I’ve been doing some more than usual research as of late to answer for myself a specific question about CO2 respiration and the amount of man-made CO2 that is reatined versus naturally generated CO2. In doing so I’ve been in some discussion with some people I share an email list with.
One of them pointed out this ESRL (Earth Systems Research Laboratory) animation to me. I immediately found it intriguing because of the disparity between hemispheres:
CO2 (C13) January 1996 to December, 2007
From ESRL:
This movie shows the latitude distribution (from south-to-north) of average monthly values derived from the GLOBALVIEW extended records. Cyan circles are average monthly values from sampling locations thought to be regionally representative; pluses are average values from locations thought to be influenced by local sources and sinks. A smooth curve is fitted to the representative measurements when sufficient data exist.
Isotopic measurements from NOAA air samples are made by the University of Colorado (CU), Institute of Arctic and Alpine Research (INSTAAR), Stable Isotope Laboratory (SIL).
They caution that this is a derived product, (due to processing, smoothing etc) and does no longer represent raw data on CO2C13, along with other caveats such as this:
These and other measurements have been widely used to constrain atmospheric models that derive plausible source/sink scenarios. Serious obstacles to this approach are the paucity of sampling sites and the lack of temporal continuity among observations from different locations. Consequently, there is the potential for models to misinterpret these spatial and temporal gaps resulting in derived source/sink scenarios that are unduly influenced by the sampling distribution. GLOBALVIEW-CO213 is an attempt to address these issues of temporal discontinuity and data sparseness and is a tool intended for use in carbon cycle modeling.
But still, it is quite informative. Here is a map of the ESRL station distribution. Not all of them are CO2 surface monitoring stations.
Note how the southern hemisphere’s (90S to EQ)CO2C13 content remains nearly steady over the 12 year period, while the northern hemisphere shows major seasonal variation. The greatest variation is at the northernmost latitude, with data that likely comes from the Alert, Nunavut, Canada and the Ny-Alesund, Svalbard ESRL monitoring station.
You can see by the seasonal variation in the movie that when it is warmer, more CO2C13 is being released into the atmosphere, when it is colder, more CO2 C13 is taken out. It demonstrates a short term linkage between CO2 and temperature. While the “paucity of sampling” in the Southern Hemisphere is evident from the map, I find it curious that there is virtually no seasonal variation there, compared to the dance of the datapoints north of the equator, the ones south of the equator are wallflowers.
h/t to Allan Siddons
“when it is warmer, more CO2C13 is being released into the atmosphere, when it is colder, mores CO2 C13 is taken out.”
That seems backwards. The typical CO2 flux graph show the highest annual CO2 in winter as most vegetation in the higher latitudes go dormant and ice makes impossible the taking of CO2 out of the atmosphere.
Could it be summer soil respiration? I’m not an expert on this, but I wonder if the greater land mass at higher northern latitudes that are exposed during the summer months are putting out more C13 during the summer resulting in higher summer readings?
Could it be the shaking tail in the NH is partly a result of all the SH stations being at or near sea level, whereas many of the NH stations are at much higher elevations?
There is something I mentioned long ago in RC, and can be seen in the graphs. The ammount by which CO2 rises every year is now bigger than it was in the 60’s or earlier. However this is something that affects the winter increase only: the increase from the December (aprox) minimum to the following August (aprox) maximum has been getting bigger and bigger, from about 6.5 ppm in the 60’s to about 8 ppm now. However, the reduction between the August (aprox) maximum to the following December (aprox) minimum has kept quite stable at 6 ppm every year since the 60’s.
Now, we have been increasing our CO2 emissions all year, haven’t we? We should have seen an increase in the winter CO2 release AS WELL AS a reduction in the summer uptake. But the CO2 uptake in the summer is the same as before in spite of us humans emitting a huge ammount of CO2 more in those months than we did in the 60’s.
I posted this in RC as proof of a positive response from Nature to the increase of CO2: plants grow more and uptake more CO2. Plants are mostly in the NH and grow in the summer, so we see the response there. However Gavin Smith told me that I was wrong. We see that in the summer because the Southern Oceans are cold at that time and uptake a lot more CO2, and they uptake more than before because there is more CO2 to uptake. You know, ocean acidification and all that stuff.
However the graph we see here thanks to Anthony proves that wrong. If the main cause for CO2 uptake and release was in the temperature of the Southern Oceans instead of plants respiration, the big seasonal variation should be in the Southern Hemisphere, not in the northern one.
This is also seen in the AIRS animations, in the form of maps.
All that water in the southern hemisphere?
For me it says that the land biomass is breathing hard. The sea biomass is already swimming in a sink/source of CO2, a big buffer, it does not need the heat as the northern hemisphere land mass does to grow. The more north the more the heat is necessary for spring. It is march/april for bloom and absoprption, september october for decay and release.
Pardon, there is a mistake there. I meant increase between October and June, and reduction between June and October. Mistake happened because of the moths I use to detect the ratio of increase and reduction every year. In August I get the maximum minus the minimum of the previous 12 months concentrations to get the winter increase, as it always begins post-August (september or october) and ends before the following august (may or june), and in December I do the oposite to get the reduction.
Why do you find it curious?
Antarctica is a vast very cold continent with little vegetation surrounded by very cold seas and a very stable wind pattern around it to mix atmospheric gasses.
The northern hemisphere contains a lot of land with vegetation the wind patterns are less stable and seasonal temperature variations much larger.
Incidentally this hemispheric pattern shows up well on the Airs satellite photos. Note the high level of CO2 in the tropical regions.
Which only goes to show it is unwise to think that the proportion of CO2 is either a constant throughout the atmosphere and indeed throughout the year: or that Antarctica is a very good place to sample ice cores and deduce past climate either in the northern hemisphere or indeed over much of the globe.
Antarctica has a climate all its own.
Kindest Regards
This figure seems to be a new way to visualize the annual variation of CO2 content, as seen, e.g. in the oscillations of the Mauna Loa data. There is a winter peak and a summer minimum, explainable by heating and plant growth on the land masses of the Northern Hemisphere. In comparison, population in those parts of the Southern Hemisphere, which lie in latitudes south of the tropic of capricorn, is relatively low, since the land area there is quite small compared to NH.
Anthony,
You haven’t given much emphasis to the fact that these are Carbon-13 ratio numbers, not raw CO2. They are intended to track CO2 of fossil fuel origin. That’s the main reason for the hemisphere imbalance.
REPLY: I mentioned CO2C13 seven times in the post. It seems enough. – Anthony
Glenn,
“Could it be the shaking tail in the NH is partly a result of all the SH stations being at or near sea level, whereas many of the NH stations are at much higher elevations?”
You have identified one, of many, problems associated with sampling, something the mining industry had to come to grips with last century when estimating mineral ore reserves, (figuring exactly how much metal is in an orebody from a minimum number of samples without making too much of a stuff up. Steve McIntyre might add to this).
It’s basically what we describe as sample support and related to the statiscal sin of mixing oranges and apples.
Firstly it requires a good understanding of the physical structure of the object being sampled. In this case the chemical composition of the atmosphere vs. height, hence your question.
You have identified another climatic minefield with your innocent question.
🙂
Questions (and I hope they are not too dumb).
1. Isn’t the dC13CO2 (ratio) supposed to somehow be indicative of anthropogenic (fossil) CO2 vs. “natural” C02?
2. Isn’t the thinking that the more negative that dC13C02 is, the more anthro the CO2 is?
3. The most negative states appear to be in the NH in winter/spring (~May), and the least negative in the NH again in summer/fall (~Sept). What does that indicate about anthro vs natural CO2 emissions?
Sorry if these questions are too uneducated.
I wonder if we are seeing a second-order effect and not a reflection of the actual CO2 concentration? These data refer to the C13 isotope. Could it be that its the ratio C12/C13 that’s changing over the seasons which we see here?
What about this: suppose fossil fuel carbon has a lower C13 fraction than in the biosphere (because its has been burried for a long time and is depleted by decay?). If you burn it predominatly in winter you would expect a slightly lower C13 fraction compared with summer, in particular around Northern lattitudes 30-50 where most of the production is.
Anybody know any data to support or refute this idea? e.g. what exactly is the C13 content of fossil carbon in coal or natural gas?
Further to my earlier entry, I found this url, which may explain it.
http://cat.inist.fr/?aModele=afficheN&cpsidt=16626035
Any global warming caused by 350ppm CO2 in the air pales into insignificance compared with that produced by moisture. Yet even Al Gore et al does not refer to moisture as a GHG.
Plants preferentially take up C12. The vast majority of the Earth’s vegetation is in the northern hemisphere. Thus, during the northern hemisphere summer, a lot of CO2 is being removed from the atmosphere, and more of it has a C12 molecule than a C13 molecule. Hence the seasonal drop in C13 in the northern hemisphere but little variation in the south.
Fossil fuels are ex-plants. Thus, they contain more C12 than C13 in their carbon-based molecules. Thus, by burning them and releasing a large quantity of CO2, we are causing the atmosphere to contain less C13 than it otherwise would.
So, when looking at the isotopes, you see that there is a long-term downward trend in δC13, and superimposed on that is an annual cycle.
This is a great animation showing that northern hemisphere vegetation controls the up and down seasonal cycle of CO2.
The oceans wouldn’t provide such a signal even though they also oscillate with the seasons since the southern ocean also warms and cools with the seasons and there is no signal there.
It is a little curious the northern hemisphere seasonal signal varies more as you go north whereas one would expect the max seasonal signal to be in the mid-northern-latitudes (where there is greater growth and die-off of plants with the season). But the signal seems to vary more as you go progressively farther north.
We also know that the temperatures affect the annual growth rate of CO2 (by as much as +/-50%). I think we have to conclude this is due to the vegetative response rather than the oceans.
This would also indicate that northern hemipshere CO2 sinks provided through vegetation (forests and pastureland) will grow progressively more effective as global warming temperatures rise (slightly). There was a study out last week that showed tropical forests are sinking/growing more rapidly with the slightly warmer world.
Regarding my comments above about the CO2 sinks and warmer conditions, I think I have to pull those comments since it is not clear enough right now to say that. Sorry.
Rachel (03:22:35) : Plants preferentially take up C12.
Thank you,
I did not know that but I was actually wondering about it the other day (God knows why). I just googled it and came up with Kinetic isotope effect.
That was NOT covered in my two freshman chemistry classes at Georgia Tech in 1974.
Rachel (03:22:35) : The vast majority of the Earth’s vegetation is in the northern hemisphere.
I’m wondering about this. There is an awful lot of algae in the ocean.
It struck me odd that the X-axis is sin(lat) instead of just the latitude, then I realized it adjusts for the declining land area of bands of latitude as you head away from the equator. For those of us living near latitude 45, we show up at sin(+/-45) = +/-0.7.
Good confirmation that CO2 solubility in water drops off quickly as temperatures rise above 0C.
http://wattsupwiththat.files.wordpress.com/2008/04/co2_solubility_h2o.jpg?w=516&h=386
As explained here:
http://wattsupwiththat.com/2009/02/20/basic-geology-part-2-co2-in-the-atmosphere-and-ocean/
Interesting post, it says something about the well mixed assumptions in at least some models. The satellite crash the other day was really bad news, It would have gone a long way to understanding the magnitude of sources and sinks just by it’s area of coverage. I wonder if the JAXA version has similar capabilities.
Working on the antarctic paper, I did a plot last night which shows how the spatial weighting of surface station data by RegEM was not maintained for calculation of trend. It looks like a pretty big issue to me.
http://noconsensus.wordpress.com/2009/02/25/correlation-of-reconstructions/
R Stevenson,
Water vapor is indeed a GHG, but is not mentioned because it is a feedback — it cannot CAUSE a change in climate. It has a very short atmospheric lifetime (about a week), compared to CO2 (around 250 years). CO2 that ends up in the atmosphere stays there for a long time, while water vapor in the atmosphere quickly condenses as temperatures drop. Then, when temperatures rise again, water quickly evaporates.
So, it is true that water vapor makes the largest contribution to the TOTAL greenhouse effect, but it cannot create a CHANGE in the effect. It only amplifies the changes created by other forcings, such as CO2, methane, the Sun, etc.
Perhaps this guest post by Dr. Spencer last year on the C13/C12 ratio might be of interest to readers of this current post:
http://wattsupwiththat.com/2008/01/28/spencer-pt2-more-co2-peculiarities-the-c13c12-isotope-ratio/
Rachel says:
Bingo…And, I might add that while eventually the CO2 gets to be pretty well-mixed throughout the globe, this takes a while…particularly to mix between the two hemispheres…so that these shorter timescale oscillations are seen.
The sky is falling:
http://www.sciencedaily.com/releases/2008/02/080229075228.htm
Evacuate the coastal areas immediately.
off topic.There is an interesting article at The Register about a new Japanese break with IPCC views on climate http://www.theregister.co.uk/2009/02/25/jstor_climate_report_translation/
News from today, though it looks to be from last year as above.
http://www.foxnews.com/story/0,2933,499886,00.html
Anthony:
This is off topic, but I hope timely. I was reading this morning in Yahoo about the Great Glacier advance into the sea from Antarctica and it was all attributed to the Glacier melting. The story said that the ice is now moving faster on it’s way to the sea. Am I missing something here?
When Glaciers advance, is that not often a sign that they are growing? If the Antarctic Glacier grows, where could it go, but into the sea. The story is a pop science, short on facts, but it should be easy to establish – is the ice cap larger in the center and growing or melting and thus allowing the ice to “slide away”.
I believe this is a critical point and a critical juncture in the AGW debate, if the Media is allowed to say that the advancing Glacier is melting; they will say this will lead to Ocean’s rising, and that the World is doomed unless we start charging for CO2 emmissions. Alot of damage will get done legislatively in th U.S. before the “re-print” gets out that the Glacier may be, in fact growing.
