Guest post by Dr. Roger Pielke Senior
Missing The Major Point Of “What Is Climate Sensitivity”
There is a post by Zeke on Blackboard titled Agreeing [See also the post on Climate Etc Agreeing(?)].
Zeke starts the post with the text
“My personal pet peeve in the climate debate is how much time is wasted on arguments that are largely spurious, while more substantive and interesting subjects receive short shrift.”
I agree with this view, but conclude that Zeke is missing a fundamental issue.
Zeke writes
“Climate sensitivity is somewhere between 1.5 C and 4.5 C for a doubling of carbon dioxide, due to feedbacks (primarily water vapor) in the climate system…”
The use of the terminology “climate sensitivity” indicates an importance of the climate system to this temperature range that does not exist. The range of temperatures of “1.5 C and 4.5 C for a doubling of carbon dioxide” refers to a global annual average surface temperature anomaly that is not even directly measurable, and its interpretation is even unclear, as we discussed in the paperPielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, S. Foster, R.T. McNider, and P. Blanken, 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res., 112, D24S08, doi:10.1029/2006JD008229.
This view of a surface temperature anomaly expressed by “climate sensitivity” is grossly misleading the public and policymakers as to what are the actual climate metrics that matter to society and the environment. A global annual average surface temperature anomaly is almost irrelevant for any climatic feature of importance.
Even with respect to the subset of climate effects that is referred to as global warming, the appropriate climate metric is heat changes as measured in Joules (e.g. see). The global annual average surface temperature anomaly is only useful to the extent it correlates with the global annual average climate system heat anomaly [most of which occurs within the upper oceans]. Such heating, if it occurs, is important as it is one component (the “steric component”) of sea level rise and fall.
For other societally and environmentally important climate effects, it is the regional atmospheric and ocean circulations patterns that matter. An accurate use of the terminology “climate sensitivity” would refer to the extent that these circulation patterns are altered due to human and natural climate forcings and feedbacks. As discussed in the excellent post on Judy Curry’s weblog
finding this sensitivity is a daunting challenge.
I have proposed definitions which could be used to advance the discussion of what we “agree on”, in my post
The Terms “Global Warming” And “Climate Change” – What Do They Mean?
As I wrote there
Global Warming is an increase in the heat (in Joules) contained within the climate system. The majority of this accumulation of heat occurs in the upper 700m of the oceans.
Global Cooling is a decrease in the heat (in Joules) contained within the climate system. The majority of this accumulation of heat occurs in the upper 700m of the oceans.
Global warming and cooling occur within each year as shown, for example, in Figure 4 in
Ellis et al. 1978: The annual variation in the global heat balance of the Earth. J. Geophys. Res., 83, 1958-1962.
Multi-decadal global warming or cooling involves a long-term imbalance between the global warming and cooling that occurs each year.
Climate Change involves any alteration in the climate system , which is schematically illustrated in the figure below (from NRC, 2005)
which persists for an (arbitrarily defined) long enough time period.
Shorter term climate change is referred to as climate variability. An example of a climate change is if a growing season 20 year average of 100 days was reduced by 10 days in the following 20 years. Climate change includes changes in the statistics of weather (e.g. extreme events such as droughts, land falling hurricanes, etc), but also include changes in other climate system components (e.g. alterations in the pH of the oceans, changes in the spatial distribution of malaria carrying mosquitos, etc).
The recognition that climate involves much more than global warming and cooling is a very important issue. We can have climate change (as defined in this weblog post) without any long-term global warming or cooling. Such climate change can occur both due to natural and human causes.”
It is within this framework of definitions that Zeke and Judy should solicit feedback in response to their recent posts. I recommend a definition of “climate sensitivity” as
Climate Sensitivity is the response of the statistics of weather (e.g. extreme events such as droughts, land falling hurricanes, etc), and other climate system components (e.g. alterations in the pH of the oceans, changes in the spatial distribution of malaria carrying mosquitos, etc) to a climate forcing (e.g. added CO2, land use change, solar output changes, etc). This more accurate definition of climate sensitivity is what should be discussed rather than the dubious use of a global annual average surface temperature anomaly for this purpose.
