Guest Post by Willis Eschenbach
In 2006, I lived for a year in Waimea, on the Big Island of Hawaii. From my house I could see the Mauna Loa Observatory (MLO). This observatory is the home of the longest continuous series of CO2 measurements we have. The recording station was set up by Dave Keeling in 1959, and has operated continuously ever since.
Figure 1. Mauna Loa Observatory ( 19.536337°N, 155.576248°W)
Here’s a view of the observatory:
Every time the subject of CO2 measurements comes up, people raise all kinds of objections to the Mauna Loa measurements. So I thought I’d start a thread where we can discuss those objections, and perhaps dispose of some of them.
Here are the objections that I hear the most:
1. The Mauna Loa results don’t measure the background CO2 levels.
2. You can’t get accurate CO2 measurements from samples taken on the side of an active volcano that is outgassing CO2.
3. The measurements from Mauna Loa are not representative of the rest of the world.
4. What about the Beck data, doesn’t it contradict the MLO data?
5. Keeling chose a bad location.
Before we get into those issues, let’s start by looking at the local meteorological conditions at the site. Mauna Loa is at an elevation of 3397 metres (11,140 ft) on the side of a 4,170 metre (13,680 ft) volcano way out in the middle of the Pacific Ocean. Because it is on an island, it gets the “sea breeze” in the daytime, and the “land breeze” in the nighttime.
These winds are caused by the differential heating of the land and the sea. Land heats up much faster than the ocean. So during the day, the warmer land heats the air, which rises. This rising air is replaced by air moving in from the surrounding ocean, creating the “sea breeze”.
At night, the situation is reversed. The land is cooler than the ocean. This cools the air. The cool air runs downhill along the slopes of the island and out to sea, creating the “land breeze”. Here’s a drawing of the situation:
Figure 2. Day and night breezes at Mauna Loa.
Now that we understand what is happening at Mauna Loa, let’s look at the objections.
1. The Mauna Loa results don’t measure the background CO2 levels. As you might imagine from Fig. 2, the CO2 measurements are taken only at night. Thus, they are measuring descending air that is coming from thousands of feet aloft. This air has traveled across half of the Pacific Ocean, so it is far from any man-made CO2 sources. And as a result, it is very representative of the global background CO2 levels. That’s why Keeling chose the site.
2. You can’t get accurate CO2 measurements from samples taken on the side of an active volcano that is outgassing CO2. This seems like an insuperable objection. I mean, Mauna Loa is in fact an active volcano that is outgassing CO2. How do they avoid that?
The answer lies in the fact that the volcanic gasses are very rich in CO2. At night, they are trapped in a thin layer near the ground by a temperature inversion.
To detect the difference between volcanic and background CO2, the measurements are taken simultaneously from tall towers and from near the ground, at intervals throughout the night. Background CO2 levels will be around 380 ppmv (these days), will be steady, and will be identical at the top and bottom of the towers. Volcanic gasses, on the other hand, will be well above 380 ppmv, will be variable, and will be greater near the ground than at the top of the towers.
This allows the scientists to distinguish reliably between volcanic and background CO2 levels. Here is a description of the process:
Air samples at Mauna Loa are collected continuously from air intakes at the top of four 7-m towers and one 27-m tower. Four air samples are collected each hour for the purpose of determining the CO2 concentration. Determinations of CO2 are made by using a Siemens Ultramat 3 nondispersive infrared gas analyzer with a water vapor freeze trap. This analyzer registers the concentration of CO2 in a stream of air flowing at ~0.5 L/min. Every 30 minutes, the flow is replaced by a stream of calibrating gas or “working reference gas”. In December 1983, CO2-in-N2 calibration gases were replaced with the currently used CO2-in-air calibration gases. These calibration gases and other reference gases are compared periodically to determine the instrument sensitivity and to check for possible contamination in the air-handling system. These reference gases are themselves calibrated against specific standard gases whose CO2 concentrations are determined manometrically. Greater details about the sampling methods at Mauna Loa are given in Keeling et al. (1982) and Keeling et al. (2002).