Can anyone help me as to which is occurring? Thanks!
The chart brings into question the number of sites and the methods of collection of the data. I suspect that there are very few sites and very few measurements taken daily. Much like the GISS ground stations for temperature but with dramatically reduced locations. Fascinating that we are intent on regulating something that we apparently know so little about.
This seems to correspond to PDO El Nino patterns during this same time period. It will be interesting to see what happens during the colder flip side of the PDO, especially when it coincides with the Atlantic oscillation cold phase.
R Stevenson says:
Water vapor is a greenhouse gas. However, it is not one that we can currently affect the concentration of through emissions of water vapor because of its higher concentration and shorter residence time in the atmosphere and the great availability of water in the liquid form to be evaporated. The way we can change the amount of water vapor in the atmosphere is by causing warming by increasing CO2 concentrations which then causes the amount of water vapor in the atmosphere to increase. And, indeed this feedback due to water vapor causes an increase in the warming effect due to forcings such as increases in CO2.
This is often summarized by saying that water vapor is a feedback, not a forcing.
Pardon if this is a stupid question, but could someone tell me what the Y-axis represents? Apparently it’s a log scale since it’s negative. Is it
1. the ratio of C13 to C12,
2. the ratio of C(13)O2 to total atmosphere, or
3. something else?
I would also wonder about a comparison to SST’s during this same time period by hemisphere. But I still think that sinks, which are likely more spread out than sources, are not being adequately measured. CO2 is escaping somewhere. The paucity of measuring devices at the surface (whether they are ground, tower, or balloon) cannot ever adequately measure CO2. The only way to go is satellite. By the way, another reason why the SH does not appear to vary as much in isotope percentage is that maybe there are more plants in the SH that prefer or are not picky about isotopes.
No one has mentioned the thing *I* found most striking about this movie:
Focus on the left hand side, not the right. Over the period covered, the SOUTHERN hemisphere value actually drops from -7.8 to -8.2.
The jump is really noticeable when the movie resets as the line suddenly jumps back up.
In case anyone was wondering:
δ13C = [ (13C/12C) sample / (13C/12C) reference – 1 ] x 1000
reference samples are also discussed here:
http://www.esrl.noaa.gov/gmd/ccgg/globalview/co2c13/co2c13_method.html
I still don’t see what the reference represents (reference is “normal” compared to what and how that applies to historical records), so if anyone has any insight I’d appreciate it…
You all are phylum bigots!!!
The vast majority of biological mass is bacteria in soil. The next biggest group is fungi.
They almost exclusively respire carbon from consuming plant and other matter in the soil. Some of that carbon stays in the soil and some is emitted.
If you do the math, a soil with 5% carbon content holds ALOT Of carbon. In plowed soils, the bacteria content is very high in ratio to plants. Many soils have lost carbon over time, due to agirculture, putting most of it into the air. This alone could account for the rise of CO2 over the last few decades. Where did it go??
Different kinds of bacteria have different growth rates depending on the temperature of the soil and the bits of sugar emitted by plant roots around them. The respiration contents ( CO2, H2O, O2 ) of tundra are very different from those of a grassland which are very different from a mature forest.
While people surmise about what plants do, they ignore the role of bacteria and fungi in the equation.
When this is all said and done, I think we are going to find that the biosphere of the Earth has been running down over time due to a decreasing rate of carbon emissions from bacteria and volcanoes. Carbon is the base currency of the Earth’s ecology and without it, the ecology will fail.
What is there behind all this CO2 issue?, back to the CO2 “creed”?, It´s the sun, and the seas or CR and clouds or whatever but no CO2.
My apologies for going off topic. I couldn’t locate a contact method, though I’d swear I’d seen one at some time or other.
I would like to bring your attention to a story that appeared today in The Register, Japan’s boffins: Global warming isn’t man-made; Climate science is ‘ancient astrology’, claims report.
Perhaps you, Anthony, or another knowledgeable contributor could offer a critique of the article.
cheers,
gary
The GIF is taken from the NOAA website. The front page has normal CO2 and ppm.
Its worth a visit:
http://www.esrl.noaa.gov/gmd/ccgg/globalview/
Mike
Rachel (03:22:35) is mostly right, only the remark of summer drop of d13C is reverse: the high land/vegetation in the NH gives a huge drop of total CO2 in summer, but an increase of d13C (that is a ratio, not an absolute amount), as more 12C is incorporated in vegetation growth, than 12CO2 is released by vegetation decay. In winter, vegetation decay and fossil fuel use work together and there is an increase of total CO2, but a decrease in d13C, as both vegetation decay and fossil fuel burning release a lot of 12C in ratio, compared to the atmosphere.
The SH has much more ocean than vegetation. Although there is a lot of exchange between the atmosphere and the oceans, the oceans are far more d13C neutral (slightly positive) compared to the atmosphere, thus don’t give such large variations. But in all cases, there is a clear downward trend in d13C in the atmosphere and oceans at all places:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/d13c_trends.jpg
As the trend is much smaller than the seasonal and year-by-year noise, one need over 5 years to see the trend emerge from the noise.
For the oceans, coralline sponges (here from Bermuda) incorporate a skeleton with the same d13C ratio as the surrounding seawater, here combined with the ice cores – firn – air measurements of Antarctica for about 600 years:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/sponges.gif
Rachel is correct. The stable isotopic ratio is expressed here as the ratio of the two most abundant isotopes in the carbon of the air sample (hence the delta term), as compared with an international standard. Hence, the expression in delta notation in Anthony’s figure, because:
d13C(CO2 vapour) = [[13C/12C(sample)] / [13C/12C (PDB)] -1] x 1000
The international standard that is normally used is Pee Dee Belemnite. For more information on this, see Craig (1957).
Craig, H. 1957. Isotopic standards for carbon and oxygen and correction factors for mass-spectrometric analysis of carbon dioxide. Geochim. Cosmochim. Ac. 12: 133-149.
Pee Dee Belemnite is a carbonate formation (from the Cretaceous), and this standard is defined as the 0 per mil point. The d13C composition of atmospheric CO2 is negative (-8 per mil), because it has lower 13C than the PDB standard. As plants preferentially take up the 12C, the d13C values increase in the air each summer, so the curve becomes less negative (rises), and then comes down at the times of the year when respiration and decomposition is sending the 12C enriched CO2 back into the atmosphere. Hence, the means are similar in the two hemispheres, but the hemisphere with more land (and, related to this, more seasonality) has a greater amplitude of seasonality. As more and more of our CO2 is derived from fossil fuels, the overall composition is heading downward, as pointed out by Rachel, in a distinct way compared to if the CO2 had bubbled up from the ocean. There simply is no question that the main cause of the rising CO2 concentrations in the atmosphere right now is fossil fuel burning.
As an aside, as there is more CO2 in the atmosphere, plants tend to increase their d13C values, as they are able to photosynthesize with greater water-use efficiency. This is already becoming a problematic issue for palaeoclimatologists trying to compare temperature and moisture stress today with that in the past by using the stable isotopic composition of plant material… in dry years, the plants fix more d13C, because they close their stomata and the plant is forced to take up the 13C because the 12C is already taken up. However, plants also close their stomata when there is more CO2 (why waste water if you can maintain the required intracellular CO2 concentration even with more stomata closed). So, palaeoclimatologists end up dealing with the question of whether it is really drier today, or whether the plants are just keeping more stomata closed when there is more CO2 because they can.
Rachel, a fine analysis but for one small issue:
“So, when looking at the isotopes, you see that there is a long-term downward trend in δC13, and superimposed on that is an annual cycle.”
As we’ve noted often, Spencer, here at WUWT 1/28/08, showed the 13C:12C variance under F-Test of the MLO seasonal signal and long term trend were identical.
Your surmise that the decrease in the fraction is anthropogenic may seem entirely reasonable prima facie, but it fails to be distinguishable against the vastly larger natural fluences. The logical conclusion is the natural fluxes remix the 13C:12C fraction of the ‘fossil fuel’ addition continuously.
Yes, you could still be correct, you just cannot prove it so.
Thanks to Ed for the link. I must admit, I was perplexed by the graph ordinate label, which is not defined above nor in the ESRL link. I can see from Ed Z’s link and other comments above that we’re looking at not CO2 concentration, but some function of C13 to CO2 concentrations. So why are the ordinate values negative? Here’s why: δ =
(13C/12C)sampled – (13C/12C)standard
——————————––––––––––––––– x 1.000
(13C/12C)standard
The standard refers to a carbonate rock called Pee Dee Belemnite (PDB). But you guys all knew that, right? If not, for more info, see:
http://www.ferdinand-engelbeen.be/klimaat/co2_measurements.html
It’s pretty clear from the way the annual NH value (whatever it is) wags both above and below the prevailing SH value that, over decadal (or possibly shorter) time frames, the hemispheres are well mixed. It’s a single system and ice cores would be valid measures of global CO2 trends.
Added: Note that δ from the formula in my post above is based on a multiplier of 1000. The “1.000” in the formula is the European format for “1,000” Sorry if I’ve confused anyone more than they already were.
Do algae and phytoplankton have a preference for other carbon isotopes? I believe these ocean-based plants absorb more CO2 and produce more O2 than terrestrial vegetation. Is this correct?
I was also under the impression that fossil fuels were mostly from algae, but that could be too broad a statement (or just incorrect).
Anybody know? Anybody? Bueller? Ferris Bueller?
DaveD,
You are correct. When glaciers increase in size, the expand towards the ocean. When they decrease in size, they retreat away from the ocean.
Anthony,
Is it possible to compare the seasonal variation of the northern hemisphere temperature, with the recorded changes in CO2?
An average of the period shown on a 1 year seasonal temp vs CO2.
This graph alone could help clear up the argument about what comes first, CO2 or temperature.
Ferdinand Engelbeen – you’re right, I mistyped – the 13C fraction goes up, not down, in the northern hemisphere summer.
NoAstronomer: “Over the period covered, the SOUTHERN hemisphere value actually drops from -7.8 to -8.2.” – that is due to the ongoing release of the reserve of CO2 in fossil fuels, which has a lower 13C content than the pre-existing atmospheric CO2.
gary gulrud – unfortunately Roy Spencer’s analysis didn’t show what he claimed it did. You would expect the annual variation and the long term trend to share characteristics, because they are both ultimately caused by the preferential take-up of 12C by plants. But for there to be a long term trend in δ13C in the atmosphere, there has to be CO2 going into it that has a lower 13C content than the CO2 that’s already there. This cannot be oceanic CO2, because it doesn’t have a lower 13C content.
gary gulrud (08:38:51)
However that’s a difficult argument to support in the light of the long term 13C isotope data. For example Francey et al (see below) report 13C:12C ratios (and absolute [CO2]) from the Antarctic high resolution Law-Dome cores and establish a pretty close very long term relationship relationship between the absolute CO2 concentration and the delta-13C values.
So it’s very clear that during periods (e.g. 18th century) when CO2 levels were rising very slowly indeed, that the delta-13C ratio hardly changed, and when absolute CO2 concetrations started to rise significantly and then more rapidly, the delta-13 C ratios followed:
For example:
year range //(-)delta-delta-13c (i.e. change in delta-13C)
1700-1800 //<0.3e-3 per year
1800-1850 //1.5-2.1e-3 per year
1850-1900 //3.3e-3 per year
1900-1950 //6.2e-3 per year
1950-2000 //~18e-2 per year
Clearly under conditions that there is little Nett return of carbon back into the atmosphere, there is little change in the delta-13C, value despite the very large annual growth/decay cycles dominated by the N. hemisphere terrestrial environment, and the mixing of atmospheric CO2 with surface waters. The biosphere draws down (and 13C-depletes) carbon from the atmosphere in prodigious amounts and returns this back to the atmosphere each year in the same isotopic ratio, and so in the absence of major Nett change in the amount of biomass, the contribution from the biological component of the short term carbon cycle to changes in delta-13C is small (although it can be detected on an interannual basis due to interannual changes in Nett primary productivity)
Francey RJ, Allison CE, Etheridge DM, et al. (1999)
A 1000-year high precision record of delta C-13 in atmospheric CO2 TELLUS B-Chem Phys. Meteor 51, 170-19
seems to support the ocean outgassing theory, no? warmer water can hold less CO2. this is a well established (and measurable) physical fact. it should be no surprise to learn that water in the oceans behaves in the same manner as water in a lab beaker (or soda on your counter vs in the fridge).
“Note how the southern hemisphere’s (90S to EQ)CO2C13 content remains nearly steady over the 12 year period, while the northern hemisphere shows major seasonal variation”…Translating it: NH people will be carbon taxed and SH people will receive aa lot of money for having, by far, more vegetation than the NH and so able to provide carbon shares to NH.
John Galt (09:43:49) :
Do algae and phytoplankton have a preference for other carbon isotopes? I believe these ocean-based plants absorb more CO2 and produce more O2 than terrestrial vegetation. Is this correct?
Not completely correct, But algue indeed have the same preference for 12C as land plants (photosynthesis is quite universal in that sense). If these use more CO2 and produce more O2 seems an overestimate, as much of algues is directly eaten in the food chain and only a relative small part leaves the upper oceans and drops out as organic and inorganic (shells) carbon(ate). That makes that the upper oceans have a higher d13C level than the deep oceans and the atmosphere. For a good introduction, see:
http://homepage.mac.com/uriarte/carbon13.html
Oil and gas are mostly from ocean organics, but coal is entirely from land plants…
“You all are phylum bigots!!!”
Indeed, I doubt that any of the biogenic estimates are solid because the microbiologic biomass is so poorly understood.
Even the provenance of ‘fossil fuel’ has come into question. The light crudes seem to be found in meteor-shocked sediments containing oil of microbiologic origin.
