Discussion > Leave Fossil Fuel in the Ground and We will Join it Very Soon
RR
My understanding has been that man is largely responsible for rising CO2 but that this rise has no effect on temperature as per Dr Moore.
Dung
From Dr Moore's speech:
"The Keeling curve of CO2 concentration in the Earth’s atmosphere since 1959 is the supposed smoking gun of catastrophic climate change. We presume CO2 was at 280 ppm at the beginning of the Industrial Revolution, before human activity could have caused a significant impact. I accept that most of the rise from 280 to 400 ppm is caused by human CO2 emissions with the possibility that some of it is due to outgassing from warming of the oceans."
Dung
From Dr Moore's speech:
"The past 150 million years has seen a steady drawing down of CO2 from the atmosphere. There are many components to this but what matters is the net effect, a removal on average of 37,000 tons of carbon from the atmosphere every year for 150 million years. The amount of CO2 in the atmosphere was reduced by about 90% during this period. This means that volcanic emissions of CO2 have been outweighed by the loss of carbon to calcium carbonate sediments on a multi-million year basis.
If this trend continues CO2 will inevitably fall to levels that threaten the survival of plants, which require a minimum of 150 ppm to survive. If plants die all the animals, insects, and other invertebrates that depend on plants for their survival will also die.
How long will it be at the present level of CO2 depletion until most or all of life on Earth is threatened with extinction by lack of CO2 in the atmosphere?"
Dung
Dung: are you arguing from authority? Dr Moore might be right, in that humans are largely responsible for the rising CO2, but on what is he basing this? The rise in CO2 has been more or less constant for some time, now, while the consumption of fossil fuels has been exponential – so, no obvious link. “Outgassing from warming oceans”? Again, where is the evidence? How much have the oceans warmed? (Please note that any figures given will be suspect, given the lack of information, historical and contemporary.) My understanding is that the human contribution to the increase is about 5%; what the cause of the other 95% is still up for conjecture.
Radical Rodent
RR
You remind me!
I am going to email GWPF to see if there are references for the figures given by Moore ^.^
Dung
RR
at least 50% of what Dr Moore said was stuff I already believed based on reading papers previously so I am not speaking from authority, I am saying my own thing with added details and more backing ^.^
Dung
Radical Rodent
Check the changes in carbon isotope ratios in atmospheric CO2.
Entropic man
Sorry, EM, but my carbon isotope ratio-meter has broken. I’ve ordered another off E-bay, but don’t expect to get it for a while, yet. Perhaps you could help out?
Meanwhile:
The last time we saw CO2 levels too low for plant photosynthesis was over 600 million years ago…Where do you get that information, EM? According to David Siegel, you might have faulty data.
Venus and Earth both have strong magnetic field.Half of that statement might not be correct, either (but can you trust Wiki?).
Radical Rodent
EM
Dr Moore also disagrees with you; speaking about the beginning of the Devonian period 400M years ago:
"There was no guarantee that fungi or any other decomposer species would develop the complex of enzymes required to digest lignin. If they had not, CO2, which had already been drawn down for the first time in Earth’s history to levels similar to todays, would have continued to decline as trees continued to grow and die. That is until CO2 approached the threshold of 150 ppm below which plants begin first to starve, then stop growing altogether, and then die."
Dung
EM
National Geographic implies that at the end of the Devonian Period (350M years ago) levels of CO2 were maybe close to the 150ppm level.
"The new life burgeoning on land apparently escaped the worst effects of the mass extinction that ended the Devonian. The main victims were marine creatures, with up to 70 percent of species wiped out. Reef-building communities almost completely disappeared. Theories put forward to explain this extinction include global cooling due to the re-glaciation of Gondwana, or reduced atmospheric levels of the greenhouse gas carbon dioxide because of the foresting of the continents. A major asteroid impact has also been suggested."
Dung
RadicalRodent
Carbon from fossi!l fuels is low in carbon 13, containing mostly carbon 12. Monitoring the rate of decrease in the proportion of carbon 13 in the atmosphere as it is diluted by fossil fuel CO2 gives you a way of measuring our CO2 emissions.
When new sea floor forms at the mid-atlantic ridge magnetic particles orient themselves to Earth's magnetic field. When the Earth's field reveres so does the orientation. Map the magnetic orientation of the rocks and you see stripes either side of the mid-atlantic ridge. Knowing how often the field reverses you can calculate how fast the rocks are moving.