Hourly averages of atmospheric CO2 concentration, wind speed, and wind direction are plotted as a basis for selecting data for further processing. Data are selected for periods of steady hourly data to within ~0.5 parts per million by volume (ppmv); at least six consecutive hours of steady data are required to form a daily average. Greater details about the data selection criteria used at Mauna Loa are given in Bacastow et al. (1985). Data are in terms of the Scripps “03A” calibration scale.
There is a more detailed description of the measurement and selection process here.
As a result, the Mauna Loa record does accurately measure the background CO2 levels, despite the fact that it is on an active volcano. The samples that are identified as volcanic CO2 are not thrown away, however. They are used for analyses of the volcanic emission rates, such as this one (pdf).
3. The measurements from Mauna Loa are not representative of the rest of the world. Well, yes and no. The concentration of atmospheric CO2 varies by month, and also by latitude. Here is a “carpet diagram” of the changes by time and latitude.
Figure 3. A “carpet diagram” of CO2 distributions, by time and latitude.
Note that the swings are much greater in the Northern Hemisphere. Presumably, this is from the plants in the much larger land area of the Northern Hemisphere. However, the difference between the annual average of the Northern and Southern Hemispheres is small. In addition, there are smaller daily variations around the planet. An animation of these is visible here, with day by day variations available here.
Figure 4 shows is a typical day’s variations, picked at random:
Figure 4. Snapshot of the variations in tropospheric CO2. Note that the range is small, about ±1% of the average value.
In general, the different global records match quite closely. In addition to the Mauna Loa observatory, NOAA maintains CO2 measuring stations at Barrow, Alaska; American Samoa; and the South Pole. Here is a comparison of the four records (along with two methane records):
Figure 5. Comparison of the CO2 records from the four NOAA measuring sites.
As you can see, there is very little difference between the CO2 measurements at the four stations – two in the Northern Hemisphere, two in the Southern, two tropical, and two polar.
4. What about the Beck data, doesn’t it contradict the MLO data? In 2007, Ernst-Georg Beck published a paper called “180 Years Of Atmospheric CO2 Gas Analysis by Chemical Methods” (pdf). In it, he showed a variety of results from earlier analyses of the atmospheric CO2. In general, these were larger than either the ice core or the MLO data. So why don’t I believe them?
I do believe them … with a caveat. I think that the Beck data is accurate, but that it is not measuring the background CO2. CO2 measurements need to be done very carefully, in selected locations, to avoid contamination from a host of natural CO2 sources. These sources include industry, automobiles, fires, soil, plants, the list is long. To illustrate the problems, I have graphed the Beck data from his Figure 13, against the Law Dome ice core data and the MLO data.
Figure 6. CO2 data from a variety of sources. White crosses are MLO data. Three separate ice core records are shown. Photo is of Mauna Loa dusted with snow (yes, it snows in Hawaii.) PHOTO SOURCE
There are several things to note about this graph. First, there is good agreement between the Law Dome ice core data and the MLO data over the ~ two decade overlap. Second, there is good agreement between the three separate Law Dome ice core datasets. Third, both the ice cores and the MLO data do not vary much from year to year.
Now look at the various datasets cited by Beck. Many of them vary quite widely from one year to the next. The different datasets show very different values for either the same year or for nearby years. And they differ greatly from both the ice core and the MLO data.
Because of this, I conclude that the Beck data, while valuable for showing ground level CO2 variations at individual locations, do not reflect the background CO2 level of the planet. As such, they cannot be compared to the MLO data, to the ice core data, or to each other.
5. Keeling chose a bad location. I would say that Keeling picked a very good location. It not only allows us to measure the background CO2 in a very accurate manner, it provides invaluable information about the amount of CO2 coming from the volcano.
My conclusion? Most of the records in the field of climate science are short, spotty, and not very accurate. We have little global historical information on ocean temperatures, on land temperatures, on relative humidity, on atmospheric temperatures, on hurricane occurrence and strength, or on a host of other variables. By contrast, the Mauna Loa CO2 records are complete since 1959, are very accurate, and are verified by measurements in several other locations.
I’m about as skeptical as anyone I know. But I think that the Mauna Loa CO2 measurements are arguably the best dataset in the field of climate science. I wouldn’t waste time fighting to disprove them, there are lots of other datasets that deserve closer scrutiny.
