Guest post by Lance Wallace
The carbon dioxide data from Mauna Loa is widely recognized to be extremely regular and possibly exponential in nature. If it is exponential, we can learn about when it may have started “taking off” from a constant pre-Industrial Revolution background, and can also predict its future behavior. There may also be information in the residuals—are there any cyclic or other variations that can be related to known climatic oscillations like El Niños?
I am sure others have fitted a model to it, but I thought I would do my own fit. Using the latest NOAA monthly seasonally adjusted CO2 dataset running from March 1958 to May 2012 (646 months) I tried fitting a quadratic and an exponential to the data. The quadratic fit gave a slightly better average error (0.46 ppm compared to 0.57 ppm). On the other hand, the exponential fit gave parameters that have more understandable interpretations. Figures 1 and 2 show the quadratic and exponential fits.
Figure 1. Quadratic fit to Mauna Loa monthly observations.
Figure 2. Exponential fit
From the exponential fit, we see that the “start year” for the exponential was 1958-235 = 1723, and that in and before that year the predicted CO2 level was 260 ppm. These values are not far off the estimated level of 280 ppm up until the Industrial Revolution. It might be noted that Newcomen invented his steam engine in 1712, although the start of the Industrial Revolution is generally considered to be later in the century. The e-folding time (for the incremental CO2 levels > 260 ppm) is 59 years, or a half-life of 59 ln 2 = 41 years.
The model predicts CO2 levels in future years as in Figure 3. The doubling from 260 to 520 ppm occurs in the year 2050.
Figure 3. Model predictions from 1722 to 2050.
The departures from the model are interesting in themselves. The residuals from both the quadratic and exponential fits are shown in Figure 4.
Figure 4. Residuals from the quadratic and exponential fits.
Both fits show similar cyclic behavior, with the CO2 levels higher than predicted from about 1958-62 and also 1978-92. More rapid oscillations with smaller amplitudes occur after 2002. There are sharp peaks in 1973 and 1998 (the latter coinciding with the super El Niño.) Whether the oil crisis of 1973 has anything to do with this I can’t say. For persons who know more than I about decadal oscillations these results may be of interest.
The data were taken from the NOAA site at ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_mm_mlo.txt
The nonlinear fits were done using Excel Solver and placing no restrictions on the 3 parameters in each model.
Allan MacRae says:
June 10, 2012 at 2:44 am
If you know of any urban sites with continuous 24-hour CO2 readings, I would be pleased to see them.
Here is a semi-urban site near Giessen (Linden), where the historical measurements at 3x per day in the period 1939-1941 are one of the main series in Beck’s compilation that caused the 1942 “peak”:
http://www.hlug.de/?id=7122&view=messwerte&detail=graph&station=1005
Where you can download the data.
The historical site was at the Eastern edge of the town of Giessen, largely downwind of the town for the most prevailing wind directions. The new station is at the edge of a small village, more SW of the town.
IF (as it appears from the limited urban atmospheric CO2 data I’ve seen) these humanmade CO2 emission are sequestered locally close to the urban source, they do NOT form part of a large, global quasi-equilibrium of CO2 between vegetation, soil and water.
Of course they do! Every plant has a limited uptake of CO2, depending of sunlight, water, nutritients and CO2 level. Every molecule of human CO2 captured is one less natural molecule captured. Thus while the human CO2 may be captured within a minute of release by the next nearby tree, the capturing doesn’t influence the increase in total CO2 in the atmosphere, which goes up with the total amount released by humans. The same applies for CO2 capturing by oceans.
But at the other side, the total increase in CO2 also increases the uptake by oceans and vegetation, no matter which of the two sources remains in the atmosphere. That makes that in average half of the emissions in quantity remains in the atmosphere, regardless if none of the original human CO2 still resides in the atmosphere and already is replaced by natural CO2 or all human CO2 still is there.
Thank you Ferdinand,
Linden has CO2 data measurements. You say it is semi-urban. June 2012 CO2 rises to a maximum at night and declines during the day – there is no urban signature in the CO2 data.
http://www.hlug.de/?id=7122&view=messwerte&detail=graph&station=1005
Satellite Photo of the Linden Station
http://maps.google.ca/maps?hl=en&pq=gersfeld+rhon+germany&cp=11&gs_id=e&xhr=t&q=wasserkuppe&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1600&bih=754&wrapid=tljp133933845412600&um=1&ie=UTF-8&sa=N&tab=wl
So has Wasserkuppe, which is at 931m elevation in a wilderness area.
http://www.hlug.de/?id=7122&station=801
Satellite Photo of the Wasserkuppe Station
http://maps.google.ca/maps?hl=en&pq=gersfeld+rhon+germany&cp=11&gs_id=e&xhr=t&q=wasserkuppe&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1600&bih=754&wrapid=tljp133933845412600&um=1&ie=UTF-8&sa=N&tab=wl
The other ~30 active atmospheric monitoring stations in Germany do NOT measure CO2. Several are in Frankfurt. Pity.
http://www.hlug.de/?id=7122&station=801
Allan MacRae says:
June 10, 2012 at 8:23 am
The other ~30 active atmospheric monitoring stations in Germany do NOT measure CO2. Several are in Frankfurt. Pity.
The list is from Hessen, only one of the states in Germany.
I knew that Schauninsland in the Black Forest (SW Germany, in another state: Baden-Würtemberg) had long time CO2 measurements, where only 10% were deemed background, due to the high contamination from valley air. While searching for the data, I saw an interesting paper:
http://archiv.ub.uni-heidelberg.de/volltextserver/volltexte/2006/6727/pdf/LevinGRL2003.pdf
They use 14C/12C to determine how much CO2 comes from fossil fuel emissions…
Ferdinand Engelbeen says:
June 8, 2012 at 12:19 pm
Myrrh says:
June 8, 2012 at 4:38 am
Carbon dioxide being one and a half times heavier than air will always spontaneously sink, displacing the lighter air around it, unless work is being done such as wind, heat, and, being heavier than air will not spontaneously rise into the atmosphere.
It will. I don’t know where you live, but here in Europe we frequently see Sahara sand settled on our cars (the same for the West Coast of the US for sand from the Chinese/Mongolian deserts) if the wind is from that direction. That travels thousands of kilometers. Even if it is hundreds times heavier than air or CO2. The difference in specific mass between CO2 and air is only 1.5 times not hundreds, thus once mixed in, it may be transported over hundreds of times longer distances than sand, thus simply all over the world.
“It will” what? Spontaneously sink or not spontaneously rise in air?
