Anthony Watts has had a number of posts suggesting that solar activity is the primary driver of climate change. It appears that most of the real work has been done by others, including Jim Goodridge, who contributed this one. It provides an almost unbelievable example of how not to analyze data.
Goodridge takes sunspot counts as the basis for his analysis. Sunspot numbers are certainly related to changes in solar output throughout the 11-year solar cycle, and possibly an indicator of long-term changes as well, although there’s some doubt about that; Dr. Svalgaard would disagree, but that’s not the issue here. The issue is what Goodridge does with those numbers.
He provides this graph of sunspot counts (which comes from Wikipedia):
But for data he uses annual averages since 1700, from here, which I’ll plot here:
To make the long-term changes easier to track, I’ve smoothed the data using a wavelet transform. This is what Goodridge chooses to do:
Sunspot numbers since 1700 were plotted as accumulated departure from average in order to compare them with weather variables.
The average for these data is 49.9. So first he’s transforming to difference from 49.9. No problem. Then he plots the accumulation of those values (click the graph for a larger, clearer view):
Problem.
Accumulating values can be an extremely valuable tool for analysis. But they will certainly give a false picture of the overall time evolution of the data. One has to be aware of the behavior of such accumulations in order to avoid misinterpreting the result. But this is what Goodridge concludes from his graph:
The sunspot number index indicates a declining trend for the 1700 to 1935 period and an increase from 1935 to 2008.
You don’t have to be a mathematician to see how wrong this is. Just look at the original data: from 1700 to 1935 there is most certainly not a declining trend. Nor is there an increase from 1935 to 2008. Take another look at the first and second graphs.
What the cumulative sums really show is that for the most part, the data are below average prior to 1935 and above average afterward. While they’re below average, the cumulative difference from average goes down; while they’re above average, the cumulative difference from average goes up. But if we want to know whether or not the data are trending, we should analyze the data, not the cumulative sums.
Let me give an example. Suppose some data follow a perfectly constant linear trend:
Nobody in his right mind would argue what the trend is for this data; it’s increasing at a constant rate from start to finish. Now let’s plot the accumulated departure from average:
Using Goodridge’s method, these data show a declining trend until about 1850, and an increasing trend afterward.
I wish I were making this up.
125 responses so far ↓
dhogaza // March 27, 2008 at 7:06 pm |
oh, c’mon, April Fool’s Day is next Tuesday, maybe they just posted this a week early?
I wish … :(
kim // March 27, 2008 at 7:10 pm |
Check out Pete’s latest graphs in the Svalgaard #4 thread.
========================
J // March 27, 2008 at 7:49 pm |
Tamino, I’ve read enough nonsense over at Watts’s place to last me for a while, so I’m not going to bother reading what Mr Goodridge has to say about this.
But let me play devil’s advocate for a moment.
Suppose you assume that spots on the sun correlate with an increase in heat content (not temperature) on the earth. Suppose you further assume that heat is removed from the earth system at a constant rate, equivalent to the rate at which heat is added when the sunspot number is at its mean.
In that case, when the number of sunspots is above the mean, heat accumulates in the earth system … because it’s only removed at that constant rate. Likewise, when the number of sunspots is below average for an extended period, the earth leaks heat.
In a case like this, where the original variable (sunspots) is correlated with a flux, it may well make sense to accumulate it over time.
The one problem with this approach is that, as Mr Goodridge’s graph shows, accumulated sunspot counts don’t really start rising until the 1930s, whereas we know that the global mean temperature began rising two decades earlier.
In other words, apparently Watts’s blog has proved that global warming causes sunspots.
Congratulations, skeptics! Your Nobel prize awaits you.
[Response: But heat is *not* removed at a constant rate. When it gets warmer, more heat radiates away, and vice versa. So if the input flux is constant the system approaches a new equilibrium, whether that flux is above or below "average." Under your model, if the input flux is above "average" then the heat content increases indefinitely.]
J // March 27, 2008 at 8:42 pm |
Tamino writes: ” But heat is *not* removed at a constant rate. [...] So if the input flux is constant the system approaches a new equilibrium [...]”
Hmpf. You’re trying to show that Mr Goodridge’s model is nonphysical. I’m trying to show that his model establishes that burning fossil fuels increases sunspots. IMHO, my argument is more amusing than yours.
Maybe I’ll change my moniker to Papageno.
[Response: May you find a worthy Papagena.]
>Adam // March 27, 2008 at 8:52 pm |
Just a typo:
“While they’re below average, the cumulative difference from average goes down; while they’re below average, the cumulative difference from average goes up. ”
Above average, it goes up?
[Response: Thanks, fixed.]
Johan i Kanada // March 27, 2008 at 9:08 pm |
Tamino,
He’s integrating the anomalies, which makes sense if you assume a long time constant (a large capacitor, so to speak) in your system. So during times of below average energy influx an energy defecit is built up, and during times of above average energy influx, defecit is gradually reduced and eventually a surplus is built up.
Then, if one assumes that the global temperature is related to the built up energy content, one can perhaps see a correlation. (I haven’t read the article, but I assume this is what is being done.)
This is perfectly ok from a modeling perspective.
However, whether this approach makes sense from a energy balance/physical/climate perspective, I do not know.
But I don’t see that you have addressed that issue?
[Response: Maybe J is integrating the anomalies, but even that assumes an *infinite* time constant, which nobody believes. And it requires the stated condition, that output flux remains constant, which it doesn't. Frankly, I think he was just trying to make a good joke.
But Jim Goodridge doesn't provide any physical model whatever to justify his analysis, while he *does* use it to make assertions about trends in solar activity.
If I myself did that on this blog, how do you think readers would react?]
Brian D // March 27, 2008 at 9:54 pm |
Tamino, thank you. This totally made my week.
I wonder what led to Jim concluding this, given his background. One doesn’t wish to suggest deliberate misleading, but if I were trying to speak to people who didn’t know statistics, and I wanted to generate a plot that looks like an increasing trend (instead of honestly reporting the data), I’d have written something like that post, quickly dropping in the “accumulated” in the description and never mentioning it again.
Also, looking at the full post, he included graphs of solar irradiance and geomagnetic activity. (I have no idea about the latter; the former looks at least ballpark-accurate based on what I’ve seen before.) Without looking at the raw data, I see no clear trend since ~1950 in the solar plot; the geomagnetic one appears noisier but also seems to lack a recent trend, if I had to guess based on (shudder) eyeballing. For some reason (I think we can guess why), Watts says they’re clearly increasing and that this is interesting, when the lack of a recent increase suggests that they aren’t connected to modern warming.
Am I alone in suspecting Dunning-Kruger here (on Watts’ part especially)?
Nexus 6 // March 27, 2008 at 10:18 pm |
I’m often surprised that the most enduringly popular post on my site (according to hits) concerns an awful paper by David Archibald on the very same subject:
http://n3xus6.blogspot.com/2007/02/dd.html
No one in their right mind would even contemplate believing these sorts of analyses I would have thought. But not so – teh internet tubes are full of people spouting this nonsense and invoking the Archibald’s and, no doubt, the Watts’ and Goodridge’s as proof that AGW is a lie and it’s all the SUN.
Some people really, really want to believe.
Johan i Kanada // March 27, 2008 at 10:24 pm |
Tamino,
There is nothing wrong to do what he did, if certain assumptions are valid. Perhaps a constant out-flux is a good enough approximation?
In any case, presumably the purpose was merely to establish a possible connection between the sun’s activities (energy input) and recent warming. No numeric or other further analysis was done, nor claimed (as far as I could see).
Therefore, to ridicule his data analysis seems quite misplaced because he didn’t do any data analysis in the first place, except to show how the “energy bank” balance (due to the sun’s energy input) has changed over time.
[Response: Are you *trying* to embarrass yourself?]
Johan i Kanada // March 27, 2008 at 10:46 pm |
A short review of the Jim/Anthony “thesis”:
i) The objecive is “seeing the solar connection”, nothing more elaborate.
ii) The plot of sunspots “as accumulated departure from average” then indicates the integrated energy input over time. Ok, that can be a areasonable approach(all else being equal).
iii) “The sunspot number index…” is, however, a misleading terminology, as the integrated value no longer is a sunspot index, but a proxy for the earth’s energy balance.
iv) “The eleven-year cycle is clearly visible.” Ok, that could perhaps be true.
v) “An increase in sunspot activity, and by inference, irradiance since 1935 is plainly indicated”. This also seems correct, if by ‘increase’ we mean the integrated value over time.
That’s all.
Apart from the misleading terminology (point iii above), I don’t see what the major problem is.
[Response: If you really can't see what the major problems are, then you're beyond help.]
Johan i Kanada // March 27, 2008 at 11:24 pm |
Tamino, please help me understand what the issues are. Seriously.
[Response: OK. Take a look at Goodridge's graph, and read his account, you'll see a clear indication (and statement) that some change in solar activity -- a rather dramatic and *sudden* one -- occurs in 1935. Now look at the graph of sunspot counts. Is there any sign of a dramatic and *sudden* change in 1935?
Goodridge also claims, and his graph indicates, a rapid and uninterrupted increase in solar influence from 1935 to the present. Again, look at the graph of sunspot activity. Is there a rapid and uninterrupted increase from 1935 to the present?
Now look at the final graph, Goodridge's analysis applied to the artificial data. There's clearly a sharp decline early, a sharp incline late. Now look at the penultimate graph, the artificial data on which it's based; is there a sharp decline early and sharp incline late? Now imagine that the artificial data are *actual* smoothed sunspot numbers. Would that have caused temperature to exhibit an early precipitous drop followed by a late rapid rise?