[UPDATE] A reader below has added another question, viz:
6. What about Jaworoski’s claim that the ice core data has had its age “adjusted”?
Jaworoski argues that the age of the air in the ice cores has been “adjusted” to make it align with the modern data. He says, for example, that the Siple ice core data has been moved forwards exactly 83 years to make them match the Mauna Loa data.
Dating the ice core data is problematic. We can date the ice itself pretty accurately, through counting layers (like tree rings) and through studying various substances such as volcanic dust that is trapped in the ice. However, dating the air is harder.
The difficulty is that the air is not trapped in the ice immediately. The pores in the “firn”, the snow that falls annually on top of the ice are open. Air can flow in and out.
As more and more snow falls over the years, at some point the pores close off and the air is trapped. So how long does it take for the pores in the firn to seal off?
Unfortunately, as in so many areas of climate science, the answer is … “depends”. It depends inter alia on how much snow falls every year, how much of that snow sublimates (changes from a solid to a gas) every year, and even the shape and size of the individual snowflakes.
The end result of all of this is that we end up with two ages for any given thin slice of an ice core. These are the “ice age” (how old the ice itself is), and the “air age” (how old the air trapped in the ice is). The ice is always older than the air.
The main variable in that is thought to be the annual snowfall. Unfortunately, while we know the current rate of annual snowfall, we don’t know the historical rate, particularly tens of thousands of years ago. So we use the concentration of an isotope of oxygen called “d18O” to estimate the historical snowfall rate, and thence the firn closing rate, and from that the air age.
Sounds a bit sketchy? Well … it is, particularly as we go way back. However, for recent data, it is much more accurate.
So to bring this back to real data, in the ice core data I showed in Fig. 5, the air is calculated to be 30 years younger than the ice for cores DEO8 and DEO8-2, and 58 years younger for the DSS core. Is this correct? I don’t know, but I do know that there are sound scientific reasons for the “adjustment” that Jaworowski objects to .
Finally, the existence of a thirty to sixty year difference in air and ice age doesn’t make much difference in the pre-industrial levels of CO2. This is because prior to about 1800, the level is basically flat, so an error in the air age dating doesn’t change the CO2 values in any significant manner.
FURTHER INFORMATION:
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JER0ME says:(June 5, 2010 at 1:17 am)
“Just a minor point. From my misspent (or I feel very well spent, but others differ) youth on tropical beaches, the breeze tends to go out until midday and then inland until some time in the night”
That is why, generally speaking, surfing is better in the morning when offshore breezes create a better wave face and help stand the wave up longer.
Willis,
I do not understand why there has not been a major increase in the readings since the turn of the new century. A friend in Alsaka complained of the major smog problem in recent years from the increased industrialization of China. Alaska is further away from China than Mauna Loa Observatory so why are we not seeing an up tick in the readings?
The Nasa CO2 maps show the distribution is not uniform.
“Chahine said previous AIRS research data have led to some key findings about mid-tropospheric carbon dioxide. For example, the data have shown that, contrary to prior assumptions, carbon dioxide is not well mixed in the troposphere, but is rather “lumpy.” Until now, models of carbon dioxide transport have assumed its distribution was uniform. “ http://www.jpl.nasa.gov/news/news.cfm?release=2009-196
I also notice that the 2005 image on this page shows a higher concentration over the Mauna Loa area (right edge)
http://www.nasa.gov/images/content/411791main_slide5-AIRS-full.jpg
Map of the Pacific ocean with Trenches and fracture zones.
http://www.freeworldmaps.net/ocean/pacific/index.html
Given how “lumpy” the CO2 readings are, I do not think throwing out Beck’s information and cherry picking low results is justified, nor do I think the ice core measurements can be taken as “gospel”
Very informative. I guess the question that strikes me after reading this is:
What precisely is a “background CO2” level? What exactly does that mean? I think Keeling’s uniform and seasonally varying data itself tells us that there is indeed an area to be found where CO2 levels are quite stable – a background. I would also say based on all the machinations needed to find this stable area of “background level CO2” that a lot of the atmosphere has CO2 that is not extremely well mixed. Is it thought as a general proposition that the upper atmosphere is well mixed and uniform while the lower atmosphere is not? Also, if CO2 is nonuniform in large portions of the atmosphere would that nonuniformity need to be somehow reflected and characterized in a good weather or climate model for it to accurately predict weather or climate?
