The Quite Unknown Story of CO2 Measurements--in the 1820s

Back then, atmospheric CO2 stood at approx. 410 ppm, if 19th-century literature omitted from Wikipedia and NASA JPL's 'brief history' is taken into consideration--what gives?

Yesterday, I pointed you to some ‘old news’ from 2011 when it was still possible to criticise the reigning (imposed) orthodoxy about ‘climate change’:

CO2-Driven 'Global Warming' is 'Propaganda'

Today’s posting is more of a footnote to yesterday’s piece, but I do think it’s an illustrative one (but I freely admit its rather antiquarian characteristics).

Lost Encyclopaedic Knowledge

‘The Enlightenment’ is conventionally considered the proximate origin of what in today’s terms is called ‘Wikipedia’, that is, compilations of the most important snippets of knowledge for wide distribution.

Diderot’s and d’Alembert’s Encyclopédie (1751-66; check out the partial English version hosted by the U of Chicago) is perhaps the best-known example, even though it is not the first ‘modern’ one.

As some readers may recollect, I hail from German-speaking Central Europe and since I’m a historian of that region’s early modern and modern history, I feel the urge to point you to Zedler’s Großes Universal-Lexicon (lit. Great Complete Encyclopedia, pub. 1731-54) whose compilation began two decades before Diderot’s and d’Alembert’s undertaking.

Still, the prize for the first ‘modern’ encyclopaedia—i.e., one that uses cross-references—goes to one Ephraim Chambers whose Cyclopaedia appeared in print as early as 1728.

All of these—and many other, comparable works—went through multiple editions and, speaking professionally for a moment, are an incredible source for then-common knowledge.

Moreover, in today’s terms, its true heir is Wikipedia. Irrespective of its many flaws—and, as far as I am concerned, the editing of ‘problematic’ entries simply occurs in as close to something approximating ‘real time’, but this does not mean that earlier encyclopaedias were without comparable problems—it is a truly astounding achievement (that, truth be told, also did most printed encyclopaedias in).

One last preliminary remark about the editing processes: what goes into such entries has always been contested knowledge, in particular as editorial oversight is the key component of a kind of ‘guardian’ of what is deemed acceptable. Mind you, this does not mean ‘censorship’, but, truth be told, what goes into entries in printed material is—and always has been—as contested and hotly debated as, say, heavily edited and/or spuriously censored entries in Wikipedia (typically, try anything related to ‘Palestine’).

With these preliminaries out of the way, let’s move on.

From a Somewhat Obscure Swiss Scholar…

Today, I would like to introduce you to one of these encyclopaedic compendia of great importance for German-language Europe: Meyer’s Konversations-Lexicon, which, according to Wikipedia,

was a major encyclopedia in the German language that existed in various editions, and by several titles, from 1839 to 1984, when it merged with the Brockhaus Enzyklopädie.

As an aside, the Brockhaus Enzyklopädie was the German standard reference work, running through 21 print editions before, in 2009, it was moved completely online. In terms of its socio-cultural impact, it was as close to standard inventory of bourgeois households since the 19th century. But I digress.

Have you ever heard of one Nicolas Théodore de Saussure?

If not, let me take you down a particular rabbit-hole.

Born in Geneva in 1767, he was chemist specialising in plant physiology and a pioneer in the study of photosynthesis. He was a Fellow of the Royal Society of London and a Member of the Bavarian Academy of Sciences and Humanities (both in 1820) and a professor at the University of Geneva. He died in Geneva, Switzerland, in 1845 (check out more about his life over at Wikipedia).

Why would I bring up Mr. Saussure in what is technically a follow-up article to yesterday’s piece on ‘global warming’? Well, here goes:

…to CO2 Measurements in the 19th Century

As is well-known, the ‘modern’ era of measuring the CO2 content in the Earth’s atmosphere begins with Charles David Keeling’s (1928-2005) establishment of a way to measure the amount of carbon dioxide. His legacy, the so-called Keeling Curve, documents the growth of atmospheric CO2 concentrations since 1958. According to the latest available measurements (as of 3 July 2023), atmospheric carbon dioxide stands at 422.88 ppm, as taken at Mauna Loa on Big Island, Hawaii.

Do check out the Keeling Curve link and the various graphs shown, as well as a video of ‘how scientists measure carbon dioxide’.

Surfing the dedicated website, one gets the impression that there were no CO2 measurements before the late 1950s, even though there are illustrations that show reconstructions of historic atmospheric carbon dioxide concentrations going back as far as 800K years.