Even if one bends over backwards to devise some physical model to justify using cumulative sums, like the heat content model mentioned by J, that model turns out to be unphysical -- heat content *cannot* increase indefinitely, time constants are *not* infinite, and output flux is *not* constant. But Goodridge never even bothers to do that. He just uses a transformation of the sunspot data to create a graph which shows what he *wanted* to show: a rapid, uninterrupted rise in the latter part of the 20th century, so he can imply that it's solar activity that's responsible for recent global warming.]
Greg // March 27, 2008 at 11:50 pm |
Johan is right. There is no issue here. He has integrated the energy input (represented via a proxy) as an exercise, assuming constant flux out. A perfectly valid exercise. Watts was suggesting that, under those assumptions, the trend in the accumulated energy is up since 1935. What is your problem? This is embarrassing.
[Response: You're damn right it's embarrassing. You failed the test.]
Greg // March 28, 2008 at 12:10 am |
“Even if one bends over backwards to devise some physical model to justify using cumulative sums, like the heat content model mentioned by J, that model turns out to be unphysical ”
That’s the point Tamino. You’re free to claim that you don’t think the model holds up. But you’re mouthing off about the methodology being wrong. There is nothing wrong in the methodology. Do you understand? If they want to model the earth as a capacitor with a long time constant with a constant flux out, then so be it. Their graphs are right for their model.
Complaining about the validity of the model is a separate issue.
[Response: You didn't just flunk the test, you went for extra negative credit.]
Lee // March 28, 2008 at 12:19 am |
Not to mention – discounting everything else – that it assumes a perfect linear relationship between sunspot number, irradiance, and accumulation of heat energy on earth. That is a necessary assumption for his choice of average of sunspot number over the entire period as a zero point for accumulation or loss of heat energy.
Choice of a different zero point for his cumulative deviations would yield a dramatically different curve. Every maxima or minima on that curve simply reflects a crossing of an essentially arbitrary zero point.
[Response: You *pass* the test, and get extra (positive) credit to boot.]
Andrew W // March 28, 2008 at 12:45 am |
I’m not a mathematician, so I hope this isn’t a stupid question.
If the data set used started in 1750 rather than 1700, this would lift the average count, wouldn’t this in turn change the date at which the sun supposedly started to brighten according to Goodridge’s method?
Harold Brooks // March 28, 2008 at 1:20 am |
I’m not a mathematician, so I hope this isn’t a stupid question.
If the data set used started in 1750 rather than 1700, this would lift the average count, wouldn’t this in turn change the date at which the sun supposedly started to brighten according to Goodridge’s method?
Yes. In particular, if he had included the low values with the Maunder minimum in the 17th century, the series would have trended upward starting ~1720 with a decrease from ~1795-1835, followed by an increase to ~1875 and a very slight decrease until ~1930. The peak at 1795 would have been much lower than the 1875 peak.
Anthony Watts // March 28, 2008 at 1:23 am |
Thank you for the discussion. You raise interesting points. I’ve pointed Mr. Goodridge to your criticisms so that he can respond.
“Capacitor” could be a simple analogy. But earth’s climate system is a good deal more complex than that, and thus calls for a more complex electrical circuit model.
Speaking of responding, will you ever be responding to Steve McIntyre’s many posts regard the weaknesses in your own postings regarding Mann’s MBH98 hockey stick?
That is also a good example of “How not to analyse data”.
[Response: You failed the test too. If you had the guts to admit that Goodridge's analysis is garbage, you might recover a shred of credibility.
McIntyre is entitled to his opinion; I don't happen to agree with it. Neither do Mike Mann, Ray Bradley, Malcolm Hughes, Eugene Wahl, or Caspar Amman. But I can certainly understand your desire to change the subject! Goodridge's post is a gargantuan embarrassment for your blog. It's hardly the first. Nor, I expect, will it be the last.]
cce // March 28, 2008 at 1:24 am |
Somewhat related, David Archibald has been arguing with Leif in his threads on CA. Quite amusing.
dhogaza // March 28, 2008 at 1:44 am |
Even if Mann’s (or HB’s) analysis were wrong, it would be along the lines of missing the bullseye while hitting the target.
While Goodridge’s analysis manages to miss the entire friggin’ planet.
Greg // March 28, 2008 at 1:45 am |
“Choice of a different zero point for his cumulative deviations would yield a dramatically different curve.”
Choice of suitable proxies would yield a dramatically different ‘hockey stick’. In this case, they justify their methodology and use it correctly, and produce what is most likely garbage because the assumptions are incorrect. Much like Mann.
“Choice of a different zero point for his cumulative deviations would yield a dramatically different curve”
Indeed, on this point, the assumption they make in calculating the zero point for the deviations is that the average sunspot activity since 1700 is the ‘equilibrium’ input that produces neither an increase nor decrease in the accumulation of heat. I thought that most of you folks were of the opinion that global average temperatures were largely a flat line from 1700-1900? If so, it’s not such a bad assumption, yes?
[Response: Keep digging that hole deeper.
And by the way, neither Goodridge nor Watts made any mention whatever about any physical model to rationalize the use of cumulative sums. That's just an ex post facto (and rather desperate) attempt to save face.]
Hansen's Bulldog // March 28, 2008 at 1:58 am |
Note to readers: I’ll no longer be responding to every idiot who submits another attempt to justify Goodridge’s “analysis.”
This issue really is a test.
Anthony Watts // March 28, 2008 at 2:13 am |
Always the gentleman, Tamino.
Mr. Goodridge’s analysis may very well be garbage. But he asked me to post it as it was and I obliged. He’s an old friend, and he deserved the same chance to embarrass himself in full public view as you and I do.
Your defense of MBH98 may also be garbage. We’ll see. Science is just as much about being wrong as it is about being right. Being wrong, and even being embarrased, is very useful, because it teaches lessons not soon forgotten.
It is what you learn from being wrong that counts the most.
But at least Jim Goodridge has the courage to put his name to his work.
Like I said, I’ve pointed him to your blog. Please try to be courteous if visits.
[Response: Well that depends on whether or not he avoids trying to change the subject by maligning my opinion of MBH98 like you've done (twice), he disdains your choice to resort to smarmy sarcasm questioning my gentlemanliness, and he omits the lame accusation you made that my choice to blog anonymously is cowardice. If he sticks to the subject, so will I. And by the way, when I do original work I *do* put my name to it -- in the peer-reviewed literature.
With gentlemen like you, who needs ...?]
Greg // March 28, 2008 at 2:25 am |
It’s pretty obvious that I get it.
Goodridge’s graph shows (vividly) that sunspot activity has been consistently above the 1700-2000 average since 1935. You agree of course, since that is what the original graph shows too. It is just showing the same via integration about the mean, for enhanced visual effect. Cry and bleat all you want, there is nothing wrong with the graph, or the process of constructing it.
What I don’t get is why you’re so upset about it. When he said “The sunspot number index indicates a declining trend for the 1700 to 1935 period and an increase from 1935 to 2008″, he was clearly wrong or mistaken and should have referred to the trend in the cumulative, but there is nothing per se wrong with the graph is there?
Surly // March 28, 2008 at 2:35 am |
“But at least Jim Goodridge has the courage to put his name to his work.”
The problem is that “skeptics” keep posting dreck that only the scientists recognize as such.
Case in point — google “solar” and “climate change” and the first hit is the following:
“Solar Variability and Global Climatic Change” by Sallie Baliunas and Willie Soon .
I rest my case.
The denialosphere spins the dreck as proof that current global warming is caused by the sun.
That’s why it matters that dreck is called by its real name.
Greg // March 28, 2008 at 2:57 am |
I don’t think Goodridge’s post was dreck. Apart from that one line Tamino takes such offense at, I find it very interesting that if (and it’s a big if) sunspot activity corresponds to sun energy output then at no time in the past 300 years has so much energy been consistently put out by the sun. That is worth looking at.
Does anyone know what the scientific basis is for the sunspot/intensity link?
Hank Roberts // March 28, 2008 at 3:12 am |
Greg, note the units along the left margin:
http://www.ngdc.noaa.gov/stp/SOLAR/IRRADIANCE/irrad.html
The 3 parts in 1300 difference is from peak to bottom of the sunspot cycle.
Lee // March 28, 2008 at 3:37 am |
Anthony, since you seem to be coming over here, on March 6 in your part 2 post “analyzing” the impact that differing baselines have on the various temp data sets, you said:
“In part 3 of this series, we’ll look at the differences in reporting in more detail.”
In the comments thread for that post , “gravityloss” said:
“Of course, the original post, Part 1, with the different baselines were different and thus the histogram zeros were all over the place, you said this of the GISS data for example:
“Here, we see a much more lopsided distribution in the histogram. Part of this has to do with the positive trend, but other things like UHI, microsite issues with weather station placement, and adjustments to the temperature records all figure in.”
If you are an honest person, you could state that you were completely wrong in the above sentence.
and you responded:
“REPLY: Interesting how you can’t wait for part 3, and immediately say “If you are an honest person….””
In the comments for part 1, published on Feb 27, you said:
“The real question here though is: why does GISS uses a different baseline period than the other 3 metrics?”
and then you said:
“your post is a clear reason for me to close comments until I get caught up and can finish parts 2 and 3. “You could simply link to that and say, oops, I was wrong – the analysis is already done for you.” Yes I could, but I’m going to do it myself, because I want to see and learn for myself.
—
Anthony, you have unretracted false claims in play from that thread – among them that the GISS choice of baseline period is a “real question.”
When pressed at the time to retract your false statements, you said you would be getting to that in part 3. It is now three weeks later, and you have not touched that topic again. You have not been “too busy” as you claimed before – you have posted many threads since. How long does “gravityloss”need to wait with your “Interesting how you cant wait…’ attack hanging there. How long until you tell us why the GISS baseline is a “real question?’
