Climate Change - the big debate

[ludo]

s2art said:

Re Missing sink.

ludo said:

That is incorrect, if you read the IPCC reports, they have a very good idea where the bulk of the CO2 goes, try performing a google image search for "carbon cycle" and you will find many diagrams like this one that show the scale of the fluxes (note that the ocean gives out 2 gigatons of carbon less than it takes in). So that objection is misinformed.

Nope. The missing sink is still there, and they do not know where it goes. There is work going on, but its certainly not clear at all.

http://earthobservatory.nasa.gov/Newsroom/view.php...


"To figure out exactly what is happening, we need improved models and more atmospheric observations."

perhaps you ought to heave read the whole article

article said:

For years, one of the biggest mysteries in climate science has been the question of what ultimately happens to the carbon emitted by motor vehicles, factories, deforestation, and other sources. Of the approximately 8 billion tons of carbon emitted each year, about 40 percent accumulates in the atmosphere and about 30 percent is absorbed by the oceans. Scientists believe that terrestrial ecosystems, especially trees, take up the remainder.

right, so the terrestrial ecosystem accounts for at most 2.4 billion tons

article said:

To find this terrestrial carbon sink, scientists have turned to computer models that combine worldwide wind patterns with measurements of carbon dioxide taken just above ground level. The models indicate that northern forests absorb about 2.4 billion tons per year. However, ground-based studies have tracked only about half that amount, leaving scientists to speculate about a "missing carbon sink" in the north.

which means that the missing sink accounts for at most 1.2 Gt of the 8 Gt that we emit, i.e. 10% at most, which is rather less than the 50% of human emissions you mentioned.

[ludo]

s2art said:

ludo said:

Actually Essenhigh's position has a much larger problem, namely that it can't explain why the annual rise in CO2 is less than human emissions (both of which are known with reasonable accuracy).

On the contrary, Essenhigh's position explains why the annual rise is less than the emissions. That is the crux of his theory!

No, it doesn't. His theory says that the environment is a net source, and the rise is not due to anthropogenic emissions, if that were true, the annual rise in CO2 would be greater than anthropogenic emissions, not less.

[im]

Ah-ha!

This is all far more gentlemanly and as a consequence far more enjoyable a read!

With this level of discourse I feel like I'm in a Uni lecture all over again

Keep it up chaps!




I'll be able to contribute when Climate meets Balance Sheet but until then...












...well, with Blib in attendance perhaps 'UNI' Lecture is stretching it...

[Spiritual_Beggar]

im said:

I'll be able to contribute when Climate meets Balance Sheet but until then...

But aren't they one and the same? Since te purpose of the 'former' is to prop-up the 'later'?

[s2art]

ludo said:

which means that the missing sink accounts for at most 1.2 Gt of the 8 Gt that we emit, i.e. 10% at most, which is rather less than the 50% of human emissions you mentioned.

Depends on where you get your figures from. I have seen estimates from 25-50%

Edited by s2art on Tuesday 13th October 17:12

[s2art]

ludo said:

s2art said:

ludo said:

Actually Essenhigh's position has a much larger problem, namely that it can't explain why the annual rise in CO2 is less than human emissions (both of which are known with reasonable accuracy).

On the contrary, Essenhigh's position explains why the annual rise is less than the emissions. That is the crux of his theory!

No, it doesn't. His theory says that the environment is a net source, and the rise is not due to anthropogenic emissions, if that were true, the annual rise in CO2 would be greater than anthropogenic emissions, not less.

Go back and read my explanation again. Its all about equilibria, and no the increase in CO2 would not be greater than anthropogenic emissions if the time to equilibrium is short. Precisely the opposite!

[kerplunk]

s2art said:

ludo said:

which means that the missing sink accounts for at most 1.2 Gt of the 8 Gt that we emit, i.e. 10% at most, which is rather less than the 50% of human emissions you mentioned.

Depends on where you get your figures from. I have seen estimates from 25-50%

Edited by s2art on Tuesday 13th October 17:12

never mind!

Edited by kerplunk on Tuesday 13th October 17:19

Edited by kerplunk on Tuesday 13th October 17:20

[ludo]

s2art said:

ludo said:

which means that the missing sink accounts for at most 1.2 Gt of the 8 Gt that we emit, i.e. 10% at most, which is rather less than the 50% of human emissions you mentioned.

Depends on where you get your figures from.

ETA if you get the from oil-related industries, as you have below, I am not all that surprised they are higher!

s2art said:

'It is easy to measure the missing sink. We know how much carbon we put into the atmosphere. For
example, in the year 2005 the world emitted 32.5 billion metric tons (mt) of CO2 into the atmosphere. We
also know how much CO2 is found in the atmosphere.
The mass of the Earth’s atmosphere is 5.148 x 1015 mt, and the concentration for 2008 was 386 ppmv.
For 2008 the increase in the atmosphere was 1.97 ppmv, or 15.4 billion mt. [Note: Volume concentration
must be corrected to mass concentration.] The difference or “missing sink,” is 17.1 billion mt and
represented 52.6 percent of emissions in 2008.
By comparison, 40 years ago, in 1968, we emitted 13.6 billion mt of CO2, and about 8.1 billion mt
accumulated in the atmosphere. The missing sink in that year was 5.5 billion mt, or 40.4 percent of 1968
emissions.'

http://docs.google.com/gview?a=v&q=cache:MHJ7y...

