# Is Argon A Greenhouse Gas?s

8 replies to this topic

### #1 SaxonViolence

SaxonViolence

Understanding

• Members
• 315 posts

Posted 22 April 2019 - 02:48 PM

Friends.

If we added some Argon into Earth's atmosphere—purely as a thought experiment….

Say between 1 and 2 PSI...

Would the net effect be warming or cooling to the Earth's climate?

I remember reading a very old experiment—early 60's—trying to determine if plant life could survive on Mars. Back then they believed that there was—or might be—a fair amount of Argon in the Martian atmosphere. They discovered that plants can tolerate killing frost's much better when there is some Argon in the atmosphere—God knows why.

Since then, when phantasizing about building worlds to order, I always like to imagine about 1.5 PSI of Argon in the atmosphere,

Then I got to wondering—would the Argontend to reflect sunlight and cause my hypothetical world to freeze?

Saxon Violence

PS: I browsed that article ONCE back in the early 70's. Please don't ask for a reference. Wish that I knew.

Edited by SaxonViolence, 22 April 2019 - 03:35 PM.

All I know is that I know nothing.

• Members
• 1209 posts

Posted 22 April 2019 - 10:21 PM

Argon is the third most abundant gas in the atmosphere after nitrogen and oxygen.  It is a noble gas, as in inert and non-reactive, so the planet has all of the naturally occurring Argon it will ever have.  Argon is also not a greenhouse gas (see second link).

https://en.wikipedia.org/wiki/Argon

https://sciencing.co...-gas-23837.html

• exchemist and OceanBreeze like this

### #3 exchemist

exchemist

Creating

• Members
• 2818 posts

Posted 23 April 2019 - 03:01 AM

Argon is the third most abundant gas in the atmosphere after nitrogen and oxygen.  It is a noble gas, as in inert and non-reactive, so the planet has all of the naturally occurring Argon it will ever have.  Argon is also not a greenhouse gas (see second link).

https://en.wikipedia.org/wiki/Argon

https://sciencing.co...-gas-23837.html

In line with the second link, I was not expecting Argon to absorb in the IR, as it is monatomic and IR absorption bands arise from polar molecules.

However I looked it up and was intrigued to discover that Argon does in fact absorb in the IR! There are apparently sufficient electronic energy levels close to one another (and of different angular momentum) that electrons can be promoted from one to the next by IR photons. However this gives rise only to a line spectrum, rather than a band spectrum, so only IR radiation at a number of fairly exact frequencies is absorbed by Argon, as opposed to the broad bands of absorption one gets from polar molecules such as CO2. At all other frequencies it is transparent to IR.

• OceanBreeze likes this

### #4 OceanBreeze

OceanBreeze

Creating

• Moderators
• 1073 posts

Posted 23 April 2019 - 03:45 AM

In line with the second link, I was not expecting Argon to absorb in the IR, as it is monatomic and IR absorption bands arise from polar molecules.

However I looked it up and was intrigued to discover that Argon does in fact absorb in the IR! There are apparently sufficient electronic energy levels close to one another (and of different angular momentum) that electrons can be promoted from one to the next by IR photons. However this gives rise only to a line spectrum, rather than a band spectrum, so only IR radiation at a number of fairly exact frequencies is absorbed by Argon, as opposed to the broad bands of absorption one gets from polar molecules such as CO2. At all other frequencies it is transparent to IR.

A great deal of the ocean research done on board ship involves the use of certain tracers to monitor currents, temperature, salinity etc. and I know that certain isotopes of argon are among the tracers monitored.

Unfortunately, this link is only an abstract, but there is enough information there to ask my question:

The link says that "(argon is) the only rare gas measured both by mass spectrometry and gas chromatography"

I am surprised by that statement. Any idea as to why argon is the only rare gas to be measured by both methods?

### #5 exchemist

exchemist

Creating

• Members
• 2818 posts

Posted 23 April 2019 - 10:58 AM

A great deal of the ocean research done on board ship involves the use of certain tracers to monitor currents, temperature, salinity etc. and I know that certain isotopes of argon are among the tracers monitored.