“Many soils have lost carbon over time, due to agirculture, putting most of it into the air. This alone could account for the rise of CO2 over the last few decades. Where did it go?? ”
A significant omission in our CO2 fluence models of the Carbon cycle. This reminds me of Freeman Dyson’s note that soils are the natural method sequestration of carbon. Another slam against biofuels.
A lucid and astute analysis, much obliged.
“However that’s a difficult argument to support in the light of the long term 13C isotope data. ”
Review Austin’s comments. There are some rather large loose ends to be knotted.
“expect the annual variation and the long term trend to share characteristics”
Thats ‘variance’, not variablility, not variation. That the 13C:12C fractions of the two are marching in lockstep.
morganovich: for there to be a long term trend in δ13C in the atmosphere, there has to be CO2 going into it that has a lower 13C content than the CO2 that’s already there. This cannot be oceanic CO2, because it doesn’t have a lower 13C content.
gary gulrud (08:38:51) :
Rachel, a fine analysis but for one small issue:
As we’ve noted often, Spencer, here at WUWT 1/28/08, showed the 13C:12C variance under F-Test of the MLO seasonal signal and long term trend were identical.
Yes, you could still be correct, you just cannot prove it so.
Gary, Dr. Spencer was not correct in this case, as the fossil fuel d13C signal is that strong, that it shows up in one-year changes as good as in multi-year changes. And we can prove it. Both fossil fuel burning and vegetation decay use oxygen to “burn” the carbon into CO2.
For fossil fuels we know with a resonable accuracy (from sales) how much of each type is burned. Depending of the type, the oxygen use can be calculated and the sum of all oxygen use of all fossil fuel use is known with reasonabe accuracy. Since about 1990, oxygen/nitrogen ratio in the atmosphere can be measured with sufficient accuracy to know if more or less oxygen is used than calculated.
This revealed that less oxygen is used than calculated from fossil fuel use. Thus the biosphere (land + soils + oceans) produces oxygen, thus is a net absorber for CO2 (and preferentially of 12CO2) and thus leaves more 13CO2 in the atmosphere, increasing the d13C level, while we see a decrease of the d13C level over the years. With other words, neither the (deep) oceans (too high d13C level), nor the biosphere (a net sink of CO2) are responsible for the recent increase of CO2 or the recent decrease of d13C in the atmosphere (and oceans). Only humans are to blame for the CO2 increase of the past 150 years, not the same as saying that humans are to blame for the recent warming…
@Rachel
Thank you. I saw your original post after making mine and that both removed my confusion and answered my question.
morganovich, forgive my ignorance. But doesnt the content of salt water compared to the fresher water make a difference, to the soluability. If you take pure salt water, and pure run off water. does the contaminants make a difference. Of course there is also the biological contaminants, algae, bacteria.
Some would be able to cross the salt/fresh barrier. I am a bit of a novice, it may have been said before. Does different types of sea water, from salty to fresh, absorb the same or different amounts of C02. Could other sea based life form alter that ratio of absorbtion, cold water creatures/bacteria, compared to warmer water’s.
maybe anyone can answer that question? I am genuinely curious. If it is different and since the southern hemisphers has more water mass than the north. Could that be what is skewing the scales.
NoAstronomer (07:41:02) :
Yes, exactly. That’s an indication of the effect of Nett return of 13C-depleted carbon back into the atmosphere. As we oxidise fossil fuels (long-sequestered 13C-depeleted carbon) and return these back to the atmosphere, so the delta-13c value gets increasingly negative (the absolute value gets larger).
We can get an indication of the scale of these changes and their timescales from analysis of relatively high resolution ice-core data [***].
For example:
the delta 13C level was -6.44 in 1006 AD, and -6.49 in 1825. In 1869 it was still -6.46.
combining ice core data and contemporaneous atmospheric measurements:
year //delta 13C%
1845 //-6.40
1854 //-6.45
1898 //-6.55
1905 //-6.65
1948 //-6.90
1948 //-6.88
(1978 //-7.37) Cape Grim Air Archive
(1996 //-7.83) ” ” ”
and now we’re at around -8.2 as you say
Francey RJ, Allison CE, Etheridge DM, et al. (1999)
A 1000-year high precision record of delta C-13 in atmospheric CO2 TELLUS B-Chem Phys. Meteor 51, 170-19
Rachel says:
Another reason that Spencer’s analysis is not correct is that he made a huge blunder. The two different plots that he produced are really mathematically constrained to give identical results…So, what he claimed was a significant finding had no physical meaning whatsoever. See here for more discussion: http://tamino.wordpress.com/2009/01/19/a-bag-of-hammers/ Even if one does not personally like tamino (as I know many here do not), it is easy enough to verify what he says as long as you know basic calculus. Besides which, the fact that both of Spencer’s plot gave identical slopes and R^2 ought to have been a dead giveaway that something was amiss. With real experimental data, one would almost never expect such perfect agreement unless there was a reason, which in this case is that the mathematics requires it because the two graphs are really just plotting the same thing up to some constant offset.
“Gary, Dr. Spencer was not correct in this case”
I’m sorry Ferdinand, try as I might your posts never seem to address the point. Perhaps this is my fault, perhaps it is a cultural thing. I suggest you start with the F-Test and see if I have missed something there.
“”” Joel Shore (07:13:22) :
R Stevenson says:
Any global warming caused by 350ppm CO2 in the air pales into insignificance compared with that produced by moisture. Yet even Al Gore et al does not refer to moisture as a GHG.
Water vapor is a greenhouse gas. However, it is not one that we can currently affect the concentration of through emissions of water vapor because of its higher concentration and shorter residence time in the atmosphere and the great availability of water in the liquid form to be evaporated. The way we can change the amount of water vapor in the atmosphere is by causing warming by increasing CO2 concentrations which then causes the amount of water vapor in the atmosphere to increase. And, indeed this feedback due to water vapor causes an increase in the warming effect due to forcings such as increases in CO2.
This is often summarized by saying that water vapor is a feedback, not a forcing.
Joel; have you re-read what you just said in response to R Stevenson ??
“shorter residence time in the atmosphere ”
Just where exactly did you learn that water has a short residence time in the atmosphere; water is a PERMANENT resident of the atmosphere; it has a near infinite residence time in the atmosphere; in human lifespan terms.
Do you honestly think that a solar spectrum or earth thermal photon gives a hoot about which water molecule in the atmopshere absorbs it; they can’t distinguish on ewater molecule form another; and neither can you (other than isotopic species of water).
This farce that water vapor is NOT a greenhouse gas that can initiate warming; but is a FEEDBACK; is utter rubbish.
Water molecules (any one of any kind) can absorb elecromagnetic radiation photons, either in the 5-20 thermal IR band; or in the 0.75-5 solar spectrum band, just as easily as any other GHG including CO2. In fact water absorbs over a much greater range of wavenlenghts than the rest of them combined. CO2 has almost zero solar spectrum absorption compared to water, and the long wave water absorption exceeds that of any other known liquid.
GHG molecules act as individual molecules; they don’t even know there is another like them in the whole universe. At 385 ppm, a CO2 molecule is one of 2597 molecules, and its nearest neighbor CO2 is 14 molecules distant in any direction. The next thing that happens to ANY GHG molecule, either water or CO2, is that it immediately collides with the normal atmospheric gases of Nirogen, Oqygen and Argon, and that energy from the absorbed photon becomes energy of thermal agitation of the ordinary air molecules. Only at extreme altitudes would any GHG molecule have a long enough mean free path to re-emit the photon it absorbed out of the thermal IR or solar spectrum; at lower altitudes the energy becomes thermalized in the normal atmospheric gases.
The source of the thermal back radiation from the atmosphere certainly is not any CO2 or water molecule; it is the ordinary atmospheric gases that emit the atmosphere’s thermal radiation; part of which can then warm the surface. And the surface (mostly is water) which absorbs ALL of that long wave radiation in less than ten microns; which leads to prompt evaporation of more water vapor.
The surface has no clue whatsoever which kind of GHGmolecule captured the energy that resulted in the backthermal radiation that warmed the surface and led to further evaporation.
Water vapor has absolutely no need whatsoever of any “trigger” event caused by CO2 or ozone or any other GHG species, in order to cause more evaporation; it is perfectly capable of doing that on its own.
The ONLY thing that matters in “GHG” capture of radiation to warm the atmopshere, is the TOTAL number of GHG molecules of all species; and water far and away exceeds the total of all the others; and then in addition it absorbs far more energy (at least 22% of incoming solar), and more thermal IR than all the other GHGspecies combined.
The biggest failing of climate science is their refusal to acknowledge that water is a permanent resident greenhouse gas in the atmosphere; that can cause all the atmospheric and surface warming we need; and then it pays us back by forming clouds out of its liquid and solid phases; that no other GHG can do; and which produces a compensating NEGATIVE FEEDBACK cooling effect to balance the water vapor warming.
And that in a nutshell, is why it doesn’t matter a darn what species of carbon is in circulation or where it comes from or how long it lasts in the atmopshere,because it has almost nothing to do with the end result.
It’s the WATER.
oops, you’ve already had your question addressed, NoAstronomer. My last post is a supplement!
CARBON IS THE WORLD’S BEST FRIEND
By David Bellamy and Jack Barrett
History has it that an apple fell on Isaac Newton’s head allowing him to realise why, “what goes up must come down” and go on to formulate the basic laws of physics. Revisiting those laws in the infrared glow of the global-warming debate forces the realisation that when it comes to radiant heat, “what comes down must go up” — for if it didn’t, the Earth would overheat.
Some 50 years after the end of the Little ice age, in a time we now call the pre- industrial age, the world appeared to be well content with an atmosphere containing 285 ppmv of CO2 and the average amount of water vapour.
Since 1992 we have had a special UN-supported Intergovernmental Panel on Climate Change warning the world that we are heading for real trouble, if the concentration of carbon dioxide, one of the five so called greenhouse gases in the atmosphere doubles its pre-industrial value.
Here are ten, let us call them Newton’s Apples, that sow real seeds of doubt about the science behind the IPCC’s conclusions.
(1) Measurements prove that the pre-industrial damp blanket trapped 94.7% of all the infrared radiation as it escaped into space leaving a mere 5.3% to warm the great interstellar sink directly. All this thanks to the fact that the spectral escape window was partially blocked by what we now call the greenhouse gases that kept the Earth warm.
(2) If we took no notice of the IPCC’s warnings and burned all the known reserves of natural gas, the concentration of carbon dioxide in the atmosphere would rise to 454 ppmv.
(3) Now throw caution to the wind and burn all the oil reserves we know about — and the CO2 concentration would go up to 489 ppmv. Still nowhere near the dreaded doubled value of those “halcyon” pre industrial days.
(4) So let’s pull out all the stops and burn at least one-third of coal reserves in all its forms. With an awful lot of mining we would make the now much-feared figure of 570 ppmv. A point, at which IPCC’s super computer models warn that the sky might soon come falling down.
They rarely mention the fact that around 600 million tonnes of extra potential plant fertilizer and about 1 billion tonnes of extra irrigation water hanging about up there, continue to help balance the biosphere while increasing the atmospheric pressure by a mere 0.3 millibars.
The atmospheric blanket would now trap 95.6% of the infrared radiation (a mere increase of 0.9% over those pre-industrial days) and the potential absorption by the combination of water vapour and CO2 is almost complete — thanks to the logarithmic relationship between concentration and radiance/absorption.
(5) Simple arithmetic also proves that at this moment of time in the IPCC’s countdown to catastrophe the annual increase of CO2 pouring into the atmosphere is a mere 3% of the natural turnover of this very important gas in the atmosphere. Thus leaving little doubt that there is massive buffering capacity in the system.
(6) A smidgen of maths proves that all the much “feared” doubling of the concentration of CO2 in the atmosphere actually accomplishes is a slight narrowing of the infrared ‘window’ through which radiation escapes to space.
(7) Checking the spectra also shows there is a window in that infrared escape route that can never be closed because there are no natural gases with the right spectral bands. If there were the temperature might then go up by around 5 degrees Celsius.
(8) Measurements also show that the infrared absorption spectra of all the greenhouse gases overlap to a certain extent; in consequence, their cumulative effect can never be realized. A cumulative effect that is already nearing saturation when no further heat will be trapped, thanks to the fact that the relationship between the concentration of any of the greenhouse gases and radiance/absorption is logarithmic.
(9) Despite all this incontrovertible evidence that the increase of the concentration of carbon dioxide in the atmosphere is a benign and almost spent force, the global warmers beg to differ. Their conclusion, drawn from a plethora of complex computer models, leads them to warn the World that an increase in trapped radiation of only 0.9% might trigger a catastrophic course of events. A chain reaction that could be responsible for a runaway enhancement of global warming that could pose a threat to much more than our way of life. To give their argument teeth, they appear to put all their eggs into the basket of what they call radiative forcing, building into their models only positive feedbacks related to water vapour that trap more heat.
(10) Newton’s Law of Cooling perhaps drops the largest apple on the head of the IPCC’s arguments of a melt down scenario. In the simplest of terms, it proves that if the non-radiative properties of water (evaporation, albedo, mass transfer etc.,) were not already at work at the earth/ atmosphere interface, the Earth’s surface would be some 13°C warmer. So again there is a lot of negative feedback in the system.
The global warmers can hypothesise as much as they like about the cause and effect of trapping the last few percent of the available infrared radiance by the greenhouse gases, but without admitting that there is another source of heat at play in the system their scare mongering is no more than hot air.
Take heart all those super climate modellers: There is still a lot of work for your giant computers to get stuck into. Take a few gigabytes out of Newton’s Apples and get cracking solving the real problems that face over 6.4 billion human beings as they move into an uncertain energy-hungry future.