In that document they are (rather misleadingly) using "missing sink" to refer to the entire sink, conveniently forgetting that whe have a good idea of where most of it ends up (as mentioned in the other article you referenced).

Edited by ludo on Tuesday 13th October 17:22

[ludo]

kerplunk said:

s2art said:

ludo said:

which means that the missing sink accounts for at most 1.2 Gt of the 8 Gt that we emit, i.e. 10% at most, which is rather less than the 50% of human emissions you mentioned.

Depends on where you get your figures from. I have seen estimates from 25-50%

Edited by s2art on Tuesday 13th October 17:12

carbon vs Co2?

multiply or divide by 44/12 to convert. I have tried to differentiate between GTCo2 (e.g. the 29 figure) and GTC (as e.g. above), but apparently not as well as I should have!

[kerplunk]

ludo said:

kerplunk said:

s2art said:

ludo said:

which means that the missing sink accounts for at most 1.2 Gt of the 8 Gt that we emit, i.e. 10% at most, which is rather less than the 50% of human emissions you mentioned.

Depends on where you get your figures from. I have seen estimates from 25-50%

Edited by s2art on Tuesday 13th October 17:12

carbon vs Co2?

multiply or divide by 44/12 to convert. I have tried to differentiate between GTCo2 (e.g. the 29 figure) and GTC (as e.g. above), but apparently not as well as I should have!

ignore i was on a different track, thanks anyway

[Marquis_Rex]

Ludo the ardent climate change eco-warrior is here masquerading as a scientist

[Blib]

im said:

...well, with Blib in attendance perhaps 'UNI' Lecture is stretching it...

I resemble that remark.

[turbobloke]

s2art said:

ludo said:

s2art said:

ludo said:

Actually Essenhigh's position has a much larger problem, namely that it can't explain why the annual rise in CO2 is less than human emissions (both of which are known with reasonable accuracy).

On the contrary, Essenhigh's position explains why the annual rise is less than the emissions. That is the crux of his theory!

No, it doesn't. His theory says that the environment is a net source, and the rise is not due to anthropogenic emissions, if that were true, the annual rise in CO2 would be greater than anthropogenic emissions, not less.

Go back and read my explanation again. Its all about equilibria, and no the increase in CO2 would not be greater than anthropogenic emissions if the time to equilibrium is short. Precisely the opposite!

Precisely.

To be participating in social intercourse at this stage shows you have the patience of a uni lecturer saint. Just make sure you are protected

[turbobloke]

ludo said:

turbobloke said:

In (possible) answer to one specific question, I wonder if two quantities are being confused?

Half-life as described for dacay of the bomb isotope signal is the time taken for a sample with initial content N to fall to N/2. This will, obviously, be the same time as it takes to fall from N/2 to N/4 and so on.

Residence time is the average 'lifetime' of a molecule of gas in the atmosphere, i.e. the average time taken for a molecule of X to be removed. The picture created by this is complicated by the fact that the population of carbon dioxide molecules in the atmosphere isn't constant, which is where we came in.

Use of 'lifetime' is claimed by some to be confusing. Probably requires a risk assessment.

Depending on definition of residence time, you can get this, from a common definition:

half-life = ln 2 x residence time

I think this is the source of the confusion as analysis often forget the fact that there is an exchange going on, rather than simply a removal of CO2 molecules from the atmosphere.

Hmmmm.

In the above post quoted by ludo I said:

The picture created by this is complicated by the fact that the population of carbon dioxide molecules in the atmosphere isn't constant, which is where we came in.

ludo said:

I suspect this is where Essenhigh's error lies

There is no error in Essenhigh. The problems lie with you.

[turbobloke]

Hi keplunk.

You seem to be less time-limited. Care to share...your paleo? You offered a few ppmv and I'm about to see you, or raise, depending on the source

[FunkyGibbon]

Ludo we seem to be going round the same circles re: increase of CO2 in atmosphere as we did on Sunday...

FunkGibbon on Sunday said:

ludo said:

FunkyGibbon said:

ludo said:

Now that we both agree that the environment is a net sink, what is responsible for the rise in atmospheric CO2 if it is not fossil fuel use

I don't think anyone is denying that - of course if we add more CO2 to the atmosphere that will effect the CO2 levels (exact amount based on the state of the dynamic equilibrium at the time).

No, that is exactly what Essenhigh and turbobloke are denying.

