climate feedbacks may arise from any latitude, there are substantive reasons for supposing that they are, indeed, concentrated mostly in the tropics. The most prominent model feedback is that due to water vapor, where it is commonly noted that models behave roughly as though relative humidity were fixed. Pierrehumbert (2009) examined outgoing radiation as a function of surface temperature theoretically for atmospheres with constant relative humidity. His results are shown in Fig. 13.

William
2011-Aug-21, 04:34 PM
The IPCC predicted warming of 3.5C for a doubling of atmospheric C02 from 280 ppm to 560 ppm is predicated on the assumption that water vapor in the atmosphere will increase in the atmosphere with no net increase in cloud cover and short wave radiation reflected into space, to amplify the warming due to the increase in atmospheric CO2 which is referred to as positive feedback. This assumption is built into the general circulation models (GCM).

http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf



However, warming from a doubling of CO2 would only be about 1oC (based on simple calculations where the radiation altitude and the Planck temperature depend on wavelength in accordance with the attenuation coefficients of well mixed CO2 molecules; a doubling of any concentration in ppmv produces the same warming because of the logarithmic dependence of CO2’s absorption on the amount of CO2) (IPCC, 2007).

This modest warming is much less than current climate models suggest for a doubling of CO2. Models predict warming of from 1.5oC to 5oC and even more for a doubling of CO2. Model predictions depend on the ‘feedback’ within models from the more important greenhouse substances, water vapor and clouds. Within all current climate models, water vapor increases with increasing temperature so as to further inhibit infrared cooling. Clouds also change so that their visible reflectivity decreases, causing increased solar absorption and warming of the earth.

Cloud feedbacks are still considered to be highly uncertain (IPCC, 2007), but the fact that these feedbacks are strongly positive in most models is considered to be an indication that the result is basically correct. Methodologically, this is unsatisfactory. Ideally, one would seek an observational test of the issue. Here we suggest that it may be possible to test the issue with existing data from satellites.

If there is no feedback amplification an increase in atmospheric CO2 from 280 ppm to 560 ppm will result in warming of 1.2C. Lindzen and Choi’s analysis of satellite data from two different satellites indicates that cloud cover increases in the tropics which resists (referred to as negative feedback) rather than amplifies the warming due to the increased atmospheric CO2 such that a doubling of atmospheric CO2 will result in 0.7C warming rather than 3.5C.

As Lindzen and Choi note in their paper (see link above) the warming due to CO2 is logarithmic, each doubling of CO2 produces the same warming. An increase therefore of atmospheric CO2 from 560 ppm to 1120 ppm will result in 0.7C + 0.7C = 1.4C warming.


As a result, the climate sensitivity for a doubling of CO2 is estimated to be 0.7K (with the confidence interval 0.5K - 1.3K at 99% levels). This observational result shows that model sensitivities indicated by the IPCC AR4 are likely greater than the possibilities estimated from the observations.


It should be noted that the average atmospheric CO2 for most of the period life has been on this planet has average between 1200 ppm and 1500 ppm. The optimal level of CO2 for plant life is 1000 ppm to 1500 ppm. (Commercial greenhouses inject CO2 into greenhouses to increase growth and yield. )

If increases in atmospheric CO2 does not cause dangerous warming therefore the increase in atmospheric CO2 and temperature (most of the temperature increases occurs at higher latitudes.) will be beneficial to the biosphere.

As CO2 continues to rise and there are no realistic (fundamental technical/engineering issues have been ignored and have not been discussed in the general public, nuclear energy has been ruled out, practical nuclear energy options have not been considered due to commercial competition rather than long term net benefit. Reactor designs that use natural rather than enriched uranium & the thorium reactor. ) and/or affordable (limited by the amount of free cash Western Governments have to spend and the final cost based on the current proposed methods including costs to resolve fundamental technical issues which have not been included in any of the cost estimates) methods to stop the increase we will have an opportunity to see by observation if the Lindzen and Choi’s analysis is correct.

Trakar
2011-Aug-21, 06:38 PM
This is an interesting paper.

Can we discuss this paper in the general science section?

On the Observational Determination of Climate Sensitivity and Its Implications

http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf

Are you prepared to defend Lindzen's iris theory in its latest incarnation?

Torsten
2011-Aug-21, 06:41 PM
William:

I don't have the time or experience to delve into Lindzen and Choi (2011). I'll watch if others respond. However, I feel compelled to address this:


It should be noted that the average atmospheric CO2 for most of the period life has been on this planet has average between 1200 ppm and 1500 ppm. The optimal level of CO2 for plant life is 1000 ppm to 1500 ppm. (Commercial greenhouses inject CO2 into greenhouses to increase growth and yield. )

You've made this claim before based on practices in commercial greenhouses. You were shown at the time that for some species a high CO2 concentration induces boron deficiency (and IIRC calcium deficiency can be induced too). In a commercial greenhouse it is possible to provide the necessary fertilizers to mitigate the problem. We do not know the micronutrient-availability response to increased CO2 of even a small fraction of wild species or, I suspect, of most field commercial crops, and we don't have the resources to fertilize all the wild areas should induced deficiencies become an unwelcome reality.

Further, you were shown that for a number of rice varieties, the threshold temperature at which spikelet sterility occurs goes down with increasing CO2 concentration. To be clear on this, even in the absence of global warming, the current range of temperatures in rice growing areas can cause years in which serious crop reductions occur due to this lowering of threshold temperature, and the frequency of these events will rise due to the increasing CO2.

You were also shown that in general, when CO2 concentration is increased, the Nitrogen/Carbon ratio in foliage goes down for both C3 and C4 species. That is, the protein content of the forage eaten by herbivores is lower as the atmospheric concentration of CO2 rises.

This is serious stuff William. Why do you not mention it?

I'll take this opportunity to correct a statement I made the last time we discussed this (that thread was locked). I had incorrectly concluded that I had observed induced boron deficiency in lodgepole pine during the very hot spring we'd had that year. I followed up on it and was able to obtain micronutrient data from foliage samples for the affected and unaffected plots as well as being able to examine the growing tips and found that it was an insect causing the damage.

Trakar
2011-Aug-21, 06:41 PM
...It should be noted that the average atmospheric CO2 for most of the period life has been on this planet has average between 1200 ppm and 1500 ppm. The optimal level of CO2 for plant life is 1000 ppm to 1500 ppm. (Commercial greenhouses inject CO2 into greenhouses to increase growth and yield. )

If increases in atmospheric CO2 does not cause dangerous warming therefore the increase in atmospheric CO2 and temperature (most of the temperature increases occurs at higher latitudes.) will be beneficial to the biosphere.

As CO2 continues to rise and there are no realistic (fundamental technical/engineering issues have been ignored and have not been discussed in the general public, nuclear energy has been ruled out, practical nuclear energy options have not been considered due to commercial competition rather than long term net benefit. Reactor designs that use natural rather than enriched uranium & the thorium reactor. ) and/or affordable (limited by the amount of free cash Western Governments have to spend and the final cost based on the current proposed methods including costs to resolve fundamental technical issues which have not been included in any of the cost estimates) methods to stop the increase we will have an opportunity to see by observation if the Lindzen and Choi’s analysis is correct.

Is this thread about Lindzen's paper, or your own ATM considerations regarding optimal CO2 levels, alternative energy, and so forth?

tusenfem
2011-Aug-21, 07:35 PM
William, please decide which of the two topics you want to discuss in this thread, either the paper or your ideas about CO2 and plantlife.

William
2011-Aug-21, 09:51 PM
Understood Tusenfem.

This thread is to discuss Lindzen and Choi's 2011 paper. I will later this year come back to discuss plants and CO2.

William
2011-Aug-21, 09:52 PM
Is this thread about Lindzen's paper, or your own ATM considerations regarding optimal CO2 levels, alternative energy, and so forth?

This thread is to discuss Lindzen and Choi's paper.

William
2011-Aug-21, 10:48 PM
Are you prepared to defend Lindzen's iris theory in its latest incarnation?

This thread is not to discuss Lindzen and Choi's iris paper. This thread is to discuss Lindzen and Choi's feedback paper and the implication of the feedback paper if their conclusion is correct. It is a very important paper if the conclusion is correct.

http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf

I have read through the paper a couple of times. It seems to address the deficiencies other authors noted in past reviews of other papers written on this subject.

Lindzen and Choi analyzed (using both lead and lag analysis) satellite data (two different satellite data sets) and found that the tropical region's response to an increase in forcing is negative (cloud cover in the tropical region increases which results in an increase in short wave radiation reflection into space) which resists the forcing change.

Lindzen and Choi's analysis if correct indicates that a doubling of atmospheric CO2 from 280 ppm to 560 ppm will result in approximately 0.7C warming, with most of warming occurring at high latitudes.

It is suggested that 0.7C warming is not dangerous. From the standpoint of the biosphere and humanity it is a good thing rather than a bad thing if the conclusion in Lindzen and Choi's paper is correct.

Comment:
Lindzen, Spencer, and others involved in this research have all stated that conservation of energy and a reduction in wasteful consumption is logical. Is is suggested that the majority of people support that statement.

If Lindzen and Choi's analysis is correct there will likely be no significant additional warming in the next 20 years even though CO2 will continue to rise. For Lindzen and Choi's conclusion to be correct, a significant portion of the late 20th century warming would have had to be due to a different cause. Other observational evidence appears to leave the door open for Lindzen and Choi's conclusion to be possibly correct - the abatement of warming, the fact the majority of the late 20th century warming was in high latitudes in the Northern Hemisphere.

In science although it is possible to prove or disprove a hypothesis, it is not always obvious in advance of additional data to know which hypothesis is correct. As I have stated before I personally find this issue interesting as I believe I will in my lifetime find out which hypothesis is correct or in correct.

I am actively looking at the data and comparing it to the two hypotheses.

Tensor
2011-Aug-22, 02:36 AM
Other observational evidence appears to leave the door open for Lindzen and Choi's conclusion to be possibly correct - the abatement of warming,

What abatement of warming? Cites? Sources?


the fact the majority of the late 20th century warming was in high latitudes in the Northern Hemisphere.

Citations? Sources?

William
2011-Aug-22, 12:46 PM
What abatement of warming? Cites? Sources?



Citations? Sources?

Hi Tensor,

I owe you a reply, however, there will be a delay as I am out of the office this week and will be mountain climbing this weekend.

Strange
2011-Aug-22, 12:53 PM
...and will be mountain climbing this weekend.

Looking for somewhere cooler to live? :)
(http://www.bautforum.com/showthread.php/119825-Run-Away!-Critters-and-climate-change)

Trakar
2011-Aug-22, 05:33 PM
This thread is not to discuss Lindzen and Choi's iris paper. This thread is to discuss Lindzen and Choi's feedback paper and the implication of the feedback paper if their conclusion is correct. It is a very important paper if the conclusion is correct.

http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf

This "feedback" paper is simply a rehash of Lindzen's iris theory, employing most of the same mechanisms and postulates that have already been found deficient and flawed in the past several incarnations of the proposal,...so the question remains, are you prepared to defend this paper?

William
2011-Aug-22, 06:17 PM
What abatement of warming? Cites? Sources?



Citations? Sources?

Hi Tensor,

The following is in response to your question.

The first paper acknowledges there is an unexplained lack of warming which requires an explanation. The proposed SO2 from Chinese coal burning does not however explain the observations as noted by the second paper. (The problem is there is warming in the Northern Hemisphere and cooling in the Southern Hemisphere. As the SO2 is produced in the Northern Hemisphere and there is little exchange of northern and southern hemisphere aerosol particles the Chinese SO2 emission cannot explain the observation.

One issue with the analysis to explain the lack of warming is it assumes the feedback is positive rather than negative.