BTW, I’m posting this here instead of at Anthony’s blog, because he has decided my tone is “caustic and condescending” and he’s tired of it, so hes deleting posts that press the issues – and this post is pressing an issue.
dhogaza // March 28, 2008 at 3:41 am |
Then you must be close to a PhD in Learning From Being Wrong.
Actually, no, it was greater in 1950.
Look at the RIGHT graph. Like the one that shows sunspot activity that was posted above.
You’ve fallen right into the trap set by Goodridge.
I actually agree with you. It’s an intentional attempt to mislead, a lie, total bullshit.
Greg // March 28, 2008 at 3:58 am |
Grrr, dhogaza, read my words. I said “consistently put out by the sun”. At no point in 300 years, have sunspots been so consistently above average. That’s what the cumulative graph highlights. By the way, how do you do the nice quoting?
Brian D // March 28, 2008 at 4:31 am |
In some ways, this is a gift that keeps on giving, since it’s indicative of both poor statistics and poor physics. However, it’s not exactly pleasant to recieve said gift. In that regard, I suppose syphilis is a better example.
A quick layman physics/analysis question for Anthony, Greg, Johan, or anyone else who supported Goodridge:
Look at three graphs posted on Anthony’s blog — the first one (Solar Cycle Variations), the second-last one (Solar Irradiance 1611-2001), and Goodridge’s (Annual Sunspot Numbers Expressed as Accumulated Departure from Average (49.9).
(2 points): Using the first graph’s relationship between sunspots and solar irradiance, explain the difference between Goodridge’s graph (sunspots) and the solar irradiance graph.
(2 points): Using the dataset linked above, repeat Goodridge’s analysis (it’s a two-step calculation that can be readily done in Excel) with a different date range for your average (two possibilities I can suggest are the whole dataset, or from the start of the continuous records (around 1750)). What happens to the graph?
(5 points): If you can, please provide an explanation for the physical basis behind making the decision Goodridge did in expressing his data as accumulations instead of raw data. If you cannot, please describe what this analysis accomplishes from a climate science perspective.
I’m serious. I’d love to hear your responses to those, especially that last question, since I can’t answer the first part of it with any physics I know of.
Oh, and an additional question for Greg: I’m asking this because I can’t understand where you’re coming from at all. Please explain to me why the irradiance data (the second-last graph; note that irradiance is what matters most when determining solar impact on climate) has a trend that basically flatlined around 1950, while the global temperature graphs (pick *any* source, really; it doesn’t matter) shows a steep increase from about 1975 onward. That is to say, given the differences in the data, how can you can conlude that the sun’s responsible for modern warming?
I’m not being hostile here, I’m honestly serious.
Eli Rabett // March 28, 2008 at 5:18 am |
The problem is that it depends on an arbitrary choice of an average insolation. Tamino’s point is that Goodridge never thinks about the physical implications of his argument, and if he had, he would have had to admit that it was nonsense. A certain other word that begins with cr occurs, but this is a family blog.
bouldersolar // March 28, 2008 at 5:57 am |
I understand that the data manipulations Goodridge has done doesn’t make sense. But what would you say if his result then correlated well with temperature during a “verification” period after being matched up with a “calibration” period?
John Mashey // March 28, 2008 at 6:00 am |
re: intentional attempt to mislead.
I have no specific data on this one, but:
1) Napoleon:
“Never ascribe to malice, that which can be explained by incompetence.”
2) or any version of the classic aphorism:
“If you torture data sufficiently, it will confess to almost anything.”
3) or my version:
“There’s plenty of Dunning-Kruger Effect to go around, especially in analyzing climate data.”
Mike // March 28, 2008 at 7:20 am |
Methinks though dost protest too much.
Why is it that the skeptic blogs have a civil tone, at least the authors, but the AGW blogs sound like whiny arrogant teenagers?
Who are you trying to convince?
[Response: Hmmm... Watts resorts to flat-out ad hominem, calling me ungentlemanly and a coward. But he uses nice words.
One may smile, and smile, and be a villain still.]
Henry // March 28, 2008 at 8:33 am |
Tamino, I understand your post, but is it possible that Goodridge is demonstrating that his graph of cumulative deviation from average does not reflect a straight line trend? Isn’t that exactly his point?
“”The sunspot number index indicates a declining trend for the 1700 to 1935 period and an increase from 1935 to 2008″”
Isn’t it possible that he is referring to the compression/increased angle of the slope to the right of 1935 to illustrate his point, rather than the fact that it’s ascending or descending? Is it possible that he is calling attention to the fact that in his case the graph is skewed to the right, rather than the perfect “U” shape of your straight line illustration?
In which case would this not be a valid comment?
J // March 28, 2008 at 12:31 pm |
From what I can tell, we have at least two groups of people here, with diametrically opposed viewpoints.
One group suggests that the earth’s climate is a capacitor (Johan), or at least some type of electronic circuit (Anthony). This viewpoint has some advantages, in that we ought to be able to contact the climate’s manufacturer, in Shenzhen or wherever, and maybe get a set of specs for the circuit. That would be handy.
The other group (Tamino, etc.) suggests that the earth’s climate is not in fact an electronic circuit. This is a kind of annoying suggestion, because it means that we can’t realistically expect to reproduce the state of the climate system via a non-physical model doodled on a cocktail napkin.
I think we need to further explore the possibilities of using anti-physical models for studying the climate. I would encourage Mr Goodridge and Mr Watts to write this up for publication in E&E.
J // March 28, 2008 at 12:55 pm |
In this thread, Anthony Watts writes: “Mr. Goodridge’s analysis may very well be garbage. “
That’s odd. When introducing Mr Goodridge’s post on Watts’s blog, Watts wrote: “One of the best and simplest ways of seeing the solar connection is to look at accumulated departure.”
In other words, one of the best ways of “seeing the solar connection” may very well be garbage. Who knew?
kim // March 28, 2008 at 1:15 pm |
At the present state of knowledge, the sun’s interaction with the earth to make climate may well be best understood through the use of metaphor. When you consider how well the models deal with water, and clouds, we’re at a level not much better than metaphor.
Furthermore, metaphors help intuition; and someone’s going to intuit the explanations here, pretty soon.
==============================
Surly // March 28, 2008 at 1:54 pm |
“Why is it that the skeptic blogs have a civil tone, at least the authors, but the AGW blogs sound like whiny arrogant teenagers?”
Perhaps it’s because you agree with the nastyness at those blogs and thus don’t recognize the ad homs and swipes for what they are? From my vantage, the skeptic blogs are filled with them, and a sneering tone on the part of many of the main posters, owners included.
matt // March 28, 2008 at 2:02 pm |
One group suggests that the earth’s climate is a capacitor (Johan), or at least some type of electronic circuit (Anthony). This viewpoint has some advantages, in that we ought to be able to contact the climate’s manufacturer, in Shenzhen or wherever, and maybe get a set of specs for the circuit. That would be handy.
You are aware that engineers (not just electrical) use circuit elements for modeling all types of linear AND non-linear systems: airplanes, fluid flow, water heaters, cereal factory production output, mechanical systems, etc, all can be modeled using circuit elements. And once you have them modeled as a circuit, you can use any range of well known tools for analysis. Check out spice for the most basic version, and simulink for really specialized versions.
I’m not sure what you mean by “anti-physical” models. A capacitor can effectively models any physical element that stores energy. A rock warmed by the sun and cooling at night can be effectively modeled as an RC circuit.
We know the earth receives about 10^21 joules of earth each day and delivers an average temp from that. I’m sure someone here could tell us how long it’d take the earth to reach 66% of the way to absolute zero if the sun burned out tomorrow. Presto. A simple RC model of the earth. Feel free to build from there.
dhogaza // March 28, 2008 at 2:02 pm |
I think the “Goodridge’s graph is garbage” metaphor helps intuition, and I’ve already intuited the explanation for the unbelievable comments we’re seeing posted here in defense of that garbage
Bill Illis // March 28, 2008 at 2:03 pm |
If the sun is a variable star (which it is), then how does that variance affect the Earth’s climate? That is the question you should answer (I guess you already have before.)
Rather than throwing out the flameinator, show how the changes in solar irradiance since 1700 has actually affected the temperature on Earth.
I note that GHGs are predicted to change total forcing by approximately 4 W/m2. The Sun varies by as much as 4 w/m2 over time (or even 8w/m2 starting from the lowest points of the Maunder Minimum cycle versus the highest points of cycle 23 for example).
Divided by 4, solar irradiance changes of up to 8 w/m2 could affect the climate by 0.6C to 2.0C.
Maybe you don’t believe the 8 w/m2. Maybe you only want to assume there is a change of 2 w/m2 from the lowest point of the Maunder Minimum to the highest point of cycle 23. That still results in temperature changes on Earth of 0.15C to 0.5C since 1700.
Maybe we also need to accumulate those solar irradiance changes over a period of time which might also have further affects.
[Response: I certainly don't believe the 8 W/m^2. For one thing, it's really not right to go from the bottom of the Maunder minimum to the *top* of the solar cycle -- you should use the midpoint of the solar cycle. Applying that to the Lean reconstruction of TSI, the difference is about 2.8 W/m^2, not 8. I'm confident that Dr. Svalgaard would claim it's a lot less than that. Then you correctly divide by 4 for the spherical surface of earth, which gives 0.7, but you neglect to account for earth's albedo, so multiply that 0.7 by a further 0.7 -- giving 0.5 W/m^2 difference in solar climate forcing between the Maunder minimum and now, only one quarter the value you ascribe. I'll leave it to the solar physicists to carry on the debate in the peer-reviewed literature.
Regardless, the idea of accumulating solar irradiance departures from average is nonsense.]
Dano // March 28, 2008 at 2:30 pm |
My metaphor for the kim bot is: ‘tap dancing to maintain the ideological position’.
I intuit the kim bot’s grasping at straws to find firm ground on which to tap dance as being an attempt to deny the undermining of the self-identity.