That's not how I've read it - TB stated that 2 pages ago:

TurboBloke said:

On the basis of fundamental thermodynamics that even True Believers and the IPCC cannot overturn at whim, the carbon dioxide emitted by humans will have an effect on the atmospheric level

and a couple of posts up...

s2art said:

Nobody is saying that adding CO2 will not increase the amount in the atmosphere

my bold.

FunkGibbon on Sunday then said:

So, can you help answer my second point with some evidence of a causal correlation between CO2 levels and global temperatures?

Any news on this?

[ludo]

turbobloke said:

ludo said:

turbobloke said:

In (possible) answer to one specific question, I wonder if two quantities are being confused?

Half-life as described for dacay of the bomb isotope signal is the time taken for a sample with initial content N to fall to N/2. This will, obviously, be the same time as it takes to fall from N/2 to N/4 and so on.

Residence time is the average 'lifetime' of a molecule of gas in the atmosphere, i.e. the average time taken for a molecule of X to be removed. The picture created by this is complicated by the fact that the population of carbon dioxide molecules in the atmosphere isn't constant, which is where we came in.

Use of 'lifetime' is claimed by some to be confusing. Probably requires a risk assessment.

Depending on definition of residence time, you can get this, from a common definition:

half-life = ln 2 x residence time

I think this is the source of the confusion as analysis often forget the fact that there is an exchange going on, rather than simply a removal of CO2 molecules from the atmosphere.

Hmmmm.

In the above post quoted by ludo I said:

The picture created by this is complicated by the fact that the population of carbon dioxide molecules in the atmosphere isn't constant, which is where we came in.

The point that I was making is that you can't use the residence time of an individual molecule to work out the half life of a dollop of CO2 injected into the atmosphere, using the equation you gave, as that would ignore the fact that it is an exchange, not simply a loss of molecules from the atmosphere.

As I pointed out, if one CO2 molecule is released for each one captured, you can have a completely static concentration of CO2 in the atmosphere, and hence equilibrium, despite the fact that the residence time is finite. In that case, your equation would incorrectly predict a decay of atmospheric concentration.

[ludo]

FunkyGibbon said:

Ludo we seem to be going round the same circles re: increase of CO2 in atmosphere as we did on Sunday...

If we get agreement on whether the rise in CO2 is anthropogenic, I'd be happy to move on, however at the moment there isn't much point in going any further. The data is unequivocal on the source of CO2, it is more ambiguous how much warming it would cause, so if the mass balance argument can be dismissed by saying it is the "wrong paradigm", I would be wasting my time discussing anything more interesting than that. Given the non-engagement with my lengthy post made earlier on, I think my inital thought not to bother with this thread seems spot on in hindsight.

[s2art]

ludo said:

FunkyGibbon said:

Ludo we seem to be going round the same circles re: increase of CO2 in atmosphere as we did on Sunday...

If we get agreement on whether the rise in CO2 is anthropogenic, I'd be happy to move on, however at the moment there isn't much point in going any further. The data is unequivocal on the source of CO2, it is more ambiguous how much warming it would cause, so if the mass balance argument can be dismissed by saying it is the "wrong paradigm", I would be wasting my time discussing anything more interesting than that. Given the non-engagement with my lengthy post made earlier on, I think my inital thought not to bother with this thread seems spot on in hindsight.

I dont think you have understood a word that has been posted. We have been discussing two different positions, the IPCC long time to equilibrium and the Essenhigh short time to equilibrium. Only the IPCC position allows for the rise in CO2 to be anthropogenic, and this is contradicted by a lot of evidence. It is by no means 'uniquivocal' on the source of the CO2, in fact its the opposite.
Perhaps Segalstad can explain it better than I.

http://folk.uio.no/tomvs/esef/ESEF3VO2.htm

[turbobloke]

ludo said:

FunkyGibbon said:

Ludo we seem to be going round the same circles re: increase of CO2 in atmosphere as we did on Sunday...

If we get agreement on whether the rise in CO2 is anthropogenic, I'd be happy to move on...

How can you expect that when the evidence, via data, shows clearly that it's not?

Is it seen to be non-suckerfishery to say that you are operating out of your depth? Seek a shallower pond, unless you can get a crash course in kinetics and thermodynamics, as it's absolutely pointless discussing this with you when, even after alternatively worded and very clear explanations from more than one person, you are still no further along the path of enlightenment.

As to simply 'demanding' that people agree that the rise in tax gas is anthropogenic, in order to stop your odd posts, of itself that's a non-starter since in a scientific discipline the science isn't determined by negotiation or consensus. Admittedly the IPCC see otherwise but that's their problem and needn't be yours.

The carbon dioxide level increase we've seen is not purely due to human emissions. Overwhelming evidence has already been adduced, so you too must have been overwhelmed. The interesting remaining question is to the proportion issue and the Razor of Occam applied by Spencer won't be far off.

Edited by turbobloke on Tuesday 13th October 18:55