Curiously enough, the 1st edition of Meyer’s Großes Konversations-Lexicon, which appeared between 1857-61, contains an interesting entry about the Earth’s atmosphere. In vol. 2 (Armuth-Bayern), on pp. 320-21 (digitised facsimile), we learn (my translation and with my emphases):

Between 1827 and 1829, Nicolas de Saussure conducted no less than 225 attempts to measure atmospheric carbon dioxide concentrations in the vicinity of Geneva. As these results are the most precise measurements undertaken so far, its results shall be listed in the following [line break added]

In the village of Chambésy [north of Geneva]…on a dry, spacious meadow with loam soil some 16m above Lake Geneva [i.e., about 388m above sea level], the average carbon dioxide levels of the air deriving from 104 measurements taken 4 feet above the ground and at all day- and night-times = 4.15 [units per unit of] vol. per 10,000 [units per unit of] vol. air. Max. = 5.74, min. = 3.15. Separation of daytime from nighttime measurements revealed that carbon dioxide levels are lower during the day than at night. Daytime mean = 3.38, max. = 5.4, min. 3.15; nighttime mean = 4.32, max. = 5.74, min. = 3.21. Furthermore, around noon, [carbon dioxide] concentration was observed to be lower when the wind was not blowing strongly, as opposed to stronger winds; in the case of the former, the average [carbon dioxide concentration] was = 3.76, in the case of the latter, the average was = 3.98. [line break added]

The measurements taken near Chambésy, when compared to observations in nearby Geneva, indicate no direct association, that is, when it rained in Geneva, carbon dioxide concentrations in Chambésy were lower and vice-versa. [line break added]

Saussure is of the opinion that sustained watering of the soil through rainfall has a stronger impact on the carbon dioxide concentration in the air, as opposed to a large amount of water falling at once. Moist soil as a consequence of repeated, weak rainfall decreases the temperature and consequently ambient carbon dioxide concentration, as opposed to heavy rainfall. In general, drought and freezing of the soil appears to increase ambient carbon dioxide. [line break added]

36 comparative measurements, in Chambésy and in the middle of Lake Geneva, the latter conducted 4 feet above the waterline, gave the following results (again, given in units per 10,000 units of air): in Chambésy = 4.60, on Lake Geneva = 4.39 [units of vol. per 10,000 units of air] carbon dioxide. Max. concentrations on Lake Geneva = 5.78, min. 3.42. [line break added]

30 comparative measurements, in Chambésy and on a street in Geneva, yielded the following results: in Chambésy = 4.37, in Geneva = 4.68. Measurements during daytime showed the same results, i.e., a higher concentration of carbon dioxide in the city; during nighttime, it was the other way round. [line break added]

Finally, carbon dioxide concentrations in the mountains were slightly higher than in the plains; yet, differences were small. Hence (again, in units per 10,000 units of air), at the same times of day, measurements taken at the Col de Faucille, which is 963m above Lake Geneva [the peak is at 1,322m above sea level] yielded the following results: 4.43; 4.54; 3.69; 3.60; 4.22; 3.95; in Chambésy: 4.14; 4.15; 3.87; 3.22; 3.55; 3.15; there were no significant differences to measurements taken at the peak of La Dôle at 1,267m above Lake Geneva [elevation 1,677m]. Moreover, no increase of carbon dioxide concentration was present at higher elevations during nighttime…

The sum of these measurements shows that ambient atmospheric air contains an average of no more than approx. 4/10,000 or 0.04 one-hundreds of carbon dioxide per unit of volume, and while this concentration fluctuates quite largely from its average but if considered against the total of ambient air, these fluctuations are but very small. We can neither judge whether the average concentration of carbon dioxide in the atmosphere remains constant or is subject to change over time, nor do we know the origins of this concentration. [line break added]

Large forests, such as those in the Département des Landes in France, which grow on sandy soil that does no contain any trace of carbon, get [their carbon dioxide] from this source [i.e., the atmosphere].

To sum up this long quote: in the late 1820s, Nicolas Théodore de Saussure conducted more than 200 measurements of ambient carbon dioxide in and near Geneva, Switzerland. These yielded the following results:

437, 468, 460, 439, 489, 443, 454, 369, 360, 422, 395, 414, 415, 337, 322, 355, 315, 489; the average of these 18 data points is approx. 410 ppm.

Today, we stand at 422-23 ppm.