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“climate forcing”
Surely a less-wrong term for that is “perturbation”.
Terminology consistent with control systems theory and Engineering.
Carrick,
“based on a correlation length of 500-km … So, either there’s something wrong with the sampling theorem, or there’s something wrong with the statement that the correlation length for a 1-month band-limited signal is 500-km.”
No, there is a third possibility, which is in correct interpretation of data. The correlation is a broad function that accounts for many time scales. The correlation length (peak position) you mention is formed and dominated by SHORT-TERM seasonal variations. AGW people love to point out that summers are warmer than winters. That’s why stations at 500km – 1200km distance “correlate well”. However, we are trying to talk here about century-long CLIMATE trends, and the observational evidence (see GISS stations) shows that the long-term correlation breaks even at 50km distance. Sorry to point this out. Please don’t repeat the mistake made in the article of Hansen and Lebedeff (1987).
BTW, I have made this argument on several occasions. Apparently it was not scientific enough to your AGW taste and was ignored. I feel that this time will be no different.
mpaul says:
February 28, 2011 at 4:35 pm
“Mosh, how about this:”
If I may give my take…
The following numbered statements are your suggestions, the indented statements are my replies.
(1) Its gotten warmer since the last mini ice age
—-As expressed as a global average this is true. Regionally its less clear-cut, locally it varies. But the rise in sea level after ~6000 years of stasis and evidence from borehole data indicate the recent warming is a robust signal.
(2) Dumping large amounts of CO2 and other by-products of fossil fuel combustion into the atmosphere is hazardous to human life and to the common welfare
—-The degree of hazard it represents has more to do with how robust human agricultural systems and societies are to the changes that increasing CO2 will inflict.
You cant change just one thing in a compex interactive system, so raising CO2 will cause other changes. Even if we knew EXACTLY what changes it would cause, whether such changes are hazardous is dependent on societal adaptability.
Only if you regard any and all change as hazardous is it valid to ignore the magnitude or the societal response.
(3) We should be aggressively pursuing alternative sources of cheap clean energy as a national priority
—-Obviously.
(4) Climate science has been corrupted by politics and some prominent climate scientist are willing to falsify results and cherry pick data in order to achieve power, fame and career advancement.
—-Despite the frequency of this claim there is little or no good evidence for its accuracy.
Politics has distorted Climate science for its own ends. Sometimes to raise ‘alarmist’ scenarios and sometimes to eschew it.
(5) Prominent climate scientists have systematically overstated confidence in results and the degree of scientific consensus
—-Overstated confidence is occasional rather than systematic, and the degree of scientific consensus has been understated. The degree of confidence with which the AGW theory is rejected vastly exceeds the obverse, and media ‘balance’ tends to imply its a fifty:fifty split, or perhaps ten-to-one while the reality is over 98-1.
(6) The climate science community is unwilling and unable to enforce a meaningful code of professional conduct.
—-No more or less than every other field of science. Other fields of research have equally patchy, or worse records of unprofessional behavior.
(7) Global mean surface temperature is meaningless and attempts at measuring it are illusory.
—-Global mean surface temperature is a very rough metric of global heat content. Until satellite observations no attempt was made to measure it. It was derived from local measurements taken to measure the local weather. This makes the surface temperature record less than ideal as a source for calculating global mean temperature.
(8) Modeling of the climate with any degree of predictive power (beyond a few weeks) is well beyond the current state of technology
—-Wrong.
You cant predict the weather, but models would predict that January of 2019 in Northern Europe will be colder than August 2019. I would suggest this is a robust result from modeling.