The point is there is an acknowledge lack of warming which as I said leaves the door open for Lindzen and Choi's conclusion that the planet's feedback response to a change in forcing is negative (clouds in the tropical region increase in reflecting more short wave radiation into space which resists the forcing change) rather than positive (increased water vapor in the tropical region results in amplification of the CO2 forcing.


http://wattsupwiththat.files.wordpress.com/2011/07/pnas-201102467.pdf

Reconciling anthropogenic climate change with
observed temperature 1998–2008

Given the widely noted increase in the warming effects of rising greenhouse gas concentrations, it has been unclear why global surface temperatures did not rise between 1998 and 2008. We find that this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings. Declining solar insolation as part of a normal eleven-year cycle, and a cyclical change from an El Nino to a La Nina dominate our measure of anthropogenic effects because rapid growth in short-lived sulfur emissions partially offsets rising greenhouse gas concentrations. As such, we find that recent global temperature records are consistent with the existing understanding of the relationship among global surface temperature, internal variability, and radiative forcing, which includes anthropogenic factors with well known warming and cooling effects.

http://www.agu.org/pubs/crossref/2011/2011GL047563.shtml

Major influence of tropical volcanic eruptions on the stratospheric aerosol layer during the last decade

The variability of stratospheric aerosol loading between 1985 and 2010 is explored with measurements from SAGE II, CALIPSO, GOMOS/ENVISAT, and OSIRIS/Odin space-based instruments. We find that, following the 1991 eruption of Mount Pinatubo, stratospheric aerosol levels increased by as much as two orders of magnitude and only reached “background levels” between 1998 and 2002. From 2002 onwards, a systematic increase has been reported by a number of investigators. Recently, the trend, based on ground-based lidar measurements, has been tentatively attributed to an increase of SO2 entering the stratosphere associated with coal burning in Southeast Asia. However, we demonstrate with these satellite measurements that the observed trend is mainly driven by a series of moderate but increasingly intense volcanic eruptions primarily at tropical latitudes. These events injected sulfur directly to altitudes between 18 and 20 km. The resulting aerosol particles are slowly lofted into the middle stratosphere by the Brewer-Dobson circulation and are eventually transported to higher latitudes.

William
2011-Aug-22, 06:25 PM
This "feedback" paper is simply a rehash of Lindzen's iris theory, employing most of the same mechanisms and postulates that have already been found deficient and flawed in the past several incarnations of the proposal,...so the question remains, are you prepared to defend this paper?

Trakar,

Lindzen and Choi present detailed analysis of two sets of satellite data to support their conclusion. As I said, I read through their paper a couple of times. It seemed to address the problems raised by other critical reviewers who are experts in this field.

The fact that the climate does not oscillate when large forcing changes such a large equatorial volcanic eruption occurs supports the assertion that the feedback response is negative rather than positive.

As I said, it is good thing rather than a bad thing if the feedback response is negative rather than positive.

I think we are waiting for a published paper that refutes their finding. And as I said, if Lindzen and Choi's finding is correct is unlikely there will be any significant warming in future.

William
2011-Aug-22, 06:34 PM
Looking for somewhere cooler to live? :)
(http://www.bautforum.com/showthread.php/119825-Run-Away!-Critters-and-climate-change)

Last weekend, I spent time with a guide climbing mountain glaciers. The guide noted the glaciers had retreated in the 20th century.

Interesting the retreating mountain glaciers exposed tree stumps that were dated to have been living 8000 years ago which is the warmest period in the Holocene interglacial period. What is interesting is there are no trees growing in that region now. There have been two very large back to back high snow falls and cold summers in the mountains where I climb. On a number of peaks the winter snow did not melt and there will definitely be an increase in ice on the mountain glaciers. Two years does not a trend make however it is interesting. Something caused the Little Ice Age and the Medieval warm period.

If Lindzen and Choi's conclusion is correct something else caused a significant portion of the late 20th century warming. If there is cooling that would support Lindzen and Choi's conclusion.

Trakar
2011-Aug-22, 06:52 PM
Hi Tensor,

The following is in response to your question.


http://wattsupwiththat.files.wordpress.com/2011/07/pnas-201102467.pdf


You are citing a partisan political blog as the source of your information regarding an asserted climate change hiatus!?! SERIOUSLY???!

Addendum: I see now that you merely referenced the blogs mirroring of this paper ("Reconciling anthropogenic climate change with
observed temperature since 1998" - http://www.economics.harvard.edu/faculty/stock/files/PNAS_SI_Apendix_Final.pdf)
on their site, still nothing good can come from trying to understand science from a site dedicated to misrepresenting and distorting science,...however, and more to the point of your reference, your focus on the words "...this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings..." you miss the findings of paper which state:

...The 1998-2008 hiatus is not the first period in the instrumental temperature record when the effects of anthropogenic changes in greenhouse gases and sulfur emissions on radiative forcing largely cancel. In-sample simulations indicate that temperature does not rise between the 1940’s and 1970’s because the cooling effects of sulfur emissions rise slightly faster than the warming effect of greenhouse gases. The post 1970 period of warming, which constitutes a significant portion of the increase in global surface temperature since the mid 20th century, is driven by efforts to reduce air pollution in general and acid deposition in particular, which cause sulfur emissions to decline while the concentration of greenhouse gases continues to rise (7).
The results of this analysis indicate that observed temperature after 1998 is consistent with the current understanding of the relationship among global surface temperature, internal variability, and radiative forcing, which includes anthropogenic factors that have well known warming and cooling effects...

Trakar
2011-Aug-22, 07:19 PM
This "feedback" paper is simply a rehash of Lindzen's iris theory, employing most of the same mechanisms and postulates that have already been found deficient and flawed in the past several incarnations of the proposal,...so the question remains, are you prepared to defend this paper?

Trakar,

Lindzen and Choi present detailed analysis of two sets of satellite data to support their conclusion. As I said, I read through their paper a couple of times. It seemed to address the problems raised by other critical reviewers who are experts in this field.


Which critical reviewers and problems are you speaking of specifically? Merely the ones hand-waved away in Lindzen's latest version of his "paper," or have you actually researched and come to an understanding of the broad scale problems and fundemental misunderstandings at the roots of the problem with Lindzen's Iris theory?



The fact that the climate does not oscillate when large forcing changes such a large equatorial volcanic eruption occurs supports the assertion that the feedback response is negative rather than positive.


Volcanic impacts upon short term climate are largely determined by type of eruption and composition of eruption gases. If you are aware of "a large equitorial volcanic eruption" which should have caused climate impact (ie, an explosive stratovolcano eruption that pushed large amounts of particulate and sulphur compounds deep into the stratosphere) but did not cause any short-term fluctuations please cite and reference them.

(though technically, this issue is irrelevent and not discussed in Lindzen's paper,...so again are we talking about the paper, or your own particular ATM climate considerations?)

William
2011-Aug-22, 11:50 PM
You are citing a partisan political blog as the source of your information regarding an asserted climate change hiatus!?! SERIOUSLY???!

Addendum: I see now that you merely referenced the blogs mirroring of this paper ("Reconciling anthropogenic climate change with
observed temperature since 1998" - http://www.economics.harvard.edu/faculty/stock/files/PNAS_SI_Apendix_Final.pdf)
on their site, still nothing good can come from trying to understand science from a site dedicated to misrepresenting and distorting science,...however, and more to the point of your reference, your focus on the words "...this hiatus in warming coincides with a period of little increase in the sum of anthropogenic and natural forcings..." you miss the findings of paper which state:

Trakar,

I provided a link to a paper that is stored at a blog. The link is to a paper not to a blog. I fail to see the logic or reason of your comment.

The paper acknowledges a fact. The warming has stopped. There are actually two papers which attempt to explain the hiatus in warming.

Where have you been. As time goes by and there is no warming an explanation is required.

The second paper notes satellite data shows short wave radiation reflected into space in the tropics increased during the period when there was a lack of warming. That finding is in agreement with Lindzen and Choi's paper. The disagreement is on cause.

William
2011-Aug-23, 12:02 AM
Which critical reviewers and problems are you speaking of specifically? Merely the ones hand-waved away in Lindzen's latest version of his "paper," or have you actually researched and come to an understanding of the broad scale problems and fundemental misunderstandings at the roots of the problem with Lindzen's Iris theory?



Volcanic impacts upon short term climate are largely determined by type of eruption and composition of eruption gases. If you are aware of "a large equitorial volcanic eruption" which should have caused climate impact (ie, an explosive stratovolcano eruption that pushed large amounts of particulate and sulphur compounds deep into the stratosphere) but did not cause any short-term fluctuations please cite and reference them.

(though technically, this issue is irrelevent and not discussed in Lindzen's paper,...so again are we talking about the paper, or your own particular ATM climate considerations?)

Trakar,

Check out a book on control systems. Systems that have positive feedback are unstable. They oscillate when there is a step input into the system. As noted in Lindzen and Choi's paper the response of some of the models was infinite.

Please do not accuse me of ATM because of your lack of understanding of an issue. It seems to me that you are trying to use the term ATM and writing in capitals as a method of argument. I presented the papers because there are interesting scientifically.

I have no problem discussing Lindzen and Choi's paper however I am not a specialist in that area. I noted I read the paper a couple of times. I provided a link to two papers which both acknowledge that there has been hiatus in warming.

Does that prove Lindzen and Choi are correct? No as I said, it seems to me, that finding leaves the door open for their conclusion to be correct.

Torsten
2011-Aug-23, 03:32 AM
The paper acknowledges a fact. The warming has stopped. There are actually two papers which attempt to explain the hiatus in warming.

Where have you been. As time goes by and there is no warming an explanation is required.


William:

Check out WoodForTrees (http://www.woodfortrees.org/plot/uah/from:1978/to:1998/trend/plot/uah/from:1998/to:2011/trend/plot/uah). I've pulled up your favourite temperature data source, UAH, and compared trends over selected periods (I've started the process in that link for you).

The following eight images are selected trend periods over the entire history of that data set as recorded at that site today. Many climate skeptics have been fond of using 1998 as the breakpoint year for comparing trends in order to make the recent trend look weak, but you can see that it doesn't really matter. The problem with the notion of a hiatus is that the period these people were pointing to is short. Also, and this is important, note we just came through one of the stongest La Niña events on record (http://www.bom.gov.au/climate/enso/feature/ENSO-feature.shtml) and are currently ENSO neutral (http://www.bom.gov.au/climate/enso/). (These links will change over time as the features they describe are updated.)

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break1997.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break1998.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break1999.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break2000.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break2001.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break2002.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break2003.png

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_at_WoodForTrees_20110822_Break2004.png

Tensor
2011-Aug-23, 04:29 AM
Hi Tensor,

The following is in response to your question.

The first paper acknowledges there is an unexplained lack of warming which requires an explanation. The proposed SO2 from Chinese coal burning does not however explain the observations as noted by the second paper.

What observations? All I get from the link for the second paper is the abstract. No conclusions, no in depth discussion, just the abstract. Where exactly in that abstract does it talk about the observations of the second paper? If you are going to present a paper to support your assertions, at least give us a link to the paper itself, not just to the abstract, which doesn't have any of the calculations, discussions, methods or other things that can be used to evaluate the paper.


(The problem is there is warming in the Northern Hemisphere and cooling in the Southern Hemisphere.

Cooling in the Southern Hemisphere? I suggest you look at Fawcett and Jones (http://www.aussmc.org/documents/waiting-for-global-cooling.pdf) Not to mention this graph (http://data.giss.nasa.gov/gistemp/graphs/Fig.A3.gif). Where in that graph indicates that the Souther Hemisphere has been cooling? Or perhaps you can refute Hansen et al 2010: Global surface temperature change (http://magician.ucsd.edu/~ltauxe/PmagSeminar/miscellaneous/hanson10.pdf)


As the SO2 is produced in the Northern Hemisphere and there is little exchange of northern and southern hemisphere aerosol particles the Chinese SO2 emission cannot explain the observation.

As you can see in the Fawcett and Jones paper, the Hansen paper, and the graph, there is no "observation" as you claimed. What there was, was a El Nino in 1998. A very strong one. This led to an extremely high mean temperature for the year.

If you compare that one year anomaly with the temperature in 2008 (a year with a strong La Nina) 2008 was a bit cooler than that 1998 anomaly. Not by much, and if you are only comparing the mean temperature for 1998 with 2008, yes it appears that there could be a slight cooling. But, that ignores all the data around 2008. That 1998 was from .3C warmer than 1997 or 1999, you realize what an anomaly 1998 was.

On top of that, 2008 was .2 C cooler than 2007 and 2009, yet it was almost as warm as 1998. 2005, 2006, 2007, 2009 and 2010 were all warmer than 1998 and the five year mean in 2010 was .3 C warmer than 1998.


One issue with the analysis to explain the lack of warming is it assumes the feedback is positive rather than negative.

Yeah, where in those papers or graph is a lack of warming?


The point is there is an acknowledge lack of warming

No there isn't. There are some local variations, but overall, it's still rising. From the Hansen paper.

"We suggest use of 12-month (and n×12) running mean temperature to fully remove the annual cycle and improve information content in temperature graphs. We conclude that global temperature continued to rise rapidly in the past decade, despite large year-to-year fluctuations associated with the El Niño-La Niña cycle of tropical ocean temperature. Record high global temperature during the period with instrumental data was reached in 2010."