I seem to remember Arrhenius stating that CO2 concentrations are lower over oceans because it is absorbed there.
On a related note, The Resilient Earth, has a new article discussing the guesswork involved in determining CO² emissions:
http://theresilientearth.com/?q=content/guessing-co2-emissions
My questions:
1. The greening of the planet is well known in the satellite record and thus can be calculated in terms of its potential for CO2 uptake (the deserts are very poor at this while the greened up areas are very good at it – so guess where the CO2 is wafting about?). This same greening can also be linked to a modeled increase in “green eating” populations, which in turn would increase modeled predatory animals who eat the green eating population. Has the greening of the planet been taken into account? The final number related to the %CO2 increase or decrease as a part of the atmosphere needs to be a calculated “modeled” number in the end. I have been trying to find a reference to that paper that suggested, based on such a calculation, that the anthropogenic % contribution has not increased relative to the overall increase in CO2 as a result of the greening up of the planet.
2. MLO has good data. As do the other three stations. I have no dispute with that. What we need to do is cover the planet with sensors placed exactly where CO2 is not. Measuring out-gassing is only half the data we need. It would be like trying to measure area with only the height and not the width. The AIMS website seems to be less than what it was touted to be. There are other satellite based measuring projects going on. What do they say and can we get that in English instead of Japanese?
3. If you are saying that a lot of CO2 is trapped at ground level (it is heavy and inversions do a great job of trapping heavy gasses near the surface) how can it work as a re-emitter of LW radiation? Doesn’t it have to be up in the air, like way up in the air, to do that? So what we really need is a measure of how much CO2 is up in the air and ignore the stuff on the ground.
Richard S Courtney says:
June 5, 2010 at 3:13 am
“…..CO2 is released by the Mauna Loa and the adjacent Kilauea volcanoes. According to your Fig. 2, this volcanic CO2 is
(a) driven aloft by the sea breeze by day, and
(b) driven back down by the land breeze at night.
Hence, it is a gross and improbable assumption that these volcanic emissions do not significantly affect the measurement results because “the CO2 measurements are taken only at night”. And the assumption is especially implausible when there is a slight wind in the direction from Kilauea towards Mauna Loa.
You attempt to overcome this objection by saying:
“To detect the difference between volcanic and background CO2, the measurements are taken simultaneously from tall towers and from near the ground, at intervals throughout the night. Background CO2 levels will be around 380 ppmv (these days), will be steady, and will be identical at the top and bottom of the towers. Volcanic gasses, on the other hand, will be well above 380 ppmv, will be variable, and will be greater near the ground than at the top of the towers.”
Sorry, but I do not buy that. Indeed, false confidence is provided by the comparison of the measurements of the sampled air and the measurements obtained at the towers. The air coming down at night contains CO2 carried aloft during the previous day, but this CO2 is diluted by its spatial spread over the time of its rise and fall. No such dilution can occur to the air at the bottom of the towers. Hence, I disagree with you when you say:
“This allows the scientists to distinguish reliably between volcanic and background CO2 levels.”
“Reliably” ?! No chance!”
________________________________________________________________________
Thank you for that explanation. I do not buy the “reliablity” of this data either. I have spent too much time in chemistry labs to EVER take the information as as gospel especially when there is a lot of money involved and unconscious prejudice.
Thank you Willis!
See also Ferdinand Engelbeen’s debunking of Ernst Beck:
http://www.ferdinand-engelbeen.be/klimaat/beck_data.html
http://www.ferdinand-engelbeen.be/klimaat/co2_measurements.html
Great post, Willis. It certainly does clear up some of the CO2 background level confusion. But it’s not the final word on the entire CO2 emission science story….check this out to see what scientists are now saying about actual CO2 emissions:
http://www.c3headlines.com/2010/06/new-paper-with-stunning-admission-by-climate-alarmist-scientists-actual-co2-emissions-are-unknown-pl.html
So, to further my thoughts, if outgassed volcanic CO2 is subtracted from the equation (because it sinks and shouldn’t be taken into account), will the exhaust from my rig (whose exhaust pipe is only Jeep high off the ground) also be subtracted? Or do we have, in essence, a bigoted response to CO2 on the ground that is from my rig versus CO2 on the ground that is coming from a volcano?
