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Author Topic: What is the meaning of 400 ppm (0.04%) atmospheric CO2?  (Read 66478 times)

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #125 on: 28/06/2013 07:59:02 »
Quote
Namely, in a period of warming the differential between zero and [90] latitude causes more clouds at higher latitude and somewhat less at lower latitudes. In a period of cooling, such as now, the differential temp. increases, causing more clouds and rain at lower latitudes and less clouds and rain at higher latitudes.

Possibly the first time I've seen a sensible assessment of cloud effects from anyone else,  in any discussion on climate change!

The effect of water on atmospheric temperature is essentially nonlinear (self-amplifying) which can account for the rapid rise  during warming periods, and is bounded and damped by cloud formation - hence the slow downward drift from a fairly consistent maximum over previous geological cycles. Then since the balance  between carbon dioxide uptake by plants and its emission by cold-blooded animals depends on temperature, it is not surprising that the CO2 graph lags behind the temperature graph where the two are derived from independent proxies, as in ice cores.

The effect of longitude is more subtle than Henry's presumption. Temperature in the British Isles, for instance, is determined principally by the vagaries of the Gulf Stream and the jet stream. Most of the time these islands are covered in cloud and our weather is whatever the advected Atlantic depression gives us, with very little influence from the local greenhouse effect or insolation (it's quite often warmer at night than during the day). But around 30% of the time we have clear, dry  arctic skies, under which the temperature is governed by radiative transfer (hot days, cold nights) as there is very little wind to transfer heat laterally on clear days. Eastern Europe at the same latitude does not get warm, wet, Atlantic air, and the climate is principally driven by radiative transfer and local convection of water.  In short, maritime climate on the west coast of anywhere is determined by events further west, whilst continental climate is dominated by local physics.   
« Last Edit: 28/06/2013 10:58:01 by alancalverd »
 

Online Bored chemist

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #126 on: 28/06/2013 12:45:14 »
And, for the third time now.
The data I was talking about for the past 30 years are here
http://www.skepticalscience.com/pics/RFC12_Fig1.jpg
Can you explain why you need to measure that change of about half a degree to the nearest 0.01 degree?


I'm asking because, if there isn't a good reason, then it looks like you are seeking to set an unnecessarily difficult target of measurement before you accept that there's any warming.


Seriously, do you really think you need a hundred years of measurements that are good to 0.01C to measure a change that seems to be occurring at about 1.5 degrees over that time?

« Last Edit: 28/06/2013 12:49:24 by Bored chemist »
 

Offline MoreCarbonOK

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #127 on: 28/06/2013 13:13:48 »
alan
it is not surprising that the CO2 graph lags behind
henry@alan
forget about CO2. It is not a factor at all. Not in warming and not in the weather.
Look again carefully at the results in my 3 tables.
1)
Note the ratio maxima-means-minima is 6:2:1
(if you take it over the longest period)
If increased CO2 or H2O were a factor, we should see minima rising, pushing up the average.
That is not happening.
2)
If you know how to do curve fitting in excel, you should try and set out the speed of warming/cooling
in K/year,  against time, on each of the 4 final results (on the bottom) for maxima, means and minima.
That gives you K/year 2
Tell me what correlation you get, especially if you try binomials?
3)
note the differences between NH and SH
Does it not seem that most of the (maxima) heat ends up in the SH oceans and is taken by weather and currents up to the NH (means)?

Once you figured out why we see these results happening, you are on your way....!!
You cannot miss it.


« Last Edit: 28/06/2013 13:23:16 by MoreCarbonOK »
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #128 on: 28/06/2013 15:10:38 »
BC: Nice graph, but no title! The temperature of what? Measured how? Calculated how?

If I measure outside air temperature at my local airport over 24 hours, a 15C range is within normal bounds. The automatic system reports every 20 minutes, but if I use 4-hourly manual measurements I'm likely to miss the max (usually around 1300) and min (about 0300). If I take a true 24 hour mean, it will vary between +5 and -5 over four typical consecutive winter days, and anything less than a 2 week average (two Atlantic depressions or one winter high, say) is pretty meaningless.

The reason for asking these nitpicking questions is due to the apparent finesse of the graph. It shows about 18 - 20 ripples per quinquennium, suggesting 3-monthly means. OK, so let's look at "1992.5", halfway between 1990 and 1995. The slope suggests that midsummer was colder than the winter either side, which does not correspond with my recollection.