I also intuit that mixed metaphors may be amusing, but what the heck: this thread is inherently amusing anyways. There! I hope I faithfully recreated the kim bot’s coding.
Best,
D
caerbannog // March 28, 2008 at 2:34 pm |
Denier blunders, if nothing else, would make good material for SAT test questions… well, at least SAT test questions that would guarantee that the lowest scores are above 600…
Hank Roberts // March 28, 2008 at 2:36 pm |
Tamino, Google for names +climate if you want to save time. Your site’s now attracting people so thoroughly killfiled elsewhere that they’re starving for attention. Eschew!
kim // March 28, 2008 at 2:37 pm |
One wonders, Dano, why you are so focussed on motive, and not on data.
=======================
Chris Colose // March 28, 2008 at 2:43 pm |
Bill,
You need to convert the TSI change to a radiative forcing. To do this you divide by 4, but also multiply by 0.69 to account for albedo. Theoretically, for RF defined at the tropopause you also include UV absorption in the stratosphere which would further reduce the radiative forcing, as the changes in UV from, say, solar min to solar max is not proportionate to the absolute values of UV: everything else.
If you look at Anthony Watts figure 4 you see just about no trend from 1950-2000. The 11 year cycle is not very significant because of the thermal intertia, and so you need to look at secular trends. If you start from 1900 then maybe 2 w/m^2 of TSI change, which is not even a tenth of a degree temperature change. The IPCC radiative forcings chart (graph here– http://www.realclimate.org/images/ipcc2007_radforc.jpg ) is relative to 1750, but a lot of that is in earlier times and any warming would have shown up already. Some have argued for a very long time lag between forcing and response, but one would expect the rate of warming to drop
with time as the ocean adjusts to the level of forcing, and that’s not happened.
I also have a quick Excel file here with solar data from Lean 2000 for finer detail on the trends.
http://files.filefront.com/CO2+Temp+TSIxls/;9527896;/fileinfo.html
matt // March 28, 2008 at 2:46 pm |
Tamino, you seem to take issue with the notion of “accumulated departure”. You note it’s useful for some types of analysis, but then you highlight why it’s silly in all cases with a contrived example. Huh?
Can you outline why accumulated departure is valid and used in discussing rainfall and temperature as it relates to agriculture output, but not valid when used for looking at sunspots? I get why it’s used for rainfall and ag (level of lakes, growth rates of plants), but I’m not clear why it should be used for sunspots. And Goodridge isn’t clear on that either that I have seen.
Arch Stanton // March 28, 2008 at 2:56 pm |
J, as I understand it the “capacitor” analogy is simply an analogy and the fact that it is electrical is not significant here. Capacitors are capable of building up and storing an electrical charge. The fact that they are primarily used in circuits to discharge power quickly (like a camera battery energizes a capacitor to provide enough power to effectively energize a “flash”) is not necessarily significant in this analogy either. I suspect that a water reservoir may also be a suitable analogy for this discussion. The difference in perspectives as I understand it is whether the capacitor leakage (reservoir leakage, climate radiation) remains constant as the “pressure” builds within the capacitor, (reservoir, earth) or whether the leakage increases to compensate and if so at what rate?
I suspect that someone will be quick to help me out here if I have missed the mark.
J // March 28, 2008 at 3:01 pm |
Matt:
You’re taking this thread too seriously. But that’s OK, I guess.
Yes, highly simplified models can be useful, if they help you understand a system. But when you have a very complex system, drawing conclusions from simple models is dangerous.
In this case, the context is that a huge amount of effort has gone into studying and modeling the earth system. Even people who know a lot about one small part of the earth system (like a marine geochemist who worked on JGOFS) probably doesn’t know enough to comment intelligently on the details of another part (like what are the latest GRACE estimates of mass balance in the EAIS).
I’m not saying that we should just throw up our hands or that there’s no role for amateurs or outsiders in science. I’m just pointing out that a certain degree of humility is in order when you start exploring something that’s not your own field.
Instead of humility, though, what we have here is a community of “skeptics” that (a) mostly is not willing to actually study earth system science; (b) has fixed opinions about the subject; and (c) combines an absurdly high degree of “skepticism” towards mainstream earth system science with a ridiculously low degree of skepticism towards claims that support their preconceptions.
The result is that people develop a fixed idea about something like, say, the role of solar variability in climate change. Then they download some data, play around with it for a while in Excel, and convince themselves that they’ve discovered something new and remarkable. Nearly all the time they’re either doing something stupid (viz., Anthony Watts’s “analysis” of the histograms of temperature anomaly data referenced to different baselines) or just re-inventing the wheel.
I do a lot of this myself, and there’s nothing wrong with it … as long as you don’t take it too seriously, and don’t start imagining that you’re Galileo and the IPCC is the Inquisition.
In the case of Mr Goodridge’s post over on Watts’s blog, he doesn’t seem to have a clear understanding of what model he’s suggesting (or if he does have such an understanding, it isn’t explained). He plays around with numbers in ways that don’t really make sense from a physical perspective.
Why would the arithmetical average of sunspot data over some particular time period happen to precisely define the transition from the earth accumulating heat to the earth losing heat? Why are there no negative feedbacks, such that a constant flux into the system leads to a constant accumulation of heat, without a counterbalancing loss of heat e.g. Stefan-Bolzmann? Etc. etc. etc.
Finally, by Mr Goodridge’s own model, the increase in accumulated sunspot counts begins a couple of decades after the beginning of the rise in global temperatures. As I said at the top of the thread, if Mr Goodridge insists on ascribing causation to this correlation, the natural conclusion is NOT that sunspots cause warming, it’s that global warming causes sunspots.
If that isn’t enough to give people pause, I don’t know what would be.
george // March 28, 2008 at 4:10 pm |
Yes, like what we learned when the Mars spacecraft burned up because of a simple metric/English conversion error.
Or, what we learned (and then ignored) when the first space shuttle exploded, because NASA officials ignored problems that they had been told were potentially fatal (and later also ignored, which led to the second disaster)
So much important learning to do and so little time!
David B. Benson // March 28, 2008 at 4:36 pm |
matt — You’ll do a lot better to consider the physics and use the Stephan-Boltzman black body radiation approximation. Rather far from a linear RC circuit analogy.
Stick with the physics.
george // March 28, 2008 at 5:10 pm |
If I accumulate enough sunspots, do I win the Global Warming Denial Bingo game?
Or perhaps it’s really a poker game? –”I’ll see your 100 sunspots and raise you 100…”
What’s the Prize? A barbecue at the Marysville, CA surface weather station?
caerbannog // March 28, 2008 at 5:14 pm |
Rather far from a linear RC circuit analogy.
The rc-circuit argument reminds me of that old saying,
“When all you have is a hammer, you tend to view everything in life as a nail.”
If nothing else, this thread demonstrates that taking cookbook “plug and chug” engineering classes in college does not make one qualified to critique the work of professional climate-scientists.
dhogaza // March 28, 2008 at 5:14 pm |
This accident happened because administrators didn’t listen to some of their experts.
Not a great precedent for the denialist insistence on trying to get politicians to ignore their scientific experts…
matt // March 28, 2008 at 5:16 pm |
David Benson: Stick with the physics
Not disagreeing, just merely pointing out that all sorts of linear and non-linear systems are routlinely modeled using circuits. A previous poster (“J”) seemed to believe this was rediculous.
As to your suggestion that Stephan-Boltzman is the solution, that of course tell the you change in temp at T>=6+ time constants (steady state). What we are debating here is changes in temp at many fewer time constants, hence it is critical to look at the energy storage capability of the system and rate of change. And lo and behold, what is an easy way to solve that? You could write discrete time simulations in C or Fortran, which is what climate models are doing, or you could use a different notation (circuits) and rely on tools such as spice to solve your linear, non linear transient and steady state responses. One isnt’ more right than the other. It’s just what you known.
It’s all physics, trust me. It might not be familiar to you….
L Miller // March 28, 2008 at 5:25 pm |
[blockquote]
1) Napoleon:
“Never ascribe to malice, that which can be explained by incompetence.”
[/blockquote]
Grey’s Law:
“Any sufficiently developed incompetence is indistinguishable from malice.”
Johan i Kanada // March 28, 2008 at 5:42 pm |
Tamino,
Regarding your statement: “Regardless, the idea of accumulating solar irradiance departures from average is nonsense”:
- Actually, it isn’t. If the assumption is that the outflow of energy is constant, or at least varies much slower than the inflow, then the integrated inflow will indicate the energy content in the athmosphere, which, I would assume, is related to temperature.
- Perhaps the assumption above is incorrect, I don’t know. But, nevertheless, it is a valid and not terribly strange assumption.
- Integration and derivation of variables, is, as far as I can tell, pretty common in science… so to flat out say that is is stupid seems a bit hasty.
J,
Regarding your statement “One group suggests that the earth’s climate is a capacitor (Johan)”:
- That is not what I suggested. Read & understand, before you write.
Brian D,
Regarding your statement “(5 points): If you can, please provide an explanation for the physical basis behind making the decision Goodridge did in expressing his data as accumulations instead of raw data. ”
- See e.g. my original ‘capacitor’ comment. Under certain assumptions, it makes perfect physical sense.
- Note also that this is not exactly a top-notch scientific article, neither did it pretend to be. Hence, many assumptions & explanations are missing, and, of course, there is no quantitative analysis at all.
Tamino,
Regarding your statement: “And by the way, when I do original work I *do* put my name to it — in the peer-reviewed literature.”
- What is that name? I would like to check out your work, if that’s ok.
(Never mind our differences of opinion sometimes, I do think you’re a good writer (at least here), and, hopefully, your papers are equally well structured and easy to read.)