(9) Current estimate of climate sensitivity are unsupported by direct evidence
—-The qualifier ‘direct’ is the problem here. How direct do you consider the evidence from volcanic climate change like Pichon/Pinatubo or glacial cycles?
(10) We have not been able to characterize natural variability in the climate and as such we are unable to determine the significance of the anecdotal warming
—-We CAN characterize natural variability but with varying degrees of accuracy and resolution over different timescales.
The significance of recent warming is that it is certainly exceptional compared to natural variation of the last 500 years. If you expand the timescale the uncertainty increases, there COULD be comparable events a few thousand years ago, but you have to go back to the end of the last ice-age and the Holocene optimum around 8000 years ago to get any good evidence of similar warming. Expand the timescale further and resolution drops way down, but there are credible candidates for natural variability greater than the present warming.
The trouble is that present technological advanced societies are a recent development, within the last few centuries, so multi-millennial periods are of rather less relevance. Agriculturally based society is only ~8000 years old so again deep time variability is of less significance. Our present society is adapted for the stable climate of the last few centuries, and the warming most likely to derive from doubling CO2 will exceed the natural variability seen over the same time period. How significant that is depends on how robust present complex technological society is in the face of variability outside the natural range already experienced.
I’m somewhat new to the general discussion re AGW, so I’m curious as to how this characteristic length of 500km was derived. And I assume it was tested and verified? I am skeptical at first glance. 500km from my home takes me north to about Montreal or south to North Carolina and west almost into Ohio. The idea that temperature measurements at each of these points is sufficient to describe the entire temperature field between them strikes me as…ambitious.
Izen gives the latest alarmist talking points in response to mpaul’s list. Off the top of my head I can see some problems with Izen’s responses:
#1: “…the rise in sea level after ~6000 years of stasis and evidence from borehole data indicate the recent warming is a robust signal.” The sea level has been rising since the end of the last global glaciacion, although the rise has moderated. Look closely and you will see the rise – and the sharper rise since the LIA. [And -1 for using “robust.”☺]
#2: The endlessly repeated prediction was for runaway global warming to begin by now as a result of increasing CO2. That has not happened, so the goal posts were moved to “climate change.” But the only folks who believe the climate doesn’t change are the true believers in CAGW and Mann’s debunked Hokey Stick. The assumption is that change is bad. But there is no evidence of any global harm from more CO2. The only quantifiable result is increased agricultural productivity. [Another -1 for “debunked” again.]
#4: Anyone who seriously believes that climate science has not been corrupted must be living on another planet. The sidebar has books giving detailed evidence of corruption by the ruling clique of climate charlatans.
#5: “The degree of confidence with which the AGW theory is rejected vastly exceeds the obverse, and media ‘balance’ tends to imply its a fifty:fifty split, or perhaps ten-to-one while the reality is over 98-1.”
Hogwash. First, either Izen doesn’t understand the scientific method, or he’s craftily trying to promote at best a hypothesis to a theory. It is not a theory because it cannot make accurate predictions. And he trots out that debunked 98%-of-climate-scientists-believe horse manure. You couldn’t get 98% of a group to agree that the Pope is Catholic. It was a badly worded push-poll; talk about pseudo-science.
#6: The climate science community is corrupted by money. Izen says every other branch of science is equally corrupt, “no more or less.” Shall we begin by discussing mathematics?
#8: “You cant predict the weather, but models would predict that January of 2019 in Northern Europe will be colder than August 2019. I would suggest this is a robust result from modeling.”
Don’t be silly. The difference between January and August is seasonal. You don’t need a model to understand that. [Another -1 for a third “robust.”]
#9: I’ll take Dr Lindzen’s educated estimate of ≈1°CX2CO2 over the agenda driven UN/IPCC. And Lindzen’s estimate is higher than other well known climatologists.