I can’t understand how they got those year-by-year figures from Law Dome. They’re to good to be true. The air in the snow is an open system until the snow is compressed into ice and the air bubbles are closed off. That happens at a depth of about 90 meters. Even in a very wet climate (which Antarctica hasn’t) it takes decades to accumulate that much snow. There is simply no way to get CO2 data representative of short periods from glaciers.
I have three problems with the Mauna Loa data:
1. I have read that something like 80% of the CO2 measurements made at Mauna Loa are routinely discarded because they don’t agree closely enough with the expected results. Is this true?
2. How the heck do they justify retroactively changing published historical CO2 “measurements”? The published CO2 data are highly-processed data either derived from, or cherry-picked to conform to, a series of (I think 4) sinusoids (they pick the frequencies and phases). If they were publishing the results of actual objective measurements, rather than processed data picked to conform to a model, it would be impossible to change history. Anthony published some posts on this a few years ago.
3. When equipment is down, they have been known to interpolate published results, in spite of having samples of air in sealed in bottles to analyze. Interpolation is not measurement.
If these points are true, then Mauna Loa is not publishing objective data. Smells like “post-normal” science to me!
Great work, Willis. It’s important to celebrate the good science being done in the field at the same time as debunking the sloppy stuff.
Mauna Loa shows an annual ‘downtick’ in CO2, falling at its greatest rate between July and August. The explanation that this corresponds to the NH growing season makes good sense. As we know, there is a steady year-on-year rise which we often see explained by the burning of fossil fuels although I wonder if ‘outgassing’ is a feasible alternative explanation (CO2 being a consequence of rising temperatures in recent decades rather than a cause).
It is possible to fit an exponential decay curve to the summer declines. This gives a useful perspective on the ecosystem’s net rate of absorbtion. (I am not advocating a geoengineering project to wheel-clamp the Earth in summer position, by the way.) The summer decline in CO2 PPM, I calculate, shows a half-life of 125 months. The same exercise based on the early years of the Mauna Loa record (late 1950s) gives a similar half-life: 121 months. (In 1958, summer decline from 316PPM at a rate of 1.8PPM/mth; in 2008 summer decline from 386PPM at a rate of 2.15PPM/mth.)
I’m afraid that my maths doesn’t stretch far enough to do the really interesting calculation: residence time, or how long a newly-released CO2 molecule resides in the atmosphere before being reabsorbed or reacted. But if a half-life of 123 +/- 2 months is in the right area, the Royal Society’s claim must be wrong: their website quotes a residence time of over a thousand years. They do not justify this bold quantified statement; I wonder if they would make public the calculations behind it.
First, there is good agreement between the Laws Dome ice core data and the MLO data over the ~ two decade overlap.
A couple posters above mention Zbigniew Jaworowski’s critique. I echo their sentiments. It’s a major outstanding question for me. What say you?
Willis,
I agree with you that the Scripps CO2 data is probably the most accurate measure of background levels. I would go further to say most accurate measure of natural background levels. You base your conclusion on the continuous data monthly averages. I have analyzed the raw flask data that goes back to May of 1957 at the Southpole. In their early learning days, they measured a lot of spikes that exceeded those reported by Beck. These were flagged and not included in monthly averages. At Muana Loa, they were taking samples at different times of day. Much of the nighttime data were flagged because it was too high. Many nights there is not enough wind to keep the air well mixed and CO2 tends to settle near the ground. They eventually routinely took samples at around 10 in the morning.
I have statistically produced a global model of natural background levels from all the Scripps raw flask data that I believe can be used to extrapolate concentrations in the past as well as the future. It is probably our best indicator of climate change but it is a lagging indicator and not a cause. If you would like to compare it to your map for continuous data, you can find my e-mail address at my website (http://www.kidswincom.net) and I can send you a spreadsheet containing the model.
Kilauea just passed the 10,000 day of its current eruption.
The southernmost bakery in the US is located nearby at Naalehu. Great place to stop on your volcano visit.
http://www.bakeshophawaii.com/
Keeling was a first rate scientist, and I thank Willis for his detailed description of the CO2 measurement process, and especially the references contained. Keeling was a U of I [BS chemistry] and Northwestern graduate [PhD in chemistry] , a very careful experimentalist. The use of reference calibration gasses and switching the flows is a very time honored technique in analytical chemistry.