I’ll take that you’re objecting to “will not spontaneously rise into the atmosphere” and so you don’t understand what I’ve said because you give an example of wind carrying it, which is not spontaneous, but work.
Which is why their conclusion in the AIRS data included the note to selves that they needed to go and study wind systems, because it’s not always windy and they found CO2 to be lumpy and not at all well-mixed. Spontaneously, because it is heavier than air, carbon dioxide will always sink, displacing air.
Besides “ideal gas spontaneous diffusion in in empty space” and “Brownian motion”, AGWScience Fiction also gives the meme “thoroughly mixed by winds in the turbulent atmosphere” – when these good people educated to fictional fisics memes went off to study wind systems, they would have found immediately that a) it’s not always windy and b) most winds are local and c) local winds and others vary in height and especially, d) that the major wind systems do not cross hemispheres..
Hopefully they also discovered that in their fisics there is no wind – because their atmosphere is made up of ideal gases in empty space, and ideal gases don’t have volume, and wind is volumes of real gas on the move.
Looking out my window now across the garden to the fields to the distant hills, it’s not windy. There’s a slight intermittent gentle breeze around 10-20′, but the tops of the trees higher than this aren’t moving.
Further, CO2 is measured near ground (where it may be pure CO2 or pure air or anything in between), but from about 500 m above land and over the oceans, there is near as much CO2 near the surface as at 4,000 m high as up to 20 km height (measured by satellite, balloons, airplanes)…
Well, that’s far too specific without any detail – show and tell.
According to what you believe, the measurements at Mauna Loa or the South Pole should show far less CO2 values than near ground, which is not the case at all.
Nope, I’ve never said that – I don’t use that expression when discussing any of this ..; “belief” is a word in constant use by AGWSF promoters, not me, because they’re not interested in the facts.
The only cases where CO2 stays (temporarely) near ground is if huge upwelling occurs at once, then the wind or simple convection has not the time to mix that CO2 in. Or in caves where CO2 can build up if more is produced than is removed. Or in ice cores, where the CO2 in the stagnant part of the air/ice column increases with about 1% near the bottom in a period of 40 year, called the “gravitational fractionation” (for which is compensated in the CO2 measurements of the ice bubbles).
Gravity because carbon dioxide is a real gas not ideal, it has weight, because of gravity.
Well there are lots of ongoing local measurements in forests and such which normally have several flasks at different heights and note changes in winds and such and of course changes due to photosynthesis and so on, most plants do this AM and they’ll be breathing out CO2 the rest of the time. Generally the pattern will be less CO2 at the greater heights except windy conditions, which will disperse it lower down.
[Winds, convection currents, will appear locally from temperature differences in local air as the land heats up and the hot volume of air rising becoming less dense, as will in any carbon dioxide in it, and so adjacent cooler volumes being heavier will sink and flow under this – this flowing volume of air is called wind. Inshore/Offshore descriptions are good for getting the picture because the differences in heat capacities of water and land show this phenomenon clearly.]
And don’t forget rain, any rainstorm will take all the CO2 around and bring it to the ground. All of it.
As I said, Keeling never proved there was such a critter as “well-mixed background” – the natural properties of carbon dioxide and the processes in the natural world make this idea nonsense. It’s all local.
And, as I note in a reply from you to Gail, changing tack and talking averages distracting from this is on par with AGWSF giving contradictory reasons for the claimed existence of this elusive “well-mixed background”. There is no internal consistency in AGWSF fisics, just mixing up real world physics – all to the end of “proving” that “well-mixed background ” exists, you cannot separate out the AGWSF meme with its fake fisics explanations from ‘averages’; there is no real world physics that gives “well-mixed background”, as they discovered in AIRS.
Local measurements will always give local conditions and from these averages could be established, that has to include all the varied factors in play particular to each locality which will tell its own story. Keeling didn’t want this, he had an agenda and picked the lowest value he could to create his fraudulent science, and came up specifically with this idea of “well-mixed background”, which he famously said could be measured as well from Mauna Loa as from anywhere else. Which is why we have the steadily rising faux carbon dioxide levels from Keeling et al unrelated to anything happening with temperatures during that time – see Fig 5 on http://www.globalweathercycles.com/GWGCNCF/chapter5.htm
From http://icecap.us/images/uploads/08_Beck-2.pdf
“2. THE CO2 BACKGROUND HYPOTHESIS
Charles Keeling soon noticed a rise of atmospheric carbon dioxide concentration.
From his measurements in the 50s and 60s on the Pacific coast in USA, on Mauna Loa
and the Antarctica, he concluded that he had measured a constant worldwide
background concentration of CO2. The CO2 background should be the CO2
concentration around the world, free from local sources which had increased from 315
ppm in 1958 to 380 ppm in 2008 mainly by burning of fossil fuels.
“According to the IPCC this is the main cause of global climate change [10]
“Keeling also was the first to introduce carbon isotopes (13C) to the investigation of the
carbon cycle and the origin of the carbon source [17]. This lead to the assumption that
CO2 from fossil sources enrich in the atmosphere while natural photosynthesis and animal
respiration compensate each other and can therefore be ignored. Consequently man-made
CO2 was firmly recognized as the polluter of the atmosphere, i.e. the worldwide rise of
the CO2 concentration. In fact CO2 from burning fossil fuels and phytoplankton from the
oceans—which cover the globe to 71%—have about the same 13 C value.”
“1955: The invention of the background level out of 50 samples”
CHARLES D. KEELING “explanation: in the afternoon best mixing if air without plant + soil influence”
BECK: missing [in blue]: check of soil degassing, check of weather (humidity, precipitation..)!!
“Figure 2: C. Keeling’s first attempts to measure the CO2 background concentration
(Keeling 1958) using the lowest CO2 concentration in the afternoon. On the top the
head of the paper by C. Keeling 1958; below the graph of the diurnal variation of
CO2 at the Olympic Forest in the state of Washington. In red additional information
on the measurement conditions and the type of calculation of a daily average C.
Keeling had used. In blue missing measurements to get the right conclusion.
…
Figure 2 shows the birth of the idea of a CO2 background concentration 1955.
At that time C. Keeling had measured CO2 in summer, using a home-made
manometer. He needed about 90 minutes to obtain each value [17]. He conceded in
1993 that he had not read any technical literature [16], so he probably did not know
that by using the existing high precision gas analysers designed by Haldane,
Petterson, Schuftan or Kauko, he could have obtained readings within minutes,
getting a far more accurate value down to 0.33%. This means an accuracy of about
+/-1 ppm using 309 ppm in 1955.