Exactly what in that paragraph would lead you to believe that warming had stopped since 1998? Do you have any data, supported by observations, that support this? Something like that graph I linked to, or something along the line of that Hansen paper would be handy. And, if there is cooling, why was 2010 the hottest year (along with the four of the previous five years) since instrumentation?


which as I said leaves the door open for Lindzen and Choi's conclusion that the planet's feedback response to a change in forcing is negative (clouds in the tropical region increase in reflecting more short wave radiation into space which resists the forcing change) rather than positive (increased water vapor in the tropical region results in amplification of the CO2 forcing.

That door doesn't even have a crack in it. Unless, of course, you can show that Hansen's graphs are somehow wrong. Those two papers were what I could find in five minutes of looking. I could probably find more if you want.

On another note, Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?


ETA: I see torsten beat me to it with the El Nino and La Nina events.

Geo Kaplan
2011-Aug-23, 05:01 AM
Trakar,

Check out a book on control systems. Systems that have positive feedback are unstable. They oscillate when there is a step input into the system.

This is simplified to the point of being wrong. Positive feedback does not guarantee instability (here defined as the system possessing positive-real eigenvalues). Even if instability happens to result, the step response need not be oscillatory (if the eigenvalues are purely real, the state evolves exponentially, with no oscillation). Finally, instability need not lead to infinite growth; all real systems have nonlinearities that bound the response. One could get a limit cycle about some average steady-state value, or simply get stuck at some extremum, or a rich variety of other possible responses, depending on the details of the system's dynamical characteristics.

William
2011-Aug-23, 11:54 PM
William:

Check out WoodForTrees (http://www.woodfortrees.org/plot/uah/from:1978/to:1998/trend/plot/uah/from:1998/to:2011/trend/plot/uah). I've pulled up your favourite temperature data source, UAH, and compared trends over selected periods (I've started the process in that link for you).

The following eight images are selected trend periods over the entire history of that data set as recorded at that site today. Many climate skeptics have been fond of using 1998 as the breakpoint year for comparing trends in order to make the recent trend look weak, but you can see that it doesn't really matter. The problem with the notion of a hiatus is that the period these people were pointing to is short. Also, and this is important, note we just came through one of the stongest La Niña events on record (http://www.bom.gov.au/climate/enso/feature/ENSO-feature.shtml) and are currently ENSO neutral (http://www.bom.gov.au/climate/enso/). (These links will change over time as the features they describe are updated.)



The following is a paper co-authored by Michael Mann.

http://wattsupwiththat.files.wordpress.com/2011/07/pnas-201102467.pdf


Reconciling anthropogenic climate change with observed temperature 1998–2008 by Robert K. Kaufmann, Heikki Kauppi, Michael L. Mann, and James H. Stock

Data for global surface temperature indicate little warming between 1998 and 2008 (1). Furthermore, global surface temperature declines 0.2 °C between 2005 and 2008. Although temperature increases in 2009 and 2010, the lack of a clear increase in global surface temperature between 1998 and 2008 (1), combined with rising concentrations of atmospheric CO2 and other greenhouse gases, prompts some popular commentators (2, 3) to doubt the existing understanding of the relationship among radiative forcing, internal variability, and global surface temperature. This seeming disconnect may be one reason why the public is increasingly sceptical about anthropogenic climate change (4).

I agree the period of time for which there is alleged to be warming is short. The period of time for which there has been a hiatus in warming is also short. There is no observed warming prior to around 1994.

It is not clear looking at the past temperature trends and comparing what is observed to temperature changes during the holocene that this current period is evidence of positive feedback AGW as opposed to negative feedback AGW.

Lindzen and Choi's paper is a detailed analysis of two different sets of satellite data using lead and lag analysis. There analysis seems to confirm the planetary feedback is negative rather than positive. As I said, I am not a specialist in that field, however, based on what they have written in the paper it seems they have addressed past reviewers criticisms of there previously published paper.

As I noted, the climate response to a step forcing is consistent with negative feedback. A system with positive feedback will oscillate due to over correction above and below its equilibrium point when it is disturbed by a step forcing change. That is not what is observed when there is a large change due to a volcanic eruption.

William
2011-Aug-24, 12:00 AM
What observations? All I get from the link for the second paper is the abstract. No conclusions, no in depth discussion, just the abstract. Where exactly in that abstract does it talk about the observations of the second paper? If you are going to present a paper to support your assertions, at least give us a link to the paper itself, not just to the abstract, which doesn't have any of the calculations, discussions, methods or other things that can be used to evaluate the paper.






That door doesn't even have a crack in it. Unless, of course, you can show that Hansen's graphs are somehow wrong. Those two papers were what I could find in five minutes of looking. I could probably find more if you want.

On another note, Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?


ETA: I see torsten beat me to it with the El Nino and La Nina events.

Tensor,

See the link above to the paper co-authored by Michael Mann. Note the comment in that paper.

The issue is does the observed warming support positive feedback AGW vs negative feedback AGW.

As I said the observations current compared to past over a longer period (say the entire holocene period) leaves the door open for Lindzen and Choi's conclusion that the planet's feedback response is negative rather than positive.

Do you disagree with that statement?

Tensor
2011-Aug-24, 01:33 AM
Tensor, See the link above to the paper co-authored by Michael Mann. Note the comment in that paper.

I did. I read it. I also pointed out a problem with it and asked you specific questions about that paper that you say supports your claims. How about you answer the specific questions I asked?


The issue is does the observed warming support positive feedback AGW vs negative feedback AGW.

NO, it's not. You are moving the goalposts. You made specific claims that you said have to be in effect for the Choi paper to be valid for your claimed purpose. For your claims to have any merit, there has to be cooling. You don't have cooling, if yearly variation is taken out. I provided specific papers and graphs, along with explanations that refute your claims. You have not shown my refutations to be wrong (you haven't even bother to answer the questions I posed to you) So the Choi paper is is not valid for the purpose you are claiming for it. You made the claims in post #9. I asked you to support those claims in post #10. And this brings us to post #14.


As I said the observations current compared to past over a longer period (say the entire holocene period) leaves the door open for Lindzen and Choi's conclusion that the planet's feedback response is negative rather than positive.

So let's look at post #14. You presented two papers in Post #14. Neither of the papers mention the Holocene. As a matter of fact, you do not mention the holocene in any of your posts, except to note the age of tree stumps found from retreating glaciers, in post #16.

So, you did not say current compared to the past over a longer period. You just said a hiatus in warming. Then, when asked to provide support for that, you present a paper that details the temperature for the last ten years, but does not indicate if any of the years compared were anomalously high or low. And then don't even present a second paper, just a link to the abstract.


Do you disagree with that statement?

Since you haven't provided any support for any of your previous statements nor this statement. Yes, I do disagree with it.

Now, shall we go through the claims and questions in post #14, which you have seemingly ignored:


From Post #14 The first paper acknowledges there is an unexplained lack of warming which requires an explanation. The proposed SO2 from Chinese coal burning does not however explain the observations as noted by the second paper.

1. What observations? All I get from the link for the second paper is the abstract. No conclusions, no in depth discussion, just the abstract. Where exactly in that abstract does it talk about the observations of the second paper?


From Post #14 (The problem is there is warming in the Northern Hemisphere and cooling in the Southern Hemisphere.

2. Cooling in the Southern Hemisphere? I suggest you look at Fawcett and Jones (http://www.aussmc.org/documents/waiting-for-global-cooling.pdf) Not to mention this graph (http://data.giss.nasa.gov/gistemp/graphs/Fig.A3.gif) . Where in that graph indicates that the Souther Hemisphere has been cooling? Or perhaps you can refute Hansen et al 2010: Global surface temperature change (http://magician.ucsd.edu/~ltauxe/PmagSeminar/miscellaneous/hanson10.pdf)


From Post #14 One issue with the analysis to explain the lack of warming is it assumes the feedback is positive rather than negative.

3. Yeah, you've been saying this, but as you can see in the Fawcett and Jones paper, the Hansen paper, and the graph, there is no "observation" as you claimed. What there was, was a El Nino in 1998. A very strong one. This led to an extremely high mean temperature for the year.

If you compare that one year anomaly with the temperature in 2008 (a year with a strong La Nina) 2008 was a bit cooler than that 1998 anomaly. Not by much, and if you are only comparing the mean temperature for 1998 with 2008, yes it appears that there could be a slight cooling. But, that ignores all the data around 2008. That 1998 was from .3C warmer than 1997 or 1999, you realize what an anomaly 1998 was.

On top of that, 2008 was .2 C cooler than 2007 and 2009, yet it was almost as warm as 1998. 2005, 2006, 2007, 2009 and 2010 were all warmer than 1998 and the five year mean in 2010 was .3 C warmer than 1998. Where in those two papers or in that graph is there a lack of warming?


From Post #14 The point is there is an acknowledge lack of warming

4. No there isn't. There are some local variations, but overall, it's still rising. From the Hansen paper.

"We suggest use of 12-month (and n×12) running mean temperature to fully remove the annual cycle and improve information content in temperature graphs. We conclude that global temperature continued to rise rapidly in the past decade, despite large year-to-year fluctuations associated with the El Niño-La Niña cycle of tropical ocean temperature. Record high global temperature during the period with instrumental data was reached in 2010."

Exactly what in that paragraph would lead you to believe that warming had stopped since 1998? Do you have any data, supported by observations, that support this? Something like that graph I linked to, or something along the line of that Hansen paper would be handy. And, if there is cooling, why was 2010 the hottest year (along with the four of the previous five years) since instrumentation?


5. On another note, Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?

Torsten
2011-Aug-24, 02:11 AM
I agree the period of time for which there is alleged to be warming is short. The period of time for which there has been a hiatus in warming is also short. There is no observed warming prior to around 1994.


If you came to this conclusion by examining a trend using WoodForTrees for the period 1978-1994, then you should realize that the period includes all the observations during 1978 to the last one in 1993. Aerosols released by the June 1991 eruption of Mt Pinatubo remained airborne until at least the end of 1993 (The Atmospheric Impact of the 1991 Mount Pinatubo Eruption (http://pubs.usgs.gov/pinatubo/self/index.html)). I think you are familiar with the effects of that volcano's eruption. So it shouldn't come as a surprise that a temperature effect of -0.5C to -0.7C would drag that trend down.

William
2011-Aug-24, 03:51 AM
This is simplified to the point of being wrong. Positive feedback does not guarantee instability (here defined as the system possessing positive-real eigenvalues). Even if instability happens to result, the step response need not be oscillatory (if the eigenvalues are purely real, the state evolves exponentially, with no oscillation). Finally, instability need not lead to infinite growth; all real systems have nonlinearities that bound the response. One could get a limit cycle about some average steady-state value, or simply get stuck at some extremum, or a rich variety of other possible responses, depending on the details of the system's dynamical characteristics.

The vast majority of physical control system have negative feedback. Yes real system have nonlinearities and deadbands which makes a system with negative feedback potentially unstable in that it will oscillated until the system reaches saturation.

I do not have experience with systems that have positive feedback. There are not used for control systems as they are inherently unstable. They will oscillate rather than maintain a fixed control set point resisting strong step changes.

The observational data of the climate system seems to me based on my experience and training to support Lindzen and Choi's finding that the planetary response to a forcing change in the tropics is negative (atmosphere in the tropics is saturated increased forcing results increased cloud cover which results in increased short wave radiation that is reflected into space which resists the forcing change.)

William
2011-Aug-24, 04:07 AM
If you came to this conclusion by examining a trend using WoodForTrees for the period 1978-1994, then you should realize that the period includes all the observations during 1978 to the last one in 1993. Aerosols released by the June 1991 eruption of Mt Pinatubo remained airborne until at least the end of 1993 (The Atmospheric Impact of the 1991 Mount Pinatubo Eruption (http://pubs.usgs.gov/pinatubo/self/index.html)). I think you are familiar with the effects of that volcano's eruption. So it shouldn't come as a surprise that a temperature effect of -0.5C to -0.7C would drag that trend down.

Torsten,

You are starting with the assumption that the feedback response is positive. The satellite data analyzed by Lindzen and Choi does not support that assumption. Why? What suddenly changed post 1994 to cause the warming?

To me those advocating positive feedback which is required for the extreme AGW hypothesis to be correct seem to not be able to see the data independent from the hypothesis.

The climate in the past has most certainly cycled based on an analysis of the proxy data and the historical record of people who lived during those times.

Something not CO2 caused that cyclic climate change. The 20th century warming has not exceed the past cyclic warmest periods. Instrumentation is roughly 150 years.

As I stated, if Lindzin and Choi are correct there will likely be no additional warming and there will likely be cooling. That is the significance of their findings.

I do not see any data or analysis presented to support positive feedback and extreme AGW warming. To me it seems any warming is being used to advocate positive feedback and extreme AGW warming.