My mistake regarding the magnetic field of Venus. Something to think about. Could be the slow rotation. It would be interesting to put some seismometers down.
Entropic man
Dung
Thank your lord for lignin decomposition. ☺
Entropic man
EM
I have no religious or climate faith.
According to The Smithsonian Museum of Natural History and indeed Dr Moore;
The Devonian Period was warm and dry but due to storage of CO2 in trees (before Lignin could be broken down), atmospheric CO2 was falling fast.
Falling levels of CO2 but warm and dry climate, CO2 does not cause temp change.
Dung
EM
The amount of C13 released by fossil fuels is dependent upon when and where the fossil fuel is 'laid down'. Fossil fuel from the mid to late Devonian Period will have a lot more C13 because atmospheric CO2 was low and so C4 plants would flourish and increase C13 content.
Dung
It also varies a lot with other biologies and conditions. The concentration of CO2 can itself change the (delta)C13 uptake within an organism. It's assumptions built on assumptions. Many of them initially plausible (especially to the 'climate afflicted'). But real-world scientists and engineers know from experience that at least one assumption in such a series will be badly wrong.
michael hart
RadicalRodent
Carbon from fossi!l fuels is low in carbon 13, containing mostly carbon 12. Monitoring the rate of decrease in the proportion of carbon 13 in the atmosphere as it is diluted by fossil fuel CO2 gives you a way of measuring our CO2 emissions.
(...)
Oct 18, 2015 at 1:58 PM Entropic man
Er, I think most things containing carbon contain "mostly" C12, EM, even those comparatively rich in C13.. But we know what you mean. However....
HUMAN EMISSION OF CO2And that brings us to modern changes; those actually observed.
The observed record of CO2 spans the last half-century. (slide) Extending it back to the proxy record indicates a systematic increase since the nineteenth century. In red (slide) is delta 13, the relative concentration of the two isotopes, carbon 13 and carbon 12. It has evidences a decline, mirroring the increase of CO2. Together, these proxy records comprise the 'smoking gun' of human emission. Vegetation is slightly leaner in carbon 13 than the atmosphere. So is its ancestor, fossil fuel. Coal and oil each derive from ancient vegetation. Emission from combustion of fossil fuel therefore add CO2 to the atmosphere, enriching its concentration. That's the green curve.
The CO2 added however is leaner in carbon 13 than the atmosphere, thereby diluting its concentration. That's the red curve. The glove fits.
In truth however, it's but one finger. Combustion of fossil fuel is one of many sources of CO2. Others involve a wide range of natural processes. Most are poorly documented. The reasonable interpretation is that opposite changes of CO2 and carbon 13 (the green and the red curve) are the signature of human emission. For this interpretation to be valid, other sources of CO2 - natural sources - must have the same concentration of carbon 13 as the atmosphere, which would then be left unchanged. That is, CO2 emitted by natural sources must not dilute carbon 13 in the atmosphere. The observed increase of CO2 and decrease in carbon 13 can then follow only from the human sources.
In reality, our knowledge of natural sources is limited. What we do know is that they are dynamic. Natural sources depend intrinsically on environmental conditions: cloud, moisture, temperature. Even on the prevailing ecosystem.
This is the estimated contribution from all sources and sinks. (slide) The human source is of order five gigatons per year. By comparison, the ocean emits of order 90. Land emits another 60. Total emission from natural sources is thus of order 150 gigatons per year - 96% of the total is approximately balanced by natural sinks which absorb about as much. The key word: approximately. Because natural sources and sinks are two orders of magnitude stronger, even a minor imbalance can overshadow the human sources. Moreover, if those sources involve carbon 13 leaner than the atmosphere, as many do, all bets are off *.
Murry Salby, Hamburg Lecture, 2013
* ie it's bollocks to assert that changing atmospheric C12/C13 ratio confirms that increasing atmospheric CO2 is due solely to combustion of fossil fuel.
["native" replaced by "natural". MA]
Martin A
Playing the "uncertainty" card, Martin?
Entropic man
Dung
"I have no religious or climate faith."
Me neither. I gave up Christianity for lent many decades ago.
I find it absurd to say "I believe in the greenhouse effect". It is like saying " I believe in gravity".
Entropic man
Then, of course, the “greenhouse effect” is nothing like the effect in a greenhouse. The principle warming of greenhouses is by inhibition of convection; the atmosphere is convecting away like mad. So much for your beliefs, eh?