Please remember that the main reasons for soil erosion, salination, floods, droughts, famines, the collapse of coral reefs and the extinction of species are habitat destruction, overgrazing and over-fishing — not a 0.9 % rise in trapped radiance.
Carbon dioxide is not the dreaded greenhouse gas that the global warmers crack it up to be. It is in fact the most important airborne fertiliser in the world and without it there would be no green plants at all. In fact, a doubling of the levels of this gas in the atmosphere would bring about a marked rise in plant production — good news for everyone, especially those malnourished millions who can’t afford chemical fertilisers. Perhaps the time is ripe to really start worrying (again) about the fact that for the last 200 million years the concentration of carbon dioxide in our atmosphere has been falling. Indeed it dropped to dangerously low levels during recent ice ages. The Plant Kingdom responded to this potentially catastrophic (no carbon no food) situation by producing the so-called C4 plants that can survive low CO2 by using sunlight more efficiently.
Please talk to your plants — and as you do, rest assured that they in effect will thank you, by recycling your waste carbon dioxide to make more plant material and return oxygen to the earth’s atmosphere.
——————-
Dr David Bellamy OBE. Plant Ecologist, Author, Writer and presenter of TV documentaries for BBC and ITV, International campaigner for the rational use of the resources of the biosphere.
Jack Barrett, PhD (Physical chemistry, Imperial College, London)
What are the C and O isotopic ratios of the water comets impacting the upper atmosphere? Does this change over time and in response to solar issues?
http://smallcomets.physics.uiowa.edu/
“At a rate of one 20-to-40 ton comet every three seconds, this influx of small comets into the atmosphere would add about one inch of water to the Earth’s surface every 20,000 years or so. The implications of this added water for long range global climate, global warming, and pollution mitigation will need to be examined by the experts in those fields.”
George E. Smith (11:59:18) :
Careful George,
Your very long post is a point-misser. Joel’s stating a truism. Water vapour has a very short residence time, and an atmospheric partitioning that is effectively dfined by the atmospheric temperature and pressure. The consequence is that as the atmospheric conditions vary (change in pressure, but more pertinent, change in temperature) the water vapour content follows rather faithfully. So the variation in atmospheric water vapour content is always a feedback (a response) to whatever forcing (negative or positive) caused the change in temperature.
Water vapour is a “permanent resident greenhouse gas” (in your parlance), but it’s levels are effectively “set” by the atmospheric temperature and pressure. We can assess this in the real world, and don’t need to pretend that it’s not true.
We can spray water (or steam if you prefer) into the atmosphere to our hearts content…it falls right back out again, because the atmosphere at whatever particular temperature and pressure can only retain so much water vapour. Pump CO2 into the atmosphere and it stays there (that proportion that doesn’t partition into the oceans and a wee bit into the terrestrial environment) for a rather long time.
It’s worth poiniting out that a significant part of any CO2-induced warming is the result of the water-vapour feedback. In other words while on a molecule for molecule basis water vapour is more effective as a greenhouse gas than CO2, a significant part of the water vapour greenhouse contribution is actually ultimately a CO2 (and methane and ozone and nitrous oxide and chlorofluorocarbon) contribution.
“This farce that water vapor is NOT a greenhouse gas that can initiate warming; but is a FEEDBACK; is utter rubbish.”
Now that is what we term “Nailing it”.
http://en.wikipedia.org/wiki/Antarctic_krill
“There is speculation that this process is one of the largest biofeedback mechanisms of the planet, maybe the most sizable of all, driven by a gigantic biomass. Still more research is needed to quantify the Southern Ocean ecosystem.”
“Pump CO2 into the atmosphere and it stays there (that proportion that doesn’t partition into the oceans and a wee bit into the terrestrial environment) for a rather long time.”
Pure fantasy. Radiogenic 14C, created at the poles high in the Stratosphere has a lifetime of 60 years. The AIRS data clearly shows the poorly mixed nature of CO2 and its association with convected H2O.
Michael D Smith (07:41:50) :
In case anyone was wondering:
δ13C = [ (13C/12C) sample / (13C/12C) reference – 1 ] x 1000
reference samples are also discussed here:http://www.esrl.noaa.gov/gmd/ccgg/globalview/co2c13/co2c13_method.html
I still don’t see what the reference represents (reference is “normal” compared to what and how that applies to historical records), so if anyone has any insight I’d appreciate it…
From the paper:
Background parameter values and dynamical model
In this work similar to Peters et al [12], the dynamical model is applied to the mean parameter values as:
bt
= (at
−2 + at
−1 + p)/3.0 (1)
Where superscript a refers to analyzed quantities from previous steps, superscript b refers to the background values for the new step, and superscript p refers to real a-priori determined values that are fixed in time and chosen as part of the inversion set-up. Physically, this model describes
that parameter values for a new time step are chosen as a combination between optimized values from the two previous time steps, and a fixed prior value. This operation is similar to the simple persistence forecast used previously [12], but represents a smoothing over three time steps thus
dampening variations in the forecast of b in time. The inclusion of the prior term p acts as a regularization [14] and ensures that the parameters in our system will eventually revert back to predetermined prior values when there is no information coming from the observations. Note that
our dynamical model equation does not include an error term on the dynamical model, for the simple reason that we don’t know the error of this model. This is reflected in the treatment of covariance, which is always set to a prior covariance structure and not forecasted with our dynamical model. Our choice to use a combination of 3 states is a compromise between prescribing prior fluxes at each step and letting the system propagate all information from one step to the next without
any guidance. Although the latter will work fine for the North American fluxes which are strongly constrained by observations, fluxes in most of the rest of the world need the regularization to stay within reasonable bounds in the absence of observational information and a proper dynamical model for CO2 fluxes. The posterior covariance can be used to diagnose areas where minimal observational constraints necessitate the use of the prior term. We furthermore note that the described dynamical model imposes a smoothness on the estimated state vectors similar to a prior temporal covariance structure, which we do not specify in our system.
What does the above remind you of? E.M Smith….Where are you? E.M……We need some help working on the cooked books.
” Even if one does not personally like tamino (as I know many here do not), it is easy enough to verify what he says as long as you know basic calculus.”
Ok Joel, I promise to get around to this over the next week or so. But ‘dislike’ is rather patronizing, I find him/her utterly, pathetically clueless on every issue I’ve followed up.
If you’ve sent me on another such mission I will not be happy.
For all those people who worry about methane….? Don’t.
http://petesplace-peter.blogspot.com/2009/02/leaking-methane-gas-from-seafloor.html
George E. Smith: I suggest carefully reading what other people say before going off on long tirades. I don’t disagree that water vapor is a greenhouse gas. My point (as foinavon has re-iterated in more detail) is simply that we cannot directly change its concentration … at least unless our emissions of water vapor increase by several orders of magnitude form what they are now.
The reason water vapor that is considered a feedback is that its concentration in the atmosphere does change when the temperature changes…and hence, since it is a greenhouse gas, this provides a feedback effect on whatever initiated the warming.
Note that there are no claims in my discussion that water vapor is incapable of absorbing IR all on its own. It is simply a question of what determines the level of water vapor in the atmosphere.
“”” foinavon (13:00:34) :
George E. Smith (11:59:18) :
Careful George,
Your very long post is a point-misser. Joel’s stating a truism. Water vapour has a very short residence time, and an atmospheric partitioning that is effectively dfined by the atmospheric temperature and pressure. “””
So I’ll take your word for it foinavon; water has a very short residnece time.
Can you point me to a peer reviewed scientific paper that presents data concenring the MOST RECENT occurrence of the absence of water vapor from earth’s atmosphere; I don’t need a dozen or so instances; just one will do; and cancel that most recent; tell me about the time you most remember when the earth’s atmosphere was devoid of water vapor; I’ll accept anything less than 280 ppm (molecular species) of water vapor averaged over the whole globe; and I’ll even accept a time as short as 24 hours for the atmsopheric water vapor to remain that low.
Otherwise quit pulling our legs; water vapor is a permanent fixture in earth’s atmosphere.
The saturated vapor pressure of water at 15 deg C (the fictional global mean temperature) is 0.0168 atmospheres. at 60% relative humidty on average that is 1% of the atmosphere. At 30 deg C (86F) which might be more typicalover tropical oceans; the saturated water vapor pressure is 31.71 mm Hg which is about 4.2%and the tropical ocean humidity isn’t too likely to be as low as 25% which wopuld still keep water vapor above 1%.
Gimme a call whaen water vapor unresides down to 280 ppm world wide; hell I’ll even accept 0.1%. As I said it is total nonsense; If more PhD “Climatologists” were actually Physicists, instead of statistical mathematicians; that would be self evident to them that water is permanent in the atmosphere for all practical purposes.
George
It is a little curious the northern hemisphere seasonal signal varies more as you go north whereas one would expect the max seasonal signal to be in the mid-northern-latitudes (where there is greater growth and die-off of plants with the season). But the signal seems to vary more as you go progressively farther north.
I found the study below, which shows that a northern boreal swamp (most northern forests are swampy) in Manitoba is a net carbon source (by quite a large amount) even though they only measured the carbon flux for 4 months of the year, including all of the growing season.
This indicates,
1. A substantial proportion of the seasonal CO2 increase comes from northern hemisphere natural CO2 sources rather human emissions.
2. These areas were substantially warmer is the fairly recent past (last 1,000 years) with a much longer growing season which allowed net carbon dioxide capture forming a carbon store for the current net carbon dioxide release.
http://cat.inist.fr/?aModele=afficheN&cpsidt=2152683
Hug & Barrett versus IPCC
by
Heinz Hug and Jack Barrett
http://www.john-daly.com/forcing/hug-barrett.htm
The IPCC mechanism for global warming relies entirely upon the theory of radiative transfer. This assumes a long-term radiative equilibrium for the interaction between incoming solar radiation and out-going long wavelength radiation. The theory is correct for ‘blue skies’ and has to be severely modified to take into account the effects of clouds and the transfer of energy by non-radiative processes to the troposphere of latent heat of evaporation of water. In particular, the IPCC mechanism is based on the re-emission of absorbed terrestrial radiation, some of which is directed downwards and causes the extra warming of the Earth’s surface.
The mechanism of global warming must be defined in a better manner so that all relevant processes are represented.
It must be recognized that Kirchhoff’s law applies only to systems in thermal equilibrium.
The proper effects of line broadening must be recognized. That line broadening occurs at all indicates that collisional processes are important.
The value of the atmospheric sensitivity given by the IPCC seems to be too large. If the IPCC value for atmospheric sensitivity is exaggerated by a factor of about four, the predicted increase in temperature for a doubling of carbon dioxide will be too small to be discernible against the background of natural variability of the climate.
The ignoring of the spectral effects of water vapour seems to be the reason for the exaggeration of the sensitivity.
The failure of models to settle the sign of the water vapour feedback induces doubts about the whole process of modelling at the present time.
The concept of local thermodynamic equilibrium is given different interpretations and leads to errors in applications of theory to the atmospheric problem.
The kinetics of the carbon cycle needs further consideration. If the CO2 content of the atmosphere is not going to reach double that of the pre-industrial era, the whole of the IPCC approach to future climate change is in doubt.
gary gulrud (10:43:37) :
Not really Gary. The soils and their organic content are part of the terrestrial biosphere and their contributions are subject to the same analysis that applies to absolute CO2 concentrations and relative 13C:12C content in relation to the flux through the biosphere that we’ve already discussed. The bottom line is that the atmospheric 13C ratios were essentially flat in the 800-odd years before the mid 19th century and have decreased pretty faithfully as absolute atmospheric CO2 levels have risen in line with our emissions [see data in foinavon (10:07:56) and foinavon (11:50:41)].
I agree with Austin that we should address the impoverishment of agricultural soils, since the present means of industrial farming in which soils are virtually “sterilized” and then made useable by additions of large amounts of fertilizers is not sustainable in the long term. Likewise, land use changes (largely deforestation) have contributed somewhatto the enhanced CO2 concentrations.
I don’t agree with Austin that the biosphere of the Earth has been running down over time due to a decreasing rate of carbon emissions from bacteria and volcanoes. Atmospheric CO2 levels have been pretty constant (apart from reductions during ice age glacials) for the last 10 million years or so, for example, and the biosphere is rather well adapted to the extant levels of CO2 during that long period. [Apologies to Austin btw for addressing his post in the third person.]
gary gulrud (13:13:40) :
Gary, are you being seduced by the capital letters? Not even capital letters make an incorrect assertion true! We can observe from real world measurements the warming-induced enhancement of water vapour in the atmosphere, its rapid fall in response to cooling from volcanic eruptions, its temporal variation due to stochastic variations in atmospheric temperature and so on [***].
gary gulrud (13:21:22) :
I suspect you’re describing the time constant for the flux of 14C CO2 molecules through the biosphere and with the ocean surface. However if you link or cite your source we can assess this. One reason why I suspect your 14C argument is misplaced relates to the nuclear testing of the mid 20th century which significantly raised atmospheric 14CO2 levels. However these have decreased during the last half-decade or so, while absolute CO2 levels have risen. In other words we have to be careful to distinguish fluxes (within dynamic equilibria for example), and the absolute concentrations within each compartment, of the molecules of interest.
In short, CO2 levels are defined by equilibrium partitioning between atmosphere and oceans (and land somewhat), and while a significant proportion of our CO2 emissions are rapidly absorbed by the surface layers of the oceans, complete equilibration occurs on a very long time scale (many hundreds if not thousands of years). However individual molecules are in exchange with the various carbon sinks on a relatively rapid timescale. Therefore levels of identifiable trace elements (like 14C in CO2) introduced in a “pulse” (mid 20th century nuclear tests) can fall in atmospheric concentration even as Nett atmospheric CO2 concentrations rise…we can measure this easily in the real world.