Considering the measured diurnal CO2 variation in the forest we notice a much
higher CO2 content in the air at night than during the day, caused by the absorption of
some of the carbon dioxide by the photosynthesis. The correct average would have
been 365.3 ppm, which is typical for such a location in summer. In fact Keeling used
only the lowest measured values made in the afternoon on the grounds and that there
is a compensation of soil respiration by soil organisms and photosynthesis. Soil respiration produces about the same amount CO2 as the respiration of animals on the ground. But plants do respire too especially at night. Keeling did not measure the soil respiration and the possibility of geological soil degassing by rock weathering remains.
“This procedure of ignoring natural CO2 sources that may make a large contribution to the atmospheric concentration is maintained until today.”
So, we have the well known history of Callendar’s cherry picking and an example here of Keeling’s, one of many, besides showing he was a complete ignoramous in the subject of measuring CO2..
Here’s background to the beginning with Revelle by By John Coleman: http://www.kickthemallout.com/article.php/Video-Revelle_Admits_CO2_Theory_Wrong
Here’s background to the history of CO2 measurements: Historic variations in CO2 measurements
Tony Brown
http://noconsensus.wordpress.com/2010/03/06/historic-variations-in-co2-measurements/
– real scientists who strove to understand the subject and built on each others hard work from honesty in reporting and continual refinement of method. Don’t you bloody dare claim their work or their understanding inferior to Keeling. Keeling may well have pretended later that he knew the Haldane..
See further:
Brownian motion at
http://en.wikipedia.org/wiki/Brownian_motion
Further proof you don’t know what I’m talking about as you’ve confused wind with Brownian motion, not only confusing convection with Brownian motion, but having no sense of scale of these two different processes.
see http://en.wikipedia.org/wiki/Diffusion
“Separation diffusion from convection in gases
While Brownian motion of multi-molecular mesoscopic particles (like pollen grains studied by Brown) is observable under an optical microscope, molecular diffusion can only be probed in carefully controlled experimental conditions. Since Graham experiments, it is well known that avoiding of convection is necessary and this may be a non-trivial task.
“Under normal conditions, molecular diffusion dominates only on length scales between nanometer and millimeter. On larger length scales, transport in liquids and gases is normally due to another transport phenomenon, convection, and to study diffusion on the larger scale, special efforts are needed.
“Therefore, some often cited examples of diffusion are wrong: If cologne is sprayed in one place, it will soon be smelled in the entire room, but a simple calculation shows that this can’t be due to diffusion. Convective motion persists in the room because the temperature inhomogeneity. If ink is dropped in water, one usually observes an inhomogeneous evolution of the spatial distribution, which clearly indicates convection (caused, in particular, by this dropping).”
More garbled processes to create a fictional fisics to promote AGW.
And, that you haven’t even bothered to read it yourself… So, obviously you can’t follow my explanations of how AGWSF mixes up real world physics by cherry picking bits from unrelated processes as well as changing properties..
From your wiki page: “Consider, for instance, particles suspended in a viscous fluid in a gravitational field. Gravity tends to make the particles settle, whereas diffusion acts to homogenize them, driving them into regions of smaller concentration. Under the action of gravity, a particle acquires a downward speed of …, where ..is the mass of the particle, .. is the acceleration due to gravity, and .. is the particle’s mobility in the fluid. ….. In a state of dynamic equilibrium, the particles are distributed according to the barometric distribution.
..
“Dynamic equilibrium is established because the more that particles are pulled down by gravity, the greater is the tendency for the particles to migrate to regions of lower concentration. The flux is given by Fick’s law, [see picture here: 220px-Brownian_motion_gamboge.jpg] “The equilibrium distribution for particles fof gamboge shows the tendency for granules to move to regions of lower concentration when affected by gravity.”
So where’s the “well-mixed background” from Brownian Motion?
According to what you believe, the measurements at Mauna Loa or the South Pole should show far less CO2 values than near ground, which is not the case at all.
So Brownian Motion irrelevant?
FerdiEgb says:
June 8, 2012 at 1:17 pm
Myrrh says:
June 8, 2012 at 12:35 pm
Besides the problems by using unreliable data from heavily contaminated places, Beck’s high CO2 values around 1942 are not confirmed by any other CO2 (or d13C) proxy I know of. Including stomata data, the other posterchild to haunt the ice core data…
Gosh Ferdi, you’re quite a wag, “data unreliable from heavily contaminated places” immediately associated with Beck in the next sentence, when it’s Mauna Loa the poster child of heavily contaminated places – was that deliberate?
Let’s take a good look first at what is being measured, Beck’s hundreds of thousands real data records of well measured and well understood in local conditions against: “Greenhouse Gas Observatories Downwind from Erupting Volcanoes”
http://www.americanthinker.com/2009/12/greenhouse_gas_observatories_d.html
From which:
“In case readers don’t get the point, the NOAA also explains (emphasis in original):
“GLOBALVIEW-CO2 is derived from measurements but contains no actual data. To facilitate use with carbon cycle modeling studies, the measurements have been processed (smoothed, interpolated, and extrapolated) resulting in extended records that are evenly incremented in time.”
“Processed, smoothed, interpolated, and extrapolated? Data extension? Data integration? No actual data? Making atmospheric measurements that will facilitate a predetermined conclusion?”
I would stress “records that are evenly incremented in time” – because that’s exactly what the agenda pre-determined it to be – hence the silly Keeling Curve.
And Willis –
“The Observatory at Point Barrow, Alaska is about 170 miles downwind from the Prudhoe Bay headquarters of the North Slope oil industry. It is therefore subject to a localized increase in man-made air pollution, including CO2 emissions. Coincidentally, of course, the Barrow Observatory was established in 1973 — just before construction began on the Trans-Alaska Pipeline. Barrow is also annually subject to several months of “Arctic haze,” which University of Alaska Geophysicist Ned Rozell indicates is from ex-Soviet and new Chinese “iron, nickel and copper smelters and inefficient coal-burning plants.”
Do please read the rest of that article by Andrew Walden, editor of Hawaii Free Press
As for stomata data, please fetch for the last century, I can’t find anything specific to that period. But I have found that stomata data and South Pole Flask measurements much higher than from ice core records – http://www.geocraft.com/WVFossils/stomata.html
See Fig.5 “Stomata CO2 record is in general agreement with Air Flask CO2 measurements”.
South Pole Air Flask (1957-2006 AD)
Atmospheric CO2 concentrations (ppmv) derived from flask samples collected at South Pole, Antarctica
L.P. Steele, P.B. Krummel, R.L. Langenfelds
Atmospheric, Research, Commonwealth, Scientific, and Industrial Research Organization, Australia
August 2007
(“A precipitous drop in CO2 during the “Younger Dryas” was captured nicely by the stomata reord, but missed by the CO2 record in ice cores.”)