Radical Rodent
Martin A
Unfortunately Salby has a few inaccuracies. Particularly, there are no natural processes significantly affecting the 13CC12C ratio over a century timescale.
Considering direct or indirect human emissions, they are almost entirely from biological storagev sources (permafrost peat decomposition, fossil fuels, deforestation, etc) will be 13C deficient because photosynthesis traps 12CO2 in preference to 13CO2. Release of any of these will dilute 13CO2.
CO2 dissolved in the oceans has the same ratio as in the atmosphere, but since the ocean is currently a net absorber of CO2 (90 units out, 92 in) it would not affect the isotope ratio much.
The other main source of atmospheric CO2 is vulcanism. This will have the "natural" inorganic proportion of 13CO2. Since volcanic CO2 is on the order of 1% of human emissions at will have little efect on isotope ratios.
Despite Salby's assertion that "In reality, our knowledge of natural sources is limited, the carbon cycle is well understood.
Entropic man
Radical Rodent
You will find that everyone agrees with you regarding the difference between them. The term "greenhouse effect" is a useful colloquial shorthand for the insulating effect of greenhouse gases, not an accurate description of the process taking place in the atmosphere.
Entropic man
Come on EM. A pretty picture with some arrows on it is not the same thing as something being "well understood" in the sense normally used in physical sciences.
The so-called Bern Model, adopted as gospel by the IPCC, with obvious physical impossibilities incorporated in it, stands witness to the fact that the carbon cycle is very far from "well understood". And that, in climate science, mere conjecture is taken as confirmed theory.
The greening of the Earth, widely publicised by Matt Ridley, seems to have come as a complete surprise to the carbon cycle "experts" who seem to lack even the most approximate understanding of the relationship between atmospheric CO2 concentration and ground level illumination, and absorption rate and, likewise, between climate as a global field and emission rate.
Martin A
Playing the "uncertainty" card, Martin?Oct 19, 2015 at 12:45 PM | Unregistered CommenterEntropic man
I certainly hope so, Entropic Man.
If a large corporation reports an annual change from a small profit to a small loss, then the company accountants can't usually get away with blaming it on an increased spending on office stationary.
Only in global-warming Cli-Sci are small numbers used to disguise ignorance of big numbers (and vice versa), a "science" where an uncertainty of measurement is regarded as an opportunity to make unsupportable claims, rather than a failing.
michael hart
I hope the following approximations will be of interest to followers of this thread.
Planetary Stocks of Carbon
Atmosphere 700 Gt 0.002%
Biosphere 1,170 Gt 0.004%
Hydrocarbons 12,000 Gt 0.040%
Oceans 37,600 Gt 0.125%
Sediments 30,000,000 Gt 99.8%
The Oceans contain over 95% of the total amount of carbon in the Ocean Atmosphere System
Over Phanerozoic time ( ie the last 600 million years) , sediments, mainly carbonates, shales, coal and other hydrocarbons, have sequestered over 30 million Gt of Carbon from the atmosphere and oceans, above and beyond additions from all sources ( eg volcanic eruptions, leakage from gas reservoirs, gas clathrates etc.)
During this period, ie in the last 600 my, atmosphericCO2 concentration has fallen from several thousand ppm to less than 500ppm
Most of the planetary stock of carbon probably now occurs in carbonate rocks in the form of calcium carbonate that has been abstracted from seawater by marine organisms which secreted aragonite to form their shells. The turnover half life of this material is very long ( tens of thousands to tens of millions of years)
Annual Carbon fluxes ( approximately):
Ocean to Atmosphere 90 Gt
Atmosphere to Ocean 92 Gt
Biosphere to Atmosphere 60 Gt
Atmosphere to Biosphere 61 Gt
Fossil fuel to Atmosphere 6 Gt
Sediments to Atmosphere +/- 0.3 Gt
Net Increment to Atmosphere 3 Gt ( ie +/- 50% of anthropogenic emmisions)
Atmosphere and Ocean to sediment 5 ? G
Volcanoes to Ocean and Atmosphere ??? ( most from submarine volcanoes at extensional plate boundaries?)
1 Gt = 10 9th tonnes,
CO2 is 33% C by weight
Paleoclimate Buff
Dung, the rise in CO2 dwarfs the input from human consumption of fossil fuels; there are other factors at play, here, and we have yet to discover most of them. Their present rise does not counter the observation that the general trend is downward, with the risk to all life as the levels ultimately approach zero (which 0.015% – or 0.00015 – is).