Or if the abscissal marks indicate mid-year, look at 1995, where once again it apparently got hotter towards the end of the year!   

There's a significant discrepancy between the pink and the red line. Which indicates the truth, and which the opinion of the author?

For what it's worth, the last calibrated meterorological thermometer I owned was scaled in 0.05 degree increments but had mid-range (10 - 30 C) corrections of as much as 0.2 degrees. You simply cannot use these instruments "out of the box" to compare temperatures at different times or places. Problem is that as far as as aviators are concerned, absolute accuracy of +/- 1 degree is of no consequence: we just want to know if we can take off with a reasonable margin of safety, or land without encountering fog or ice, so the kit is generally used without reference to the cal chart and most met reports are actually pretty crude compared with the rate of climate change.

A good rule of thumb in metrology, if not meteorology, is to use an instrument at least one order of magnitude more accurate than the effect you are trying to measure, hence my suggestion of +/- 0.01 deg as the acceptable specification for examining climate change, and for the figures to be meaningful you need to average each location over a year.

There certainly is climate change, always has been and always will be, but I object to a temporary correlation being used as an excuse to raise taxes and screw my life up by politicians jumping on a fatuous bandwaggon.
« Last Edit: 28/06/2013 16:09:01 by alancalverd »
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #129 on: 28/06/2013 16:05:20 »
MCOK: I'll believe your arithmetic. What are the answers? I don't have time to fit the curves myself!
 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #130 on: 28/06/2013 18:21:16 »
Let's face it, the important thing about graphs of global temperature is that they look more like this
/ than like this\
And you don't need a thermometer which reads to 0.01C to spot a change of 0.5 do you.
It doesn't matter where it's measured or by whom as long as it's consistent so ,yes if you measure the temperature every 4 hours you will miss the max and min- but, if you are consistent, you will always miss it by the same extent. And you would have missed it just as much in 1980 as today.

As I have said a number of times you don't need brilliant measurement precision to show a trend.

"A good rule of thumb in metrology, if not meteorology, is to use an instrument at least one order of magnitude more accurate than the effect you are trying to measure, hence my suggestion of +/- 0.01 deg as the acceptable specification for examining climate change, and for the figures to be meaningful you need to average each location over a year. "
Yes, but what said was "you need to be able to measure absolute temperature to better than 0.01 degree over a range of -30 to +40 degrees, for about 100 years."

Over that time the predicted change is about 1.5 degrees so 0.1C would be good enough,  and that's still not allowing for the benefits of averaging many thermometers but you wanted 0.01 degrees.
 

Offline JP

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #131 on: 28/06/2013 18:29:47 »
A good rule of thumb in metrology, if not meteorology, is to use an instrument at least one order of magnitude more accurate than the effect you are trying to measure, hence my suggestion of +/- 0.01 deg as the acceptable specification for examining climate change, and for the figures to be meaningful you need to average each location over a year.

True, and that's why day-to-day measurements of local temperature don't tell us much about climate.  What matters is the uncertainty around the measurements over time, accounting for the law of large numbers, which tells us that combining many measurements actually decreases the uncertainty in the mean relative to the uncertainty in any individual measurement.  If many independent measurements are taken at roughly the same time, then the uncertainty decreased by a factor of ~ the square root of the number of measurements taken. 

I'd go so far as to say that any claims about climate change without an analysis of uncertainties are suspect, because you don't know if they show a trend or just measurement error.  Fortunately, most scientific publications which track temperatures do have error bars, e.g. http://data.giss.nasa.gov/gistemp/2008/  The important part is not that the trendline increase, but that it increases so much relative to measurement uncertainty that we can be nearly certain that the rise is real, and not due to uncertainties in the measurement.