Unfortunately, this link is only an abstract, but there is enough information there to ask my question:

The link says that "(argon is) the only rare gas measured both by mass spectrometry and gas chromatography"

I am surprised by that statement. Any idea as to why argon is the only rare gas to be measured by both methods?

I'm surprised by it too. Argon is however used as a carrier gas in both techniques, I gather.

I don't have access to the complete article. Does that not clarify at all?

All I know is that I know nothing.

• Members
• 1209 posts

Posted 28 April 2019 - 06:44 PM

I remember reading a very old experiment—early 60's—trying to determine if plant life could survive on Mars. Back then they believed that there was—or might be—a fair amount of Argon in the Martian atmosphere. They discovered that plants can tolerate killing frost's much better when there is some Argon in the atmosphere—God knows why.

Just out of curiosity, shouldn't your handle be SaxonViolins?

All I know is that I know nothing.

• Members
• 1209 posts

Posted 28 April 2019 - 07:05 PM

While we are on the topic of atmosphere, the May issue of Discover magazine had a handy dandy little chart in the sidebar of page 41. Apologies to Discover for copying.

Earth                                                     Mars

Nitrogen 77%                                        Nitrogen 2.7%

Argon 1%                                              Argon 1.6%

Oxygen 21%                                         Oxygen 0.13%

Carbon Dioxide 0.038%                        Carbon Dioxide 95.3%

Gravity 2.66 time Mars                          Gravity 0.378 time Earth

Average temperature 57F                    Average temperature -81F

Mars also had listed 0.03% water vapor, 0.01% Nitric Oxide, and 0.21% other gases.

• exchemist likes this

### #8 exchemist

exchemist

Creating

• Members
• 2818 posts

Posted 29 April 2019 - 02:53 AM

While we are on the topic of atmosphere, the May issue of Discover magazine had a handy dandy little chart in the sidebar of page 41. Apologies to Discover for copying.

Earth                                                     Mars

Nitrogen 77%                                        Nitrogen 2.7%

Argon 1%                                              Argon 1.6%

Oxygen 21%                                         Oxygen 0.13%

Carbon Dioxide 0.038%                        Carbon Dioxide 95.3%

Gravity 2.66 time Mars                          Gravity 0.378 time Earth

Average temperature 57F                    Average temperature -81F

Mars also had listed 0.03% water vapor, 0.01% Nitric Oxide, and 0.21% other gases.

The molecular weights of N2, Ar, O2 and CO2 are 28, 40, 32 and 44.

The kinetic energy of gas molecules is proportional to temperature, meaning that heavier molecules move more slowly at a given temperature.

The escape velocity for Mars is half that for Earth.

So i imagine one reason why Mars has proportionately less nitrogen than argon or CO2 may be the more rapid escape of the lighter gases into space.

In the case of oxygen of course it is the Earth that has an anomalously high proportion of it, due to the release of O2 from photosynthesis.

### #9 SaxonViolence

SaxonViolence

Understanding

• Members
• 315 posts

Posted 23 May 2019 - 01:01 PM

Yeah,

My thoughts were toward a hypothetical atmosphere on a fictional planet. If I wrote that the Argon content there was 2-PSI, I didn't want some science type dude to say:

"If it was, your planet would be suffering from runaway greenhouse effect…"

I don't know that Mars has a relative abundance of Argon. I only know that way back in the Late '60s when that article was written that SOME scientists THOUGHT that Mars had beaucoup Argon.

On the other hand, I'm not 100% certain that an Argon rich atmosphere increases resistance to hard overnight frosts—only that the article quoted SOME sources that indicated that it MIGHT.

Anyway, whenever I design an imaginary place, I always like to stick a generous amount of Argon in the atmosphere. It just occurred to me that I might be cursing my imaginary places to "The Runaway Venus Effect."

You have a good memory. Yes, the original genesis of that screen-name was that old SNL Sketch featuring "Sax and Violins."

The name evolved. It's been like 40-years since I heard the original pun.

Saxon Violence