The data is validated in many ways. One could only hope that the temperature records were on such solid footing.
-Jay
Hi Willis,
Having been through this argument several times on different threads, I have concluded that it may be impossible to make progress on this subject with many who comment; they seem immune to influence by data or reasoned analysis. There are so many legitimate scientific issues in the CAGW story which are ripe targets for skeptics that it is difficult for me to understand why some insist on spending time arguing about the cause for increasing atmospheric CO2, when it is one of the very few issues which is pretty much rock solid from a scientific POV. I note that even those climate scientists who are very skeptical of CAGW all agree that emission of CO2 from combustion of fossil fuels is the principle cause for rising atmospheric CO2.
But I do admire your energy in addressing this subject yet again, so I will add a couple of (hopefully) helpful comments.
1. To those who object to the concept of “background” CO2 levels as meaningless: The only CO2 concentration that matters in terms of radiative forcing is the concentration high in the atmosphere. CO2 concentration near sea level makes no difference, since the lower atmosphere is essentially opaque to infrared at the wavelength where CO2 absorbs. The concentration of CO2 matters several Km up and higher, where water vapor is concentration is low and the ~14 micron absorption band of CO2 makes a significant difference in infrared emission to space. So yes, levels of CO2 near the surface can vary a lot (due to a multitude of causes), and CO2 doesn’t influence energy flow near the surface much anyway But the Mauna Loa record (and several other monitoring station records) accurately represents the CO2 concentration high in the atmosphere where the CO2 concentration does matter. Air samples collected by airplanes (~10 Km) have CO2 levels very close to the Mauna Loa values.
2. To those who suggest that a warming ocean has caused much (or all) the rise in CO2: The ocean surface warming that has taken place has been modest (well under 1C over the past 120 years), and that warming has been mostly limited to the top ~200 meters of ocean. Deep ocean water (which represents >95% of the total) has not warmed by more than a tiny fraction of a degree, if at all, and very little of it has been in contact with the atmosphere for many hundreds of years, so could not have out-gassed CO2 even if it had warmed. The amount of CO2 that can out-gas from 200 meters of ocean water due to a 1C rise in temperature is quite small compared to what is in the atmosphere. Comparison of year to year changes in average ocean surface temperature to the trend in CO2 shows a clear influence of ocean surface temperature on CO2 (about +3.5 PPM per degree warming, -3.5 PPM per degree cooling); El Nino (on average, a warmer ocean) causes a faster annual rise in CO2, La Nina (a cooler ocean) causes a slower rise.
So yes, if the entire ocean were to warm many degrees, and if you were willing to wait thousands of years for ocean turn-over to allow equilibration with the atmosphere, then the ocean could contribute a lot of CO2 to the atmosphere. But this has not happened and is not going to happen any time soon.
It seems like such a waste of effort to measure CO2. What is the advantage? Does it give scientists a chance to make wrong but expensive climate predictions?
My recommendation is to measure albedo much more thoroughly and accurately.
To heck with measuring CO2.
Another quick calculation that can be done on the Mauna Loa data is to subtract each year’s average from the preceding to get the inter year change. One finds that the yearly change can vary extensively, for example over a short time span the year to year rate of increase can vary from 0.4 to almost 3
ppm/year (1992 and 1998 for example).
Since the fossil fuel burning of humans is increasing for the last 40 years, certainly not varying by a factor of 6, this wide variation shows that the CO2 increase in the atmosphere is due to more than just man’s combustion.
By the way, Mauna Loa is an “exeprimental” CRN site. It violates several CRN standards, but was placed there in part to sample such environments, it’s likely to not have major changes in terms of urban development, it’s easy to maintain, and its at a site that collects other important data that may be useful in future research by either group.
See http://wattsupwiththat.com/2008/05/14/ftp-access-for-climate-reference-network-data/
http://www.ncdc.noaa.gov/crn/station.htm?stationId=1187
The CRN (Climate Reference Network) makes a wealth of minimally processed data available. I don’t know if they keep the rawest data, e.g. the temperature data from each of three sensors recorded every 10 seconds, but they certainly keep the 5 minute running averages. Raw enough, I should hope.