How Saussure Measured Atmospheric Carbon Dioxide

The measurement of atmospheric carbon dioxide is conventionally attributed to Charles Keeling who, according to a piece written by Justin Gillis back in 2010 (NYT, 21 Dec. 2010),

made profound discoveries. One was that carbon dioxide oscillated slightly according to the seasons. Dr. Keeling realized the reason: most of the world’s land is in the Northern Hemisphere, and plants there were taking up carbon dioxide as they sprouted leaves and grew over the summer, then shedding it as the leaves died and decayed in the winter.

Given the above-related long quote from the 1850s Meyer’s Konversations-Lexicon, I move to declare this description of Mr. Keeling’s original contribution a wee bit overblown. Sure, I don’t know if he—or Mr. Gillis, for that matter—actually knew about Nicolas Théodore de Saussure (neither of his Wikipedia entries in English or German mention the above-related facts, nor does the Swiss Historical Dictionary), but one thing appears obvious: Mr. Keeling’s discoveries are not that original.

Neither does NASA’s dedicated ‘brief history of CO2 measurements’, written by Jet Propulsion Laboratory Historian Erik Conway mention Mr. Saussure.

Here is, by the way, a video by the Scripps Institute of how ‘modern’ CO2 measurements are conducted:

And this brings up the interesting issue of—how did Mr. Saussure conduct his measurements in the 1820s?

To answer this question, we turn, again, to Meyer’s Konversations-Lexicon, which provides the following answer (same source as linked above; again, my translation and emphases):

Atmospheric concentration of carbon dioxide is very low, hence its measurement requires high levels of precision and dedicated methodology…a) shaking of small amounts of Barium Hydroxide for 5-6 minutes, which is in an air-filled container whose volume is known; the air is removed mechanically after its [carbon dioxide] absorption and replaced 3-4 times. Then one collects the carbonised Barium Hydroxide and adds those traces of carbon that came to be on the interior parts of the container by adding hydrochloric acid and sodium bicarbonate…[line break added]

b) a bottle with a wide opening containing approx. 100g of water is half-filled with Barium Hydroxide and poured into a container of 14 litres with an opening of 6cm; to the latter is then attached a tap and sealed air-tight with a leather ring [as insulation]. Before sealing, air is pumped out of the container; then, the air sample is filled into the container, sealed, shaken frequently, and after two months the contained air is let out. Washed and dried, the remaining amount of barium shows the carbon dioxide concentration. This is the procedure employed by Théodore de Saussure for his initial measurements.

c) for his later measurements, Saussure used a slight modification of both methods. The main difference is to be found in the precise, minute-by-minute attention paid to gain the most precise results possible due to the trace amounts of atmospheric carbon dioxide. The container used can take in 35-45 litres and, upon the air having been pumped out, is filled only once with a to-be-tested air sample. To it, 100g of Barium Hydroxide is added and left for 8 days during which the container is shaken 20 times per day. Upon absorption [of carbon dioxide] by the Barium Hydroxide, the liquid is poured into a separate bottle, left until the carbonised Barium Hydroxide is settled, and subsequently washed with hydrochloric acid, to which is added sodium sulfate. Out of the amount of sulfuric Barium Hydroxide one then calculates the atmospheric concentration of carbon dioxide.

Now, I’m not a chemist or the like, but the method used by Mr. Saussure sounds suspiciously like the one used—and, admittedly, in a refined fashion (mainly by using machines instead of manual pumps)—by Mr. Keeling and his successors in the 1950s.

Bottom Lines

Why isn’t Mr. Saussure’s work mentioned in the annals of ‘climate change’?

Given the methodology used, Mr. Keeling’s contribution does not look as original as they may be.

Moreover, what about Mr. Saussure’s readings?

Could it be possible that, back in the 1820s, there were ambient carbon dioxide concentrations around 400 ppm? It is hard to say, but I would add that it could be that the manual pumps used by Mr. Saussure would not yield as standardised measurements as those achieved by mechanical equipment 130 years later by Mr. Keeling. Yet, the most likely distortion would be that the results might have yielded slightly higher CO2 concentrations than then-present—but by how much?

Source; emphasis mine.

Still, the difference cannot possibly be as big as the approx. 280 ppm reconstructed for the 1820s (by proxies—beware of data splicing) by the Scripps Institute.

Yet, what IF Mr. Saussure’s measurements are approximately accurate?—The most plausible answer is that the history of climate science (sic) would have to be re-written.

Moreover, there is ample evidence that carbon dioxide may not be the primary driving force of ‘global warming’ or ‘climate change’.

Personally, knowing a few things about how ‘the Science™’ works, I doubt that this will happen any time soon: way too many careers, funding streams, political and institutional ambitions rest on the presumption of anthropogenic climate change.

If that notion does not exist, or ‘only’ in a significantly modified version, many things would change.