Water vapour is a different kettle of fish. While the atmosphere can support essentially unlimited CO2 concentrations, water vapour has a potential atmospheric concentration that is limited by the atmospheric pressure and temperature. Both models and real world measurements [***] support the conclusion that water vapour tends to maintain, on average, a roughly constant relative humidity such that as the atmosphere warms, the absolute water vapour content rises and as the atmosphere cools, the absolute water vapour content drops. However one cannot “make the atmosphere warm” by pumping water vapour into it!
[***] e.g.
Soden BJ, et al (2005) The radiative signature of upper tropospheric moistening Science 310, 841-844
Santer BD et al. (2007) Identification of human-induced changes in atmospheric moisture content. Proc. Natl. Acad. Sci. USA 104, 15248-15253
Brogniez H and Pierrehumbert RT (2007) Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data. Geophys. Res. Lett. 34, art #L17912
Buehler SA (2008) An upper tropospheric humidity data set from operational satellite microwave data. J. Geophys. Res. 113, art #D14110
Gettelman A and Fu, Q. (2008) Observed and simulated upper-tropospheric water vapor feedback . J. Climate 21, 3282-3289
and so on. There’s lots of real world analysis of this basic point…
“”” foinavon (13:00:34) :
George E. Smith (11:59:18) :
Careful George,
Water vapour is a “permanent resident greenhouse gas” (in your parlance), but it’s levels are effectively “set” by the atmospheric temperature and pressure. We can assess this in the real world, and don’t need to pretend that it’s not true.
We can spray water (or steam if you prefer) into the atmosphere to our hearts content…it falls right back out again, because the atmosphere at whatever particular temperature and pressure can only retain so much water vapour. “””
Well foinavon whether or not water evaporates from oceans or any other water body, including the surface moisture in the soil; has absolutely nothing whatsoever to do with either the atmospheric temperature; nor with it’s pressure. It is SOLELY a function of the surface temperature OF THE WATER.
And whether it STAYS IN THE ATMOSPHERE or “falls right back out” is solely a function of the partial pressure of the water vapor in the atmosphere and the temperature (of that water vapor) in the atmosphere. The only way that air pressure and temperature and temperature affect that is that air pressure (totla) will determine the mean free path between collisions; and air temperature will determine the mean time between collisions; which together; yes will affect the temperature of the water vapor, which ultimately will try to equilibrate with the atmospheric main gases.
BUT; even after all your falling back out, and atmospheric presure and temperature limitations on water vapor content; water STILL remains in the atmosphere in quantities which swamp ALL other GHG molecules put together.
And as I explained, the thermal radiation in the long-wave IR, which lands back on the surface (to warm it) or is re-absorbed by the atmosphere in some way (to warm it), carries ZERO information as to which molecular species originally captured a solar of thermal radiation photon whose energy is ultimately transferred to the atmosphere as molecular kinetic energy.
So there is no possible way that surface evaporation processes can tell what triggered them, since the downward thermal radiation comes from the ordinary atmospheric gases, and NOT from any GHG molecule.
But hey foinavon; I’m not here to convince you; or for that matter anyone else; I don’t really care what anyone else believes. If you are happy to hang your career hat, or your scientific reputation, oin a belief that water is NOT a GHG, but a CO2 feedback mechanism; be my guest.
By the way; I’m an old (very old) Analog circuit designer, from since the days when transistors were “valves” or “vaccuum tubes” up to when they are CMOS microcircuits, in all their analog forms (try hiring any Analog IC circuit designer).
So if there is one thing that I understand right in my genes; it is FEEDBACK; and feedback always involves propagation delays; which result in phase shifts between input signals, and fed back output signals; and with any appreciable amount of phase shift, and loop gain; the whole thing will oscillate.
So perhaps you can cite for us a peer reviewed scientific climate paper in which GHG feedback oscillations were observed; even in the case of AL Gore’s 800 year feedback delay from warming to CO2 increases;
The other sort of paper that would be interesting, would be a climate model (GCM) paper; like Peter Humbug churns out with his Playstation vide game; in which the time response of his feedback circuit is modelled and described in detail; not the fictitious static model that ignores time; but the one that includes the frequency response or impulse response of the climate model.
Once again, I only need one example of each; not a whole avalanche of papers.
George
“”” Joel Shore (14:34:47) :
George E. Smith: I suggest carefully reading what other people say before going off on long tirades. I don’t disagree that water vapor is a greenhouse gas. My point (as foinavon has re-iterated in more detail) is simply that we cannot directly change its concentration … at least unless our emissions of water vapor increase by several orders of magnitude form what they are now. “””
Oh forgive me; now I get it; the reason why climatologists ignore water vapor greenhouse effect, is that they can’t hang the problem on us humans; we don’t control it, so they can’t use it to hammer us into meekly accepting their Leftist behavioral control of our lives; If man isn’t causing disastrous climate chage the greens can’t force us into accepting their utopian authoritrian future.
Which is not to say that all climatologists are leftists; just the political opportunists who sieze on their work to further their new world order.
My apologies Joel and Foinavon; so I understand that until we move to the new Hydrogen economy and get rid of the evil carbon; we will not be putting enough of man made water vapor GHG into the atmosphere to matter; got it! Hurricanes alone don’t do the job of putting enough water vapor in the atmospehre; we need our Hydrogen Humvees courtesy of Girly Man Schwarzenegger to get us to the point where water vapor becomes a proble.
George E. Smith – a short residence time does not mean that at some recent time there was no water vapour in the atmosphere. Imagine a pipe with water flowing through it. The residence time in the pipe for a given molecule of water is obviously short, but equally obviously this doesn’t mean the pipe must have been empty recently.
Scientist Tells Congress: Earth in ‘CO2 Famine’
No cause for alarm
http://epw.senate.gov/public/index.cfm?FuseAction=Minority.Blogs&ContentRecord_id=af8f5b20-802a-23ad-49fb-8a2d53f00437
“”” Ed Scott (14:47:16) :
Hug & Barrett versus IPCC
by
Heinz Hug and Jack Barrett “””
Hey Ed,
I read another paper by Heinz Hug, relating to the absorption spectrum of CO2; mainly the 15 micron band. I’m not sure I digested it properly as he came up with some exteemely small effects; but basically he made lab measurements with ain IR spectrometer.
He dsecribed his methodology, as creating a pure purely synthetic “air” sample, presumably out of N2, O2, and Ar; no idea what he did about isotopic abundances if anything; and then he carefully injected 350 something ppm of CO2 (whatever the value was when he did this some years ago, plus he added 2.6% of water vapor; and then he proceeded to scan the ir spectrum from a Globar source.
Now what I can’t figure out is why if you wanted to know the accurate experimental infrared absorption spectrum of CO2 in air at about the current abundance; would you add 2.6% of water vapoir, which can only muddy the situation since water absorbs in the same ranges as CO2 does, and more.
Why wouldn’t he use a pure dry synthetic atmosphere with no doping species besides the CO2 ?
Got any ideas ?
George
“”” Rachel (15:42:28) :
George E. Smith – a short residence time does not mean that at some recent time there was no water vapour in the atmosphere. Imagine a pipe with water flowing through it. The residence time in the pipe for a given molecule of water is obviously short, but equally obviously this doesn’t mean the pipe must have been empty recently. “””
Rachel, you are absolutely correct; but for the record, the earth emitted thermal EM radiation could care less whether the water molecule that captured one of its photons, has been in the atmosphere for a week or whether it arrived there one nanosecond ago.
Why is it that so many people today are unable to separate the significant variable in a problem from inconsequential side details that don’t relate to the problem.
What matters in evaluating the GHG absorption of earth thermal IR radiation; or for that matter incoming solar radiation, is how much GHG is in the atmosphere at the time the radiation arrives. It matters not a jot, if that GHG disappears a millisecond later to be replaced by a different GHG molecule that was in the ocen or ground before or some tree. ONLY the amount in the atmosphere at the time the radiation is there to be intercepted matters. The interception process has only one requirement; the intercepting GHG molecule, and the EM radiation photon must both be present simultaneoulsly, and the photon has to intersect the capture crossection for that absorption process, of that molecule. How long that particular molecule exists in the atmosphere after capture is totally irrelevent; so long as it perists for at least the mean time between molecular collisions so it can transfer the energy to the air molecules as kinetic energy of molecular motion.
Is this the result of the modern education “group therapy” where students “co-operate” on solving a problem so that most of them never learn the elements of problem solving, because someone in the group did it all for them, and they just wrote it up in their own words; even thought they still had no idea why it was so.
The “Residence time” that much vaunted property of CO2 that takes it 200-1000 years to vamoose; even though the natural annual cylce easily removes 18 ppm in as short as 4 months at the north pole, and 6 ppm at Mauna Loa; is a mythology to promulgate the notion that somehow CO2 that results from human activities (including exhaling) last forever and causes global warming, whereas good clean natural CO2 that escaped from the ocean or some Aspidistra, goes away in four months, but doesn’t cause global warming anyway; because it is good clean natural carbon.
If you read the report to the Congress that Dr Happer gave today, as mentioned above; you will see that he reported that we presently enjoy; or perhaps are plagued by; the lowest atmospheric CO2 levels that the earth has had in the last 600 million years; during which time life on earth flourished. Historically the levels have been upwards of 7000 ppm and it did not exterminate all life on this planet, as Hansen seems to suggest along with Al Gore, is going to happen when we hit 500 ppm.
Ain’t gonna happen; so get over it.
George E Smith:
I am not able to carry the burden of these arguments, but I can point to relevant material.
You, and perhaps others on this thread, will be interested in this article by Jeffrey A. Glassman, “On Why Co2 Is Known Not To Have Accumulated In The Atmosphere & What Is Happening With Co2 In The Modern Era,” http://www.rocketscientistsjournal.com/2007/06/on_why_co2_is_known_not_to_hav.html#more.
In this article Dr. Glassman states, inter alia, that in view of the rates of emission and absorption of atmospheric CO2 relative to the total amount of atmospheric CO2, “Regardless of which way one poses the problem, the existing CO2 in the atmosphere has a mean residence time of 1.5 years using IPCC data, 3.2 years using University of Colorado data, or 4.9 years using Texas A&M data. The half lives are 0.65 years, 1.83 years, and 3.0 years, respectively. This is not “decades to centuries” as proclaimed by the Consensus. Climate Change 2001, Technical Summary of the Working Group I Report, p. 25.”
You might also find interesting his paper “The Acquittal of Carbon Dioxide”, http://www.rocketscientistsjournal.com/2006/10/co2_acquittal.html#more. From the abstract:
“Throughout the past 420 millennia, comprising four interglacial periods, the Vostok record of atmospheric carbon dioxide concentration is imprinted with, and fully characterized by, the physics of the solubility of CO2 in water, along with the lag in the deep ocean circulation. Notwithstanding that carbon dioxide is a greenhouse gas, atmospheric carbon dioxide has neither caused nor amplified global temperature increases. Increased carbon dioxide has been an effect of global warming, not a cause. Technically, carbon dioxide is a lagging proxy for ocean temperatures. When global temperature, and along with it, ocean temperature rises, the physics of solubility causes atmospheric CO2 to increase. If increases in carbon dioxide, or any other greenhouse gas, could have in turn raised global temperatures, the positive feedback would have been catastrophic. While the conditions for such a catastrophe were present in the Vostok record from natural causes, the runaway event did not occur. Carbon dioxide does not accumulate in the atmosphere.”
Best regards,
George E. Smith says:
They don’t ignore water vapor. They just don’t see a mechanism by which water vapor concentration in the atmosphere will spontaneously change and produce dramatic climate change on its own. Do you know of such a mechanism?
The fact is that humans are dramatically changing the levels on CO2 on a timescale that is very rapid geologically speaking. It is not a “Leftist” plot to be concerned about the consequences of this. It is simply a combination of science and common sense.
Tim Clark (13:33:44) :
Hmm… I didn’t even see Steig and Mann in the references! I guess I missed that.
It is often useful to use similar procedures to simplify the underlying equations, I find this one particularly insightful when trying to explain difficult concepts:
http://rigo.altervista.org/papers/engineering_procedure.pdf
Well said Geroge, climatologists need to understand the water cycle more than the carbon cycle.
“They don’t ignore water vapor. They just don’t see a mechanism by which water vapor concentration in the atmosphere will spontaneously change and produce dramatic climate change on its own. Do you know of such a mechanism?”
Where is the evidence that CO2 is drmatically changing climate? Katrina? Australian bush fires?
George E. Smith (16:52:53) :
Why do you find dew on the grass on summer mornings?
I think that demonstrates that water vapor concentrations are a feedback to atmospheric temperatures (even though water vapor is a GHG).
WRT to your statements about the short residence times of CO2- those numbers (a few years) refer to individual CO2 molecules, not the CO2 concentrations in the atmosphere.
Fill a jar halfway up with Coke, and then seal it. Some of the CO2 in the coke will bubble up into the air above, until it reaches a certain concentration, x ppm. That concentration will be a function of the temperature and pressure. There will still be some CO2 dissolved in the Coke.
But at that concentration (x ppm), all the CO2 molecules in the air space don’t stop bouncing around and just sit in the air- some of them bounce back into solution in the Coke. But at the same time, the same number of CO2 molecules are bouncing out of the Coke and into the air space. The number of CO2 molecules moving into and out of the Coke are at equilibrium.
The lifetime of a CO2 molecule in the airspace above the Coke is finite- at some point, every CO2 molecule in the air space will bounce back into the Coke, and replaced by another bouncing out of the Coke. The average time it takes for a CO2 molecule to do that is the “lifetime” of an individual CO2 molecule.
But the CONCENTRATION of CO2 in the air space above the Coke doesn’t change. If the jar is perfectly sealed, the lifetime of x ppm in the air space is …forever.
That is why the lifetime of an individual CO2 molecule in the atmosphere tells you nothing about how long a certain concentration of CO2 remains in the atmosphere.