David B. Benson // March 28, 2008 at 5:49 pm |
matt — You were the one to suggest the thought experiment of ‘putting out the sun’ and then letting earth’s temperature relax; yoou proposed an RC analogy. I simply pointed out that Stefan-Boltzman requires non-linear heat loss.
Probably one could model this in spice, but you ought to be able to analytically solve such a simple non-linear problem.
Dano // March 28, 2008 at 6:01 pm |
The kim bot routine outputs in misdirect mode: One wonders, Dano, why you are so focussed on motive, and not on data.
The vast majority of humans on this planet have moved beyond considering denialist tactics of inflating crumbs into huge picnics, replete with all the world’s important dignitaries as guests.
Rather, the rest of the planet has moved on to learning how to discuss how society adapts and mitigates. Denialists are the waving, shouting little group left behind on the dock, wondering where the societal ship is sailing to. Do they shout ‘bon voyage!? Sadly, no.
Someone should re-program the kim bot reply routine to a more updated response mode.
There! How’s that for metaphor as discursive option?
Best,
D
RomanM // March 28, 2008 at 6:17 pm |
Might as well risk showing my statistical ignorance and throw $.02 into the mix. You did a smoothing using wavelets and presented an example which you claimed made the entire graph under discussion become nonsense. However, you didn’t offer any interpretation of what the graph could tell you. Perhaps, I could suggest something in that direction. Since you have the blackboard and the chalk, I will have to describe my example in words.
Suppose that I have a thermometer in a building with an adjustable heat source. At various time intervals, someone comes along and increases or decreases the setting on the heat source. The heat source stays constant between these changes. What would a graph of the temperatures on the thermometer look like? Since the temperature does not immediately jump to a new level and stay there, it will rise or fall at a roughly constant rate, a straight line – the rate would depend on the ambient external temperature and the insulation present in the building. Could you tell the times at which the changes were made by looking at the temperature graph? Look at the places where the graph bends. Below “average” settings correspond to negative slopes, above “average” to positive. It seems to me it might be a not-so-bad method for eyeballing change points for shifts in a stationary process. Slower continuous changes would cause the line to be somewhat curved rather than straight In the graph. Reading the graph in this manner, it appears that jumps could have occurred in the sun spot frequency at least six times during the period shown. The latest one does appear to be about 1935. Your wavelet smoothing example on the other hand would oversmooth the jumps and not offer a very good story of what had actually occurred nor when the changes happened.
I agree with you that the graph does not show a “declining trend” from 1700 to 1935 – that was a poor choice of words – but the slopes and the relative straightness of the curve over longer time periods do indicate the changes do appear to be pretty sudden and that (except for the period from about 1760 to 1790) the level of sunspots since 1935 has been quite a bit higher than prior to that time. The actual argument should not be whether the graph is “nonsense” since there is a lot of information contained therein if you know how to interpret it. Creating a side show does however have the advantage of avoiding the underlying issues for which the graph was created, i.e. whether there is a cumulative effect on temperature from changes in the sun as proxied by the sun spot frequency.
[Response: First and foremost, *all* the folks who are trying so desperately to justify Goodridge's post need to stop kidding themselves. Goodridge uses his analysis to imply a rapid and nonstop upward trend in solar activity from 1935 onward. Referring to his graph he says, "The sunspot number index indicates a declining trend for the 1700 to 1935 period and an increase from 1935 to 2008", and then says, "An increase in sunspot activity, and by inference, irradiance since 1935 is plainly indicated." This isn't a "poor choice of words," it's a crystal clear statement of exactly what he's suggesting. Any subsequent claim he might make that it's an investigation of the cumulative impact of solar increase will be nothing more than an ex post facto attempt to save face.
Now consider your heat source example. I come along and kick the heat source up ten units. Will the temperature increase at a constant rate *forever*?]
Lee // March 28, 2008 at 6:22 pm |
JiK:
“If the assumption is that the outflow of energy is constant, or at least varies much slower than the inflow, then the integrated inflow will indicate the energy content in the athmosphere, which, I would assume, is related to temperature.”
There are a lot of known invalid assumptions in that, but a key assumption is the choice of arithmetic average as the ‘zero point’ above which energy accumulates, and below which is dissipates. That choice is arbitrary and unsupported. For it to be correct, there has to be a perfetlly linear connection between sunspot number, irradiance, and energy accumulation on earth. We know that there are lots of nonlinearities i energy accumulation from irradiance on earth, just for starters.
For that choice to be correct, the time period over which the arithmetic average is calculated also needs to be sufficient long to ‘zero out’ all the noise. The fact that changing the ends of the time period by only a decade or two would dramatically alter the analysis tells us directly that this is very, very unlikely to be true.
Choosing another ‘zero point’ even by a moderate amount and applying the same analysis would give a completely different looking curve with the slope of large swathes changing sign altogether. That fact alone tells you all you need to know about this analysis.
matt // March 28, 2008 at 8:15 pm |
J: You’re taking this thread too seriously. But that’s OK, I guess.
See my previous question to Tamino. I don’t understand why Goodrich uses accumulated departure. To me, THAT is the area Tamino should have addressed. Instead Tamino opted to rain all over the accumulated departure technique as a whole with a contrived graph that failed to address the root issue.
My second point was simply that physical systems can and are modeled using circuit elements all the time. It’s not news. You (and others, albeit perhaps tongue in cheek–sorry if I missed that) seemed to imply the technique wasn’t at all valid.
Johan i Kanada // March 28, 2008 at 8:27 pm |
Lee,
Sure, the averaging is not correct, the reference level should be the equilibrium level. Anything above builds up energy, anything below decreases it.
So assume that we find that equilibrium point. Then the integrated deltas will then indicate the energy level in the athmosphere (again assuming all else stays constant).
Johan i Kanada // March 28, 2008 at 8:42 pm |
Tamino,
Regarding your statement “Any subsequent claim he might make that it’s an investigation of the cumulative impact of solar increase will be nothing more than an ex post facto attempt to save face.”
- You’re being too negative. The integration is ok (in principle), and it is clear that he indeed intends to an integration. So that is not a problem.
- Generally, though, the essay lacks clarity and gives a sloppy impression. (E.g. the wording used.)
matt // March 28, 2008 at 8:44 pm |
caerbannog If nothing else, this thread demonstrates that taking cookbook “plug and chug” engineering classes in college does not make one qualified to critique the work of professional climate-scientists.
Ah, yes, plug and chug. There’s a reason a fresh engineering grad with BS out of a good school starts at six figures, and there’s a reason a good engineer with 15 years of experience can routinely make $250,000 a year with bonus and options. Not bad for plug and chug, eh?
But I’m sure it also is satisfying having a PhD and working as an associate professor for $50K/year and holding office hours for so that the kids can get some free help with homework. Or maybe working for the government for 10 years to hit $90K/year researching, uh, climate models.
Seriously, you discount so much that engineers have done in the last 100 years….what a shame. Luckily, the market decides salaries and not you.
sod // March 28, 2008 at 8:57 pm |
Instead of humility, though, what we have here is a community of “skeptics” that (a) mostly is not willing to actually study earth system science; (b) has fixed opinions about the subject; and (c) combines an absurdly high degree of “skepticism” towards mainstream earth system science with a ridiculously low degree of skepticism towards claims that support their preconceptions.
The result is that people develop a fixed idea about something like, say, the role of solar variability in climate change. Then they download some data, play around with it for a while in Excel, and convince themselves that they’ve discovered something new and remarkable. Nearly all the time they’re either doing something stupid (viz., Anthony Watts’s “analysis” of the histograms of temperature anomaly data referenced to different baselines) or just re-inventing the wheel.
wonderfully written.
people defending the post should do more READING and less interpretation.
this is part iof a series of completely false posts on Anthony’s blog. my advice to him is to learn to admit errors and to tolerate comments “sceptic” to his writing. it would allow errors to be discovered eralier and really allow some learning from them.
Erik i Sverige // March 28, 2008 at 9:00 pm |
This is really wierd. One or two years ago there was this romour in the denialosphere that the climate research community ignored the Stefan-Boltzmann law. Now these people themselves *truly* ignores SBL.
And then there was this thing about the time constant with was claimed to be overestimated. Now, they claim that the time constant is frigging *infinity*. I guess that if you truly believe that there is no AGW, any argument is better than no argument.
dhogaza // March 28, 2008 at 9:01 pm |
Well, by this rationale, professional athletes must be far more important to society than engineers.
Maybe we should let them decide whether or not climate scientists are correct, they’re clearly several times more qualified to do so than engineers.
Layman // March 28, 2008 at 9:03 pm |
J, you are seemingly unaware of analogue computer modeling. Analogue modeling can often produce far superior representations of physical systems than digital modeling. And, are you suggesting that somehow digital computer models (like those used by Mann et. al.) are … physical ??
Mike B // March 28, 2008 at 9:06 pm |
Has anyone explained how this cumulative energy deficit which bottoms out in 1935 caused the earth to start warming almost 25 years earlier?
I think J’s assertion makes more sense, global warming is causeing the sunspots. :-)
Dano // March 28, 2008 at 9:09 pm |
Seriously, you discount so much that engineers have done in the last 100 years….what a shame. Luckily, the market decides salaries and not you.
The “market” “decides” teacher’s salaries too. We see how well that’s working out, evidenced by this thread. I guess the “market” fails now and again, eh?
Nonetheless, the point is that injuneers may have a tad bit of ego about their abilities. Present company excepted, of course.
Best,
D
caerbannog // March 28, 2008 at 10:05 pm |
Ah, yes, plug and chug. There’s a reason a fresh engineering grad with BS out of a good school starts at six figures, and there’s a reason a good engineer with 15 years of experience can routinely make $250,000 a year with bonus and options. Not bad for plug and chug, eh?
You are cherry-picking salary data in the same manner that you cherry-pick climate data.
