OT: Something rotten in Denmark?

Yup, should have divided instead of multiplied. But it still looks like the O2 is declining faster than the CO2 accounts for, even if some of the burning is hydrocarbons.

At -19 PPM O2 fraction loss per year, we run out of oxygen in a mere

52,000 years.

Right; there aren't enough rusty cars to explain it.

John

In , J. Larkin wrote largely:

CO2 is increasing more like 2 PPM than 1 PPM per year, by volume and molecule count in the atmosphere as a whole.

Meanwhile, the

does indeed cite oxygen loss being 19 parts per million parts of oxygen. Since the atmosphere is 21% oxygen, I would multiply that 19 by the conversion factor of .21 O2 molecule per atmospheric molecule, and that is annual oxygen loss of

4 PPM of the atmosphere's molecules per year.

So at this point, O2 loss is twice CO2 gain, probably a little more since CO2 gain appears to me a little less than 2 parts per million atmospheric molecules per year.

Before complaining about the discrepancy continuing to exist by a factor of 2-plus, how about looking for explanations:

1. Not all CO2 from combustion of fossil fuels goes into the atmosphere - some goes into the oceans.

Atmosphere CO2 gain looks to me to be about 1.9 PPMV (of total atmosphere molecules) per year.

And as for how much goes into oceans - so far, close to half as much as goes into the atmosphere. Now we have combustion of carbon in fossil fuels accountinmg for oxygen removal at a rate of around 2.8 O2 molecules per million atmospheric molecules per year.

1. Fossil fuels do not have carbon as the only factor for combining with oxygen during combustion. Most fossil fuel combustion lately is liquid-at-room-temp-atmos-pressure petroleum products (averaging close to

2 hydrogen atoms per carbon atom) and natural gas and enriched natural gas (averaging close to 3 hydrogen atoms per carbon atom). Propane is a minor fossil fuel product, with 2.67 hydrogen atoms per carbon atom. Coal has some hydrocarbon content.

So I consider 2 hydrogen atoms per carbon atom to be a somewhat-high-side but usable-here oversimplification for accounting for oxygen removal by fossil fuel combustion being by oxidation of hyderogen rather than carbon. That means hydrogen oxidation removes a little less than half as much oxygen as carbon oxidation does.

Multiply the above 2.8 O2 molecules per million atmospheric molecules per year due to carbon oxidation alone by 1.5, and that is 4.2 as a high-side oversimplification.

At this point, oxygen loss at a rate of 4 O2 molecules per million atmospheric molecules, or 19 O2 molecules per million atmospheric molecules that are O2, is outright consistent!

- Don Klipstein ( snipped-for-privacy@misty.com)

I would apply to the -19 parts mer meg O2 molecules (per year) multiplying by the conversion factor of 21 O2 molecules per 100 atmosphere molecules.

That gives -4 O2 molecules per million atmosphere molecules (per year).

Make that more like 1.9 PPMV CO2 gain per year, plus about half as much being dissolved by the oceans, plus hydrogen in fossil fuels consuming a majority of half as much oxygen as the carbon in fossil fuels does.

- Don Klipstein ( snipped-for-privacy@misty.com)

100

Done already here?

unknown O2=20

atmosphere=20

Did you just reapply a correction for O2/N2 concentration?

year).

=20

as

much

largely:

=20

=20

variations.

=20

=20

Just to be fair, just exactly what are the units of O2 decrease and CO2=20 increase being used. Does it work out to the same number of atmospheric=20 molecules per year?

factor=20

-=20

as=20

molecules=20

with=20

to=20

gas

minor

=20

World consumption, See:

Over 4 billion billion short tons per year (!?)

over 85 million barrels per day.

365*85*55*8/2000 makes about 6.8 million billion tons per year (!?)

Did i get that conversion even with the right decimal point?.

=20

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suspended Monday

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nations,

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SUVs

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will=20

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Don, i do request and require that you be more careful with your units. Air column pressure is not air column mass.

Monday

Watched the self-immolation would be closer to the mark.

No. -19 is uncorrected. -100 is corrected in the wrong direction.

- Don Klipstein ( snipped-for-privacy@misty.com)

Scripps and Mauna Loa as cited here used different units. I applied a conversion factor to make them the same - the units in the Maina Loa cite, change of number of molecules of a particular gas per million molecules in the atmosphere.

O2 loss is a little over twice CO2 gain. However, a couple obvious factors do a good job of accounting for that. See below.