Edit: BC beat me to most of this, but the TL;DR version is that uncertainties can be reduced by averaging and a proper analysis shows global temps increasing.
« Last Edit: 28/06/2013 18:41:28 by JP »
 

Offline MoreCarbonOK

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #132 on: 28/06/2013 19:35:03 »
henry@alan
r2> 0.95
in the case of maxima,
r2=0.996

ergo:
must be natural, such a trend cannot be man made.
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #133 on: 28/06/2013 19:57:51 »
Quote
Let's face it, the important thing about graphs of global temperature.....It doesn't matter where it's measured or by whom

It makes an enormous difference! Just staying with airfields for a moment, in the period of your graph Stansted grew from a small strip of tarmac surrounded by grass and a few huts, to a hundred acres of concrete surrounded by steel hangars, whilst the runway at Wrexham was broken up and removed. Every two minutes, someone dissipates several megajoules of exhaust heat or kinetic energy on the Stansted runway, but you can't land at Wrexham any more. So the local temperature at Stansted went / and that at Wrexham went \  Of course nobody measures the temperature at Wrexham now the runway has been sold as hardcore, so the apparent mean of all British airfields is // !

Pretty obviously, most of our weather data comes from populated areas because that's where the present and forecast conditions are most immediately important, but nearly all of our climate depends on conditions in unpopulated areas like the middle of the Pacific, Arctic, Gobi, northern Canada... which account for 95% of the earth's surface.The problem is that the 5% on which we live is increasingly concreted over and heated by our activities as well as the sun, so the data is both overrepresented and unrepresentative.

So the questions remain: what data is represented by your graph, and why does it show that some winters are warmer than the adjacent summers?
« Last Edit: 28/06/2013 20:02:06 by alancalverd »
 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #134 on: 29/06/2013 11:34:29 »
Not sure why you are so hung up on airfields since we have data like this
http://data.giss.nasa.gov/gistemp/2008/
 but...
How fortunate then that, as I have said repeatedly, the average (which would include Stansted and Wrexham) would give a better result than either of them.
 

Offline MoreCarbonOK

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #135 on: 29/06/2013 15:26:31 »
 JP says
Fortunately, most scientific publications which track temperatures do have error bars, e.g. http://data.giss.nasa.gov/gistemp/2008/  The important part is not that the trendline increase, but that it increases so much relative to measurement uncertainty that we can be nearly certain that the rise is real, and not due to uncertainties in the measurement.

Henry says
sorry JP, but I do not see any error bars in that graph that you quoted?

In fact, subsequent to satisfying my curiosity about error, I did a comparison of same gistemp data set with the wood for trees temperature index, which is an average of anamolies of all available data sets,
here is the result of my analysis
http://www.woodfortrees.org/plot/wti/plot/gistemp/from:1930/to:2014/plot/gistemp/from:1930/to:1980/trend/plot/gistemp/from:1980/to:2002/trend/plot/gistemp/from:2002/to:2014/trend/plot/wti/from:2002/to:2014/trend/plot/wti/from:1980/to:2002/trend

It appears that gis temp. anomalies  are considerably higher than that of other data sets,

which points to a considerable,  apparently consistent, error in the gis temp. data set.


 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #136 on: 29/06/2013 20:29:07 »
Interesting set of graphs.
It illustrates my point nicely.
Even though there's a lot a scatter and different biasses on the two data sets, they both show the same trend.
The data on the right hand side are higher than those on the left- i.e. they show that the world is warming (with some scatter).

 

Offline MoreCarbonOK

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #137 on: 29/06/2013 21:02:41 »
bored chemist says
the two data sets, they both show the same trend.

henry says
true
both show that temps have been gradually going up from 1930 -2000
but going down from 2002
exactly as predicted by me here
http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures
(note there is a lag between energy-in /maxima and energy-out /means)

consequently, seeing that I was right, correctly predicting history, 
unfortunately we will continue cooling down until around 2040

clearly

we cannot trust the data before 1930 as we do not have a global baseline before that time,
because of inaccuracy and different methods of recording means
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #138 on: 29/06/2013 21:17:50 »
Not sure why you are so hung up on airfields since we have data like this
http://data.giss.nasa.gov/gistemp/2008/
 but...
How fortunate then that, as I have said repeatedly, the average (which would include Stansted and Wrexham) would give a better result than either of them.


I'm not "hung up" on airfields, it just happens that nearly all the credible historic data comes from them.

Not sure what you mean by a "better" result. If the average temperature over the entire UK had decreased during the period when Stansted airport was expanding, in what respect would today's Stansted temperature (there is no mean because Wrexham no longer has a runway so it no longer reports temperature) be "better"?

The GISS "data" is fascinating. It goes back to 1880, when one continent (Antarctica) was completely unexplored, another (Australia)  had no established meteorological service, and there were no regular reports from anywhere in the Pacific. So how did they deduce a global mean? I smell bullshit!