William
2011-Aug-24, 04:30 AM
I did. I read it. I also pointed out a problem with it and asked you specific questions about that paper that you say supports your claims. How about you answer the specific questions I asked?


NO, it's not. You are moving the goalposts. You made specific claims that you said have to be in effect for the Choi paper to be valid for your claimed purpose. For your claims to have any merit, there has to be cooling. You don't have cooling, if yearly variation is taken out. I provided specific papers and graphs, along with explanations that refute your claims. You have not shown my refutations to be wrong (you haven't even bother to answer the questions I posed to you) So the Choi paper is is not valid for the purpose you are claiming for it. You made the claims in post #9. I asked you to support those claims in post #10. And this brings us to post #14.


So let's look at post #14. You presented two papers in Post #14. Neither of the papers mention the Holocene. As a matter of fact, you do not mention the holocene in any of your posts, except to note the age of tree stumps found from retreating glaciers, in post #16.

Yes, I do disagree with it.



Tensor,

Stop stating this is my ATM theory. I assume you are doing that to bolster a non existing counter scientific argument.

I provided a link to a paper written by a specialist in this field that analyzes satellite data that indicates the tropical response to a change in forcing is negative. (Clouds in the tropical region increase which results in increased short wave radiation reflected into space). Negative feedback resists forcing changes. Positive feedback amplifies forcing changes. Lindzen and Choi provide further analysis that indicates past analysis methods were flawed and would have erroneously indicated positive feedback. I acknowledge that I am not a specialist in this field. I read Lindzen and Choi's paper and it seems convincing to me, I believe I understand the implications if their conclusion is correct.

Yes, if Lindzen and Choi are correct the planet will likely significantly cool. Has it yet. No. I agree it has not significantly cooled yet. We are in agreement concerning that statement.

Did I say we need to wait for more data to definitively know which hypothesis is correct?

As I noted sometimes it is not clear which hypothesis is correct or incorrect in advance of the new data. In the case of the problem I believe we will find out which hypothesis is or is not correct.

Torsten
2011-Aug-24, 06:39 AM
You are starting with the assumption that the feedback response is positive.
How do you get that? That does not follow. It is illogical. No, I am merely pointing out that you are incorrect in saying there was no warming prior to 1994. I used UAH for your benefit because it's a product you've stated you believe is superior to the others (it's not), and it covered the time period skeptics point to when they say warming has stopped. But I'm finding it hard to believe that you would actually make a statement as general as saying that there was no warming before 1994 based on that short record. Did you not think to consider looking at the trends recorded in GISTEMP or HADCRUT3? You've been shown previously that the satellites and the GISTEMP or HADCRUT3 match one another fairly well for the period where they overlap. Why wouldn't you check other data before making such a misleading statement?



The satellite data analyzed by Lindzen and Choi does not support that assumption. Why? What suddenly changed post 1994 to cause the warming?

Nothing "suddenly" changed after 1994. Read what I wrote above. For you to now repeat that the post-1994 temperature was somehow mysterious suggests that you don't accept the Pinatubo explanation. Is this true?

captain swoop
2011-Aug-24, 10:34 AM
William

What Exactly is your ATM Claim within the rules of the ATM Forum?
State it in your next post.
Then, as per the rules for the ATM Forum answer questions and provide support, not vague links to papers.

Swift
2011-Aug-24, 01:20 PM
Stop stating this is my ATM theory. I assume you are doing that to bolster a non existing counter scientific argument.

I'll add a further note: whether you created the theory or someone else did, you are presenting it on BAUT and therefore it is your complete responsibility to defend it. And as long as we keep this thread in ATM, it is our determination that it an ATM theory and you are wholely responsible for all the obligations of defending it.

If you do not wish to follow these obligations, state so immediately, and this thread will be closed.

Swift
2011-Aug-24, 03:12 PM
The thread closure was accidental

Geo Kaplan
2011-Aug-24, 05:34 PM
The vast majority of physical control system have negative feedback. Yes real system have nonlinearities and deadbands which makes a system with negative feedback potentially unstable in that it will oscillated until the system reaches saturation.

I do not have experience with systems that have positive feedback. There are not used for control systems as they are inherently unstable. They will oscillate rather than maintain a fixed control set point resisting strong step changes.

Your knowledge and understanding of feedback in general are far too weak for you to make any strong assertions regarding climate change models. Nonlinearities and deadbands are not the common source of instability in negative feedback systems. If you simply follow your own advice to "open any book on control theory" you would discover that time delay (in effect) is by far the largest problem. Look for terms such as "phase margin" to learn more about this problem in a classical control context.

Your assertions about positive feedback are similarly ill-founded. Positive feedback per se does not guarantee instability, just as negative feedback does not guarantee stability. Furthermore, instability need not be associated with oscillatory transient response (consider an inverted pendulum merely tipping over from the vertical; oscillation is not guaranteed). Conflating oscillatory transient behavior with positive feedback is a dangerous error. Both negative and positive feedback (and systems with no feedback -- as in a mass on a spring) can exhibit oscillatory, damped, undamped or purely exponential responses (both growth and decay). Additional information is needed to deduce the nature of the system; an output behavior by itself is not sufficient.

If you're going to mount a serious defense of ideas that depend fundamentally on system dynamical behavior, you're going to have to arm yourself much better.

"Get thee to a library."

William
2011-Aug-24, 10:07 PM
William

What Exactly is your ATM Claim within the rules of the ATM Forum?
State it in your next post.
Then, as per the rules for the ATM Forum answer questions and provide support, not vague links to papers.

The first comment in this thread has a request to discuss Lindzen and Choi's paper in the general science section. This comment was placed in the ATM section as comments I made in the science section were labelled ATM and I has given an infraction.

Lindzen and Choi analyzed satellite data from two satellites using lead and lag analysis. The finding is that tropical region's response to an increase in forcing is an increase in cloud cover which reflects more short wave radiation into space which resists initial forcing which is referred to as negative feedback. The IPCC model's assume the
feedback response to a change in forcing is positive which means the planet amplifies the response.

I can explain or discuss the Lindzen and Choi's paper. Lindzen and Choi are specialists in this field. Their analysis includes a theoretical mathematical analysis that shows how the regression analysis technique used by other scientists will result in a result that indicates the feedback is positive when it is in fact negative. Lindzen and Choi's paper includes, discusses, and addresses past criticisms of their past paper on this subject.

Lindzen and Choi calculated based on their findings that the planet will warm roughly 0.7C for a doubling of atmospheric CO2 rather than the 3.5C predicted by the IPCC. The IPCC 3.5C requires that the feedback response be positive and amplify the initial forcing.


If the Lindzen and Choi's finding is correct a significant portion of the late twentieth century warming was due to something else rather than AGW. I noted I agree with Torsten's comment that short term hiatus in warming is not sufficient observational evidence to prove Lindzen and Choi's finding is correct. Definitive proof would be some cooling and no long term significant warming. (i.e. The total warming due to a doubling of atmospheric CO2 is 0.7C, therefore there must be a roll back and little future warming if the planetary feedback response is negative.)


The other papers I quoted and the discussion on how the response is different for systems that have negative rather than positive feedback is logical support for Lindzen and Choi's paper but not proof. Logical support is different than definitive proof.

(i.e. A paper that note there has been a short term hiatus in warming is acknowledging the start of trend that must necessarily continue on a long term basis if Lindzen and Choi's conclusion is correct.)


The first published paper that include Michael Mann as a co-author hypothesized that the lack of warming as due to an increase in Chinese SO2.

The second paper noted the lack of warming can be explained by an increase in short wave radiation reflected into space which is consistent with Lindzen and Choi's finding. The second paper appealed to an increase in volcanic eruptions in the tropics as the cause of the increase in tropic short wave radiation that is reflected into space.

Currently those advocating extreme AGW attributed all of the late 20th century warming to AGW.

I will discuss the issue of expected oscillatory response to a step forcing change for positive feedback in the next comment.

William
2011-Aug-24, 10:32 PM
Your knowledge and understanding of feedback in general are far too weak for you to make any strong assertions regarding climate change models. Nonlinearities and deadbands are not the common source of instability in negative feedback systems. If you simply follow your own advice to "open any book on control theory" you would discover that time delay (in effect) is by far the largest problem. Look for terms such as "phase margin" to learn more about this problem in a classical control context.

Your assertions about positive feedback are similarly ill-founded. Positive feedback per se does not guarantee instability, just as negative feedback does not guarantee stability. Furthermore, instability need not be associated with oscillatory transient response (consider an inverted pendulum merely tipping over from the vertical; oscillation is not guaranteed). Conflating oscillatory transient behavior with positive feedback is a dangerous error. Both negative and positive feedback (and systems with no feedback -- as in a mass on a spring) can exhibit oscillatory, damped, undamped or purely exponential responses (both growth and decay). Additional information is needed to deduce the nature of the system; an output behavior by itself is not sufficient.

If you're going to mount a serious defense of ideas that depend fundamentally on system dynamical behavior, you're going to have to arm yourself much better.

"Get thee to a library."

Lags in the system changes negative feedback to positive feedback which makes a system oscillate.

Systems that are designed to control a variable rather than oscillate have negative feedback. That is a fact.

Perhaps it would help if you or anyone else could explain why the climate would not oscillate if the feedback was positive which amplifies the initial forcing, it might help this discussion. As I said, that does not seem physically possible to me. The researchers in this field who analyzed the data to confirm the feedback is negative made the same statement. That is not an ATM statement.

The researchers in this field specifically noted that large step inputs resulted in infinite model response which is physically not correct. As you noted real physical systems will saturate due to non-linearity in the physical system which is not included in the general circulation models. Obviously infinite response indicates there is a fundamental problem with the GCM.

I do not understand why or how people are defending an assumed positive feedback in the GCM. Lindzen and Choi's finding if correct indicates that feedback is negative not positive.

Do you agree with Lindzen and Choi's finding? If not why not? Same question to Torsten.

As I noted it is a good thing not a bad thing if Lindzen and Choi's finding is correct. If they are correct there will not be dangerous warming due to a doubling of CO2.

Tensor
2011-Aug-24, 10:38 PM
Tensor,

Stop stating this is my ATM theory.

I would like you to show where I stated it was your theory.


I assume you are doing that to bolster a non existing counter scientific argument.

No, what I have done, is to ask you to provide support for specific claims you have made in this thread, which did not involve the original paper. You have yet to answer those. Please see post #26 for questions that are still open.


I provided a link to a paper written by a specialist in this field that analyzes satellite data that indicates the tropical response to a change in forcing is negative. (Clouds in the tropical region increase which results in increased short wave radiation reflected into space). Negative feedback resists forcing changes. Positive feedback amplifies forcing changes. Lindzen and Choi provide further analysis that indicates past analysis methods were flawed and would have erroneously indicated positive feedback. I acknowledge that I am not a specialist in this field. I read Lindzen and Choi's paper and it seems convincing to me, I believe I understand the implications if their conclusion is correct.

You also stated specifically that warming is on a Hiatus, along with other claims, see post #26 for the questions you still have open.


Yes, if Lindzen and Choi are correct the planet will likely significantly cool. Has it yet. No. I agree it has not significantly cooled yet. We are in agreement concerning that statement.

Again, you are moving the goalposts by changing your claim. Your original claim in post #9 and #14 were "an abatement of warming" or "a lack of warming". Now, it's not significantly cooled yet? See post #26 for other open questions.


Did I say we need to wait for more data to definitively know which hypothesis is correct?

Yes, you did. But you also made other statements, and I would ask that you answer the questions I've asked of you, concerning those statements. See post #26 for open questions.

As I noted sometimes it is not clear which hypothesis is correct or incorrect in advance of the new data. In the case of the problem I believe we will find out which hypothesis is or is not correct.

Even if it isn't clear, statements outside the paper still have to be defended. See post #26 for open questions.

William
2011-Aug-24, 10:48 PM
I'll add a further note: whether you created the theory or someone else did, you are presenting it on BAUT and therefore it is your complete responsibility to defend it. And as long as we keep this thread in ATM, it is our determination that it an ATM theory and you are wholely responsible for all the obligations of defending it.

If you do not wish to follow these obligations, state so immediately, and this thread will be closed.

I will defend Lindzen and Choi's analysis and finding which is: The planet's response to a change in forcing is negative (clouds in the tropical region increase to resist warming) rather than positive (planet amplifies warming).

This thread is not to discuss CO2's affects on plants.

Lindzen and Choi are specialists in this field. What I am defending is not William's theory. It is not clear why Lindzen and Choi's finding is ATM and why people are so certain the planet's response to a change in forcing is negative.

I am writing in this section as I was charged with an infraction for stating the conclusion of Lindzen and Choi's paper in the science section. This is therefore the only section where I can discuss Lindzen and Choi's paper.