#10 is complete opinion, and it flies in the face of numerous peer reviewed geological studies going back decades. Izen says: “Our present society is adapted for the stable climate of the last few centuries, and the warming most likely to derive from doubling CO2 will exceed the natural variability seen over the same time period. How significant that is depends on how robust present complex technological society is in the face of variability outside the natural range already experienced.”
Complete circular argument: “…warming will most likey…”, followed by the conclusion, which assumes a priori that the supposed changes will be outside natural variability. [Another “robust.” -1. Total: -4. 60%. Fail.]
The blogs of the alarmists who spout this clown college nonsense didn’t make the “Best Science” finals for a good reason. CO2=CAGW has been downgraded from a hypothesis to a conjecture becuase it fails the most basic tests of the scientific method.
I wouldn’t care so much, but I remember Izen pontificating about how he comes here just to have some fun with skeptics. Having fun now, Izen?
DJ Hawkins:
It’s the measured average correlation length. I wouldn’t be surprised if it were an elongated oval (greater correlation east to west than north to south). Certainly that becomes true as you shorten the averaging interval.
But keep in mind that they are anomalizing (subtracting the mean value for that location) before computing the correlation.
mpaul
As I suggested people should start by answering zeke’s questions to the best of their ability. Even if to say they disagree with all of it. It’s impossible to have the debate you want to have without an understanding of where the points of common agreement are:
Like so:
(1) Its gotten warmer since the last mini ice age:
>95% certain
(2) Dumping large amounts of CO2 and other by-products of fossil fuel combustion into the atmosphere is hazardous to human life and to the common welfare
Poorly articulated. Quantify “large” that we we know what we are talking about.
your idea of large may not be my idea of large. Numbers make for clarity
(3) We should be aggressively pursuing alternative sources of cheap clean energy as a national priority
Yes, but define agressively.
(4) Climate science has been corrupted by politics and some prominent climate scientist are willing to falsify results and cherry pick data in order to achieve power, fame and career advancement.
Overgeneralized motive hunting. I would stick to particular cases and then
realize that I cannot know with any certainty what lies in man’s heart. I’ve seen
no evidence of willful falsification of data. I’ve seen questionable methods.
(5) Prominent climate scientists have systematically overstated confidence in results and the degree of scientific consensus
Again, I would stick to the cases I have studied. There appears to be some
overconfidence.
(6) The climate science community is unwilling and unable to enforce a meaningful code of professional conduct.
Not sure about unwilling, unable ? hard to judge without evidence.
(7) Global mean surface temperature is meaningless and attempts at measuring it are illusory.
False. It’s a proxy that has some uses. OHC is obviously better.
(8) Modeling of the climate with any degree of predictive power (beyond a few weeks) is well beyond the current state of technology
False. Ill specified. the term you are looking for is actually “skill” skill is a technical
measure. GCMs have skill. This is typically measured as skill over a naive forecast.
(9) Current estimate of climate sensitivity are unsupported by direct evidence
False. There are multiple lines of evidence supporting the range of estimates.
Direct measurement. Analysis of observational data. Paleo data, and constraints
imposed by phsyical models. For example, The paleo history clearly rules out
some very high estimates and some very low estimates. We will never (in our lifetime)have a
single number for this. It will always be a range.
(10) We have not been able to characterize natural variability in the climate and as such we are unable to determine the significance of the anecdotal warming
Well, that means that the “null” cannot be specified and cannot be falsified and
is not therefore a Null. I’d agree with Peter Webster that natural variablity ( especially coupling of oscilating modes) has not been adequately studied. Part of
the reason Im a lukewarmer.
Al Tek:
Data are data, and it’s possible to compute the spatial correlation length on its own merits. Whatever that number is tells you something about the data. “Interpretation” is something you do in art class.
There is a systematic basis for approaching the data, and you’re avoiding it by trying to focus on rhetoric instead.
Which sites are you talking about? On average, all of the stations at the same latitude follow the same trend, and the trend increases in a systematic fashion with latitude.