“But the main problem is the speed with which it should have happened. While a few thousands volcanoes all spuwing lots of extra CO2 are remotely possible to give a 80 ppmv increase in only 7 years, there is no sink on this world which can absorb 80 ppmv CO2 within 7 years, if Beck’s CO2 peak was true. If you know of such mechanism, I am very interested…”
Plants absorb more CO2 when there is more CO2 to absorb. They’d have been woofing it as fast as their little stomata could grab it – have you been missing the references throughout the discussions here on WUWT on the optimum levels for plant photosynthesis and better harvests we’re getting and greening deserts? Life gobbled it up.
Gail Combs says:
June 9, 2012 at 8:09 am
The first clue in this snippet is “the measurements were taken with a new infra-red (IR) absorbing instrumental method, never validated versus the accurate wet chemical techniques. “ Now I am not the math wiz that Willis and others are but if there is one thing I am familiar with it is doing quantitative analysis on “a new infra-red (IR) absorbing instrument”
Well, what you needed was Keeling on your team… 🙂
Re your collection on Mauna Loa – I’ve been sitting here thinking how far I’ve come since I first took an interest and was pointed in the direction of Willis’s under and over the volcano, his link above. He’s such a good writer that I got the picture immediately, that he was simply regurgitating what he had been told, because, no question arose from him about the huge amounts of carbon dioxide produced by the world’s premier volcanic hot spot.. Nothing to detract from the “pristine” meme, that downwelling contains nought but the most pure unadulterated thoroughly mixed so it can’t be unmixed without work being done background CO2 levels which arrive naked and unadorned by local production from miles up in the Northeast tradewinds – if he’s not on their payroll he should be.
And reading his description of how they measured, I thought, WUWT? They’re arbitrarily choosing it each time. I checked their own descriptions of this, yes, as you point out, they don’t even hide this! But what they do do is keep calling it “pristine” which I can understand a non-scientist might not notice, but when a non-scientist with an interest like myself can spot the bull piled on bull practically immediately, how come so many of real scientists on the world’s premier science blog, can’t?
The more I investigated the more blown away I was by the shear audacity of the con, but what still amazes me is that even after pointing out lots and lots of piles of bull on bull associated with this Keeling myth of “well-mixed background”, some just refuse to give up the notion that Callendar/Keeling’s low number was deliberately cherry-picked to represent it. All that’s happening with the agenda driven Mauna Loa/Scripts/NOAA data is that they have been gradually, by incremental steps, bringing it to real world figures which haven’t changed from the time when Keeling got in on the act – the 400 ppm was standard industry average then…
Which is what got me interested in exploring all this in the first place, the tweaks to sell a fictional fisics to promote AGW.
We’ve now had a generation educated in it, so as I gave the story of the PhD in physics who told me carbon dioxide was an ideal gas and would spontaneously diffuse into the atmosphere which was empty space and couldn’t become unmixed without a great deal of work being done, a whole generation of scientists in all fields who think this fictional well-mixed background, which Keeling created, actually exists.
So we have the shock horror of the AIRS team who couldn’t understand why it wasn’t well-mixed, lumpy freaked them out because they knew nothing about real gases, they only knew the memes.
As here: NASA Releases New CO2 Data, Refutes Conventional Wisdom
“For carbon dioxide, AIRS measures and tracks its concentration and movement as it moves across the globe. Observation data is critical for scientists to validate their models or adjust them to better predict the impact of greenhouse gas emissions on the weather and climate.
The data have already refuted a long-held belief that carbon dioxide is evenly distributed and do so fairly quickly in the atmosphere once it rises from the ground, said Moustafa Chahine, the science team leader of the AIRS project at the Jet Propulsion Laboratory, at the annual meeting of the American Geophysical Union (AGU) in San Francisco Tuesday.
“Contrary to the prevailing wisdom, carbon dioxide is not well mixed in the mid-troposphere,” Chahine said. “You can see the jet stream splitting the carbon dioxide clump.”
“AIRS data shows instead that carbon dioxide, which has seen its rate of increase accelerating from 1 part per million in 1955 to 2 parts per million today, would require about two to three years before it blends in, he said. The atmosphere currently has about 400 parts per million.”
http://www.greentechmedia.com/articles/read/nasa-releases-new-co2-data-refutes-conventional-wisdom/
Aw shucks, must be millions more parts per million by now with all that accumulating going on, but they’re still using the 19th century figure…
So where’s the “spontaneous diffusion of carbon dioxide as ideal gas which gives the same proportion globally practically immediately like scent wafting from a bottle opened in the classroom, or ink poured into a glass of water, which can’t separate out without a great deal of work being done”?
What? It stays lumpy even when split by the jet stream?
“Conventional wisdom”, “prevailing wisdom” and “a long-held belief” – created by AGWScience Fiction’s meme creating department.
How can anyone still argue the increase from the low figure created by them? We could really do with a collation under the headings of the different memes, as you’ve pulled together “pristine”..
And still, they won’t release the top of the troposphere or bottom of the troposphere…
Re volcanic activity – There’s more on the geologist website fromTimothy Casey:
“2.0 Calculated Estimates: Glorified Guesswork
The estimation of worldwide volcanic CO2 emission is undermined by a severe shortage of data. To make matters worse, the reported output of any individual volcano is itself an estimate based on limited rather than complete measurement. One may reasonably assume that in each case, such estimates are based on a representative and statistically significant quantity of empirical measurements. Then we read statements, such as this one courtesy of the USGS (2010):
“In point of fact, the total worldwide estimate of roughly 55 MtCpa is by one researcher, rather than “scientists” in general. More importantly, this estimate by Gerlach (1991) is based on emission measurements taken from only seven subaerial volcanoes and three hydrothermal vent sites. Yet the USGS glibly claims that Gerlach’s estimate includes both subaerial and submarine volcanoes in roughly equal amounts. Given the more than 3 million volcanoes worldwide indicated by the work of Hillier & Watts (2007), one might be prone to wonder about the statistical significance of Gerlach’s seven subaerial volcanoes and three hydrothermal vent sites. If the statement of the USGS concerning volcanic CO2 is any indication of the reliability of expert consensus, it would seem that verifiable facts are eminently more trustworthy than professional opinion.
“This is not an isolated case. Kerrick ..” continued on http://carbon-budget.geologist-1011.net/
My bold italics.
And there’s this from http://chiefio.wordpress.com/2011/12/10/liquid-co2-on-the-ocean-bottom/
White Smokers & The Lake Of CO2 On The Ocean Bottom
“It is looking to me like we really don’t know a darned thing about the CO2 cycle in the deep oceans. How much, where, what happens, where it comes from, where it goes to, where it makes puddles and lakes.”