Unless you are a “superstar” engineer, you are going to be making a lot less. Competent “journeymen” engineers with 15 years of experience typically make far less than 250K/year in salary/bonus/stock-options.
A top-of-the-class Stanford/MIT/CalTech grad working in the Silicon Valley will pull in “superstar” bucks, but that’s hardly the norm for the engineering profession.
Bill Illis // March 28, 2008 at 10:16 pm |
Since accumulated departure is fraudulent “nonsense”, (I’ve noticed the usage of this word is accumulating) we should also throw out all accumulated GHG forcings, accumulated CO2 in the atmosphere, accumulated land-use changes etc.
Obviously, there is room for some type of kind of accumulation. If there was absolutely no solar irradiance accumulation, then the Earth’s temperature would rise and fall with the daily changes in irradiance (which can be quite significant) as well as with the 11 year solar cycle.
S2 // March 28, 2008 at 10:39 pm |
I love Goodridge’s graph (and his conclusions).
Not only does it show that the “Little Ice Age” was warmer than most of the 20th Century, it also demolishes the “global cooling between 1940 & 1970″ argument.
Hilarious.
It reminds me of Lewis Caroll:
(The Hunting of the Snark)
David B. Benson // March 28, 2008 at 10:53 pm |
Bill Illis stated “… the Earth’s temperature would rise and fall with the daily changes in irradiance (which can be quite significant) as well as with the 11 year solar cycle.”
I assume you referring to something other than day/night. I know nothing about this.
But the change in irradiance over the sunspot cycle is about 3 parts in 1300. The climate surely responds to this, but its so far down in the noise as to be undetectable, AFAIK.
[Response: Actually it's only about 1 part in 1300.]
S2 // March 28, 2008 at 10:56 pm |
From Watts Up With That?, dated 18-Feb-2008:
Check out the Dalton Minimum on Goodridge’s graph.
Lee // March 28, 2008 at 11:40 pm |
They’re actually debating what they’re going to name the coming ‘minimum’ – “Watt Minimum” has been suggested several times. It has been said over there also that the current warm spell should be named the “Gore Maximum” so that the ‘warming fraud’ is associated with his name forever.
It’s quite amusing, if sad.
S2 // March 29, 2008 at 12:00 am |
I think this is true over a single cycle – it’s back to signal/noise ratio over short (11 year) periods again. The TSI difference between a solar maximum and a minimum is around 1.2 W/m2, or about 0.1%.
I have read (and I’m sorry, I can’t remember where) that feeding a 0.1% variation in TSI into GCMs gives a response of about 0.1 degrees C.
There’s an interesting paper by Camp & Tung http://www.amath.washington.edu/%7Ecdcamp/Pub/Camp_Tung_GRL_2007b.pdf.
They look at it from a longer timescale, and arrive at a figure a little above the GCMs (but the error bars overlap).
Bill Illis // March 29, 2008 at 12:47 am |
The Nimbus and Acrim satellites have measured changes in solar irradiance of as much as 5 W/m2. Check the charts and data linked to by others.
The percentage difference in the solar cycle average trend from the long-term trend (0.1%) is nonsense if you are trying to say the accumulated departure is also nonsense.
AcrimII recorded irradiance as low as 1363 W/m2 and irradiance as high as 1368 W/m2.
[Response: Get serious. The PMOD composite, as an example, records TSI as low as 1361.8 W/m^2 on Oct. 29, 2003, during a dip below 1364 W/m^2 which lasted for an entire TEN DAYS. Your talk about changes as much as 5 W/m^2 is an attempt to mislead readers into the impression that those ephemeral fluctuations are representative of the solar cycle influence on climate. THAT is nonsense; that figure is nothing like the amplitude of the solar cycle, which according to satellite measurements is just about 1.0 W/m^2.
Yours is exactly the kind of misrepresentation of *reality* which I will *not* allow to poison the dialogue. Straighten up and fly right or get the hell out of here and don't come back.]
Heretic // March 29, 2008 at 1:22 am |
To Kanada and all the others bugging Tamino to divulge his name: drop it. Tamino has already commented once on the personal threats made against him, a subject he has not brought up again, but nevertheless is reason enough to keep going by HB or Tamino. As for those suggesting that the tone here is worse than on the denialist blogs, please say it again, I had such a laugh out of that.
JimV // March 29, 2008 at 1:47 am |
“… a good engineer with 15 years of experience can routinely make $250,000 a year with bonus and options”
Huh? I’ve worked as an engineer (M.M.E.) for 38 years and never met or heard of a working engineer (non-manager) who made more than 140K. The average at GE for an engineer with 15 years experience is about 80K, and they show us industry salary statistics which imply that they are being generous (not that I accept that without several grains of salt, but still).
Personally, I would have taken a salary cut to go into science, but I wasn’t sure I would be any better than mediocre at it. I have five GE engineering-recognition awards and one award from a national engineering journal (but who’s counting?), so I think I could call myself a good engineer. Science rules.
(Sorry about the off-topic rant. Probably both this and the comment that set me off should be deleted to improve the signal-to-noise ratio.)
steven mosher // March 29, 2008 at 2:33 am |
TCO.
Can you please keep the guys on the denialist side from offering alternative wacky theories based on the sun? denial doesnt mean offer wacky theory instead.christ!
If your opponent offers up an untested theory, thats no reason to offer up a wacky one.
It annoys me more than the notion that a dozen magical BCPs can reconstruct the worldwide climate of the last 2000 years or so.
Clone them treemometers.
( tm Moshpit)
TCO // March 29, 2008 at 3:08 am |
Lee:
Watts is not just late with “part 3″. He’s also late with the wrap up of his painted shelter studies.
I’m really getting sick of my fellow skeptics starting blogs instead of writing papers. Putting cherry-picked, initially found, selective criticisms (meant to imply more) into the record.
What a bunch of ass-lickers.
dhogaza // March 29, 2008 at 3:26 am |
Oh, actually I think it does … skepticism, no, but denialism, certainly.
Maybe you guys should smarten up and recognize that there’s three sides …
Science …
Skepticism …
and Denialism …
With the wackiness quotient increasing as you move down the list.
[Response: I'd include "skepticism" as an essential ingredient of science. But skepticism doesn't mean believing nonsense garbage, any more than an open mind does. I get the impression that maybe steven mosher and TCO are as frustrated with this junk as I am.]
Bill Illis // March 29, 2008 at 3:32 am |
The Acrim data is here. The chart is on the home page and shows the variance of irradiance recorded by Acrim which will confirm the figures I quoted.
http://www.acrim.com/
The point is if the irradiance is as low as 1,363 W/m2 on July 23, 1997 (confirmed in the chart and in the data tables) and as high as 1,368 on August 20, 2003, the temperature on planet Earth does not directly reflect those extreme changes in the daily irradiance.
There must be an accumulation period or an averaging over a period of days, weeks, months or years, however, which affects the temperature.
[Response: What you originally said was, "The percentage difference in the solar cycle average trend from the long-term trend (0.1%) is nonsense," and you used that 5 W/m^2 difference to support that idea. Well, the 0.1% solar-cycle average is CORRECT. As for comprehending satellite data, go read this post and pay special attention to this graph, especially graph "b" of that figure.
Then, think carefully about the difference between "accumulating" and "averaging."]
Eli Rabett // March 29, 2008 at 3:45 am |
Bill, CO2 accumulates, so does the associated forcing. Sunlight does not
Greg // March 29, 2008 at 4:28 am |
“That is to say, given the differences in the data, how can you can conlude that the sun’s responsible for modern warming?”
A strange question aimed at me Brian, seeing as how I never said anything of the sort, and a cursory reading of my posts shows that I never supported the model (I described it as garbage), just the methodology. Goodridge took accumulated departures from the mean, which vividly showed that solar spot activity has been consistently above average since 1935. That is the truth. Tamino attacked the construction of the graph, when in fact there is nothing wrong with it, or the idea of creating it. You can (rightly) attack the idea that the graph has any real significance, and it has been ably done in this thread, but that’s not what Tamino did in his initial post is it?
[Response: No, that's not what Goodridge did! If that was his point, then you don't need cumulative sums to establish it -- just look at the graph of smoothed sunspot numbers. But Goodridge was quite clear (read his own words!) -- he uses the graph to claim a declining trend from 1700 to 1935 and a dramatic increase from 1935 to the present.]
Timothy Chase // March 29, 2008 at 4:33 am |
Bill Illbis wrote:
Bill, for anyone who is the least bit familiar with the concept of radiative forcing, you have just demonstrated that you haven’t the foggiest. Forcing isn’t an accumulation: it is a differential between what radiation is enters the climate system and what radiation is leaves the climate system at the top of the atmosphere. Add more carbon dioxide to the atmosphere, you increase the opacity of the atmosphere to infrared radiation (but not to visible radiation), and therefore you decrease the rate at which the earth is able to radiate thermal radiation into space. But leaving solar irradiance constant (as it more or less has been – neglecting the solar cycles – best estimates – for more than half a century), the climate system will heat up and continue to heat up until the rate at which thermal radiation is emitted compensates for the increased opacity of the atmosphere.
As for “accumulated CO2,” just about anyone can understand that we are able to measure the parts per million of CO2 in the atmosphere and that by direct measurements we are able to show that it has been going up since 1959 and that it accelerated during the 1970s. Likewise, we are able to show that the oxygen content of the atmosphere has been diminishing — in the expected proportion with the combustion of fossil fuel. Likewise, we are able to image the increased opacity of the atmosphere in those parts of the spectrum in which carbon dioxide absorbs infrared and thereby measure carbon dioxide’s concentration at different temperatures, pressures and altitudes. And we are able to do the same with water vapor and methane.