See e.g. here. This was obtained without any assumption of spatial correlation. Just an average of stations in 5° latitudinal bands.
You’ve made arguments, but you’ve never followed them up with proof.
The data’s all there for immediate download, and the main studies are all peer reviewed and available outside of pay walls. GISTEMPs algorithm and code is fully publicized for your and anybody else’s review.
If you want to get technical, you have to run the numbers, not just talk. Just like many of us have actually done. You claim some skill at this, looks like it’s your turn to put up or shut up.
Mpaul.
You might want to consider the oddity of these two:
(1) Its gotten warmer since the last mini ice age
(7) Global mean surface temperature is meaningless and attempts at measuring it are illusory.
#######
Lots of people who dont believe in a global temperature index simultaneously believe that “it” was colder in the LIA. Odd, but they do.
Okay, pretend I don’t know anything about anomalizing and constructing the correlation (not a stretch) and tell me how the temperature at Bloomingdale NJ and Montreal QC is a good description of the temperature field that includes the Hudson Valley, Appalachian mountains, and Lake Champlain. And who proved (or made a brilliant argument) that the characteristic length of 500km was appropriate. Use small words so I can follow. Or a link or two; I won’t consider it cheating if you think someone’s already done a bang up explanation elsewhere.
mpaul “(3) We should be aggressively pursuing alternative sources of cheap clean energy as a national priority”
Mosher “Yes, but define aggressively.”
Manhattan Project to build a commercially viable thorium reactor
mpaul “(4) Climate science has been corrupted by politics and some prominent climate scientist are willing to falsify results and cherry pick data in order to achieve power, fame and career advancement.
Mosher: “Overgeneralized motive hunting. I would stick to particular cases and then
realize that I cannot know with any certainty what lies in man’s heart. I’ve seen
no evidence of willful falsification of data. I’ve seen questionable methods.”
“Censored” directory; R**2 testimony
mpaul “(5) Prominent climate scientists have systematically overstated confidence in results and the degree of scientific consensus”
Mosher “Again, I would stick to the cases I have studied. There appears to be some
overconfidence.”
Climate Change Assessments Review of the Processes and Procedures of the IPCC, InterAcademy Council, 30 August 2010: “… authors reported high confidence in some statements for which there is little evidence. Furthermore, by making vague statements that were difficult to refute, authors were able to attach ‘high confidence’ to the statements. The Working Group II Summary for Policymakers contains many such statements that are not supported sufficiently in the literature…”
mpaul: “(8) Modeling of the climate with any degree of predictive power (beyond a few weeks) is well beyond the current state of technology”
Mosher “False. Ill specified. the term you are looking for is actually “skill” skill is a technical measure. GCMs have skill. This is typically measured as skill over a naive forecast.
No. “Skill” is a term used by academics. I’m an applied scientists. I’m using the term predictive power in a precise sense. To quote von Neumann: “If you allow me four free parameters I can build a mathematical model that describes exactly everything that an elephant can do. If you allow me a fifth free parameter, the model I build will forecast that the elephant will fly.”
mpaul “9) Current estimate of climate sensitivity are unsupported by direct evidence”
Mosher “False. There are multiple lines of evidence supporting the range of estimates.”
Name one.
Carrick wrote:
“Data are data … Whatever that number is tells you something about the data. “Interpretation” is something you do in art class.”
Funny. You do realize that if a “number tells you something”, it is an interpretation, do you? But I never attended any “art class” and my English is second hand, so I will take your word on this 🙂
Carrick:
“You’ve made arguments, but you’ve never followed them up with proof.”
Really? How about these data references?
http://wattsupwiththat.com/2010/09/22/arctic-isolated-versus-urban-stations-show-differing-trends/#comment-489483
http://ourchangingclimate.wordpress.com/2010/03/08/is-the-increase-in-global-average-temperature-just-a-random-walk/#comment-1627
http://ourchangingclimate.wordpress.com/2010/03/08/is-the-increase-in-global-average-temperature-just-a-random-walk/#comment-1733
http://noconsensus.wordpress.com/2010/09/02/in-search-of-cooling-trends/#comment-35823
Looks like your turn is long overdue.