..
“The Obvious
To me it’s a pretty obvious question to ask that if we KNOW the volcanic cycle is highly variable (at least on land) and we KNOW that CO2 comes from these volcanic related vents on the ocean floor, and we KNOW that the quantity of CO2 cycled by nature is vastly more than the amount we produce: Why in the heck is anyone not of the opinion that CO2 is largely prone to fluctuations from natural volcanic cycles? How could anyone ever justify asserting the human component matters, even a tiny bit, as it’s going to be well inside the natural variation of these volcanic sources. (There are vastly more volcanoes under the sea than on land. We’re talking powers of ten more…)
When we can see globs of CO2 on the ocean floor with shrimp swimming through the CO2 “smoke” and we can find lakes of the stuff on the ocean floor, how in heck can anyone say a few PPM of gas in the air will ever matter to the ocean? Or the life in it?
When we can find puddles of stuff on the ocean floor, and have literal geysers of the stuff too, how can we ever think that those quantities are not important to how much leaves the ocean and goes into the air?
It looks to me like the ocean is quite comfortable dealing with levels of CO2 flux that make our burning of fossil fuels look like a lit match in a forest fire. As much as it might hurt some folks ego, it looks to me like we just don’t matter.”
Allan MacRae says:
June 10, 2012 at 2:58 am
Gail, the scale in this AIRS animation goes from 364 to 386 ppm CO2. That seems reasonable to me.
______________________________________
It is not the scale I am talking about it is the fact they do averages. That 364 to 386 ppm is not the high and the low readings in the troposphere but the AVERAGE for a large hunk of air over time.
NASA says of AIRS,
Nadir is looking straight down so this is the minimum column of air scanned. I am assuming that the “footprint” represents a column of air 13.5 km thick by [800 km/90 foot prints] or 8.9 km wide.
Another page states AIRS reports the daytime and nighttime global distribution of carbon dioxide in the mid-troposphere at a nadir resolution of 90 km x 90 km. So it looks like the “footprints” above are combined to give ONE reading, and that reading is the AVERAGE of a heck of a lot of air over a 12 hour period!
Another page on AIRS says:
And AIRS is STILL finding variations from foot print to foot print despite all the combining and averaging being done. SEE
http://airs.jpl.nasa.gov/data/about_airs_co2_data/about_airs_co2_data_files/index.jpg of “The monthly average of carbon dioxide in the middle troposphere made with AIRS data retrieved during July 2003
You can hide a lot of information that you do not want people to know by using averages without giving the standard deviation. If the atmosphere is not well mixed then Callender and Keeling had no basis for tossing all the “outliers” from Mauna Loa and the historical data that Beck dug out.
So once you get rid of the theory of “well mixed” and “background CO2” you can not toss out Scholander’s Barrow data ranging from 386 ppm to 500 ppm in 1947 and the whole edifice of CAGW collapses because a reading of 400 ppm of CO2 is nothing to write home about, especially given Kaplan’s Graph of SST vs CO2.
The use of averages is just another way to lie with statistics and that is why I keep pounding on the issue. As tony Brown said “*Averaging disguises the ranges.”
If CO2 was not well-mixed but generally sank to the ground, we’d have trouble breathing at sea level. If molecular weight mattered the gases in the open atmosphere would be seen in different layers, like a cake. But even the gentlest, unfelt breeze, mixes them, like dust motes dancing in a ray of light, even in a sealed room. There is some clumping, small and large-scale, and particularly near source, and all the gases thin out with height, but there is no stratification of gases in the atmopsphere. You can pour out CO2 and it will pool on the ground for a little while, but before long it will be mixed into the rest of the atmosphere. Wind and molecular energy strongly overwhelm gravity for gases in the open atmosphere.
(Various forces work to ‘stratify’ ozone, but it is a heavy gas and should not be hanging around the stratosphere if gravity had much to do with it!)
Gail – I vaguely recall reading this after the AIRS pronounced CO2 lumpy and insignificant in the scheme of things compared to water vapour, although I don’t know if was produced before or after it does read like damage limitation with spin spin spin – no mention of lumpy and Chahine’s shock to “conventional wisdom”, and they’ve got Mauna Loa as an extinct volcano and it makes a virtue of the scant 18 month data gathering before Keeling’s mad pronouncement that he’d found a trend.
http://airs.jpl.nasa.gov/story_archive/Measuring_CO2_from_Space/History_CO2_Measurements/
How many have got the time to deconstruct every statement in it?
How can NASA put this out?
In thinking about it I have a SWAG as to what was going on in the following quote thanks to the information from Tony Brown and Perkin-Elmer
The Mauna Loa Observatory (MLO) was dedicated on 28 June 1956. Perkin-Elmer introduced the first (single beam ) IR in 1954. In 1957 they introduced the “First affordable infrared instrument: Model 137 Infracord, low cost, double beam, optical null” P-E talks of introducing their new Gas Chromatograph, the Model 154-C, at the 1959 Pittsburgh Conference and had a glowing write-up in Analytical Chemistry. I have no doubt that the new IR instrument was also introduced at a conference and had a big write-up in the literature. I am sure Keeling hear of the instrument and given the sales pitch I got from P-E a decade, a glowing pep talk about how this machine could “leap tall buildings…” he took the bait and bought the instrument.
So here is Keeling saddled with a real dog of an instrument on an active volcano with winds blowing from and to the sea. His analytical results must have been all over the map! He can not get the darn thing to give good calibration results against the wet chemistry methods, the site, far from being “pristine” as he thought, could not be worse and he has to make it all good because of the tons of money already poured into the project. So you have Callender, Keeling and Revelle all communicating with each other. Callender has already set the precedence of cherry picking “low background CO2 measurements” Revelle is giving pep talks about how important the research is and so they end-up running with cherry picked values and averaged data because that is all they had given the situation. After all not only is their project, their reputations and grant money at stake but they KNOW they are right and that the research is VERY IMPORTANT.
SO as Tony Brown said The overall effect of taking CO2 measurements at Mauna Loa situated on top of an active volcano at over 3000 m altitude and surrounded by a constantly outgasing warm ocean shall be left to others to debate, but the averaging disguises the considerable daily variability. Of course tossing out the “outliers” that do not “fit the curve” takes care of the rest of the problem.
As I noted in another comment somewhere on WUWT, Many Scientists Fabricate and Falsify Research and once they start they generally have to continue.