Bill Illbis wrote:
Latent warming (principally due to thermal inertia and ocean circulation) necessarily decelerates over time, assymptotically approaching a new equilibrium. However, global warming has accelerated since 1978. Ergo, the primary cause of current warming cannot be solar. And regardless, watts per square meter, whatever climate sensitivity there is to solar variation, the sensitivity will be essentially the same as that due to the backradiation that results due to greenhouse gases increasing the opacity of the atmosphere to thermal radiation. And watts per square meter, the increase due to anthropogenic greenhouse gas backradiation has been greater — pretty much since 1881 relative to 1880, NASA GISS best estimates.
matt // March 29, 2008 at 5:57 am |
The “market” “decides” teacher’s salaries too. We see how well that’s working out, evidenced by this thread. I guess the “market” fails now and again, eh?
Here in Seattle, we spend just under $10,000 per child on education. So a class of 26 has a budget of nearly $260,000. My child’s classroom is about 600 square feet. Commercial real-estate in a nice area and a nice buidling is $40/ft2. That’s $24K/year for a building with granite and marble appointments–typically what you’d see a law firm rent. And it’s with parking. $400/child for new books is another $10K. Let’s give them each a free box lunch everyday from an upscale sandwich shop at $10/day. That’s $9K/year. And let’s include a $200 medical physical for each kid once per year. That’s $5200.
That’s $260K – $24K – $10K – $9K – $5 = $212K left. Let’s add in a teacher’s helper for $40K year. Let’s pay the teacher $100K/year. That’s $72K left for administrators and tutoring and perhaps a few months of 1:1 music lessons.
There’s plenty of money there for teachers. The former teachers that are now administrators are holding out on their brothers and sisters. That’s too bad.
matt // March 29, 2008 at 6:15 am |
You are cherry-picking salary data in the same manner that you cherry-pick climate data.
Unless you are a “superstar” engineer, you are going to be making a lot less. Competent “journeymen” engineers with 15 years of experience typically make far less than 250K/year in salary/bonus/stock-options.
Which climate data are you referring to?
Of course we’re talking about good enginers. But not necessarily great engineers. I’m sure most here have an opinion about engineers at Microsoft. Here’s their salary scales: http://www.washtech.org/news/industry/display.php?ID_Content=5041
A software tester (“SDET”) will start at about $67K. Note these testers don’t write code in the product, they TEST the product. They might write code to help test the product, however. A run-of-the-mill software developer or program manager starts at level 59. Solid hires from Standford or Waterloo will start at level 60 (still with just a BS), and you can see the top of that band is $100K. A developer leading a team of 1-2 folks is usually a level 63 or 64. A good developer will hit level 63 or 64 in 6 years. A developer leading a team of 10-15 is level 65 to 66. About 1% of Microsoft’s 90,000 employees are supposedly >=68. That’s about $150 base, plus another $300K in stock and bonus bonus as the Seattle Times uncovered a few years ago.
And Microsoft pay is LOW. Google is quite a bit more. And you can find a host of companies that have lured employees from Microsoft on salary alone. Otherwise, Microsoft wouldn’t have 3000 job openings at any point in time.
Every company I’ve worked at told me my salary was super competitive. There’s only one way to find out for sure….
Anyway, feel free to have the last word on salary. My point is that a good engineer can easily find amazing compensation compared to a good scientist. And this assertion was in response to someone that thought engineers simply “plug and chug”. There’s a very valid reason engineers are paid more than scientists.
Hank Roberts // March 29, 2008 at 10:18 am |
> “Watt Minimum”
Sometimes all you can do is stand back, watch, and wave as people sail off the edge of the world.
Barton Paul Levenson // March 29, 2008 at 11:46 am |
Bill Illis writes:
[[If there was absolutely no solar irradiance accumulation, then the Earth’s temperature would rise and fall with the daily changes in irradiance (which can be quite significant) ]]
The Earth’s temperature does rise and fall with the daily changes in irradiance. The different sides of the curve are called “day” and “night,” respectively. On average, temperatures are higher during the “day” and lower during the “night.”
sod // March 29, 2008 at 11:57 am |
could we please stop this moronic salary discussion?
unless you want to demonstrate that drawing any conclusion from salary on competence or knowledge IN A DIFFERENT FIELD is absolutely idiotic!
a quick look at some real data shows within seconds that our denialist friend is in denial of reality on the topic of wages, as he is on climate science.
http://www.eweek.org/site/News/Eweek/99salcompar.shtml
http://www.bls.gov/oes/current/oes_nat.htm
L Miller // March 29, 2008 at 4:00 pm |
If you were to track E(in) – E(out), accumulation would be a valuable tool because it tells you how E(total) in the earth system is changing and this directly relates to temperature. There is even a significant lag of 10-30 years due to the capacity of the ocean to hold heat, which is the built in warming that’s often discussed.
For accumulation to have meaning you need a physical model where outgoing IR = E(out) is constant. Furthermore, not only does it have to be constant, that constant value is directly related to the zero point used for the accumulation.
While you could build in “Capacitance” to hold E(out) somewhat constant, this would also hold temperature constant because E(out) = IR(out) which is directly related to temperature. In fact the assumption of a constant zero for the accumulation means that temperature must also be constant because anything that could hold E(out) constant would also force a constant global temperature.
Or you could visually inspect the data and see that what was being done made no sense.
RomanM // March 29, 2008 at 6:47 pm |
I don’t like to leave questions unanswered nor statements deserving a rebuttal hanging around.
No I would not expect the temperature to increase *forever*. There is certainly an expectation that given sufficient time the temperature would approach an equilibrium if the heat source was unchanged. However, whether there was 65 seconds or 65 hours or 65 years would be a function of many other variables in and around the building (the large indoor pool, the indoor skating rink, etc.). In my opinion, that is where the argument should be centered and not on a myopic view of such a graphical technique. I notice that you seem to have started a thread in that direction.
Lee (with similar agreement from Eli R.):
Did you think through what actully happens to the curve when such changes are made? It really isn’t that hard. Start with a sequence, center the sequence at its average and form the partial sums. Plotting this gives a curve with bends at various places with the property that the starting value (before the first term) and the end value of the curve are both zero. If we take a contiguous subsequence of the original centered values and form the partial sums, the resulting plot looks exactly like the original section of the curve formed by that subsequence except for possibly having been shifted up or down. The same effect happens if we start with a constant time “0″ value and then add the individual series values to the current total one at a time. A change in the centering value corresponds to a “rotation” of the curve (centered at time “0″) – the bends would still be at the same places but the slopes of the lines between the bends would be altered. So you think this is an undesirable property?
Let’s continue the “suppose” in my earlier post. Suppose that I wish to estimate the temperature in the building (where the heat source is being turned up and down). At regularly spaced intervals, I go over and record the current setting on the heat source control. Plotting the raw data doesn’t give me a clue as to how the temperature might have fluctuated so I center using the average and form the partial sum sequence. Does this look like the temperature curve? Probably not since my data has not been “calibrated” to the actual temperatures. The bends may tell me when changes occurred, but the slopes only represent relative setting values. The simplest calibration might depend on three parameters: the actual starting temperature, the actual final temperature and a scale parameter. The first two parameters will correspond exactly to a shift and a rotation of the type referred to above. And yes, a slope could conceivably change sign since a zero slope now indicates that the setting is the one at which the added heat is exactly enough to balance the heat that is being lost thus leaving the temperature constant and not as in the uncalibrated sequence merely a value equal to the weighted average of the various heat settings. Completely different? A ridiculous technique? I don’t think so.
Lee // March 29, 2008 at 9:24 pm |
TCO,
Anthony just sent me a private email saying he is no longer going to post anything I say “on the issue” until he posts part three – which he will get to when he gets to it.
It seems he sent this as ‘explanation’ for why he cut my post responding to his incredibly insulting diatribe about anonymous posting. The entire place over there has descended to vituperation and snark, and Anthony is leading the charge. I’m done with him.
TCO, if everyone on “your side” keeps doing that kind of thing instead of doing good science, perhaps that should be telling you about the validity of the arguments on “your side?”
TCO // March 29, 2008 at 10:20 pm |
It’s pretty disappointing.
Lee // March 30, 2008 at 1:08 am |
Oh my, oh my…
Anthony is removing comments from his threads, after he approved them and responded to them and they have been up for a while, without note.
He has removed my comment in the Al Gore thread asking him where part three is, and he has removed his insulting response to it in which he called me hypocritical. Poof – gone.
I looked back at parts 1 and 2 of the “histogram” series – None of my comments are left in part 2. Poof – gone. Most of my comments are removed from part 1.
Gosh. And he wonders why I’m not jumping to write a top-post article for him. In fact, he called me hypocritical for not agreeing to do so – before he removed that comment without apology. Please excuse me for openly laughing at him now.
[Response: I just went to look again at part 1 of the histogram series. But all I got was the message, "Error 404 Sorry, but you are looking for something that is not here"]
kim // March 30, 2008 at 1:28 am |
Lee, he offered you a forum; you sneered. You’ve got little cause to complain now.
=============================
[Response: Disappearing comments. Disappearing replies. And it would now appear, disappearing posts.
Any bets on when Watts' post on which this post is based disappears?]
Lee // March 30, 2008 at 1:48 am |
kim, I have no intention whatsoever of associating any of my work with Watt’s reputation. I pointed him at other existing work which does a better job that I would of explaining what he asked, and told him I had no intention of repeating that work. For that, he called me a hypocrite. I’m not complaining, I’m laughing at him.
Lee // March 30, 2008 at 1:53 am |
Tamino, you’re right. I just surfed back through the threads, and both part 1 and part 2 are gone.
Hansen's Bulldog // March 30, 2008 at 2:00 am |
And suddenly, the post is back.
What’s up with that?
TCO // March 30, 2008 at 2:36 am |
what are you talking a bout?
steven mosher // March 30, 2008 at 2:58 am |
can we get back to the moronic salary discussion
steven mosher // March 30, 2008 at 3:05 am |
At this point I would expect some CA troll to say something like this.