Sorry for the long post, but I’ve seen this point come up so many times….
Scientists might not know how water vapor can produce dramatic change, but real scientists know that there are many things they don’t know about weather and climate. Such as cloud behavior being poorly understood. Could summer thunderstorms become the dominant cloud type, with scattered towering clouds each evening which had allowed most of the surface to stay in sunlight during the day, yet collapsing in time for morning to have clear skies to warm the puddles again? No, we don’t know of any such mechanism, do we?
Back to CO2: The southern hemisphere has another mild barrier to C13 equalization with the northern hemisphere. C13 is absorbed a little more by tropic-loving C4 carbon fixation plants than by the plants using the C3 version. C3 and C4 both favor C12, but C4 a little less so.
And on the CO2 science front: “Scientist Models The Mysterious Travels Of Greenhouse Gas”
* Carbon “measurements don’t agree with current computer models of how plants and soils behave” (OK, problems with both carbon science and models.)
* “We want to know how the sources and sinks of carbon will evolve in the future, and the only way we can manage climate change is with scientific information.” (With information? It’s about time.)
* “a powerful new tool Michalak will be using—NASA’s Orbiting Carbon Observatory (OCO)” (Oh, dear. Well, that’s not going to work for a while.)
I do not call 2 ppm a year dramatic change.
I am sure that flooding of planes, either deliberate as in new rice fields, or nature induced change of a longer rain season, much more than by 2ppm the atmosphere, per day even. If there were a runaway mechanism from GHG t should run away right then and there. i.e., more heat, more water, more heat , more water,…
Who needs CO2?
I’ve pointed this out before, but another linkage between CO2 and temperature is the rate of increase in CO2. Behold:
http://www.woodfortrees.org/plot/esrl-co2/mean:12/derivative/plot/hadcrut3vgl/from:1958/scale:0.4/offset:-0.2
There must be less animals “Farting” methane in the Southern Hemisphere!
George E. Smith (16:52:53) :
George, you’re not getting the essential point about atmospheric residence times. The residence time of individual water molecules in the atmosphere is small and therefore the atmospheric water vapour concentration comes rather quickly to equilibrium defined by the local atmospheric temperature and pressure. In other words the fact that water molecules have a short residence time in the atmosphere means that the atmospheric water vapour content is locally “set” by the atmospheric temperature and pressure.
We can understand this from simple knowledge of the temperature and pressure dependence of the saturation point of air, and can measure the phenomenon in the atmosphere directly, observing the reduction in water vapour concentration as the atmosphere cools on short/medium timescales (due to volcanic eruptions/ La Nina events or even the sun setting), and its enhancement as the atmosphere warms (it turns out that so far the atmosphere tends to retain a relatively constant relative humidity on average as the atmosphere warms/cools. Again we can measure this in the real world.
The short residence time relates significantly to the response time of water vapour to changes in temperature/pressure.The latter occurs quite quickly so the water vapour concentration is near equilibrium with the temperature. That’s a fundamental difference between the water vapour and CO2. CO2 atmospheric concentrations can be varied indeendent of temperature/pressure. While atmospheric water vapour concentrations drop after volcanic eruptions (response to cooling atmosphere) CO2 levels don’t drop. While CO2 concentrations rise cumulatively as we pump the gas into the atmosphere, water vapour levels only rise in response to changes in atmospheric warming/cooling. So enhanced CO2 concentrations provides a direct additional forcing which causes atmospheric warming. Water vapour levels rise in response to the warming as a feedback, providing an amplification of the primary warming.
Climatologists don’t “ignore water vapor greenhouse effect”…they just address the phenomenon correctly in line with our understanding and real world evidence. It’s science George…not undergraduate style politics about “Leftist behavioral control”!
Anybody have a ref. for the little-known-because-punctures-paradigms paper showing there is a measurable increase of CO2 from the regular influx of mini-comets? With natural carbon sequestration that we cannot avoid, like peat>coal and shells>chalk, I think we need all the CO2 we can get. For the sake of the science, I’d like the source. When I saw it it seemed well-done.
I notice the overall d13C whatsit goes down from about -7.8 to about -8.4 over 10 years. Far bigger annual fluctuations are likely due BOTH to summer vegetation depleting the 12C levels and raising the 13C proportion, AND to winter fossil fuels higher use lowering the 13C proportion – so we cannot measure either factor absolutely. But the overall 13C lowering – what does that portend?
I think the geologist Prof Segalstad has some answers in this summary of his 2008 paper
Carbon isotope mass balance modelling of atmospheric vs. oceanic CO2
Stable 13C/12C isotope ratios, expressed as δ13C in permil vs. PDB, give us the only way to unequivocally determine the fraction of anthropogenic CO2 in the atmosphere. The natural atmospheric CO2 reservoir has δ13C -7 when in isotopic equilibrium with marine HCO3- and CaCO3. CO2 from burning of fossil-fuel and biogenic materials has δ13C -26. A pre-industrial CO2 value of 280 ppmv in air was assumed by IPCC based on selected low value CO2 data from ice cores (omitting measured high values up to 7,400 ppmv), matched with contemporary measurements by transposition of data with different ages (Jaworowski et al. 1992). IPCC claims that the rise in CO2 to 353 ppmv in 1990 and 379 ppm in 2005 is only due to anthropogenic CO2 (IPCC 1990, 2007).
δ13C reported for atmospheric CO2 was -7.489 in Dec. 1978, decreasing to -7.807 in Dec. 1988 (Keeling et al. 1989). If the decreasing δ13C was only caused by mixing natural CO2 with CO2 from burning of fossil fuels or plants (79%/21% CO2 mix; lifetime 50-200 years; IPCC 1989), the current atmospheric CO2 δ13C should be -11, much lower than reported. The December 1988 atmospheric CO2 composition was computed for its 748 GT C (GT = 1015 g) total mass and δ13C = -7.807 for 3 components: (1) natural fraction remaining from the pre-industrial atmosphere; (2) cumulative fraction remaining from all annual fossil-fuel CO2 emissions; (3) carbon isotope mass-balanced natural fraction. The masses of component (1) and (2) were computed for different atmospheric lifetimes of CO2.
The result fits a lifetime of 5 years, in agreement with 14C studies. The mass of all past fossil-fuel and biogenic emissions remaining in the current atmosphere was 30 GT C or less, i.e. maximum 4%, corresponding to an atmospheric concentration of 14 ppmv. The implication of the 5 year lifetime is that 135 GT C (18%) of the atmospheric CO2 is dynamically exchanged each year.
Partitioning of CO2 between atmosphere and hydrosphere is governed by Henry’s Law, implying that 50-60 times more CO2 is dissolved in the oceans than in the atmosphere. Due to the retrograde solubility of CO2 in water, less CO2 will be dissolved in water at higher temperatures.
At least 96% of the current atmospheric CO2 comes from non-fossil-fuel sources, i.e. natural marine and juvenile sources. Hence for the atmospheric CO2 budget marine degassing and juvenile degassing from e.g. volcanic sources must be much more important, and burning of fossil-fuel and biogenic materials much less important, than hitherto assumed.
Thermochemical modelling of calcium carbonate in seawater shows that pH would have to be decreased by 2 units, and H+ activity increased by 100, for Ca carbonate to dissolve at 25°C. By increasing atmospheric CO2 this would by itself require 100 times the present CO2 level. However, mineral buffers in the sea constitute an infinite buffer capacity (Stumm & Morgan 1970), making carbonate destructive ocean acidification from anthropogenic CO2 impossible.
Lucy Skywalker (07:00:25)
Your link doesn’t work. Can you check it?
Otherwise there doesn’t seem to be any paper published by a Dr. Segalstad with a 2008 date. In fact the most recent paper published by a likely Segalstad (TV Segalstad – is that him?) seems to have been 1992…
“I think the geologist Prof Segalstad has some answers”
Good, fuel and a fan for the flames.
foinavon:
de Jager, Usoskin 2006. Knock yourself out.
Lucy Skywalker (07:00:25) :
Dear Lucy,
Segalstad is – again – confusing between what is still in the atmosphere as individual molecules from human origin (about 6% nowadays) and the cause of the increase of the total mass of CO2 in the atmosphere, which is almost entirely from human origin. But even if the emissions are twice as high as what is seen as increase in the atmosphere (which excludes nature as source, it is a sink), the year by year seasonal exchange as given by Segalstad replace about 20% of all CO2, including human CO2 with (deep) ocean CO2, but that says nothing about how much excess CO2 is released or absorbed as total (as nicely described by Chris V.).
Thus the seasonal movements reduces the % of human CO2 in the atmosphere in ratio with the exchange rate and the mass of CO2 in the atmosphere (150 GtC / 800 GtC), while the sink rate is currently only 4 GtC on a total of 800 GtC. If we should stop the emissions today, the CO2 levels in the atmosphere would drop with 2 ppmv, the year after with 1.5 ppmv,… Thus with much longer half life times than 5 years to go back to pre-industrial levels.
So, while the reasoning of Segalstad is perfectly valid for how much CO2 of human origin still is in the atmosphere, that doesn’t give any indication how long the excess mass of CO2 will remain in the atmosphere, as that is completely independent of the molecular exchange rate.
Here a graph which shows what happens in the atmosphere and upper oceans if you add 100 GtC CO2 (about 50 ppmv) at once and let nature do the rest:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/fract_level_pulse.jpg
where FA and FL are the fractions of human CO2 in air and upper oceans, FA/FL their ratio, tCA total carbon in the atmosphere and nCA total natural carbon in the atmosphere (human CO2 is the difference), all based on realistic exchange rates.
Hi,
Isn’t co2 freezing (−78.5 degC) , forming tonns of dry ice on the ground down there during the winter? 🙂
-pmd
“”” George, you’re not getting the essential point about atmospheric residence times. The residence time of individual water molecules in the atmosphere is small and therefore the atmospheric water vapour concentration comes rather quickly to equilibrium defined by the local atmospheric temperature and pressure. In other words the fact that water molecules have a short residence time in the atmosphere means that the atmospheric water vapour content is locally “set” by the atmospheric temperature and pressure. “””
Well Foinavon, you seem to not be getting the point that there is no “essential point about atmospheric residence times.”
Residence time is a last gasp desperation to shore up a failed thesis that CO2 can cause runaway manmade global warming. ‘We’ve already put so much manmade CO2 (which is special) in the atmosphere that even if we all stopped all CO2 emissions tomorrow it is too late and the temperature will rise forever. ‘ Have you seen those catastrophe claims trotted out to the American public.
And to justify these 1000 year residence times, they talk about the weathering or rocks. Mother nature’s growth cycle is going to drop the CO2 by 6ppm in four months, and then she’s going to quit for the day, and we’ll have to wait for some rocks to take out the rest.
Hello! earth to humans; we only have to get down to 280 ppm; how about 250 for a nice round number, that worked for countless thousands of years without upsetting Michael Mann. We aren’t shooting for zero, so we can forget about the rocks.
Whatever heating may have happened and possibly be caused by ‘greenhouse gases’ such as water vapor, CO2 and CH4, or O3, etc, has not been affected one whit, by whatever “residence time” any one or all of those species may have to remove the last molecule of it from the atmosphere.
The only thing that is involved in the molecular absorption process of thermal IR radiation, is how many of those molecules are in the atmosphere at the time that the radiation is there and avaiable to be intercepted. It doesn’t matter if the coach runs the ozone molecule off the field as soon as it captures its photon and transfers the energy to the rest of the atmospheric teram; and replaces it with another identical molecule; or whether he leaves the same one out there to grab another photon. the only thing that counts is how many are there at any time.
So residence time is a total red herring and has nothing to do with atmospheric warming.
Both water vapor, and carbon dioxide are permanent components of earth’s atmosphere (in human time scales), and water vapor is there in quantities that make the CO2 amount negligible in comparison, and the water vapor is far more efficient in warming the atmosphere than CO2 will ever be or has ever been.
It isn’t CO2 that warms planet earth up from its orbital equilibrium black body temperature; it is water vapor.
And how long it takes for all of a ghg to vanish once humans stop emitting it is totally irrelevent to the problem. Residence time is just a smokescreen to make CO2 seem important; which it isn’t; except for plant (food) growth.
Some 20% of present world food supplies can only be explained with the inclusion of that extra 100 ppm of CO2, which is all emitted by human beings driving SUVs.
So which 1.2 billion of the world’s population would you choose to eliminate so that we can get back down to 280 ppm of CO2 in the atmosphere ?
I can’t believe all the totally wasted effort to prove that some CO2 molecule found somewhere up in the earth’s atmosphere, was actually exhaled by a particular person here on earth, and needs to be replaced by one that was emitted by something wonderful and natural, like a lightning strike ignited forest fire in Australia.
And how about this little jewel of wisdom; “”While atmospheric water vapour concentrations drop after volcanic eruptions (response to cooling atmosphere) “”
Now who’d a thunk it; a mountain blows its top, driving an enormous amount of thermal energy from the earth’s interior into the atmosphere, and the atmosphere responds to all that extra energy by cooling down. Now there’s a trick for you. So the colder atmosphere responds by raining so it removes some pesky water vapor from the atmosphere.
So perhaps we should fire that high school teacher who tried to teach us that the dust and ash particles from that eruption acted as substrates for water vapor molecules to condense on, to form water droplets and ice crystals; which then formed up into clouds; which raised the local albedo of earth, reflecting sunlight back into space; and then those clouds blocked even more sunlight from reaching the ground so it got dark and cold underneath, so the ground cooled down due to lack of solar energy reaching there. Wow! what an idiot she turned out to be with that yarn.
Now it’s all clear; the hot Volcano cools the air; the relative humidity goes up till it’s over 100%, and then it rains. Hey I finally learned something !