4.558 billion short tons per year.

OK, 4.14 billion metric tons, probably 3.9 billion metric tons carbon and 1/10 hydrogen atom per carbon atom.

I chose an order of magnitude consistent with "carbon budget" figures, one billionth of what that cite shows. I suspect they applied billion in error while the tonnage was already gigaton-plus for USA and China.

The numbers you show look good to me so far, and I get 80.3 ton/year per bbl/day. I get 6.8 billion short tons per year, looks to me good so far and consistent with carbon budget order of magnitude.

I would make that 6.17 billion metric tons of oil. I would oversimplify that to 2 hydrogen atoms per carbon atom, and multiplying 6.17 by 12/14 and get 5.29 billion metric tons of carbon.

As for natural gas - I am taking it a bit easy here, and latest figure good for carbon tonnage that I can pull in mere minutes is from 2004:

That was 1.4 metric gigatons of carbon per year. I would like to oversimplify natural gas to 2.667 hydrogen atoms per carbon atom, same as ethane, to make it easy.

I could try this:

249.3 billion cubic feet per day.

That works out to 5.553 E6 billion liters per year, and at 20 C 760 Torr pressure this is 2.31 E5 billion moles per year.

Since "USA-usual" ("my words") residential natural gas fairly oversimplifies to reasonably equivalent to ethane (unless I am wrong), and worldwide natural gas is probably more methane-rich than that and has some uncombustible gas content, and some of the natural gas is used for making plastic rather than being burned, I suspect that I will get a figure erroneously on the high side trying this:

231,000 billion moles per year * 2 carbon atoms per methane molecule *12E-6 metric ton per carbon atom = 5.54 gigatons carbon per year - sounds within-order-of-magnitude but quite high to me. So I will use the 1.4 gigatons of carbon from natural gas combustion in 2004, which sounds a little low to me.

Fuel metric gigatons H atoms per C per year C atom

Coal 3.9 .1 Oil 5.29 2 Nat-Gas 1.4 2.67

I try for a weighted average as such:

((3.9*.1)+(5.29*2)+1.4*2.67) / (3.9+5.29+1.4))

I get 1.39 hydrogen atoms per carbon atom here, for .3475 O2 molecule taken out by hydrogen per O2 molecule taken out by carbon.

Using 1.3475 instead of 1.5, I get 3.77 O2 molecules removed from the atmosphere by enough fossil fuel combustion to add 1.9 CO2 molecules to the atmosphere and .95 CO2 molecule to the oceans.

- Don Klipstein ( snipped-for-privacy@misty.com)

Monday

385 CO2 molecules / 1,000,000 atmosphere molecules

• 44 grams-per-mole for CO2 / 29 grams-per-mole for atmosphere

So far, this is .000584, unit is mass CO2 per mass atmosphere.

I had enough physics classes teach me that surface atmosphere pressure is the same as the weight per unit area of the atmosphere (air column). Of course, there would be a discrepancy where there is significant vertical acceleration in the air above - but worldwide average of that over time should be zero.

So I multiply 14.7 lb/in^2 by conversion factors of ...

1 "pound-mass" / 1 "pound weight" (valid for "standard Earth surface gravity)

• .45359 kg / 1 lb-mass

• 144 in^2 / 1 ft^2

• 5280^2 ft^2 / 1 mile^2

• 1 metric ton / 1,000 kg

At this point, I get atmosphere having 1.821 E6 metric tons per square mile.

Multiply this by

283 million square miles / 1 entire planet Earth surface

(I found an error of mine here - make that 197 rather than 283. I incorrectly converted 510,072,000 km^2 by multiplying by 3937^2/5280^2 - it should be 3281^2 (ft^2/km^2) / 5280^2 (f2^2/mi^2).) I should have converted area to metric terms while it was square inches

- I remember the conversion factors there well.)

and I get atmosphere mass of 5.27 E15 metric tons for the atmosphere. Actual will be slightly less since some of Earth's surface is significantly higher than sea level.

(Heck, I can probably find this in Wikipedia rather than calculate it... Lessee...)

"The average mass of the atmosphere is about 5 quadrillion (5x10^15) tonnes"

Multiply 5 E15 tons by .000585 unit mass CO2 per unit mass atmosphere and I get 2.925 E12 metric tons, or 2.925 E3 gigatons, of CO2 in Earth's atmosphere.