Steven Mosher,
“It” refers to current temperatures. That’s not, as you say, ‘odd.’ It is a fact that the LIA was colder than today.
And I’ll respond to one of your comments:
“We have not been able to characterize natural variability in the climate and as such we are unable to determine the significance of the anecdotal warming”
“Well, that means that the ‘null’ cannot be specified and cannot be falsified and
is not therefore a Null.”
Both comments are incorrect. The climate null hypothesis is ‘the statistical hypothesis that states that there are no differences between observed and expected data.’
The ‘expected data’ of the alternative hypothesis is that runaway global warming will exceed the parameters of the past ten millennia [the Holocene]. That is not even close to happening. Far from it.
Falsifying the null is easy: just show that current temperatures exceed the parameters of the last ten thousand years. Clearly, they do not. Thus, the alternative CO2=CAGW hypothesis is falsified.
steven mosher says:
February 28, 2011 at 8:32 pm
“Mpaul.
You might want to consider the oddity of these two:
(1) Its gotten warmer since the last mini ice age
(7) Global mean surface temperature is meaningless and attempts at measuring it are illusory.”
———————————–
There’s little doubt in my mind that the earth has warmed a bit since the last mini ice age. Global mean surface temperature (anomaly) is an index that attempts to quantify the temperature anomaly at the “surface” of the planet yet is so poorly defined as to be meaningless. Think about it this way, what specification would you need to design a a system to measure global mean surface temperature anomaly. Do you think you have such clarity in the term today?
Carrick wrote: “Just an average of stations in 5° latitudinal bands.”
You seem to miss a simple point: if you don’t have sufficient density of sampling, you don’t (and can’t) know what you are missing. Data collected without regard for theoretical requirement for sampling are garbage. The only way to have confidence in a series of spatio-temporal data is to have substantially high sampling density first, then gather convincing evidence that further increases (and decreases) in sampling density don’t change the result significantly, and then back up to smallest reasonable density. Whoever does not understand this simple procedure is practicing garbage science, and all results must be safely discarded and conclusions ignored.
For people who didn’t read it, Willis reposted Hansen’s original peer-reviewed results for correlation vs distance:
figure here.
You can see that 500-km is a pretty conservative number globally.
I agree with Al Tek that it would be interesting to break this up e.g. by season. I also think East-West versus North-South would be interesting (and I plan to run this case when I get a shot).
One thing I would predict (meaning I haven’t tested this personally) is that when you look at stations along the coastline, you get a loss of coherence with the interior… the so called “coastal boundary layer” plays a role. There is roughly 350,000 km of coastline around the world (easy to remember: It’s roughly the distance from the Earth to the Moon), which is means about 3% of the Earth’s surface is affected by the coastal boundary layer.
To give an idea what this means for the global mean temperature reconstructions: for this to affect the accuracy of the global mean temperature trend by 1% would require more than a 30% error in the estimates of the coastline.
Last I check the “admitted error” in the global mean temperature trend is about 10%. So you’d need a 300% error in coastlines for that to be equal in magnitude. That doesn’t strike me as plausible personally.
Now where did I put that packet of Zingers….
I’ll also note that I’ve posted my own analyses, as well as those of others. Al Tek as yet to post a single plot of his own. This comment says all it needs to say.
“This is not about talking a poll and deciding the truth. It’s about seeing what agreement there is and what disagreement.”
This is precisely why no policy makers should be involved in this type of discussion, why the IPCC’s role is overblown and improper, and why all the politics that has surrounded the science development should stop. Until you guys who are scientists can really figure out what is going on (and I believe all of you know a lot less than you think you know – how can a science that has only about 50 years of satisfactory, reliable measurements be convinced it knows everything already?), policy makers are wasting their time. UNless, of course (note the pun there), your agenda is to control and rule the world.