George
“”” Chris V. (20:16:55) :
George E. Smith (16:52:53) :
Why do you find dew on the grass on summer mornings?
I think that demonstrates that water vapor concentrations are a feedback to atmospheric temperatures (even though water vapor is a GHG). “””
Maybe because at my place, we don’t have the sun warming the ground during the night time, so it cools down to where water droplets can nucleate on the grass leaves. But a foot above the ground we don’t have any grass leaves for water to condense on (not on my lawn), so it doesn’t condense there. Same thing happens in my shower in the morning, except the dew is on the mirror instead (no grass in my bathroom to form on).
Thanks for the physics lesson on the dynamics of evaporation.
So the residence time of a CO2 molecule is a millisecond when it is in a coke bottle; but when it gets up in the ionosphere it may have a residence time of a million years.
So is the man made global warming due to fossil fuel CO2 in a can of coke more dangerous than the global warming due to a million year lived CO2 specimen in the ionosphere; that maybe was emitted originally by a polar bear panting in an ice free arctic ocean.
And no; your little Lawn dew question doesn’t have anything to do with “feedback” ; it is merely a demonstration of a physical property of H2O, and you can find tables of that property in any CRC Handbook of Chemistry and Physics. It’s on pages D-110, 111 in my 1967-68 48th edition.
George
“Gary, are you being seduced by the capital letters?”
No, I’m seduced by clarity, acheivement, perspicuity, elegance of manner, intellectual discipline, fearless integrity and yes, seeing my feeble thoughts seconded by my betters.
George E. Smith (09:47:26)
O.K. George, fair enough. You want to talk politics again. But this really is a straightforward science issue, and you can be sure that scientists and the scientific advisors that inform policymakers, understand the simple evidence that water vapour concentrations come rather quickly to equilibrium with the local atmospheric temperature and pressure, and that responsive changes in water vapour concentrations act as an amplifier to any primary factors that affect atmospheric temperature. That’s what the evidence indicates. The politics is another matter altogether!
George, it’s fun to use sarcasm on blogs, I do agree (we Brits quite like sarcasm!). But if we’re considering science we really should address that properly:
e.g.:
Brian J. Soden et al. (2002) Global Cooling After the Eruption of Mount Pinatubo: A Test of Climate Feedback by Water Vapor Science 296, 727 – 730
“The eruption of Mount Pinatubo in the Philippines in June of 1991 resulted in unprecedented observations of both radiative forcing from volcanic aerosols as well as the climate system’s response to this forcing. Satellite observations confirm the decrease in solar heating due to Mount Pinatubo aerosols (20-22), which led to a global cooling of the lower troposphere (23, 24). Associated with this cooling was a reduction in the global water vapor concentrations, which closely tracked the decrease in temperature (25). ”
So yes, volcanic eruptions do cause the atmosphere to cool (and the surface temperature), and the atmosphere dries a tad in response. This is pretty basic stuff. Incidentally, I wouldn’t be too hard on your high school teacher. She gave a pretty decent explanation (even if not quite right) and the main thing for a schoolteacher is to stimulate the interest of the urchins in her charge, which she evidently did in your case!
Michael D Smith (18:30:58) :
http://rigo.altervista.org/papers/engineering_procedure.pdf
Great Mike. Ridicule my statistics understanding, then send me to a foreign language engineering website ;~D
“volcanic eruptions do cause the atmosphere to cool”
We note that ultraplinian eruptions such as Pinatubo require 20% of ejecta in the form of H2O and CO2 to support the column. This means the VEI 6 eruption ejected roughly the same order of magnitude in CO2 as the yearly anthropogenic contribution. Yet nary a bump in the MLO trend. Curious.
“”” foinavon (10:52:19) :
George E. Smith (09:47:26)
Residence time is a last gasp desperation to shore up a failed thesis that CO2 can cause runaway manmade global warming.
O.K. George, fair enough. You want to talk politics again. But this really is a straightforward science issue, “”
Near as I can tell, you are the only one mentioning politics. Of course it’s a straight science issue; and the issue is that so-called GHG effects depend on the amount of GHG molecules, most of which are water, are in the atmosphere; and it is unrelated in any way to how long any single identified molecule of any species spends in the atmosphere before being replaced by an identical molecule of the same species which will do the exact same thing as the first one.
As for Mr Soden et al: “”” “The eruption of Mount Pinatubo in the Philippines in June of 1991 resulted in unprecedented observations of both radiative forcing from volcanic aerosols as well as the climate system’s response to this forcing. Satellite observations confirm the decrease in solar heating due to Mount Pinatubo aerosols (20-22), which led to a global cooling of the lower troposphere (23, 24). Associated with this cooling was a reduction in the global water vapor concentrations, which closely tracked the decrease in temperature (25). ” “””
So why were these observations unprecedented; nobody ever noticed that volcanic eruptions resulted in cooling before; seems there was this Krakatoa thing long before there was any satellite observations. Come to think of it, I grew up in a city built on about 60 volcanoes; luckily none of them erupted and spewed out a bunch of aerosols.
It wasn’t the volcanic eruption that caused the atmosphere to cool and the surface temperature; it was the clouds that formed on the ash and dust; yes I know you climate scientists like to call them aerosols; but call them what they are; ash and dust. I was under my bed reading the principles of operation of the Wilson Cloud chamber, in an encyclopedia, while other kids my age (back then) were out playing hopscotch; so I think I understand at least basically how water droplets form, and why they don’t like to form without s surface to form on; even it is just a microbe, or a charged particle track caused by a cosmic ray primary striking the atmosphere.
But we don’t want to go anywhere near any suggestion that clouds might result in cooling of the atmosphere and surface; that might lead people to believe that water in vapor/liquid/solid phases was in complete control of the temperature as a result of positive feedback warming by the vapor balanced against negative feedback cooling by the solid/liquid cloud phases; something that Water alone can accomplish in the atmosphere; needing no assistance or trigger from CO2 or anything else.
And as for the atmosphere being in any way in equilibrium; I’d sure like to see some peer reviewed scientific paper where somebody actually observed such a phenomenon.
Of course it’s basic stuff, I learned it all back in the equivalent of 8th grade.
So why try to confuse the issue by raising the spectre of human emitted CO2 remaining in the atmosphere for 200-1000 years; when that, whether true or false, has nothing to do with the process of warming the atmosphere or surface.
But I’m not interested in trying to change your mind; but I am interested is seeing that my kids and grandkids aren’t taught a lot of nonsense about CO2 being a dangerous air pollutant that needs to be taxed.
“”” Joel Shore (17:29:08) :
George E. Smith says:
Oh forgive me; now I get it; the reason why climatologists ignore water vapor greenhouse effect, is that they can’t hang the problem on us humans; we don’t control it, so they can’t use it to hammer us into meekly accepting their Leftist behavioral control of our lives;
They don’t ignore water vapor. They just don’t see a mechanism by which water vapor concentration in the atmosphere will spontaneously change and produce dramatic climate change on its own. Do you know of such a mechanism?
The fact is that humans are dramatically changing the levels on CO2 on a timescale that is very rapid geologically speaking. It is not a “Leftist” plot to be concerned about the consequences of this. It is simply a combination of science and common sense. “””
Joel,
I bring this back up again to affirm that I do not consider ALL (sorry about the caps) climate scientists to be Leftists. But some are; notably Pachauri of the UN’s IPCC; well he’s a railway engineer, and since old trains put out a lot of soot and smoke and water into the atmosphere, which evidently upset him, that qualifies him as a climate scientist; some say the world’s leading climate scientist; which is why he was invited to speak to Barbara
Boxer’s Senate committee on environment and public works just yesterday I believe; at least in the last few days.
But the program of the likes of Pachauri and his band of scientists; fully 20% of whom actually have some real involvement in climate science; is to use the threat of runaway manmade global warming for which no evidence yet exists; to stop the industrial base of the developed world in its tracks; and control their behavior in the name of environmentalism.
Now that part IS (there’s those caps again) a Leftist; some would say Marxist position.
But the Leftist comment was not pointed at anyone on this forum; just those prominent in the public awareness, who trumpet the urgency of drastic action immediately; even if ten years after James Hansen’s dramatic plea to the Congress; accompanied by universal concensus predictions of disaster; absolutel none of what was predicted (up to now) has actually come to pass; and not a hint, that any of it is going to start happenning soon; despite his ratcheting up the rhetoric on the tenth anniversary of his chicken little speech.
So I apologise to any climate scinetist present who feels I may have accused him of being a leftist; and I apologise to all who don’t understand the use of capitals to imply emphasis, rather than the use of an underline, or Italics, or larger font, or any of the fancy tricks of web awareness. I have a shift key; it works for me for emphasis; and although I may be emphasising, I am nto shouting at anybody.
George
pmd (09:08:00) :
Hi,
Isn’t co2 freezing (−78.5 degC) , forming tonns of dry ice on the ground down there during the winter? 🙂
The vapor pressure of the tiny amounts of CO2 in the atmosphere (0.04%) is too low to be frozen out, at – 80 deg. C, but at -90 deg. C it may be in equilibrium with dry ice. But that are even for Antarctica rather extreme temperatures…
George E. Smith (09:47:26) :
Mother nature’s growth cycle is going to drop the CO2 by 6ppm in four months, and then she’s going to quit for the day, and we’ll have to wait for some rocks to take out the rest.
Hello! earth to humans; we only have to get down to 280 ppm; how about 250 for a nice round number, that worked for countless thousands of years without upsetting Michael Mann. We aren’t shooting for zero, so we can forget about the rocks.
The drop of 6 ppmv in four months where you allude on is what happens during the seasons, as plant growth and decay are very much temperature dependent. The overall ratio is about 5 ppmv/°C globally. Opposite to that are the oceans, which have a short term influence on CO2 levels of about 3 ppmv/°C, up to 8 ppmv/°C over decades to millennia.
But as we have a 100 ppmv increase of CO2 in the past 150 years, you need a new (real) ice age to get rid of all that CO2, if you think that temperature will do the job.
Without a real temperature drop, the amount of CO2 in the atmosphere will drop only slowly, at about 40 years half life time. That is slower than the residence half life of about 5 years for individual molecules, but faster than the Bern model of the IPCC predicts. The latter assumes that about 10% of the extra CO2 will remain in the atmosphere near forever. But that is based on using all available oil and much of the coal reserves…
Now who’d a thunk it; a mountain blows its top, driving an enormous amount of thermal energy from the earth’s interior into the atmosphere, and the atmosphere responds to all that extra energy by cooling down. Now there’s a trick for you. So the colder atmosphere responds by raining so it removes some pesky water vapor from the atmosphere.
I think you overestimate the thermal energy of the Pinatubo eruption, that is peanuts compared to the thermal energy from the sun we receive within a day. The cooling which followed the Pinatubo was in first instance the local/regional cloud, where most of it dropped out or rained out within days.
The interesting part is what happened in the stratosphere: a lot of dust and SO2 was injected in the stratosphere. The heavier dust dropped out within a few months, but SO2 indeed formed droplets which grow with water vapor to form bigger droplets. As these droplets reflect incoming sunlight back to space, the insolation on the ground is reduced and the earth cools. As there is little water in the stratosphere, the whole process of growth and dropping out of the heavier droplets (without real cloud formation, too little water) out of the stratosphere did take 2-3 years for the Pinatubo eruption. The cooling at the surface was measured and the drop in water vapor was measured too.
That confirmed that the water vapor in the atmosphere goes up and down with temperature at about constant relative humidity. That also revealed something else: that human SO2 releases have very little (cooling) influence on temperature, as the residence time in average is only 4 days before raining out (against 2-3 years for stratospheric SO2). Thus the large cooling influence of human SO2 emissions as incorporated in current climate models (and consequently the large warming influence of CO2) is overblown…
Thus while a disagree with you about the lifetime of excess CO2 in the atmosphere and the cause of the Pinatubo cooling / influence on water vapor, I agree that the influence of CO2 on climate is much lower than climate models “project”…
George E. Smith (10:13:39) :
http://en.wikipedia.org/wiki/Dew_point
When air cools, it can’t hold as much water vapor, so some condenses out as dew.
Whether you want to admit it or not, that shows that the concentration of water vapor in the atmosphere is a feedback of the temperature.
It is my recollection that the association with volcanic eruptions and cooling began a bit earlier. In the 1970’s volcanic aerosols were being mentioned in regard to global cooling in publications of the time (see H.H. Lamb Volcanic Dust in the Atmosphere 1970). They were drawing tentative associations between “The year without a summer”, and volcanic activity, but at the time they were simply talking about the shading and reflection effects of particulate dusts and their residence time in the atmosphere. The Eruption of Mt. Agung in Bali in 1963 and the eruption of Volcan de Fuego in Guatamala in 1974 were being specifically mentioned in books of the period in association with volcanic aerosol cooling.
see Genesis Strategy (1976) pg 181
Climates of Hunger (1977) pg 145-148
But the clincher event was the eruption of El Chicon which had 3 eruptions in 1982. That is the eruption that as I recall, they first mentioned sulfur content in the aerosols and its impact on cooling as the droplets circulated in the stratosphere. In fact I understand that El Chicon actually had a greater sulfur related cooling impact than Mt. Pinitubo although the actual size of the eruption was (ejecta) was smaller.
http://en.wikipedia.org/wiki/El_Chich%C3%B3n_Volcano
See the illustration of Mauna Loa Observatory dust observations.
I recall the news items on the “revolutionary” discovery — or perhaps confirmation, that the eruptions sulfur content was the key variable to determine the cooling effect of a major volcanic eruption. It was clearly a period of “developing science” regarding the effect of particulates and global temperatures.
Larry
Joel Shore:
I have reviewed Tamino’s post “Bag of Hammers” for relevance to my discussion.