William
2011-Aug-24, 11:02 PM
Tensor,

Ok let's walk before we try to run. ( I am trying to find out what we agree on and what we disagree on and why.) It is suggested the discussion concerning recent planetary temperature is a distraction. (It appears one is not able to determine why current temperature changes are or are not proof for negative or positive feedback. It is not clear what is the specific forcing function for observed recent temperature fluctuations. See Lindzen and Choi's paper for the reason.)

Lindzen and Choi presented a paper (see first comment this thread) that shows planetary clouds increase in the tropical regions reflecting more radiation into space which resists planetary warming. (negative feedback)

http://www.bautforum.com/showthread.php/119838-On-the-Observational-Determination-of-Climate-Sensitivity-and-Its-Implications-Paper?p=1926397#post1926397

Tensor,

Discussing recent temperature changes appears to not be converging on a conclusion. Let's defer until we have discussed Lindzen and Choi's paper.

http://www.bautforum.com/showthread.php/119838-On-the-Observational-Determination-of-Climate-Sensitivity-and-Its-Implications-Paper?p=1927626#post1927626


Do you support that the finding of that paper? If not why not? (I am inviting questions.)

The logical next question is if Lindzen and Choi finding is correct what would we logically expect to occur or to observe in the future?

Geo Kaplan
2011-Aug-25, 04:13 AM
Lags in the system changes negative feedback to positive feedback which makes a system oscillate.

Again, no. It would take us too far afield for me to educate you on your manifold errors, but consider a first-order system. No amount of feedback -- of any sign -- can make such a system oscillate, for oscillation requires at least a second-order system.

"Get thee to a library." As I said before, you are too unschooled in this subject to be making the assertions you are making.


Systems that are designed to control a variable rather than oscillate have negative feedback. That is a fact.

No. It is not a "fact", it is an assertion by someone who is unjustifiably confident. Again, this is not the place to provide a comprehensive education on the behavior of systems, but suffice it to say that history proves you wrong. Look up "regenerative feedback" (positive feedback), which was invented by Edwin Howard Armstrong before WWI. He used this to increase the amplification factor of circuits built with the primitive vacuum tubes of the time. Oscillation was not a necessary consequence.


Perhaps it would help if you or anyone else could explain why the climate would not oscillate if the feedback was positive which amplifies the initial forcing, it might help this discussion. As I said, that does not seem physically possible to me. The researchers in this field who analyzed the data to confirm the feedback is negative made the same statement. That is not an ATM statement.

OF COURSE it's ATM, because it's wrong. I provided a simple example above -- a first-order system cannot oscillate, no matter what the feedback sign.

Simply stop making claims about the behavior of feedback systems, because it is painfully obvious that you have no idea what you're talking about. Take your own advice and open up any good book on feedback systems. Do more than just open it up, in fact. Study it, for it is clear that you have looked at this topic in only the most superficial ways.

Tensor
2011-Aug-25, 04:53 AM
Tensor,

Ok let's walk before

snip...

or to observe in the future?

Let's make it easy. You go to post #26 and either answer the questions or retract your claims. I included your claims prior to my questions, so there should be no problem figuring out the references for my questions. I'm quite puzzled on why you continue to refuse to answer the questions or continue to change your claims. This is the fourth post and fourth day awaiting answers. If you didn't want your statements challenged, why did you make them? Let's settle your claims THAT ARE ALREADY OUT THERE. Once we take care of those, then we can start over.

William
2011-Aug-26, 03:29 AM
Again, no. It would take us too far afield for me to educate you on your manifold errors, but consider a first-order system. No amount of feedback -- of any sign -- can make such a system oscillate, for oscillation requires at least a second-order system.

"Get thee to a library." As I said before, you are too unschooled in this subject to be making the assertions you are making.



No. It is not a "fact", it is an assertion by someone who is unjustifiably confident. Again, this is not the place to provide a comprehensive education on the behavior of systems, but suffice it to say that history proves you wrong. Look up "regenerative feedback" (positive feedback), which was invented by Edwin Howard Armstrong before WWI. He used this to increase the amplification factor of circuits built with the primitive vacuum tubes of the time. Oscillation was not a necessary consequence.



OF COURSE it's ATM, because it's wrong. I provided a simple example above -- a first-order system cannot oscillate, no matter what the feedback sign.

Simply stop making claims about the behavior of feedback systems, because it is painfully obvious that you have no idea what you're talking about. Take your own advice and open up any good book on feedback systems. Do more than just open it up, in fact. Study it, for it is clear that you have looked at this topic in only the most superficial ways.

Geo Kapaln,

Perhaps if you stopped your tirade and thought about this specific problem. Your sarcastic remark did not address the case of oscillator response to a step input. The standard method of tuning a control system is to create a stepped bump and to measure the period of oscillation of the response. It appears you have no experience with real physical control systems. I do. I do not however want to go off on some tangent that has nothing to do with the subject of this thread.

I have no idea why you are writing your comment. I repeat what does it have to do with this subject?

The logical question that is connected to the subject of this thread is:

Is there any observed difference in the climate system if the feedback is negative vs positive? Are you stating a system with positive feedback has the same characteristics as a system with positive feedback? Is that what you are stating?

As I noted the researchers who found the response of the climate system is negative feedback (planetary clouds increase or decrease in the tropical region to resist a forcing change) as opposed to positive (climate system amplifies forcing changes) noted the general circulation model response for some of the models reached infinity which is physically not possible. The model response would not reach infinite if the feedback is negative. A system that has positive feedback is unstable as in the case of the climate system it will amplify the initial cooling or warming. As I noted the researchers in this field specifically state exactly what I have said.

In the case of the climate system as there are multiple changing inputs positive feedback will amplify the multiple changing inputs which will make the system oscillate in a very complicated manner. (i.e. Not in a simple harmonic pattern.)

Please note insults and advice for me to check books is not a scientific argument. A scientific argument is an attempt to solve a scientific problem.

William
2011-Aug-26, 03:51 AM
Let's make it easy. You go to post #26 and either answer the questions or retract your claims. I included your claims prior to my questions, so there should be no problem figuring out the references for my questions. I'm quite puzzled on why you continue to refuse to answer the questions or continue to change your claims. This is the fourth post and fourth day awaiting answers. If you didn't want your statements challenged, why did you make them? Let's settle your claims THAT ARE ALREADY OUT THERE. Once we take care of those, then we can start over.

Ok Tensor, I will succumb to your continual threats.

I am trying to discuss Lindzen and Choi's paper. I honestly do not understand the point of your comments. Perhaps if you asked a simple question that is a question or if you made statements that compared one hypothesis to another.

I will retract whatever you are alleging that I said concerning the hiatus in warming which is noted in two papers. (the two papers have two completely incomparable explanations for the hiatus in warming.)

The papers that noted that there is a hiatus in warming appear to be a distraction. I agree the papers that noted there is a hiatus in warming cannot be used to support the assertion that the planet's response to an increase in forcing is negative (planetary clouds increase or decrease in the tropical region to resist the forcing change) as opposed to positive (planet amplifies forcing changes).

I repeat, I agree the papers that note there has been a hiatus in warming cannot be used to support the assertion that planet's response to a change in forcing is negative.

I do not however remove my support for the finding of Lindzen and Choi that the planet's response to a change in forcing is negative. I will defend Lindzen and Choi's paper.

I must apologize that I will be slow to response as I am going mountain climbing and will be on the mountain for a few days. If all goes well I will be home very late Sunday or sometime on Monday.

captain swoop
2011-Aug-26, 09:45 AM
William
tensor is not making threats, he is asking you direct questions about your claims.
He has listed your claims and listed his questions.
Either answer the questions as listed by Tensor or withdraw your claims. 'I don't know' is a valid answer

Trakar
2011-Aug-27, 04:32 PM
Trakar,

I provided a link to a paper that is stored at a blog. The link is to a paper not to a blog. I fail to see the logic or reason of your comment.

The paper acknowledges a fact. The warming has stopped. There are actually two papers which attempt to explain the hiatus in warming.


My reasoning, is that by using the blog site as a link instead of the numerous academic sites from which copies of the paper might be obtained you reveal the political, instead of scientific understanding of the paper. This paper does not indicate a stoppage of warming, merely of an increase in the masking effects. In fact, subsequent to that paper's publication we have seen the warming reassert itself with 2010 tying the record for the warmest year in the instrumental record.



Where have you been. As time goes by and there is no warming an explanation is required.


though irrelevent to the Lindzen Choi paper, your assertion of "no warming" is mistaken and without support.



The second paper notes satellite data shows short wave radiation reflected into space in the tropics increased during the period when there was a lack of warming. That finding is in agreement with Lindzen and Choi's paper. The disagreement is on cause.

Lindzen's paper doesn't deal with any area outside of the tropics, uses a very carefully cherry-picked period when natural variations of weather and circumstance induced a partial masking of the predominant positive feedbacks of CO2 climate forcing. As with his previous papers, Lindzen's research is heavily dependent upon a carefully selected period.

We see in Lindzen's paper:
"...There were four major criticisms to Lindzen and Choi (2009): (i) incorrect computation of climate sensitivity, (ii) statistical insignificance of the results, (iii) misinterpretation of air-sea interaction in the Tropics, (iv) misuse of uncoupled atmospheric models..."

When, however, we actually look at the critiques of Lindzen Choi (2009) in such works as Trenberth et al 2010 (http://www.atmosp.physics.utoronto.ca/~jclub/journalclub_files/trenberth2010.pdf), Lin et al 2010 (http://www.atmos-chem-phys.net/10/1923/2010/acp-10-1923-2010.pdf), Murphey 2010 (http://www.agu.org/pubs/crossref/2010/2010GL042911.shtml), and even the less formal considerations of fellow contrarian Roy Spencer (http://www.drroyspencer.com/2009/11/some-comments-on-the-lindzen-and-choi-2009-feedback-study/), we see a much longer list of fundemental problems.

The point being, if all that is known about the subject is what is presented in this single paper, then it is understandable that an intelligent person might be misled into accepting the author's statements and assessments without question. As, however, this paper and subject matter do not exist in a vaccuum of their own generation, but instead within a previously established foundation of presentation and refutation/rebuttal, we need to consider and analyze information beyond that presented by the authors in order to properly assess whether they are actually presenting valid data, addressments, and proposals derived from reasoned and reasonable methodologies and treatments, or they are not. Don't you agree?

Geo Kaplan
2011-Aug-27, 04:45 PM
Geo Kapaln,

Perhaps if you stopped your tirade and thought about this specific problem. Your sarcastic remark did not address the case of oscillator response to a step input. The standard method of tuning a control system is to create a stepped bump and to measure the period of oscillation of the response. It appears you have no experience with real physical control systems. I do. I do not however want to go off on some tangent that has nothing to do with the subject of this thread.

I note for the record that you have not addressed the specific examples I cited. Instead you merely continue unsupported assertions. It is painfully obvious that you have no experience designing control systems. You continue to assert that oscillations are a necessary form of response. Look up "first order response" in any good control textbook. These cannot oscillate. And btw no practictioner of the art calls them "stepped bumps". They are merely "steps." Your lack of knowledge is self-evident in your linguistic slip.

Finally, if an oscillatory response is noted, the period of the oscillation is not how one tunes a control system. We note it, to be sure, but things like overshoot magnitude and settling speed are the parameters of greatest interest. The period of oscillation within that envelope is of secondary significance. You speak as someone who has either never designed real control systems, or simply gotten lucky from a few simple cases and have over-generalized from your limited experience.

These may seem like secondary issues, but in fact, they get to the core. You are basing your support of the referenced paper on their insights regarding system behavior. But as you clearly possess only the most superficial knowledge of this topic, your background is obviously insufficient for you to make the strong assertions you are making.

Trakar
2011-Aug-27, 05:43 PM
Trakar,
...Please do not accuse me of ATM because of your lack of understanding of an issue. It seems to me that you are trying to use the term ATM and writing in capitals as a method of argument. I presented the papers because there are interesting scientifically...

Your understandings/beliefs, are Against The Mainstream (ATM - with proper and appropriate acronym capitalization) science understandings in this area.



I have no problem discussing Lindzen and Choi's paper however I am not a specialist in that area.


Without considerable specialized knowledge and in-depth understanding, it would be extremely difficult for you to properly understand, yet alone defend Lindzen's paper.
Are you sure that you are up to your self-appointed task of defending and addressing the issues regarding this paper?



I noted I read the paper a couple of times. I provided a link to two papers which both acknowledge that there has been hiatus in warming.