“if Lonnie Thompson doesn’t have to archive his Ice Cores, why should Watts archive his posts”
Those shifty denialists.
Everyone should be like me and Tamino. We admitted our mistakes. The sky didnt fall. In fact we get along better since that. Its Forest Gump simple
dhogaza // March 30, 2008 at 4:47 am |
So you admit that comparing MBH98 to Piltdown Man in it’s “dishonesty” was a mistake?
And while doing so, you dare to suggest that Tamino has made a mistake (ad hom) as insulting, stupid, and undefesible as that?
fred // March 30, 2008 at 6:54 am |
There have been some deeply depressing threads on this blog, but this really takes it to a new low. What everyone needs to do is focus on the central issue in an unemotive way. Ignore troll postings. Keep to the track of threads. Resist the temptation to post wildly on anything under the sun, like salaries. Tamino needs to edit far more ruthlessly.
The bottom line of this is that denialism and hysteria of equal intensity but perhaps different amounts are being found both on both sides of the debate, and are equally inappropriate in both places, and contribute equally little to understanding.
Yes, I know, you immediately think that no, denialism is only found on the other side. That is your problem in a nutshell. Count to ten. Or 100
Tamino can be a great educational resource, whether one agrees with him or not, if only you all would let him be that.
steven mosher // March 30, 2008 at 12:56 pm |
dhog, you keep bring up the Piltdown comment, so I will explain again. The thought came to when I kept reading comments comparing skeptics to holocaust deniers, flat earthers, and creationists. In the context of the latter it occurred to me that the hockey stick was rather like the Piltdown man. So I posted a picture of the Piltdown and he was shown carving a stick. It was too funny. After i made the joke, I commented that the comparison was harsh and that the hockey stick didnt rise to the level of a hoax.
I dont suggest that Tamino has done anything remtely close to this.
steven mosher // March 30, 2008 at 1:19 pm |
everybody makes mistakes.
http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/
this one shows the prob;ems in applying acausal filters to data series
Hank Roberts // March 30, 2008 at 4:16 pm |
Wait, you’re the originator of “Piltdown Mann” as an epithet? Google that, you have some harshness to reel back in.
wattsupwiththat // March 30, 2008 at 7:29 pm |
Tamino wrote: And by the way, when I do original work I *do* put my name to it — in the peer-reviewed literature.
I had no idea you’d published. Congratulations. I would enjoy reading those, Can you provide links or a title for them? Thanks.
[Response: Is that the best you can do? Try yet again to violate my anonymity? On my own blog? You have no shame.
Previously you spoke highly of the value of learning from your mistakes. So I'll ask again what I ask at the end of my post about the work of your friend Basil: what have you learned?]
Lee // March 30, 2008 at 9:03 pm |
I suspect I may know why those posts went down and back up. The remaidner of my comments ahve been scrubbed from them – there were stil soem of my postes remainign in part 1 before they disappeared for a short while. As of now, Anthony Watts has gone and removed every one of my comments from both those threads.
I’m finding this immensely amusing – except that people still take him seriously, as if he had any honesty and knows anything about what he was saying.
P. Lewis // March 30, 2008 at 9:57 pm |
Yes, Lee, but your ghost lingers on because others reference your comments.
wattsupwiththat // March 30, 2008 at 10:35 pm |
Thanks, I appreciate the response.
[Response: I guess you've learned nothing.]
wattsupwiththat // March 30, 2008 at 10:55 pm |
No actually, I’ve learned a tremendous amount.
I think “What I’ve learned” as a subject is a good idea, and I really do appreciate the suggestion.
Thus I’m going to do a summary post about “what I’ve learned” in the last year since I started blogging on the subject.
BTW it was you who brought up your peer reviewed work, I figure if you are proud of it and it is relevant to the climate discussion, that you’d want to share it. That’s all. If your want to keep them secret, that’s fine by me.
Enjoy your remaining weekend. Don’t forget to watch Gore on 60 minutes tonight.
Timothy Chase // March 30, 2008 at 11:35 pm |
wattsupwiththat wrote:
Personally, I’d love to read whatever Tamino has published in whatever field it might be. However, Tamino has received death threats before by people who are convinced that “global warming” is just a con on the part of some vast conspiracy to establish an authoritarian world government. I myself am not entirely sure who deserves more blame — those who make such threats or those who encourage the sorts of delusions that motivate people to make such threats.
Lee // March 31, 2008 at 12:25 am |
Guffaw!
Anthony has me killfiled over there now, it seems. Previously, my posts at “wattsup…” were visible to me with a ‘being moderated’ tag, just like here at Open Mind, until they were approved and everyone could see them, or killed and removed outright. I just made a post over there, asking Anthony why he is removing my posts from 3-4 weeks ago, and – nothing.
I guess he *has* learned something…
Max // March 31, 2008 at 2:35 am |
“Personally, I’d love to read whatever Tamino has published in whatever field it might be. However, Tamino has received death threats before by people who are convinced that “global warming” is just a con on the part of some vast conspiracy to establish an authoritarian world government. I myself am not entirely sure who deserves more blame — those who make such threats or those who encourage the sorts of delusions that motivate people to make such threats.”
If he has published anything of any worth thats supportive of AGW, would he already not be on some kooks hitlist anyway? Let me guess Exxon is hiding on the grass knoll.. Considering whats at stake financially and credibilty wise on either side why are some many errr, skeptics, or as I prefer Natural variability fans using their real names?
Hank Roberts // March 31, 2008 at 4:05 am |
Max, think:
http://pubs.acs.org/subscribe/journals/esthag-w/2006/aug/policy/pt_santer.html
dhogaza // March 31, 2008 at 4:22 am |
Because they’re stupid?
And your implied “we are better than you are” meaning is easily refuted by the fact that real, live, climate scientists publish many papers under their own names.
While leading denialists like McIntyre are mostly reduced to publishing in E&E, or the denialblogosphere (watts).
Timothy Chase // March 31, 2008 at 5:24 am |
Max wrote:
I meant that if he were publishing statistical analysis associated with biometrics or financial derivatives, it would probably be fascinating. As for the kooks, we don’t need them encouraged or manufactured.
*
Max wrote:
According to their well-documented public tax records, Exxon spends only in the neighborhood of 1-2 million a year on the funding of denialist outfits, if I remember correctly. They could undoubtedly spend a bit more than that, but I presume they wouldn’t want the negative publicity. Undoubtedly they wouldn’t want to do anything that would be too high profile — like knock off Al Gore or James Hansen. They have a bit more sense than this.
No — when considering the issue of responsibility for encouraging kooks I was thinking a little further down the foodchain.
*
Max wrote:
Scientists don’t win the Nobel by supporting the status quo but by shattering it — if they can make a good case. But the number of viable alternatives to anthropogenic global warming for explaining warming since the 1970s appear to be — effectively non-existent.
Solar variability — but for the solar cycles — flat to falling since 1951, galactic cosmic rays, no trend, … . And even if you were to somehow come up with an alternative to anthropogenic global warming, some alternate mechanism, you would have to explain why greenhouse gases aren’t having the effect that radiation transfer theory (grounded in quantum mechanics, supported by spectral analysis, imaged by satellites and measured in terms of backradiation) says they must.
Gee — I believe you would deserve several Nobel prizes. And that’s before you turn to the paleoclimate record.
*
Max wrote:
Apparently you haven’t spent much time on the blogs — a fair number of them don’t.
Incidentally, I notice that you didn’t give a last name. Don’t have one? — or did you simply forget it?
Gavin's Pussycat // March 31, 2008 at 7:58 am |
Max:
In my understanding he is an astronomer/astrophysicist. The only relevance to AGW would be that it shows him to be a real, competent scientist with a grasp of data analysis and statistics, not a hack. Precisely because climate is not his job but his spare-time interest, that he uses a nom de plume. His justified concern is more harrassment, of him and his employer, than death threats, fascinating though as those are…
Going after the “skeptics” in a way that makes a difference would be genocide, not homicide ;-)
cthulhu // April 1, 2008 at 1:38 am |
”
everybody makes mistakes.
http://hadobs.metoffice.com/hadcrut3/diagnostics/global/nh+sh/
this one shows the problems in applying acausal filters to data series
”
Over at CA I noticed it is being talked about as if possibily Hadley only spotted the error because it shows a downturn due to a very cool Jan 2008, while they didn’t spot the error when it showed an upturn after a very warm (if not record) Jan 2007.
I have no idea what an acausal filter is, but I do have an idea of why the CRU trendline method was faulty, because it’s possibly the simplest error ever.
The CRU trendline basically treated the average anomoly of the year to date as the anomoly of the year itself. So if it was Feb 1st 2008 and the anomoly for Jan 2008 was 0.3, they treated the entire year 2008 as having an anomoly of 0.3C
Obviously because monthly anomolies fluctuate a lot more than annual anomolies this made the direction of the end of the trendline erratic in the few months of a new year. Januaries really impacted it if they were extreme.
Back in Jan 2007 I vaguely remember the 2007 value being really high on the bar chart. Sure I thought, this is just the anomoly of the year to date, surely the trendline doesn’t treat the Jan 2007 anomoly as representing the entire 2007 year, surely it’s more complex than that. And you see I couldn’t tell, because the trendline was up anyway.
I didn’t notice how flawed this was until the Jan 2008 update when the negative swing really reversed the trendline in a way that was obviously not representative of what a single month (or two) should be able to do.
They changed it in the last few weeks so that the trend doesn’t continue the trend past through the current year.
I suspect Hadley people only noticed it was incorrect when someone like myself spotted the reveral it due to Jan 2008 and informed them.
Mick // August 9, 2008 at 9:08 pm |
The declining trend makes more sense viewed from the 1600s.