So I repeat my question: you showed a graph earlier (reply 126). Where did the data come from and what do the curves represent? Simple enough, surely, to deserve an answer?
 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #139 on: 29/06/2013 21:38:35 »
"Where did the data come from"
Here
http://www.skepticalscience.com/
you can tell from the web address.
But take your pick. There are plenty of web pages out there with data and they seem to show a pretty much consistent rise over the last 30 years or so.
Here's another (chosen pretty much at random from heaps on google).
http://metaclimate.org/2010/02/14/a-ghcn-analysis/

Perhaps you can find the ones where an estimate of the global temperature over that period (rather than cherry picking since the last el nino) actually falls.
Its fair to say that if you look at the results from a google search for images of climate change graphs
there are a lot more like  this / than like this\ and it's hard to see how they could all be wrong.
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #140 on: 30/06/2013 00:19:50 »
It's quite clear where the "skeptical" graph came from, but I'm interested to know what its authors actually plotted. Data that suggests that some winters are warmer than their adjacent summers deserves serious investigation.

The "metaclimate" graph does at least state a geographical area. Amazingly, it includes data from the North Pole in 1880, at least 30 years before anyone actually got there, and probably 90 years before anyone measured temperatures above 80 deg latitude for an entire year.

Skeptic? Moi? No, just wondering how much "climate data" has been falsified, and why it was done in such a transparently amateurish manner..
« Last Edit: 30/06/2013 00:24:41 by alancalverd »
 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #141 on: 30/06/2013 09:18:34 »
"Amazingly, it includes data from the North Pole in 1880"
No, it doesn't and, of course, nor does it pretend to.
Here's the graph's title
"Here’s one of his graphs, covering 70 – 90 deg north latitude"

And here's where that data is explicitly stated to be from
"stations north of 70N latitude — instead of defining separate grid boxes for stations north of 80N latitude, I’ll lump them together with the stations north of 70N latitude."
So the graph is the combination of all the data North of 70 degrees.
That data may be a bit sparse, but that's not the same as saying it's impossible.
Such a comment might be thought of has having " been falsified" in "transparently amateurish manner"

No, I don't think you are a sceptic. A sceptic would look at the data to see what it says, rather than launching a strawman attack on what it doesn't say.

 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #142 on: 30/06/2013 22:47:14 »
The underlying problem is that the world is not a smooth, stationary, homogeneous surface. The air above it moves to transport heat, and clouds form and disperse in different ways at different points. This makes it impossible to generate a sufficient sample from which to extract a meaningful mean, if substantial areas are not mapped - you have to survey the entire surface with a constant finesse, and ensure that your data points are not in any way "special" or time variant. Hence historic temperature observations, which in the main are necessarily "special" and time variant, are not useful in a discussion of trends in global heat exchange or climate.

Fortunately we do have recent satellite data, which can give us good random samples of constant finesse over the entire surface . On the downside there have been significant recalibrations of that data (who ever said physics was easy?) but generally we can accept that satellite data from say 1990 onwards is consistent and representative.

I approve of your definition of a sceptic. So I looked at the "skeptical science" graph and it clearly says that some winters were warmer than the adjacent summers, so once again I ask what is the source data for this interesting graph? It's the counterintuitive that makes life interesting.   
 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #143 on: 01/07/2013 06:44:29 »
Since Summer and Winter are local events, it's easy to see how they might get messed up if you took a global average: do you mean Australia's Summer or England's?
Also, if I wan't to know if the temperature in, for example, London, is changing over time, I clearly don't need to measure the temperature in Antarctica.
All I need are a series of measurements in London.
If those are going up then London is warming.
There are plenty of such measurements going back into history and, if we don't assume that those doing the measuring were incompetent, then we can track the local temperature changes for many places.
In fact, they are generally rising..
As I have said, if you put a forth blaknet on the bed and you get warmer, it's hard to rule out cause and effect.
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #144 on: 01/07/2013 10:22:21 »
I have no idea what the "skeptical science" graph represented - it was your suggestion, and you still haven't told us! However if it represents a true global average, you wouldn't expect to see any seasonal cycles, and if it represents one or other hemisphere, or even one point on the globe, you'd expect the cycles to be consistent. But it showed significant, inconsistent cycles, which makes it very interesting.