Actually, the first paper you proffered as support for this conclusion ("Reconciling anthropogenic climate change with observed temperature 1998–2008" - http://people.bu.edu/mann1123/Pubs_files/Global_Temp_Paper.pdf) does not support that there has been any cessation in the causations of warming.

IOW, though the anthropogenic CO2 forcings continued to increase, these increases were temporarily and partially ameliorated by the anthropogenic forcings due to SO2. It is the short-term net effect of forcings and variation that result in weather and short-term weather trends, it is the cumulative long-term effects of forcings and variation that result in climate.

If we look at the second paper you proffered as support ("Major influence of tropical volcanic eruptions on the stratospheric aerosol layer during the last decade" - http://www.agu.org/pubs/crossref/2011/2011GL047563.shtml), it doesn't seem to discuss or mention any cessation of causation or even warming itself. Rather it focusses on volcanic contributions to the equtorial SO2 aerosol load in the troposphere. While interesting, it neither supports your contention of a cessation of warming, nor does it correlate with any aspect of Lindzen's paper so I see no relevence to it in regards to this thread.

William
2011-Aug-29, 01:34 PM
Tensor,

I did not state
You made specific claims that you said have to be in effect for the Choi paper to be valid for your claimed purpose. For your claims to have any merit, there has to be cooling.

You are confusing your own statements that are not logically correct with what I wrote in this forum. You are confusing how planetary temperatures will change in the future (the planet will likely cool) if Lindzen and Choi's conclusion is correct and what has happened over the last 15 years.

Lindzen and Choi analyzed the satellite data from two different satellites and found that the planet's response to a change in forcing is negative. Planetary clouds increase in the tropical region to resist the forcing change rather than amplify it.

Logically, it does not follow that the planet must have cooled in the last five years for Lindzen and Choi's analysis to be correct. My claim is the Lindzen and Choi analysis and conclusion is correct.

If Lindzen and Choi's analysis and conclusion is correct there will not be extreme AGW warming due to the increase in atmospheric CO2 as planetary clouds in the tropical region will increase to resist warming rather than amplify the CO2 warming. The IPCC 3.5C predicted warming is predicated on the assumption that the tropical region will amplify the CO2 warming. Lindzen and Choi calculate based on their finding concerning the planetary clouds in the tropical region increase to resist warming that a doubling of atmospheric CO2 will result in 0.7C warming.



I did. I read it. I also pointed out a problem with it and asked you specific questions about that paper that you say supports your claims. How about you answer the specific questions I asked?


NO, it's not. You are moving the goalposts. You made specific claims that you said have to be in effect for the Choi paper to be valid for your claimed purpose. For your claims to have any merit, there has to be cooling. You don't have cooling, if yearly variation is taken out. I provided specific papers and graphs, along with explanations that refute your claims. You have not shown my refutations to be wrong (you haven't even bother to answer the questions I posed to you) So the Choi paper is is not valid for the purpose you are claiming for it. You made the claims in post #9. I asked you to support those claims in post #10. And this brings us to post #14.

So let's look at post #14. You presented two papers in Post #14. Neither of the papers mention the Holocene. As a matter of fact, you do not mention the holocene in any of your posts, except to note the age of tree stumps found from retreating glaciers, in post #16.

So, you did not say current compared to the past over a longer period. You just said a hiatus in warming. Then, when asked to provide support for that, you present a paper that details the temperature for the last ten years, but does not indicate if any of the years compared were anomalously high or low. And then don't even present a second paper, just a link to the abstract.


Tensor, As I stated above, anomalously high or low temperatures for a couple of years does not prove or disprove the conclusions of Lindzen and Choi's paper that planetary cloud cover increases in the tropical region to resist warming rather than amplifying it. The concern is the amount of planetary warming that will result from a doubling of atmospheric CO2. Lindzen and Choi's calculate that warming due to a doubling of atmospheric CO2 will be 0.7C as compared to the IPCC calculated 3.5C as planetary clouds in the tropical region will increase to resist the CO2 warming rather than amplify the warming which is what the IPCC currently assumes is the case.


Tensor, Temperatures that are anomalous high for a couple of years does not prove the tropical region amplifies warming. Lindzen and Choi's finding is the tropical region resists forcing changes by an increase of cloud cover.

Since you haven't provided any support for any of your previous statements nor this statement. Yes, I do disagree with it.


Tensor, I provided a link to Lindzen and Choi's paper, first comment this thread. Lindzen and Choi analyzed data from two different, independent satellites to determine the planet's total feedback response to a change in forcing is negative as opposed to IPCC assumed positive feedback. Did you read Lindzen and Choi's paper? What do you disagree about Lindzen and Choi's paper. That is the subject of this thread. You appear to be trying to avoid discussion of Lindzen and Choi's paper diverting discussion to how has the planetary temperature changed in the last 15 year.

You appear to not understand the implication of Lindzen and Choi's paper.

Now, shall we go through the claims and questions in post #14, which you have seemingly ignored:


1. What observations? All I get from the link for the second paper is the abstract. No conclusions, no in depth discussion, just the abstract. Where exactly in that abstract does it talk about the observations of the second paper?

2. Cooling in the Southern Hemisphere? I suggest you look at Fawcett and Jones (http://www.aussmc.org/documents/waiting-for-global-cooling.pdf) Not to mention this graph (http://data.giss.nasa.gov/gistemp/graphs/Fig.A3.gif) . Where in that graph indicates that the Souther Hemisphere has been cooling? Or perhaps you can refute Hansen et al 2010: Global surface temperature change (http://magician.ucsd.edu/~ltauxe/PmagSeminar/miscellaneous/hanson10.pdf)


3. Yeah, you've been saying this, but as you can see in the Fawcett and Jones paper, the Hansen paper, and the graph, there is no "observation" as you claimed. What there was, was a El Nino in 1998. A very strong one. This led to an extremely high mean temperature for the year.

If you compare that one year anomaly with the temperature in 2008 (a year with a strong La Nina) 2008 was a bit cooler than that 1998 anomaly. Not by much, and if you are only comparing the mean temperature for 1998 with 2008, yes it appears that there could be a slight cooling. But, that ignores all the data around 2008. That 1998 was from .3C warmer than 1997 or 1999, you realize what an anomaly 1998 was.

On top of that, 2008 was .2 C cooler than 2007 and 2009, yet it was almost as warm as 1998. 2005, 2006, 2007, 2009 and 2010 were all warmer than 1998 and the five year mean in 2010 was .3 C warmer than 1998. Where in those two papers or in that graph is there a lack of warming?

4. No there isn't. There are some local variations, but overall, it's still rising. From the Hansen paper.

"We suggest use of 12-month (and n×12) running mean temperature to fully remove the annual cycle and improve information content in temperature graphs. We conclude that global temperature continued to rise rapidly in the past decade, despite large year-to-year fluctuations associated with the El Niño-La Niña cycle of tropical ocean temperature. Record high global temperature during the period with instrumental data was reached in 2010."


Tensor,
Two published papers indicate there has been hiatus in warming. A paper refuting Hansen analysis and conclusion has been written and submitted.

As I noted in the future there will likely be planetary cooling which will resolve this issue for the public.

Exactly what in that paragraph would lead you to believe that warming had stopped since 1998? Do you have any data, supported by observations, that support this? Something like that graph I linked to, or something along the line of that Hansen paper would be handy. And, if there is cooling, why was 2010 the hottest year (along with the four of the previous five years) since instrumentation?


Tensor,
As I noted the period of planetary temperature measurement by instrumentation is roughly 150 years. The planet was been warming for the last 150 years. Why? Planetary temperature has increased and decreased during this interglacial period. Why? (i.e. Past planetary temperature changes were not due to CO2. The extreme AGW hypothesis assumes 100% of the late 20th century warming was due to CO2. Planetary temperature in the late 20th century is not anomalous hot compared to planetary temperature for the entire Holocene interglacial period.


5. On another note, Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?



Kaufmann et al had two conclusions: 1) That there was a hiatus in warming. 2) The second was a hypothesis as to what is causing the hiatus in warming.

The planetary temperature data does support the Kaufmann et al's observation that there has been a hiatus in warming. Satellite data however indicates the hiatus in warming is caused by increased short wave radiation reflected from the tropical regions is working to resist any warming.

captain swoop
2011-Aug-29, 04:59 PM
I don't see answers to Tensors listed points.

William
2011-Aug-30, 12:24 AM
Hi Tensor,

The following is in response to your question.

The first paper acknowledges there is an unexplained lack of warming which requires an explanation. The proposed SO2 from Chinese coal burning does not however explain the observations as noted by the second paper. (The problem is there is warming in the Northern Hemisphere and cooling in the Southern Hemisphere. As the SO2 is produced in the Northern Hemisphere and there is little exchange of northern and southern hemisphere aerosol particles the Chinese SO2 emission cannot explain the observation.

One issue with the analysis to explain the lack of warming is it assumes the feedback is positive rather than negative.

The point is there is an acknowledge lack of warming which as I said leaves the door open for Lindzen and Choi's conclusion that the planet's feedback response to a change in forcing is negative (clouds in the tropical region increase in reflecting more short wave radiation into space which resists the forcing change) rather than positive (increased water vapor in the tropical region results in amplification of the CO2 forcing.

I do not understand Tensor's "questions".

He stated my comment number 14# does not reference the Holocene. Yes, it does not.

I did not say it referenced the Holocene. What is his point?

What are his "questions"?

I would suggest he re-ask a couple of questions. I will gladly answer his questions.

Geo Kaplan
2011-Aug-30, 01:47 AM
I do not understand Tensor's "questions". {snip}

What are his "questions"?

I would suggest he re-ask a couple of questions. I will gladly answer his questions.

Why not just start by reading his very clear questions that you yourself quote in post #49?

William
2011-Aug-30, 03:04 AM
Why not just start by reading his very clear questions that you yourself quote in post #49?

In reply to Geo Kaplan.

Although the subject of this thread is Lindzen and Choi's finding that planetary clouds in the tropical region increase to resist warming which works to reduce the warming due to increases in atmospheric CO2 rather than amplify the CO2 greenhouse affect, we can if you wish start discussing the recent hiatus in planetary warming.

I agree, that if Lindzen and Choi's finding is correct there will continue to be a hiatus in warming and there will likely in the future be cooling.

Is there any observational evidence to support that statement?

This is a link to the HadCRUT3 data. It does appear there has been a hiatus in global warming and it does appear there has been cooling in the Southern Hemisphere.

http://www.cru.uea.ac.uk/cru/data/temperature/

http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf

The GISS temperature data is manipulated. It does not agree with the HadCRUT3 data (HadCRUT3 has 1998 as the warmest year which does not agree with GISS). Hansen's group is response for the GISS temperature manipulation. As I am not a specialist in temperature data manipulation I cannot say which data set is correct.

Other specialists in planetary temperature measure have noted there has been a hiatus in global warming and from 2003 to 2008 there is measured cooling of the ocean.

http://www.cru.uea.ac.uk/cru/data/temperature/

Geo or Tensor when you look at this graph is there a hiatus in global warming? Does it appear the Southern Hemisphere is cooling?

If Lindzen and Choi are correct there will continue to be a hiatus in global warming and the planet will likely cool.

http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf


http://wattsupwiththat.files.wordpress.com/2011/07/pnas-201102467.pdf

Data for global surface temperature indicate little warming between 1998 and 2008 (1). Furthermore, global surface temperature declines 0.2 °C between 2005 and 2008. Although temperature increases in 2009 and 2010, the lack of a clear increase in global surface temperature between 1998 and 2008 (1), combined with rising concentrations of atmospheric CO2 and other greenhouse gases, prompts some popular commentators (2, 3) to doubt the existing understanding of the relationship among radiative forcing, internal variability, and global surface temperature. This seeming disconnect may be one reason why the public is increasingly sceptical about anthropogenic climate change (4).

Recent analyses address this source of scepticism by focusing on internal variability or expanding the list of forcings. Model simulations are used to suggest that internal variability can generate extended periods of stable temperature similar to 1999–2008 (5). Alternatively, expanding the list of forcings to include recent changes in stratospheric water vapor (6) may account for the recent lack of warming. But neither approach evaluates whether the current understanding of the relationship among radiative forcing, internal variability, and global surface temperature can account for the timing and magnitude of the 1999–2008 hiatus in warming.

http://www.pas.rochester.edu/~douglass/papers/KD_InPress_final.pdf

Recent energy balance of Earth

Recently Lyman et al. [1] have estimated a robust global warming trend of 0.63 ± 0.28 W/m2 for Earth during 1993–2008, calculated from ocean heat content anomaly (OHC) data. This value is not representative of the recent (2003–2008) warming/cooling rate because of a “flattening” that occurred around 2001–2002. Using only 2003-2008 data, we find cooling, not warming. This result does not support the existence of a large frequently-cited positive computed radiative imbalance (see, for example, Trenberth and Fasullo [2])

http://magician.ucsd.edu/~ltauxe/PmagSeminar/miscellaneous/hanson10.pdf

[76] The likelihood of a record global temperature in the GISS analysis for 2010 raises the question about differences among the several global surface temperature analyses. For example, GISS and NCDC have 2005 as the warmest year in their analyses, while HadCRUT has 1998 as the warmest year. Here we investigate differences arising from two factors that are likely to be important: (1) the way that temperature anomalies are extrapolated, or not extrapolated, into regions without observing stations and (2) the ocean data sets that are employed.