We humans seem to really think with all of our proxies, surface temperature measurements, satellites, etc., that we know something substantial about the climate of the earth, when we aren’t even close. Scientists should not think themselves so wise that they are prepared to make recommendations concerning what, if anything, to do about CO2. The post by Roger Pielke, Sr. illustrates this nicely.
To Carrick: I’ve seen your analysis, and already commented on it. Earlier I looked at real (GISS) data, and found that several adjacent pairs of stations have opposite “climatological” trends. This observation alone establishes that, for the purpose of testing TRENDS and their average, the sampling density is insufficient in accord with established mathematical discipline. This observation invalidates the “correlation” analysis, and I don’t need to present any alternative mathturbation, because the data are flawed from the very beginning, insufficient. Any own or else plot will be garbage. What is so difficult to understand here?
One more time: mo matter how do you massage insufficient data, you cannot get more information out of this data set than it is already. Homogenize it, grid it, select subsets, it does not matter, you will not have any new information. That’s why all your “analyses” show about the same result, which is a garbage predefined by under-sampled wrongly-spaced initial station set. The only way to increase information from the field is to increase sampling density of the data acquisition system. When you do this and get the similar result to your current mathturbations, then you might be up to something.
Smokey says:
February 28, 2011 at 7:30 pm
“Izen gives the latest alarmist talking points in response to mpaul’s list. Off the top of my head I can see some problems with Izen’s responses:
#1: “…the rise in sea level after ~6000 years of stasis and evidence from borehole data indicate the recent warming is a robust signal.” The sea level has been rising since the end of the last global glaciacion, although the rise has moderated. Look closely-[LINK]- and you will see the rise – and the sharper rise since the LIA. [And -1 for using “robust.”☺]”
Perhaps you should respond from somewhere else than the top of your head…
The graph you link to shows the sea level rise at the end of the last ice age… and shows that it has altered little in the last ~6000 years as I stated. The rise over the last century is exceptional within that period of a stable Holocene climate.
“I wouldn’t care so much, but I remember Izen pontificating about how he comes here just to have some fun with skeptics. Having fun now, Izen?”
Lots of robust fun. Especially when skeptics post replies that confirm the points I make.
And can be tweaked by their dislike of ‘robust’ opposition. -grin-
Larry asks: “how can a science that has only about 50 years of satisfactory, reliable measurements … “
You are overly optimistic here. The point I am arguing here is that current measurements are not reliable and do not sufficiently represent the object in space nor in time, and therefore are way far from being satisfactory for the purpose of characterizing climate and its change.
Bruce,
What I’m saying is that you cannot derive a sensitivity from a time series as you have attempted to. Again, if you want to see how it might be done see schwartz’s work and some of lucia’s work. there are other examples as well. If you like I can collect a bunch of papers.
“Average Global Temperature” is completely meaningless. What you want to know is the amount of heat in the system.
Which has more heat, a cubic meter of air at -100 degrees Fahrenheit or a cubic meter meter of water at +31 degrees Fahrenheit.
Carrick says:
February 28, 2011 at 2:54 pm
Wow, did you really miss Espen’s point THAT badly? It has nothing to do with sampling theory and he stated it pretty plainly. Temperature is an INTENSIVE VARIABLE and cannot be averaged as a normal variable, e.g., length. In other words, it doesn’t matter if you have a billion sensors or only two, the arithmetic mean is a meaningless number. Basic thermo 101.
http://en.wikipedia.org/wiki/Intensive_variable
No, temperatures of gases that do not have an identical composition cannot be “averaged,” period. That’s the only problem.
Mark
Or better yet. Which has more energy a cubic meter of air, or a cubic meter of air at 10 meters above and with essentially the same temperature and pressure as the first cubic meter of air?