The temperature in London is indeed changing with time, because the surface albedo, the concentration of human activity, and the nature of that activity, are all tending to increase the outdoor temperature. But the question we are trying to answer is about the global effect of increasing CO2, not the local effect of urban heat islands, which even the most ardent warmists agree are anomalous. Interestingly, I think the highest local concentration of CO2 in London was probably in the 1940's and 50's when everything was coal fired - and it was a lot colder than recently!

The "fourth blanket" is an interesting analogy. As you add more blankets, so the incremental effect of each becomes smaller. It's called "close" in clothing design, and "saturation" in infrared spectroscopy. If you add a sheet of paper to a continuously changing heap of blankets, you'd be hard put to pin down its causality from observation. And if,  as in the geo-historic CO2 case, the additional blanket always arrived after the temperature had risen and departed after the temperature had fallen, you might question which was the cause and which the effect.

Causality demands correlation, consistent sequencing, and the elimination of co-causation. Until you have demonstrated all three, you can't use a presumption of causality to predict anything qualitatively. And if you want to make a quantitative prediction, you need a good handle on the effects of nonlinearity and saturation. Unfortunately, all the evidence I have seen to date points strongly to temperature being the cause of CO2, not the other way around, so it's difficult to answer the original question.
« Last Edit: 01/07/2013 12:17:52 by alancalverd »
 

Offline JP

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #145 on: 01/07/2013 15:03:18 »
This reminds me of an interesting book I just picked up: The Norm Chronicles by Michael Blastland.  It's about our perceptions of risks vs. the actual statistics.  There's a nice section on climate science which points out that it's virtually impossible to convince die-hards on either side, and this thread backs that up.  His argument is (and he cites a bunch of psychological studies to back this up) that people generally choose a side due to their politics, and since climate science can't be 100% proven either way, they entrench their opinion with whatever ideas they understand, be those scientific or not.  It's interesting that on a science site like this, any post on climate change brings out a lot of people arguing against the scientific consensus, and that virtually all of their arguments don't use anything approaching a scientific methodology.  This strongly argues for better scientific literacy among the voting public (at least among those of us who think policy decisions should be based on sound science.)

Most of the arguments here against climate change are "not even wrong" as Wolfgang Pauli famously put it.  Sure, many are technically true, but they don't have much to do with the scientific method and aren't useful in evaluating climate science one way or the other.  As I've pointed out in a prior thread (and no one bothered to address), the scientific method of climate change involves two major steps:
1) Collecting and analyzing data on climate (primarily temperature).  This means collecting data from modern satellites, historical temperature readings with thermometers, ice cores and so on.  Some of these data sources are more accurate than others, which is where analysis comes in.  We've had a few centuries to perfect our methods of statistical analysis, and so scientists can estimate both mean temperatures (over regions or the whole globe) as well as the uncertainties of those mean estimates.  Arguments against temperature records in this thread ignore those uncertainties.  Sure, the plot of means might or might not be true, but it's important to look at the ranges within which we are 95%, 99%, 99.99999%, etc. that the true mean temperatures lie.  In the end, it's how confident we are of the trend that matters.

2) The second step is coming up with a model that explains and predicts the data.  It's easy to come up with a best fit curve through some section of data and claim that temperature is falling.  It's also just as easy to pick some section of data which shows a massive upward trend and predict we'll all bake to death in a few decades.  What's important is to come up with a model (not just a best fit curve) that makes predictions based on some underlying science (such as the physics/chemistry of CO2), which matches the data.  What do we mean by matching the data?  Again, you have to take a scientific perspective which has been woefully lacking in this thread.  You can compute what are called confidence intervals which tell you that if this model is correct, the data will lie in this range with X% certainty.  Based on that, you can't tell if a model is correct, but you can tell if it's consistent with the data.  You can even say how certain you are that the model is wrong--so if enough data falls outside of the 95% confidence interval, for example, you can throw out the model.

Since this is a science forum, we should be evaluating criteria on these bases, not on the basis of nitpicking details and ignoring the extensive body of literature analyzing both data and models.  Nitpicking details while accounting for 1) and 2) is very useful however, so I look forward to seeing Alan and Henry post some details about how their points correlate with the confidence intervals on the models or uncertainties in measured data. 
 