For example Diederik Stapel, a prominent Dutch social psychologist, routinely falsified data and made up entire experiments. He falsified at least 30 papers. University of Connecticut found 145 instances over seven years in which Dr. Dipak Das, a heart Doctor, fabricated, falsified and manipulated data.
Once started it is very difficult to extricate yourself from the lies without a career ending blow-up.
barry says:
June 10, 2012 at 6:35 pm
If CO2 was not well-mixed but generally sank to the ground, we’d have trouble breathing at sea level….
_______________________________
Barry, as I mentioned above Lake Nyros (sitting on a volcanic vent) belched CO2 and killed all the animals and 1700 people within a 15-mile (25km) radius of the lake. So yes CO2 can sink to the ground and “flow” Humans can tolerate several 1000 ppm, the threshold in mine-safety regulations is 5000 ppm of carbon dioxide.
I worked for years in chemical batch mix rooms and continuous process which is why I laugh when anyone tries to tell me CO2 is “well mixed” Spend several years sampling batches to find out how long it takes a mechanically mixed batch to be come “well mixed” gives a real life appreciation of how HARD it is to get the &^%$%@* stuff to mix and how long it actually takes. (at least an hour)
Think about CO2:
1. You have Volcanoes spewing CO2 through eruptions and vents
2. You have humans producing CO2
3. You have water dissolving or out gassing CO2 as the surface temperature changes.
4. You have plants gobbling CO2 during the day and respiring it at night.
5. You have termites and swamps producing more CO2 than all humans combined.
And all you have to mix it is Brownian motion, updrafts and winds as the sources and sinks continue to change the local amount of CO2.
As the wheat experiment showed you get a local reading of 300 ppm during the day and as much as a 500 ppm reading at night.
Every watch a planes contrail or the steam from a nuclear cooling tower? The visible moisture can stay for HOURS depending on the weather. and that “clump” of air containing the water vapor stays pretty much clumped. Ever watch clouds… So why in hades do you think water vapor will stay clumped and CO2, just because we can not see, it will not?
Myrrh says:
June 10, 2012 at 4:01 pm
Myrrh, I am glad some one understands what I am trying to say about the “well mixed” fallacy. Without it the entire house of cards falls so I can not see why everyone is defending Keeling and Mauna Loa especially when they come right out and SAY they are cherry picking. (and averaging)
Myrrh says: June 10, 2012 at 1:53 pm
“In fact CO2 from burning fossil fuels and phytoplankton from the oceans—which cover the globe to 71%—have about the same 13 C value”
Interesting, thanks – do you have a source?
Allen,
Google “Metabolic Fractionation of C13 & C12 in Plants” and http://www.ncbi.nlm.nih.gov/pmc/articles/PMC406107/ tops the list.
Gail,
Yes, local variability occurs dependent on various factors, just as clouds form dependent on temperature and pressure etc. But these are incidental to the average (or ‘background’) content. The amount of water vapour is different everywhere, but the atmospheric total is in equilibrium until something distrubs that equilibrium. Same goes for CO2. We have corroborating measurements from all over the world, not just from ML.
Here are the data for a non-urban site in Tasmania (Cape Grim), a location chosen for its isolation, considered one of the best locations to get a ‘pure’ atmospherc composition that reflects the global average.
Here are samples from Ascension Island in the Northern Hemisphere. (Period overlaps with Cape Grim)
Easter Island
Estavan Point, Canada
(I’m picking places that look like they’re non-urban and have some overlap with each other… that’s my sole criteria here, and I’m not omitting anything I find for any other reason)
Kotelny Island
HAKUHO MARU (Japanese research vessel)
Assy Plateau Kazakhstan
You will see the same thing as I do if you go through the records. There is a rise in CO2 background levels worldwide at the same concentration everywhere. There are also daily and seasonal fluctuations, but the background levels are consistent across a range of montoring sites, undertaken by many different groups. One would have to invoke the most far-reaching conspiracy theory to deny such corroboration of the accumulation of atmospheric CO2. You can ignore Keeling and ML – it doesn’t change the facts of world-wide inventories of atmospheric CO2. This is is ‘settled’ science. There are far more worthy candidates for skepticism.
But phytoplankton gives off 14 C. Fossil fuels do not. Therefore, if phytoplankton were a net contributor to global levels, we would see a corresponding rise in C14. We do not.
It is the ratio of 12, 13 and 14 C that establishes the anthro fingerprint of rising CO2. 14 C decays after 50, 000 years. It’s lack of increase in 14 C that tells us ancient carbon is responsible for the rise in atmospheric CO2 in the modern era.
Indeed. O3 and CO2 differ by only about 5% in density; they should be well-mixed with each other, wherever they are!
😉
barry says: June 10, 2012 at 9:29 pm
Thanks Barry. First, I agree with your comments to Gail regarding CO2 measurements, with some limitations.
I have worked with much of the data you cited, and accept that atmospheric CO2 concentration is rising and is pretty much as reported at these sites, NOTWITHSTANDING that the data is intensively cherry-picked to remove outliers, etc. The correlation from site to site and the declining seasonal sawtooth (oscillation) from Barrow Alaska to the South Pole would be extremely difficult to falsify, even if the intent existed to do so (which I doubt). Also, the fact that dCO2/dt varies ~contemporaneously with temperature and CO2 lags temperature by ~9 months would also be difficult to fake. I have verified this relationship with both satellite and surface temperatures, even though there appears to be a significant warming bias in the surface temperatures. I have also verified the relationship using global CO2 and only Mauna Loa CO2 measurements.
I have less faith in the pre-1958 CO2 measurements from ice cores etc. – I think they are directionally correct but may show some absolute drift from actuals.
Nor do I have much faith in the alleged “pre-industrial” level of ~280 ppm CO2 in the atmosphere. This could be completely false, especially since CO2 lags temperature at all measured time scales and past temperatures have certainly been both warmer (MWP) and colder (LIA) than the present.
I just have not done enough work to confirm or deny these numbers, and there is so much BS in climate science (e.g. the Mann hokey stick, Climategate, etc.) that I like to verify everything myself.)
I keep finding more and more evidence that indicates that humanmade CO2 emissions are simply not the primary cause of the increase in atmospheric CO2. In those few sites I have seen where CO2 is measured in the urban environment, the natural CO2 signature prevails and the human signature is typically absent.
___________
barry says:
June 10, 2012 at 9:42 pm
“In fact CO2 from burning fossil fuels and phytoplankton from the oceans—which cover the globe to 71%—have about the same 13 C value”
But phytoplankton gives off 14 C. Fossil fuels do not. Therefore, if phytoplankton were a net contributor to global levels, we would see a corresponding rise in C14. We do not.