He does not address the F-Test. He does not explain its purpose-to establish the significance of differences between populations in their differences of response in a selected f(x); that one studies this and the ANOVA battery in courses of Intermediate Statistics; he does not demonstrate the test or attempt to duplicate it with the data but devotes his discussion to a matter of presentation, etc.
He summarizes his discussion with a bald-faced lie repeated here by a number of commenters:
“Ignore, if you can stretch the truth that far, that there’s no evidence whatever that the oceans are a net producer of atmospheric CO2 but there’s very strong evidence they’re actually absorbing. ”
Your representation of this account as pertinent, even the notion that Basic Calculus might somehow be relevant to either Tamino’s discussion or ANOVA, is at best ignorant.
Tamino has once again demonstrated that he/she is a fabulist.
gary gulrud (07:39:18) :
He does not address the F-Test.
gary, you didn’t grasp what Dr. Spencer did: he compared the trend data with the detrended data for the ratio of 13C/12C and compared these two. Of course these have exactly the same shape, as detrending in this case only changes the values on the axis, not the slope of the ratio. Thus with or without F-test, both trendlines are mathematically exactly the same in slope and thus show exactly the same ratio change over time.
I was not aware of that either, but Tamino in this case is completely right: Dr. Spencer compares two slopes which are mathematically identical.
Anyway, even if Dr. Spencer had compared one year (like the 1998 warm El Niño year), where near all of human CO2 (as mass) was retained in the atmosphere, the drop in 13C/12C ratio would have been similar (but not identical) to the long term trend. Simply because the human emissions are so strongly depleted of d13C, that these overwhelm the (near) d13C neutral exchange from the oceans and the strong positive d13C signal from vegetation uptake (about 1.4 GtC vs. 8 GtC from human emissions).
This fancy movie (pretty cool) confirms the NOAA 3-D plot of CO2 from pole to pole showing that at the north pole, the amplitude of the annual CO2 cycle is 17 ppm P-P, versus 6 ppm at Mauna Loa, and essentially zero at the south pole and for most of the southern ocean.
The NOAA plot actually shows a south polar effect of maybe 1 ppm max, and it appears to be double humped, so it seems to be a composite of a northern hemisphere leak through and an out of p[hase southern hemisphere cycle.
I’m not surprised; I think the temperatures at the south pole and southern ocean are such that there is much lesss annual change on CO2 takeup.
I can’t for the life of me figure whay the maximum cycle is at the north pole, instead of lower down in the tree belt; but it certainly doesn’t give me any confidence in any mixing theories, or any notion that Vostok cores are representative of any global phenomenon.
Incidently there really is more land north of +60 north (the Arctic) than there is south of _60 south (the Antactic).
George E. Smith (15:55:19) :
I can’t for the life of me figure whay the maximum cycle is at the north pole, instead of lower down in the tree belt; but it certainly doesn’t give me any confidence in any mixing theories, or any notion that Vostok cores are representative of any global phenomenon.
The deeper CO2 dip at the Arctic stations probably is not only from vegetation (there is a lot of tundra there), but mostly from CO2 absorption from the still cold but ice free Arctic Ocean. Despite that, the yearly averages at Barrow and Mauna Loa are near the same with a few months delay and with a year delay to the south pole, all have quite identical trend slopes. Thus the mixing ratio is fast enough to see the same CO2 level all over the globe within a year at all places away from local sources/sinks (which is mainly in the first hunderds of meters over land). See:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/co2_trends.jpg
As Vostok shows an average of 600 years CO2 level, the seasonal variability plays no role at all. Even the fastest accumulation ice cores (Law Dome, 1.5 m ice equivalent per year) gives the average of 8 years CO2 levels. But these show the same CO2 levels as directly measured at the south pole for the same age, with an overlap of 20 years (1960-1980). See:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/law_dome_sp_co2.jpg
I would think that is mostly driven by the polar region is totally surrounded by tundra consisting of fast growing grasses (Cottongrass in Alaska), and other fast growing species like willow, that compress their entire growing season into 6-8 weeks of 24 hour sunlight and abundant water on the thawed permafrost.
In this respect, I think the contrast between zero growth during the winter and rapid explosive pulse of growth in 6-8 weeks of summer over vast areas of land explain the swings in CO2 content.
By comparison the growth rate of mature Pine trees is relatively slow and spread out in time.
Larry
“gary, you didn’t grasp what Dr. Spencer did: he compared the trend data with the detrended data for the ratio of 13C/12C and compared these two.”
Ferdinand, I told you to study the F-Test and that the presentation was not material to the argument. Are you really so dense, or just congenitally disingenuous?
Dear Ferdinand,
oops, you do it again:
You write:
“With other words, neither the (deep) oceans (too high d13C level), nor the biosphere (a net sink of CO2) are responsible for the recent increase of CO2 or the recent decrease of d13C in the atmosphere (and oceans). Only humans are to blame for the CO2 increase of the past 150 years, not the same as saying that humans are to blame for the recent warming…”
That is still not proven at all! (See my unanswered comment in the older thread.
The d13C only shows, that we indeed burn fossil fuel (and a decreasing pH-value in the upper sea reflects a higher CO2-concentration in the atmosphere). If you look at scenarios were the oceans swallow the CO2-rise (For example because humans pump CO2 from the upper sea into the deep sea), the C13-depleation would continue at very much the same rate if we continue to burn fossil fuel.
This example shows that dC13-level cannot prove an anthropogenic cause! (Neither can the pH-value)
You are wrong!
> Without a real temperature drop, the amount of CO2 in the atmosphere will
> drop only slowly, at about 40 years half life time.
That of course is only true for the amount bigger than the equilibrium concentration!?
All the best,
LoN
gary gulrud (12:53:58) :
Ferdinand, I told you to study the F-Test and that the presentation was not material to the argument. Are you really so dense, or just congenitally disingenuous?
Gary, I am open to any argument, but in this case there is no argument: any test that compares two identical slopes and variability will show you that the slopes and variability are identical! And the slope and variability between two variables is identical, when you substract constant values of the two variables…
Law of Nature (23:46:08) :
That is still not proven at all! (See my unanswered comment in the older thread.
The d13C only shows, that we indeed burn fossil fuel (and a decreasing pH-value in the upper sea reflects a higher CO2-concentration in the atmosphere). If you look at scenarios were the oceans swallow the CO2-rise (For example because humans pump CO2 from the upper sea into the deep sea), the C13-depleation would continue at very much the same rate if we continue to burn fossil fuel.
This example shows that dC13-level cannot prove an anthropogenic cause! (Neither can the pH-value)
You are wrong!
I do agree that the ocean’s pH can be the source or the effect of increased CO2 levels, that in itself is not a proof for humans as source of the increase, it just adds to the overall arguments.
The d13C argument in combination with the mass balance is different. There are two possibilities: either the (deep) oceans are the main source of the extra CO2, or humans. The biosphere can’t be, as that is a proven sink, as can be seen from the oxygen balance (around 1.4 GtC or 0.7 ppmv per year).
The d13C decrease in the atmosphere (and upper oceans) is about 1/3rd of what can be calculated from fossil fuel burning. Thus about 2/3rd is diluted by either extra amounts emitted by the oceans, or by simple exchange between oceans and atmosphere (or a mix of both).
1. The d13C decrease is 1/3rd human, diluted by 2/3rd ocean release:
Problem is then that the mass balance doesn’t fit: the increase in the atmosphere then should be 4 ppmv (emissions) + 8 ppmv (ocean release) – 0.7 ppmv (bioshere uptake), or about 11 ppmv/year. But we see only 2 ppmv/year increase in the atmosphere.
2. The d13C decrease is 100% human, diluted by the about 20% exchange of CO2 over the seasons.
This can fit the mass balance, if about 2 ppmv CO2 more is absorbed by the biosphere and oceans than is released. Including the oxygen balance, that is about 0.7 ppmv by the biosphere and 1.3 ppmv by the oceans.
3. There is a mix of both mechanisms.
Hardly possible, as long as the increase in the atmosphere is less than the emissions.
4. What if we pump all extra CO2 into the deep oceans?
If you do that at all human sources, there is no increase of total CO2 and no decrease of d13C. If you do that after mixing in the emissions, there would not be an increase of total CO2, but still a decrease of d13C. But I don’t see the relevancy for the current situation where the natural sink capacity is only about halve the emissions, thus the emissions still are (near) 100% responsible for the increase in total CO2 of the atmosphere…
Dear Ferdinand,
thank you for your patience with me!
well, my argument is still quite easy and it seems that we are slowly approaching a common ground. I should apologize, my language seems not to be clear enough (thnaks you for untangeling it :))
You wrote:
4. What if we pump all extra CO2 into the deep oceans?
[..] If you do that after mixing in the emissions, there would not be an increase of total CO2, but still a decrease of d13C. But I don’t see the relevancy for the current situation where the natural sink capacity is only about halve the emissions, thus the emissions still are (near) 100% responsible for the increase in total CO2 of the atmosphere…
This simply shows, that the dC13 (like the pH-change) is not a measure of the total rise and hence you cannot blame the anthropogenic CO2 with that arguments (like you did before).
It is possible, that the total amount of CO2 in the atmosphere is either rising or falling while the C13-amount decreases depending of how the deep oceans behave. Thus you seem to need a mass balance which includes the deep oceans and it’s error bars.
Regardless of this argument, I looked at your exponential graph with the change of CO2-concentration after a increase of 100GTC CO2 . .
It seems to me, that from that graph alone a doubling of CO2 is quite unreachable, since an increase of seceral hundred GTC CO2 would provoke an anual dumping rate into the deep sea, which is much higher than any estimated human output . . do i read your graph correctly?
All the best,
LoN
Law of Nature (22:15:46) :
This simply shows, that the dC13 (like the pH-change) is not a measure of the total rise and hence you cannot blame the anthropogenic CO2 with that arguments (like you did before).
It is possible, that the total amount of CO2 in the atmosphere is either rising or falling while the C13-amount decreases depending of how the deep oceans behave. Thus you seem to need a mass balance which includes the deep oceans and it’s error bars.
You should be right if we were pumping CO2 directly in the deep oceans (thus changing the mass balance), but in the current situation, the mass balance is that there is an imbalance of about 2 ppmv/year absorbed by nature, of which about 0.7 ppmv by vegetation (based on the oxygen balance) and 1.3 ppmv by the (deep) oceans. Thus the mass balance simply says that nothing (as net result over a year) is added by the biosphere or the (deep) oceans, so the mass balance doesn’t need to include the (deep) oceans, as these can be assumed to be sinks only. Anyway, indeed it is the combination of mass balance and d13C changes which gives the right answer, not the d13C level alone…
What may be of interest is to calculate the amount of deep ocean CO2 which exchanges directly (or indirectly) with the atmosphere. As the biosphere and the upper level oceans act more as an extra reservoir for d13C changes than as sink (some of the change in d13C returns next season from vegetation decay/warming oceans), it is mainly the deep oceans which are such large that the d13C level going in (at the sink places of the THC near the poles) are practically disconnected from the upwelling deep ocean d13C levels near the equator (a delay of about 800 years). The d13C level of the deep oceans is around zero per mil d13C, while the average fossil fuel d13C level is about -24 per mil and the atmosphere is at – 8 per mil. With different seasonal exchange rates, one can show a reasonable match to the observed data:
http://www.ferdinand-engelbeen.be/klimaat/klim_img/deep_ocean_air_zero.jpg
With about 40 GtC/year continuous exchange from the deep oceans, the d13C reduction calculated from human emissions match with what is observed…
A one-time dump of a lot of CO2 (100 GtC or 50 ppmv in the example) gives a huge initial increase in absorption rate, in ratio with the CO2 in excess to the “baseline” equilibrium, but that is without any further addition. The rate of absorption is also true for (currently) increasing human emissions: the average rate of increase in the atmosphere is about 55% of the emissions, as long as the emissions increase, thus without a limit on atmospheric CO2 levels in that case.
If the emissions should stop increasing and stay at an equal level over the years, the increase speed in the atmosphere would reduce and ultimately stay at a level where emissions and uptake are equal.
Dear Ferdinand,
it’s me again, howdy? 🙂
> Anyway, indeed it is the combination of mass balance and d13C changes
> which gives the right answer, not the d13C level alone…
Well, this seems only a small step away from agreeing with me, that the dC13 only tells you that we burn fuel…
– you just aggreed if the deep sea would uptake CO2 the dC13 in the atmosphere decreases.
– new: if the CO2 in the amtosphere increases independent of the reason, the dC13 in the atmosphere decreases as well (just assume we would pump CO2 form the deep ocean to the near surface)
> With about 40 GtC/year . .
Your number seems about 250% wrong, shouldn’ that be closer to 100GtC/a?
> If the emissions should stop increasing and stay at an equal level over the
> years, the increase speed in the atmosphere would reduce and ultimately
> stay at a level where emissions and uptake are equal.
Of course, I can agree to that, but I was trying to see, how long the peak stays in an atmosphere after the cause is gone and it looks like there is a quite short time constant for that.
Your key argument still is:
> Thus the mass balance simply says that nothing (as net result over a year)
> is added by the biosphere or the (deep) oceans, so the mass balance
> doesn’t need to include the (deep) oceans, as these can be assumed to be
> sinks only
And my question for that still is:
The deep sea is still very close to the equilibrium after the assumed 35% anthropogenic raise, which makes no sense, at least your explanation does not explain this. How can one bucket after a 35% raise in the level be in near-equilibrium with a bucket, which did not experience such a raise?
Well, I give you that the deep ocean takes up more CO2 from fuel if we burn it as if we would not burn it and your mass balance clearly seems to indicate that. But this is not the question, the question should be, what is the reason for the increase? How can you say, that even without any burned fuel we would have the same atmospheric CO2-level? (dC13 and pH-values cannot tell you that)
__
All the best,
LoN