Offline alancalverd

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #146 on: 01/07/2013 15:48:33 »
Nothing to do with me, JP, but when someone publishes an untitled graph which contains counterintuitive data, I'd like to know what it represents and why it behaves that way. Is that nitpicking or just asking the sort of question that we professional scientists are paid to ask?

Politics? I'm a dyed-in-the-wool atheist leftie tree-hugger. But that derives from studying the data, not the other way around.

A model based on the nonlinear greenhouse effect of water goes a long way to explaining the Vostok ice core data over periods of thousands of years, and recent Mauna Loa data clearly shows the consistent lag of CO2 behind temperature, but the inherently chaotic nature of the planetary atmosphere makes short-term prediction a very risky business.

My preference is always for clean, raw data. Hence Mauna Loa, which represents a "good site" with no obvious CO2 anomalies or heat island effects, and Vostok, which has used the same data collection process for millions of years, are more likely to yield understanding of the process of climate change than any attempt at meta-analysis of incoherent data and proxies.

History has shown that we should be wary of "scientific consensus". Phlogiston, the geocentric universe, the aether, the flat earth, aristotelian gravitation....all held sway as consensus at some time. Early on in our careers, we learn that data is more important. To paraphrase Einstein, when confronted by a debunking consensus paper signed by 100 Nazi professors: "If I had been wrong, one student would have been sufficient." So let's look at the data, please. 

Regarding uncertainties and sampling intervals, here are some samples of a set, each with negligible uncertainty

1, 16, 23, 45, 48, 49, 51, 60, 74, -5, -7, -23, -60, -80 

What is the mean? Well it's about 13.7. But these numbers are "samples" of latitude, reported with something approaching the frequency of, say, air temperature reports. Most meteorologists live in the northern bit of the planet, hence the preponderance of numbers around 40 to 50,  and we have a few reliable reporters from the polar regions. But the mean of these samples tells us nothing about the mean latitude of the planet, which is of course 0.  Same problem with terrestrial-based temperature records: however precise they may be, they only tell us about the temperature in places where people live, and even if we correct for heat island effects, the mean is globally meaningless. You can only determine global trends by evenly sampling 100% of the surface (which was not possible before the 1970s) or smoothing the curve of an unequivocal proxy at one fixed point.   
« Last Edit: 01/07/2013 18:32:44 by alancalverd »
 

Offline MoreCarbonOK

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #147 on: 01/07/2013 17:25:42 »
JP says
that people generally choose a side due to their politics,
Henry says
well...in my case it is actually religion, which demands that I speak the truth at all times,
I determined no influence of the CO2
it is rather natural forces, that show decline in temps. from 2002
as proven to you from all available data sets
and that this decline in temps. will continue
as shown to you from my own data set (with data from 1974-2012)

but I am intrigued to know as to why you did not respond to my question to you raised in my earlier post, specifically addressed to you?
(which seems to confirm some kind of bias from you which I have noted before)

rgrds
H
 

Offline JP

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #148 on: 01/07/2013 18:16:41 »
but I am intrigued to know as to why you did not respond to my question to you raised in my earlier post, specifically addressed to you?
(which seems to confirm some kind of bias from you which I have noted before)

I'd be surprised if you hadn't noted my bias.  In fact, I flat out told you before that I was done debating you on the topic since you use your posts to promote your own model based on cherry-picked data and a best fit curve.  This is a science forum, so I'm biased towards having science-based discussions.   I also don't like repeating myself like a broken record.  Either you don't understand the scientific method, or you're deliberately trolling us.  In either case, since you've made over 100 posts now without making an effort to make your ideas scientific, I don't see why engaging you would be helpful to either of us or to the forum.
 

Offline MoreCarbonOK

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #149 on: 01/07/2013 18:33:13 »
jp says
...to promote your own model based on cherry-picked data and a best fit curve.
henry says
I told you from the beginning that my sample of 47 stations was random,
except for the fact of the choice of stations with complete or nearly complete records...
even choosing more stations won't change the result
if you get a correlation coefficient of 0.997 on the binomial for the drop of maximum temps.....
Either way, even if you believe I am trolling, the question to you was about the error bars,
on the gistemp data set,
which you state were there
but they were not...
 

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Re: What is the meaning of 400 ppm (0.04%) atmospheric CO2?
« Reply #149 on: 01/07/2013 18:33:13 »

 

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