- Don Klipstein ( snipped-for-privacy@misty.com)

100 200000)/(800000)*10^6

unknown O2=20

atmosphere=20

year).

Hmmm. No explaination. Not good for credibility.

Show all the concentrations in molecules per million to discuss previous = and current. Or any other single comprehensible unit. Engineers can certainly work out the deltas and deltas per unit time.

largely:

our

are=20

in=20

been=20

variations.

100

as

=20

loss=20

21%=20

The stated change in the link is:

+++++ Oxygen levels are decreasing globally due to fossil-fuel burning. The = changes=20 are too small to have an impact on human health, but are of interest to = the=20 study of climate change and carbon dioxide. These plots show the = atmospheric O2=20 concentration relative to the level around 1985. The observed downward = trend=20 amounts to 19 'per meg' per year. _This corresponds to loosing 19 O2 = molecules=20 out of every 1 million O2 molecules in the atmosphere each year._

-----

So in molecules O2 per million molecules of air it IS about -100 ppm.

Adjustment inappropriate. Following calculations meaningless.

=20

=20

cite,

in=20

year?

factor=20

atmosphere -=20

as=20

molecules=20

with=20

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minor

has=20

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oversimplify=20

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for=20

hyderogen=20

less=20

molecules=20

suspended Monday

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nations,

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steel=20

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3*10^12=20

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atmospheric=20

5280=20

miles=20

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gravity)

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inches=20

it...

=20

Shazam. 2925 gigatons. That is a lot of CO2.

Now what are the coal consumption per year numbers (from another = subthread)?

85 gigatons/year world wide?

Previous and current concentration of O2 are not cited so much as the delta from one time to another, or rate of delta per year or other unit time.

The source cited by John Larkin said that over recent years O2 decline was at an annual rate of -19 "per meg".

(The Scripps cite saying -19 per meg O2 per year no longer remains included in the previously quoted material, and I have yet to find articles having it in Google news archive or anywhere findable by Google as of 7:28 PM EST12/27/09)

============

explains what "per meg" and ppm are, and gives a conversion factor for O2. 4.8 "per meg" is 1 ppm, and .2095 ppm is one "per meg".

- Don Klipstein ( snipped-for-privacy@misty.com)

That I agree with.

You are repeating John Larkin's error in converting per meg O2 to ppm of air.

There are 1 million O2 molecules in 4.8 million air molecules.

Losing 19 O2 molecules out of a million O2 molecules is losing 19 O2 molecules out of 4.8 million air molecules.

19 out of 4.8 million is 3.96 out of 1 million.

- Don Klipstein ( snipped-for-privacy@misty.com)

Monday

Should that be true, 85 gigatons of coal, with let's say 75 gigatons carbon, would add 275 gigatons of CO2 per year. (Remember, a CO2 molecule has 44/12 times as much mass as a carbon atom.)

If we repeat recent history of 1/3 of added CO2 being dissolved into the oceans, that makes 183 gigatons of CO2 being added to the 2925 in the atmosphere. Which is increase of 6.25% in one year. Plus whatever from combustion of petroleum products and natural gas!

Thankfully, what we are worrying about and debating on is smaller amounts of fossil fuel consumption, worth something like 10-12 gigatons of carbon per year, with around 6.5-8 gigatons or so per year not being dissolved into the oceans but accumulating in the atmosphere, becoming

44/12 of that or roughly 22-26 gigatons of CO2 atmospheric increase per year.

I did say a few days ago that atmospheric CO2 was increasing about 1.9 PPMV annually, with a very recent full year having for the year 385 PPMV. I somewhat remember that this was rate over past decade, and recent few years are probably a little worse - along with oceans dissolving a little more than 1/3 of the CO2 emissions. This 385 PPMV is up from 280 PPMV for "holocene pre-industrial-revolution baseline" of 280 PPMV. We are fretting about and debating effects and what needs to be done while we are on course to increasing atmospheric CO2 concentration to 500-600 PPMV by the end of this century.

- Don Klipstein ( snipped-for-privacy@misty.com)

about 100

200000)/(800000)*10^6

unknown O2=20

atmosphere=20

year).

previous=20

=20

=20

It seems i got my eye teeth crossed again.

largely:

our

are=20

ratio in=20

been=20

and=20

variations.

100

as

and=20

loss=20

21%=20

=20

changes=20

the=20

atmospheric O2=20

trend=20

molecules=20

of=20

I got myself crossed up good on that one.