It is the ratio of 12, 13 and 14 C that establishes the anthro fingerprint of rising CO2. 14 C decays after 50, 000 years. It’s lack of increase in 14 C that tells us ancient carbon is responsible for the rise in atmospheric CO2 in the modern era.
Thanks Barry. Again, I have not checked this C14/13/12 relationship carefully myself. Those who have keep poking holes in it – the latest being Murry Salby. Do you have any comments on the work of these parties who have slagged the C14/13/12 argument? Are they all wrong? If so where?
Myrrh says:
June 10, 2012 at 2:04 pm
I’ll make it as shor as possiblet…
“It will” what? Spontaneously sink or not spontaneously rise in air?
It will spontaneously mix in air, partly due to diffusion (the practical result of the Brownian motion) and it will be mixed by wind, turbulence and convection to any height and latitude.
It takes 40 years in stagnant air to show a 1% increase in CO2 levels at the bottom of an air column in firn. By far not enough to give any settling out in free air.
See also the CO2 levels taken by airplanes over Colorado:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/inversion_co2.jpg
Besides huge changes in the first 500 meter over land, where huge sources and sinks are at work, the levels hardly change with height.
http://www.globalweathercycles.com/GWGCNCF/chapter5.htm
This reference says that there is no correlation between CO2 and temperature. Gail Combs did give a reference that temperature caused the CO2 rise. Some discrepancy here…
http://www.kickthemallout.com/article.php/Video-Revelle_Admits_CO2_Theory_Wrong
The film is about the link between CO2 and global warming. That is a complete different topic. Where does Revelle say that the CO2 measurements are/were wrong?
http://icecap.us/images/uploads/08_Beck-2.pdf
Again, read what Keeling himself said about the “background” CO2. Not what others say what he did or said or meant or allege what his motives were…
What the late Beck said is the equivalent of measuring temperature on a hot asphalt roof and averaging it over the day, then adding the averaging of a lot of other such places.
Nobody would suggest that that is the best way to establish the average temperature of the earth… But you and others insist that it should be done. Not very consequent…
Further proof you don’t know what I’m talking about as you’ve confused wind with Brownian motion, not only confusing convection with Brownian motion, but having no sense of scale of these two different processes.
Please Myrrh, wind, turbulence and convection does bring CO2 to any height in the atmosphere and Brownian motion / diffusion keeps it in the atmosphere. As proven, it takes 40 years without any convection to increase the CO2 levesl with 1% at the bottom of a 70 meter stagnant air column. That makes that far away from huge sources and sinks, the CO2 levels are within thight borders all over the earth.
Allan,
I’m not up on those arguments, though did read some of Murray Salby a while back. There is a body of work and a great many atmospheric chemists behind the mainstream view. Are they all wrong?
(I’m nowhere near expert enough to answer your questions properly – Ferdinand is the guy for that)
Not too long ago it was popular to say the warming of surface temperature over the last century or so was not settled science, and many observers, includng one or two scientists involved in climate studies, claimed that much or all of the warming was either bad data or urban heat island effect. After BEST and the dedicated work of some skeptics (notably at the Air Vent), regulars here began to adopt the position that of course no one doubts that global temperature has risen, just that… (insert alternative topic). But that fashion changed again – not from any new information (indeed all work on the subject since, by skeptic and other, corroborates), but because that’s what people want to believe, o5r at least, that’s the conversation they’d prefer to see happening.
There are some published scientists that completely deny that there is any greenhouse effect from CO2 (Gerlich and Tscheuschner 2009). They have their supporters, too.
Here is a physicist who has successfully refuted Einstein’s special Theory of Relativity. Here is a page with many links to the debunking of Einstein’s theories (an excellent site). You can find an army of real scientists and dedicated amateurs demolishing once and for all the great hoax of Einsteinism.
My point is, every topic has its critics. That doesn’t necessarily mean that the topic is actually controversial. For obvious reasons, AGW attracts the largest army of detractors. The size of that population is indicative only of the political interest, not the quality of the criticism/s.
I don’t think Salby poked holes in the CO2 theory. IIRC, the implication of his thesis is that a global temperature change of less than 1C may be responsible for an increase of 100ppm CO2, which is preposterous. Global temps changed by ~5C during the last few glacial transitions, which would suggest CO2 swings of 500ppm, effectively giving the atmosphere a negative balance of CO2 during glacial maximum.
Allan, I think that looking at the details of this topic is interesting for various reasons, but it seems to me that some people are a little bit too passionate about finding holes. A dispassionate appraisal doesn’t leave much wiggle room, but a person with a strong agenda will always be able to find some uncertainty to chew over in science. The rise in CO2 is due to us. Some small part of the rise may be from deforestation (max 25%, but that’s still ‘us’), and there is variability from short-term temperature changes (ENSO), local circumstances, and diurnal and seasonal influences, but we emit 30 billion Gt every year (on average), and half that is added to the atmosphere every year (on average). It’s simple arithmetic. The isotopic argument is actually irrelevant, but it corroborates anyway.
Myrrh says:
June 10, 2012 at 2:04 pm
Gosh Ferdi, you’re quite a wag, “data unreliable from heavily contaminated places” immediately associated with Beck in the next sentence, when it’s Mauna Loa the poster child of heavily contaminated places – was that deliberate?
For your interest, the influence of local contamination is easely seen in a huge variability of the measurements within an hour and/or within a day. The standardeviation is the main measure for the variability. The historical measurements at Giessen, one of the cornerstones of Beck’s 1942 “peak” has a standard deviation of 68 ppmv. The average stdev of the hourly averaged raw data at Mauna Loa is 0.2 ppmv (2004). The maximum stdev for any hour in that year is 3.65 ppmv and the stdev over the full year, thus including the CO2 changes over the seasons and the trend, downwind volcanic emissions and upwind, depleted by vegetation air from the valley, is 2.16 ppmv.
You may observe that the 1942 “peak” is within 2 sigma of the measurements at Giessen, thus insignificant and that the trend at Mauna Loa after 2-3 years surpasses the 2 sigma range.
Now you want to convince me that the measurements at Giessen are acceptable, but these at Mauna Loa aren’t…
http://www.americanthinker.com/2009/12/greenhouse_gas_observatories_d.html
Please do some thinking for yourself… again. What the American “thinker” says is pure nonsense. Mount Erebus at 800 miles from the South Pole that may influence the results? Come on, Myrrh. And all these sources (volcanoes, swamps, vegetation, the South Pole base power plant,…) simply follow the global human emissions in an incredible straightforward rate of over 50% in the past 160 years? Of course human emissions simply disappear in space and someone with a big turnwheel regulates the natural emissions in ratio with the human emissions…
The Observatory at Point Barrow, Alaska is about 170 miles downwind from the Prudhoe Bay headquarters of the North Slope oil industry
Again pure nonsense, wind at Point Barrow is mainly from the Arctic Ocean. If the wind is occasionally from land side, it is not used for averages or trends.