Swift
2011-Aug-30, 01:50 PM
1. What observations? All I get from the link for the second paper is the abstract. No conclusions, no in depth discussion, just the abstract. Where exactly in that abstract does it talk about the observations of the second paper?

2. Cooling in the Southern Hemisphere? I suggest you look at Fawcett and Jones (http://www.aussmc.org/documents/waiting-for-global-cooling.pdf) Not to mention this graph (http://data.giss.nasa.gov/gistemp/graphs/Fig.A3.gif) . Where in that graph indicates that the Souther Hemisphere has been cooling? Or perhaps you can refute Hansen et al 2010: Global surface temperature change (http://magician.ucsd.edu/~ltauxe/PmagSeminar/miscellaneous/hanson10.pdf)

3. Yeah, you've been saying this, but as you can see in the Fawcett and Jones paper, the Hansen paper, and the graph, there is no "observation" as you claimed. What there was, was a El Nino in 1998. A very strong one. This led to an extremely high mean temperature for the year.

If you compare that one year anomaly with the temperature in 2008 (a year with a strong La Nina) 2008 was a bit cooler than that 1998 anomaly. Not by much, and if you are only comparing the mean temperature for 1998 with 2008, yes it appears that there could be a slight cooling. But, that ignores all the data around 2008. That 1998 was from .3C warmer than 1997 or 1999, you realize what an anomaly 1998 was.

On top of that, 2008 was .2 C cooler than 2007 and 2009, yet it was almost as warm as 1998. 2005, 2006, 2007, 2009 and 2010 were all warmer than 1998 and the five year mean in 2010 was .3 C warmer than 1998. Where in those two papers or in that graph is there a lack of warming?

4. No there isn't. There are some local variations, but overall, it's still rising. From the Hansen paper.

"We suggest use of 12-month (and n×12) running mean temperature to fully remove the annual cycle and improve information content in temperature graphs. We conclude that global temperature continued to rise rapidly in the past decade, despite large year-to-year fluctuations associated with the El Niño-La Niña cycle of tropical ocean temperature. Record high global temperature during the period with instrumental data was reached in 2010."

Exactly what in that paragraph would lead you to believe that warming had stopped since 1998? Do you have any data, supported by observations, that support this? Something like that graph I linked to, or something along the line of that Hansen paper would be handy. And, if there is cooling, why was 2010 the hottest year (along with the four of the previous five years) since instrumentation?


5. On another note, Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?William,

You have been asked very specific questions. Instead of addressing them directly, you keep expounding on your original ideas. You will specifically address these and all other direct questions put to you or you will be infracted.

William
2011-Aug-30, 07:11 PM
William,

You have been asked very specific questions. Instead of addressing them directly, you keep expounding on your original ideas. You will specifically address these and all other direct questions put to you or you will be infracted.

Swift,

I can and will answer Tensor's question concerning the second paper on the hiatus in warming.

There is a scientific issue that the GISS temperature data does not agree with the HadCRUT3. I will defend Lindzen and Choi's paper. Who will defend the GISS temperature data set over the HadCRUT3? That is a valid scientific issue not at ATM issue. Please advise.


The conclusions Tensor reached is based on the GISS data. I reached different conclusions as I looked at the HadCRUT3 temperature data. We need a separate thread to discuss which data set is correct. That is complicated subject.



This is a link to the HadCRUT3 data.

http://www.cru.uea.ac.uk/cru/data/temperature/

http://www.cru.uea.ac.uk/cru/data/te...ure/nhshgl.pdf

The GISS temperature data is manipulated. It does not agree with the HadCRUT3 data (HadCRUT3 has 1998 as the warmest year which does not agree with GISS). Hansen's group is response for the GISS temperature manipulation. As I am not a specialist in temperature data manipulation I cannot say which data set is correct.

Other specialists in planetary temperature measure have noted there has been a hiatus in global warming and from 2003 to 2008 there is measured cooling of the ocean.

Tensor
2011-Aug-30, 09:08 PM
Swift,

I can and will answer Tensor's question concerning the second paper on the hiatus in warming.

All I'm looking for is why you think there is a problem with my questions, and any support data you have for your position. When answering them.



There is a scientific issue that the GISS temperature data does not agree with the HadCRUT3.

What specifically is the issue or issues? Even if they are different, do they still show a warming trend, according the data set? And if this is the case, why do you not show how the Fawcett and Jones paper ignores the issue, since they use both (plus a third data set). Or, why not show how the Hansen et al paper is doing a invalid comparison between the two data sets? Or specifically why the conclusions of Hansen et al's paper are invalid.

To be specific. You gave a link to the Hansen et al paper, pulled a quote out of the paper, which seemingly gives you the impression that there are huge differences in the two data sets. Or, in the way they are used. But, you didn't specify anything in the paper, in your statement. When you actually read the paper, examine the analysis, and read the conclusions, you find that Hansen et al find the trends in the two data sets are basically the same. And while one data set may be a bit a different in which years are the hottest (or even the same, see below), they find the trends of the two data sets are, The Earth is Warming, has been warming, and it hasn't cooled since 1998.


I will defend Lindzen and Choi's paper. Who will defend the GISS temperature data set over the HadCRUT3? That is a valid scientific issue not at ATM issue. Please advise.

This is a strawman. The Hansen paper I linked to describes why the two (the GISS and HadCRUT3) may show differences, how to mostly eliminate the differences and why the data, although using different methods, both show warming. Whether or not one data set shows a different year is warmer than another is not pertinent to whether or not the trend, for each data set, is the same. But nowhere, in your recent posts, do you provide us with any kind of critical analysis of this paper.


The conclusions Tensor reached is based on the GISS data.

No I didn't and no it isn't. See Fawcett and Jones. See Hansen et al.


I reached different conclusions as I looked at the HadCRUT3 temperature data. We need a separate thread to discuss which data set is correct.

Which is why I gave you a link to the Fawcett and Jones paper. They do a separate analysis on the HadCRUT3 and GISS data. Both the GISS and HadCRUT3, according the the data listed in that paper, show an increase in warming during the period you claimed has shown cooling. The Hansen et al paper shows why they may get different individual years as hotter, but why the trend for both is the same. Yet you haven't shown anything in that paper to be wrong or, in fact, even shown you have read the paper.

For instance, a likely explanation for discrepancy in identification of the warmest year is the fact that the HadCRUT analysis excludes much of the Arctic, where warming has been especially large in the past decade. With the analyses limited to the same area, the GISS and HadCRUT results are similar. Both GISS and HadCRUT3 show 1998 as the hottest year. This is specifically stated in the paper, yet you didn't even mention this, and in fact, continue to point to the difference in the years the GISS and HadCRUT3 indicate as the hottest years. WHY, if you actually read the paper and know what the Hansen et al paper is doing?

Well, this post give you quite a few more questions. I'll be waiting.

Swift
2011-Aug-31, 02:38 AM
Swift,

I can and will answer Tensor's question concerning the second paper on the hiatus in warming.

There is a scientific issue that the GISS temperature data does not agree with the HadCRUT3. I will defend Lindzen and Choi's paper. Who will defend the GISS temperature data set over the HadCRUT3? That is a valid scientific issue not at ATM issue. Please advise.

Tensor described it well, but I'll make it official. This is your ATM thread. No one needs to defend the mainstream science. You keep wanting to make this a debate between equal positions. That is not the policy on BAUT. Advocation that AGW is not mainstream science is considered ATM. If you do not like that policy, you can find another forum for the debate.

Oh, and as far as "I can and will answer Tensor's question concerning the second paper on the hiatus in warming." - no, you don't get to pick the questions to answer, you will answer all his questions, and those from anyone else.

William
2011-Aug-31, 03:04 AM
Tensor,

If you look at the HadCRUT3 planetary temperature data for the last 150 years what do see? Note they are comparing anomalies so the same data analysis method is used for the entire 150 years.

The HadCRUT3 shows planetary temperatures go up and down during the 150 year period. What is changing to cause the changing temperature? CO2 is not the cause.


http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf

Now on to your questions.


Tensor: What specifically is the issue or issues? Even if they are different, do they still show a warming trend, according the data set? William: NO. And if this is the case, why do you not show how the Fawcett and Jones paper ignores the issue, since they use both (plus a third data set). Or, why not show how the Hansen et al paper is doing a invalid comparison between the two data sets? Or specifically why the conclusions of Hansen et al's paper are invalid. William: Hansen's paper is based on the GISS data that does not agree with the HadCRUT3 both of which do not agree with satellite data. I presented two papers that noted there is a hiatus in warming. Which temperature data is correct?

When I look at the HadCRUT3 temperature data set I see cooling based on their temperature algorithm. Hansen's group's algorithm appears to have removed the cooling.

http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf



[122] 1. The paper provides insight into why the GISS analysis yields 2005 as the warmest calendar year, while the HadCRUT analysis has 1998 as the warmest year. The main factor is our inclusion of estimated temperature change for the Arctic region. We note that SST change cannot be used as a measure of surface air temperature change in regions of sea ice and that surface air temperature change is the quantity of interest both for its practical importance to humans and for comparison with the results that are usually reported in global climate model studies.



All I'm looking for is why you think there is a problem with my questions, and any support data you have for your position. When answering them.

William: The problem with your questions is there are not related to Lindzen and Choi's paper. If Lindzen and Choi's conclusion is correct the planet will cool as a significant portion of the 20th century warming would be do something besides CO2. Has it cooled? That depends on which temperature data set you look at. I am quite confident it will cool more in future and the cooling will be so significant that all data sets will record it.

To be specific. You gave a link to the Hansen et al paper, pulled a quote out of the paper, which seemingly gives you the impression that there are huge differences in the two data sets. Or, in the way they are used. But, you didn't specify anything in the paper, in your statement. When you actually read the paper, examine the analysis, and read the conclusions, you find that Hansen et al find the trends in the two data sets are basically the same. And while one data set may be a bit a different in which years are the hottest (or even the same, see below), they find the trends of the two data sets are, The Earth is Warming, has been warming, and it hasn't cooled since 1998.

When I look at the HadCRUT3 data I see a hiatus in warming with cooling in the Southern Hemisphere. I see 1998 as the warmest year.

http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf

This is a strawman. The Hansen paper I linked to describes why the two (the GISS and HadCRUT3) may show differences, how to mostly eliminate the differences and why the data, although using different methods, both show warming. Whether or not one data set shows a different year is warmer than another is not pertinent to whether or not the trend, for each data set, is the same. But nowhere, in your recent posts, do you provide us with any kind of critical analysis of this paper.

William: The GISS data set does not directly measure the Arctic temperatures. It extrapolates southern measured temperatures to determine arctic temperatures.


[122] 1. The paper provides insight into why the GISS analysis yields 2005 as the warmest calendar year, while the HadCRUT analysis has 1998 as the warmest year. The main factor is our inclusion of estimated temperature change for the Arctic region. We note that SST change cannot be used as a measure of surface air temperature change in regions of sea ice and that surface air temperature change is the quantity of interest both for its practical importance to humans and for comparison with the results that are usually reported in global climate model studies.


No I didn't and no it isn't. See Fawcett and Jones. See Hansen et al.

Which is why I gave you a link to the Fawcett and Jones paper. They do a separate analysis on the HadCRUT3 and GISS data. Both the GISS and HadCRUT3, according the the data listed in that paper, show an increase in warming during the period you claimed has shown cooling. The Hansen et al paper shows why they may get different individual years as hotter, but why the trend for both is the same. Yet you haven't shown anything in that paper to be wrong or, in fact, even shown you have read the paper.

For instance, a likely explanation for discrepancy in identification of the warmest year is the fact that the HadCRUT analysis excludes much of the Arctic, where warming has been especially large in the past decade. With the analyses limited to the same area, the GISS and HadCRUT results are similar. Both GISS and HadCRUT3 show 1998 as the hottest year. This is specifically stated in the paper, yet you didn't even mention this, and in fact, continue to point to the difference in the years the GISS and HadCRUT3 indicate as the hottest years. WHY, if you actually read the paper and know what the Hansen et al paper is doing?

