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They caution that this is a derived product, (due to processing, smoothing etc) and does no longer represent raw data on CO2C13, along with other caveats such as this: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
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
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