As for stomata data, please fetch for the last century, I can’t find anything specific to that period. But I have found that stomata data and South Pole Flask measurements much higher than from ice core records
Here the overlap between ice core data and direct atmospheric measurements:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/law_dome_sp_co2.jpg
Here the calibration curve for stomata data vs. ice cores, firn and direct measurements over the past century:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/stomata.jpg
If there was a real peak of 80 ppmv around 1942, as the late Ernst Beck alleged, then the stomata reading at 310 ppmv would be off scale. But nothing to see there.
Stomata data in the past may give a better overview of the variability, but are unreliable for past absolute levels, as the local/regional offset may change over the centuries.
Plants absorb more CO2 when there is more CO2 to absorb. They’d have been woofing it as fast as their little stomata could grab it
The current increase with some 100 ppmv CO2 causes a total sink rate of about 2 ppmv/year, of which 1/3rd by vegetation and 2/3rd by the (deep) oceans. Plants don’t double their uptake with a CO2 doubling. In average there is a 50% increase in uptake for a 100% increase in CO2 in ideal circumstances, but nature is seldom ideal…
Thus a 80 ppmv peak in 1942 would require some 120 years of increased uptake to return to near “normal” levels…
barry says:
June 10, 2012 at 9:29 pm
Gail,
Think about CO2… all you have to mix it is Brownian motion, updrafts and winds as the sources and sinks continue to change the local amount of CO2.
Yes, local variability occurs dependent on various factors, just as clouds form dependent on temperature and pressure etc. But these are incidental to the average (or ‘background’) content….
____________________________________
It is pretty obvious that what I am trying to get at is going over most peoples heads so here is the explaination of the statistics:
What I am calling AVERAGES = means.
Statistics for individual samples:
Do not forget that rain droplets will absorb CO2 right out of the air forming carbonic acid. Here are some studies on water vapor. You are not going to find such studies on CO2 because of the “Well Mixed” sacred cow. I am not saying the range (σ) in CO2 is huge, I am just saying that the range (σ) is much wider that reported because the σ reported is the σ for the means and not the individuals.
Also the mixing in the atmospher is not all it is touted to be.
Here is a paper on the mixing of water vapour in the atmosphere. Unfortunately it is pay walled:
IMAGE – Fig. 3. Global distribution of CRISTA 2 water vapour mixing ratios (ppmv) at 100 hPa altitude for 10–15 August 1997.
NASA video: http://www.nasa.gov/mov/291251main_L3_H2O_Final_576.mov
NASA still: http://www.nasa.gov/images/content/291249main_vapor_still_226.jpg
Here is AIRS on percipatable H2O content of the atmosphere: IMAGE This is for “Mean clear air water vapor distribution, 500 millibar to top-of-atmosphere.” Again they are looking at the AVERAGE for a column of air. Recent Climatology, Variability, and Trends in Global Surface Humidity: Surface RH has relatively small spatial and interannual variations, with a mean value of 75%–80% over most oceans in all seasons and 70%–80% over most land areas except for deserts and high terrain, where RH is 30%–60%…. Large RH increases (0.5%–2.0% decade−1) occurred over the central and eastern United States, India, and western China,.. Means of course are the result of AVERAGING.
There is absolutely no reason to believe that CO2 mixing in the atmosphere is any better than that of the mixing of water vapor. You can see the east west bands in both gases.
Gail Combs says:
June 10, 2012 at 6:12 pm
So once you get rid of the theory of “well mixed” and “background CO2″ you can not toss out Scholander’s Barrow data ranging from 386 ppm to 500 ppm in 1947
As said before, the accuracy of the method used at Barrow in 1946-1947 was +/- 150 ppmv. The variability is from the method itself and thus doesn’t give us any clue what the real variability in the outside air was of that time.
The modern station at Barrow has a measurement error of +/- 0.2 ppmv and shows a few spikes of 10 ppmv, with a stdev of a few ppmv in the hourly averages, besides a seasonal variation of +/- 6 ppmv. That includes all local, regional and global natural and human sources and sinks:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/co2_trends_brw_2007_2008.jpg
That is for two years, but all hourly averaged data for the period 1973-2011 show the same low variability, besides the seasonal influence:
ftp://ftp.cmdl.noaa.gov/ccg/co2/in-situ/brw/
Thus in my opinion, the historical data from Barrow are only good for vertical classification.
ARGGGGrrrr
The symbol for sigma shows in the reply box but not in the comment. (grumble)
Gail Combs says:
June 11, 2012 at 6:13 am
For comparison:
All modern CO2 stations take 10-second voltage samples during 40 minutes + 20 minutes of calibration with 3 calibration gases. That is transformed into an hourly average CO2 level + standarddeviation of the past hour from the 240 snapshots. Every 25th hour, a fourth out-of-range calibration gas is used to check the performance of the other calibration gases during one hour. Thus on a yearly base, the real number of samples is near 1.5 million, of which the hourly averages + stdev is known. Except for mechanical (and instrumental) failures of course.
There are 10 baseline stations which all work in the same way, besides many others which also work in places with little local contamination, with similar procedures. That presents many millions of data per year from a lot of places, including their variability within an hour.
Compare that to the historical data:
Many were one-shots at places with huge diurnal changes. The longest ever series was at Giessen, Germany, with 3 samples a day, of which one (according to modern measurements) is at extra low CO2 levels due to afternoon CO2 absorption by vegetation and 2 at the flanks of the largest diurnal change in CO2 level. That already gives a bias of 40 ppmv in a summer day. Moreover, a slight change in sampling time influences the bias quite a lot.
The overall stdev of the less than 2000 samples over 1.5 years is 68 ppmv. Nobody knows the real accuracy of the method used (no calibration or interlaboratory tests known), the checking of the reagens, the skill of the people, etc. All we know is the huge variability of the historical (and modern) measurements at Giessen. Which in my opinion is enough to exclude such data from any “global” assesment.
But Giessen is the main base of the 1942 “peak” from the late Ernst Beck, together with another long series from Poonah, India. The latter is even worse: the data gathered were intended to see what the CO2 levels did during vegetation growth (rice, soy,…). The samples were from under, inbetween and over the leaves of the growing plants, from barren ground to harvest. And that should give an idea of “global” CO2 levels of that time?