On the Influence of Carbonic Acid in the Air Upon the Temperature (1896) [pdf] | Hacker News Reader

On the Influence of Carbonic Acid in the Air Upon the Temperature (1896) [pdf]

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I'm not a climate-change denier, far from it, but it is worth noting that Svante Arrhenius made conclusions based on assumptions which are seriously flawed [1] [2]. The effects he described are at least four times exaggerated when compared with modern measurements.

[1] http://members.casema.nl/errenwijlens/co2/arrhrev.htm [2] http://members.casema.nl/errenwijlens/co2/arrhenius.html

One is reminded of the first calculation of black hole radius which ended up being right-ish due to two errors canceling each other out (See the first paragraph on page 135 at https://books.google.ie/books?id=v_6PbAfapSAC&lpg=PA135&ots=... )

Sure. But that was over a century ago. What's amazing is how good his understanding was.

Hindsight is 20/20, selection bias is a thing.

4x is within an order of magnitude. That's pretty good in technical terms...I mean in computing, we talk about bytes, kilobytes, megabytes, etc. which is a granularity of three orders of magnitude. Even in ordinary life we chunk time time into seconds, minutes, hours, days, weeks months, years, decades (kinda), centuries, etc...each approximately an order of magnitude.

Nearly 150 year old science is not accurate and has been replaced by modern theories, observations and measurements is surprising because...?

Very surprising! Look at the accuracy of the measurements of speed of light [1]. Even Eratosthenes (2nd century BC) approximations on the distance to and diameter of the sun is more accurate. The accuracy of scientific measurements at the time was in the order of parts per thousand. He took some lucky guesses, combined it with the science known at the time and presented it as new facts.

[1] http://www.speed-light.info/measure/speed_of_light_history.h...

Isn't that just the survivorship bias of "interestingly close" predictions? How many other predictions for the speed of light from 2000+ years ago do we still know about?

That's proving my point: the CO2 measurements were 400% besides the mark and shouldn't be categorised as scientific given the time-period. My comment tries to place Arrhenius into perspective.

>'Langley himself in a later memoir showed that the full moon, which certainly does not possess any sensible heat-absorbing atmosphere, has a "mean effective temperature" of about 45 C.'

This seems to be incorrect. The mean temperature of the moon is somewhere between 104-215K:

>'The mean temperature at the equator is 215.5 K with an average maximum of 392.3 K and average minimum of 94.3 K ( Fig. 19 ), representing an average change in temperature of ∼300 K. Average maximum and minimum temperatures in the polar regions (poleward of 85 °) are 202 K and 50 K respectively with a mean average temperature 104 K.' http://www.sciencedirect.com/science/article/pii/S0019103516...

I believe he was attempting to find the temperature of the sunlit moon, so was actually much too low.

If you're interested, there's some discussion of it here: http://www.jstor.org/stable/1638754

Whats the headline number in that article? Btw, I get ~310-320K average for the dayside, depending on albedo, etc assumptions. So 273 + 45 = 318 K is pretty close.

Here's a pretty good one from 40 years earlier. https://books.google.co.uk/books?id=6xhFAQAAMAAJ&pg=PA382#v=...

I wonder if the technology to convert sugar to ethanol exists in the 1960s, which would probably involve yeast. Even turning it to charcoal using sulfuric acid would be better. (background: https://www.nytimes.com/2016/09/13/well/eat/how-the-sugar-in...)

This is a non-sequitur.

Is there anything about the Influence of Carbonic Acid and Temperature Upon Vegetation?

Yes, it may increase it, but only it there is also enough water and nitrogene and it doesn't get too warm, which is not the case in many situations:

http://news.stanford.edu/pr/02/jasperplots124.html

Not 'may' but 'does'. CO2 provides an important source of carbon for plant growth. Commercial growers have used carbon dioxide to enhance greenhouse production for many years. The effect is now continental due to the increase in atomospheric CO2.

See “Human-induced greening of the northern extratropical land surface" Nature Climate Change 6, 959–963 (2016)

https://www.researchgate.net/publication/268280922_Ground_an...

It is not "does" but "may" since, as gp wrote, it "does not" when certain conditions are not met.

Apologies - my mistake! It's true that (not here!) in the rush to talk about its warming effect, many choose to ignore the positive effect of CO2 in the atmosphere <with respect> to its importance as a carbon source for plants.

Greening has of course taken place. To quote NASA, [ I think I've got this one right ] ...

"From a quarter to half of Earth’s vegetated lands has shown significant greening over the last 35 years largely due to rising levels of atmospheric carbon dioxide, according to a new study published in the journal Nature Climate Change on April 25. An international team of 32 authors from 24 institutions in eight countries led the effort, which involved using satellite data from NASA’s Moderate Resolution Imaging Spectrometer and the National Oceanic and Atmospheric Administration’s Advanced Very High Resolution Radiometer instruments to help determine the leaf area index, or amount of leaf cover, over the planet’s vegetated regions. The greening represents an increase in leaves on plants and trees equivalent in area to two times the continental United States."

https://www.nasa.gov/feature/goddard/2016/carbon-dioxide-fer...

This is not in the least surprising given extensive experimentation showing enhanced profitable growth for many plants (not all) with increased CO2. There will be upper limits of course.

>in the rush to talk about its warming effect, many choose to ignore the positive effect of CO2 in the atmosphere <with respect> to its importance as a carbon source for plants.

I'm not sure if you're meaning to, but your diction comes across as extremely biased. "Rush to talk" imputes a a hurriedness that does not seem justified based on any discussion I've seen. Also, a "choice" to "ignore" a particular effect, imputes a conscious decision to omit something that may be important. This uncharitable framing seems to be in error, as your own link doesn't seem very optimistic about greening countering climate change.

>“Studies have shown that plants acclimatize, or adjust, to rising carbon dioxide concentration and the fertilization effect diminishes over time.

The actual paper is quite interesting!

http://www.nature.com/nclimate/journal/v6/n8/full/nclimate30...

And it's very important to study, but I don't understand the need to impute bad motives to others not involved in the HN discussion.

You linked the wrong paper.

From that one's abstract: "We conclude that the observed greening in the Senegalese Sahel is primarily related to an increasing tree cover that caused satellite driven vegetation indices to increase with rainfall reversal."

I don't have a definite answer, but I've noticed that the plants in my garden are limited by light, and not anything else.

So I suspect extra CO2 won't make a difference.

But see here for an actual experiment on this: https://en.wikipedia.org/wiki/Free-air_concentration_enrichm...

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