William: The GISS data set does not directly measure the Arctic temperatures. It extrapolates southern measured temperatures to determine arctic temperatures.


[122] 1. The paper provides insight into why the GISS analysis yields 2005 as the warmest calendar year, while the HadCRUT analysis has 1998 as the warmest year. The main factor is our inclusion of estimated temperature change for the Arctic region. We note that SST change cannot be used as a measure of surface air temperature change in regions of sea ice and that surface air temperature change is the quantity of interest both for its practical importance to humans and for comparison with the results that are usually reported in global climate model studies.


Well, this post give you quite a few more questions. I'll be waiting.

captain swoop
2011-Aug-31, 07:58 AM
Is that it a link? addressing one of the questions?
Can you ever answer with anything but al ink to some other site or paper? Make your case and post your answers in this thread, a link can be used to support your answer but shouldn't be offered as an answer itself

Tensor
2011-Aug-31, 07:42 PM
Tensor,

If you look at the HadCRUT3 planetary temperature data for the last 150 years what do see? Note they are comparing anomalies so the same data analysis method is used for the entire 150 years.

And that has what, exactly to do with the fact that, if you use the same areas, on Earth, for comparison, the GISS and the HadCRUT3 show the same rise and also have the same year as the hottest? The fact that there are differences are due to the different areas on the Earth, that are used to determine the surface temperature. To be specific, HadCRUT3 ignores the area that has shown the highest amount of warming over the last 10 years, the arctic.


The HadCRUT3 shows planetary temperatures go up and down during the 150 year period. What is changing to cause the changing temperature? CO2 is not the cause.

Yeah, about that graph. Note that prior to 1980, there were a TOTAL of 14 years where the temperature anomaly was above 0C. Since 1980, 27 of the last 30 years have been above the 0C mark. Not only that, but ONE, count them, ONE, year out of 130 was the anomaly even higher than .2C, prior to 1980. Since then, 19 of the last 30 have been over that .2C mark, with over half of the last 13 years being higher than .5C. What has changed since the huge rise in temperatures? Hmmmm, oh yeah, CO2. Also note, that starting just prior to 1900, which was within 40 years of the start of widespread and heavy use of fossil fuels, the temperature has increased just over a degree C.



http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf

Now on to your questions.

I've gone ahead and put in the quote tags to make this clearer.



Tensor: What specifically is the issue or issues? Even if they are different, do they still show a warming trend, according the data set?William: NO.

That's it, NO? Nothing to explain the no? Nothing to back it up? Just no?



And if this is the case, why do you not show how the Fawcett and Jones paper ignores the issue, since they use both (plus a third data set). Or, why not show how the Hansen et al paper is doing a invalid comparison between the two data sets? Or specifically why the conclusions of Hansen et al's paper are invalid.William: Hansen's paper is based on the GISS data that does not agree with the HadCRUT3 both of which do not agree with satellite data. I presented two papers that noted there is a hiatus in warming. Which temperature data is correct?

And with the statement about those two papers, we're back to post #22 (http://www.bautforum.com/showthread.php/119838-On-the-Observational-Determination-of-Climate-Sensitivity-and-Its-Implications-Paper?p=1927295#post1927295) in this thread. Where I asked questions about those two papers, and never got any answers. I've been waiting for a week and 36 posts. I'll repeat those questions here for you.

Q1 What observations? The second paper you linked to, the one about volcanic eruptions, leads to an abstract only. With no link to the actual paper, without belonging or subscribing to GEOPHYSICAL RESEARCH LETTERS. Which means we can't see any of the calculations, discussions, methods or other things that can be used to evaluate the paper. Nor can we see the actual conclusions of the paper. And, just because it talks about the amount of SO2 entering the atmosphere, it does not show how this affects warming, if at all. So again, what observations of that paper support a hiatus?

2. The first paper, Kaufman et al (which includes Mann) is connected to the Hansen paper as Hansen shows that the HadCRUT3 data does not include the area of the Earth that has displayed the most warming over the last decade, the arctic.

In addition, "...Thus, HadCRUT implicitly assumes that areas without observations have a temperature anomaly equal to the hemispheric mean anomaly. Given the pattern of large temperature anomalies in the fringe Arctic areas with data (Figure 12), this implicit estimate surely under- states the effect of Arctic temperature anomalies."

Hmmmmm, the arctic is warming rapidly, HadCRUT very likely understates the warming near the arctic, and doesn't account for the warming in the arctic. Isn't it obvious why HadCRUT is showing slower increase trend? This was all in the paper you presented as evidence.

Q2 And yet, when I asked you to present a reason why Hansen et al was wrong, your didn't provide an answer.

Q3 Not to mention, I ask the following question specifically: Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?

All three of those questions have been waiting for a week now. Along with those in post #46 Post #26


When I look at the HadCRUT3 temperature data set I see cooling based on their temperature algorithm. Hansen's group's algorithm appears to have removed the cooling.

http://www.cru.uea.ac.uk/cru/data/temperature/nhshgl.pdf

Yeah, not sure why you're linking to the same graph twice. The red area on the right, showing the increase is still there, in the Northern Hemisphere, the Southern Hemisphere, and the Global.

William
2011-Sep-01, 02:32 AM
Tensor,

It appears you have answered your 36 questions. The planet continues to warm according to the Hansen group's GISS manipulated temperatures. The planet appears to be cooling based on the HadCRUT3 temperature data set.

It is interesting that the Argo ocean temperature data indicates the planet is cooling. Oceans cover 70% of the earth's surface. More fraudulent science? Hansen to the rescue?


http://www.pas.rochester.edu/~dougla...ress_final.pdf


Recent energy balance of Earth

Recently Lyman et al. [1] have estimated a robust global warming trend of 0.63 ± 0.28 W/m2 for Earth during 1993–2008, calculated from ocean heat content anomaly (OHC) data. This value is not representative of the recent (2003–2008) warming/cooling rate because of a “flattening” that occurred around 2001–2002. Using only 2003-2008 data, we find cooling, not warming. This result does not support the existence of a large frequently-cited positive computed radiative imbalance (see, for example, Trenberth and Fasullo [2])

It is interesting to note another La Nina is starting to form as opposed the Hansen group predicted a El Nino. (The extreme AGW has actually predicted as a continual series of large El Ninos). I am curious at what point it will obvious to the general public that the planet is cooling.

Is is possible Hansen may lack scientific objectivity? Is he an impartial scientist first or an advocate where the end justifies the means? Hansen is the director of the agency that hires the climate scientists that manipulates the temperatures for the GISS data base and has been arrested three times protesting AGW related issues. Hansen is 70 years old and started his AGW campaign in the 1980s. Hansen is also the lead author of the papers which you are quoting. I watched Hansen being interviewed by David Letterman. I was astonished at his arrogance and self importance. Gavin Schmidt the lead writer on the RealClimate blog is employed by Hansen.

The subject of this ATM is the fourth paper that indicates that clouds in the tropical region increase to resist warming (negative feedback) as opposed to amplifying warming. Lindzen and Choi, the authors of this paper calculate planetary warming due to a doubling of atmospheric CO2 to be 0.7C due cover cover in the tropical region increasing to resist the CO2 warming as opposed to the IPCC predicted warming of 3.5C which requires the atmosphere amplifies the warming.

So far you have not asked a single question concerning the subject of this ATM.

http://www.bautforum.com/showthread.php/119838-On-the-Observational-Determination-of-Climate-Sensitivity-and-Its-Implications-Paper?p=1926397#post1926397



And that has what, exactly to do with the fact that, if you use the same areas, on Earth, for comparison, the GISS and the HadCRUT3 show the same rise and also have the same year as the hottest? The fact that there are differences are due to the different areas on the Earth, that are used to determine the surface temperature. To be specific, HadCRUT3 ignores the area that has shown the highest amount of warming over the last 10 years, the arctic.



Yeah, about that graph. Note that prior to 1980, there were a TOTAL of 14 years where the temperature anomaly was above 0C. Since 1980, 27 of the last 30 years have been above the 0C mark. Not only that, but ONE, count them, ONE, year out of 130 was the anomaly even higher than .2C, prior to 1980. Since then, 19 of the last 30 have been over that .2C mark, with over half of the last 13 years being higher than .5C. What has changed since the huge rise in temperatures? Hmmmm, oh yeah, CO2. Also note, that starting just prior to 1900, which was within 40 years of the start of widespread and heavy use of fossil fuels, the temperature has increased just over a degree C.




I've gone ahead and put in the quote tags to make this clearer.



That's it, NO? Nothing to explain the no? Nothing to back it up? Just no?



And with the statement about those two papers, we're back to post #22 (http://www.bautforum.com/showthread.php/119838-On-the-Observational-Determination-of-Climate-Sensitivity-and-Its-Implications-Paper?p=1927295#post1927295) in this thread. Where I asked questions about those two papers, and never got any answers. I've been waiting for a week and 36 posts. I'll repeat those questions here for you.

Q1 What observations? The second paper you linked to, the one about volcanic eruptions, leads to an abstract only. With no link to the actual paper, without belonging or subscribing to GEOPHYSICAL RESEARCH LETTERS. Which means we can't see any of the calculations, discussions, methods or other things that can be used to evaluate the paper. Nor can we see the actual conclusions of the paper. And, just because it talks about the amount of SO2 entering the atmosphere, it does not show how this affects warming, if at all. So again, what observations of that paper support a hiatus?

2. The first paper, Kaufman et al (which includes Mann) is connected to the Hansen paper as Hansen shows that the HadCRUT3 data does not include the area of the Earth that has displayed the most warming over the last decade, the arctic.

In addition, "...Thus, HadCRUT implicitly assumes that areas without observations have a temperature anomaly equal to the hemispheric mean anomaly. Given the pattern of large temperature anomalies in the fringe Arctic areas with data (Figure 12), this implicit estimate surely under- states the effect of Arctic temperature anomalies."

Hmmmmm, the arctic is warming rapidly, HadCRUT very likely understates the warming near the arctic, and doesn't account for the warming in the arctic. Isn't it obvious why HadCRUT is showing slower increase trend? This was all in the paper you presented as evidence.

Q2 And yet, when I asked you to present a reason why Hansen et al was wrong, your didn't provide an answer.

Q3 Not to mention, I ask the following question specifically: Since you provided that link to Kaufmann et al paper, you agree with their conclusions, right?

All three of those questions have been waiting for a week now. Along with those in post #46 Post #26



Yeah, not sure why you're linking to the same graph twice. The red area on the right, showing the increase is still there, in the Northern Hemisphere, the Southern Hemisphere, and the Global.

Torsten
2011-Sep-01, 03:32 AM
William:

I said in the first line of my first post in this thread that I neither have the time or experience to properly evaluate the paper you are advocating. (Things have also become a little more demanding in my off-line life since my last post.) However, two questions:

1. What is wrong with the explanation of the factors that contribute to the difference in the HadCRUT3 versus GISS records? I want carefully considered elaboration and not some conspiracy drivel that I can read at WUWT when I go slumming. So far, that is all you've provided.

2. I want to know how you came to make your earlier statement that there was no warming prior to 1994. I want to know whether this was a typo, or whether you did what I thought you did (use only the UAH record from 1979 to the end of 1993). You just left it hanging there, and have since gone on about the HadCRUT3 versus GISS difference, but seem to remain willingly oblivious to the reasons for it.

Torsten
2011-Sep-01, 05:09 AM
Cherry picking is so challenging. So many choices!

http://i259.photobucket.com/albums/hh315/TKphotofolder/BAUT/UAH_Variety_through_July_2011.png

Credit: WoodForTrees (http://www.woodfortrees.org/plot/uah/from:1978/to:1998/trend/plot/uah/from:1998/to:2012/trend/plot/uah/plot/uah/from:2002/to:2009/trend/plot/uah/from:1986/to:1994/trend/plot/uah/from:1980/to:1986/trend/plot/uah/from:1999/to:2009/trend/plot/uah/trend)

When exactly is that negative feedback mechanism supposed to counter the rise in temperature?

See that yellow line for the period 1999 through 2008? Isn't it funny how the UAH record, which shows the lowest overall upward trend of the datasets mentioned in this thread, should have that period almost perfectly match the trend for the entire dataset?

captain swoop
2011-Sep-01, 08:00 AM
William
It seems you either won't or can't answer any questions put to you.
Now you accuse Hansen of fraud.

this thread is closed pending Mod discussion and I am giving you an infraction for repeatedly ignoring Mod instructions
Any representations as to why it should remain open can be made by reporting this post