They may not record wind direction, but they do have accurate wind speed data.
The wind direction would be nice to show the upslope/downslope diurnal changes, but it looks like the wind is fast enough so it’s usually the prevailing winds.
Wunderground may have some sites good for that I found http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=MPKAH1 but it may not be a good site.
I agree with the idea that the Beck data has variation or variability, but it also shows significant trends up and down over time during three periods, two in the 1800s and one in the 1940s.
I find it ingenuous to believe that CO2 has been consistently historically low until now. That’s just not how the real world works. Considering the CO2 in the oceans and the fact that the oceans warm up and cool down, one would expect atmospheric CO2 to fluctuate. To be told that it does not, until man came along, is highly suspicious and probably wrong.
I, thus, disagree with point 4. as Jaworowski has described that the traumatic conditions of extraction of cores and the widespread microfracturing and depressurization could easily cause a 30-50% loss of CO2. Using a 40% average error and back calculating, you end up with values right in the modern day range or even higher. Another study of the ice core data using another approach agrees with this (I apologize for not having the reference handy.).
As our planet has been at a relative low concentration of CO2 in recent years—perilously low from the point of view of plants—it is hard to believe that having it remain low would be any good for anybody or thing. It is only our hubris/naiveness that allows us to think that everything should remain as it was the first time we noticed it.
Also, I have to seriously disagree with Fig. 5 comparing core, volcano, and Beck data as you appear to accept the artificial overlap of the core and volcano data that was performed to make them overlap. Has any one brought up this very questionable “trick” to make CO2 appear to have been historically low? I would guess this is critical as without the shifting the core data indicates a rise earlier than the volcano data, which would agree somewhat with the ups and downs that Beck detected.
It should also be pointed out that we really do not know how much CO2 we emit, the values thrown around are speculations, and that it is a relatively small amount. To assume any rise in CO2 is due to us is also total speculation. We simply cannot say these things with any confidence.
So how come when I plot planetary consumption of fossil fuels (Carbon Dioxide Information Center numbers as proxy – oops – better make sure this doesn’t become “value-added” data) against recorded ML yearly averages, I don’t see any corresponding decreases in the upward CO2 trends to match decreased fuel consumption between 1973 – 76 and 1978 – 86? If man were having this much of an impact on atmospheric CO2, surely these decreases would show up in the ML record? They don’t appear, so we have no influence on atmospheric CO2 levels. Period.
I have a little chart that I would like to include, but don’t have the time to figure out how to put it into this box (or maybe AW won’t allow pictures in the responses).
Also, I never see any discussion on critters in the snow (invertebrates, algae) and the impact they have on CO2 levels in ice cores? Perhaps this is an “inconvenient truth” that needs to be discussed.
I will go with Beck over ice cores any day. The chemical measurements were direct, the accuracy and precision are known, the methods were recorded, and having worked as a plant physiologist measuring atmospheric and soil CO2, I have little belief in the idea of “background” CO2 levels that the CAGW keeps promulgating (AIRS backs me up on this).
Willis,
Thanks for the overview. I wish the all AGW skeptics had such a rational and reasoned approach, just as I wish all AGW “warmists” knew their science better…
The Beck paper makes clear that the CO2 hockey stick that coincides so conveniently with the Mann hockey stick is the product of similar selective use of data, not in the upturned ‘blade,’ but in straightening the handle.
Where Mann straightened the handle by overweighting the insensitive-to-temperature Graybill tree-ring data, the Callendar and Keeling work that the IPCC relies upon simply labelled old studies “inaccurate,” and threw out those that didn’t fit the template.
Beck’s re-examination of the Callendar and Keeling studies finds serious shortcomings. Inclusion of the excised data puts lumps and bumps in the handle that not only don’t correlate with the temperature record, but question the consensus view (which I hold) that the current CO2 rise must be man-made. Net-net, it’s another chink in the fundamental underpinnings of the AGW movement.
OT but can anyone confirm please:
The Arctic ice cap will have to lose roughly 55.000 square KM per day over the next 90 days to the average minimum extent of 5.5/6.0 million square KM, is this rough calculation correct or not?
I wonder what the daily ice loss has been since the ice maximum?
Thanks
Cassie K.