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Comments 125601 to 125650:

  1. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Yocta - As you may know satellites do not measure CO2. They try to measure CO2 but must be calibrated from - you guessed it - ground stations. And there is no "global" data back from those satellites yet. So how can you use that argument against my position? You make it seem as though all these climate scientists have accurate satellite data on CO2 for years. But the satellites were launched just a year or so ago and are barely working even today. And the American satellite crashed after launch. So what are they climate scientists using for CO2 data?
  2. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    "Where does the CO2 go you ask? - it blows away in the wind - which, sadly, I have yet to see a climate model account for (wind that is)." I'll bite, Ralph. How many model sources have you read (I know you haven't read the Hadley Centre's, theirs is proprietary ...) My guess is you haven't seen a climate model account for anything because you've not studied a single climate model.
  3. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm: "I am using numbers taken from a variety of sources". Care to share those "sources" with us so we can see how reliable they are? You cannot have the variation of a well mixed gas (100% miscible, yes gases are all 100% miscible) with those kind of variations. Of course, if your sources are taking samples from the top of a chimney then they will show higher results than the global average. However, that would not be considered science.
  4. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    RE# ralphiegm You stated earlier (post 31) that you didn't trust that satellites actually measured CO2. Well they do. GOSAT is a Japanese one launched recently that has amongst other things a Fourier Transform Spectrograph. And if you don't trust the validity/accuracy of spectroscopy, then you can throw out most of atomic physics, astrophysics for the last 50 years or so. Look at the references here for more info on the satellite's specs: http://en.wikipedia.org/wiki/Greenhouse_Gases_Observing_Satellite My Japanese isnt too good but in the brochure it lists the satellite with the ability to measure over 56,000 data points. Not quite the zillion that you expect the poor scientists to deliver but if you can't accept that this is good enough then you are wasting everyone's time. GOSAT: Greenhouse Gases Observing Satellite "IBUKI" http://www.jaxa.jp/pr/brochure/pdf/04/sat02.pdf Also, preliminary results have already been released that show CO2 is within the range of 360 to 390 ppm. Initial Analysis of Observation Data from GOSAT http://www.gosat.nies.go.jp/eng/result/download/GOSAT_L2_20090528_en.pdf When scientists talk about considerable variation in the atmosphere it is on the order of 3ppm not the crazy numbers you seem to be claiming. Aircraft observation of carbon dioxide at 8–13 km altitude over the western Pacific from 1993 to 1999 http://www3.interscience.wiley.com/journal/118916481/abstract?CRETRY=1&SRETRY=0
  5. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Ian - I am using numbers taken from a variety of sources. I have no wish to support or diminish this Beck fellow. Jeez - Is the only purpose for this site to squeeze out verbal revenge against skeptics? As to the content of my post which is really the only point I care about - atmospheric CO2 appears to range from 250 to 425 ppm. Is that data wrong too? Where does the CO2 go you ask? - it blows away in the wind - which, sadly, I have yet to see a climate model account for (wind that is).
  6. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Ralpiegem, can you please explain where the CO2 comes from so that its concentration doubles in the very short periods of time shown in Beck's paper. Also, please tell me where it suddenly disappears to after it reaches its high points. The paper you are using is nothing but garbage, and what is worse, if you are an engineer as you have stated, you probably know it is garbage but will use it to support your denier claims.
  7. What ended the Little Ice Age?
    To batsvensson: Reading your comment, I can only assume you have a background in electrical engineering. The problem with this is that you have a high level of math skills, mathematical intuition, systems analysis and computer modeling abilities and wish to actually approach the eco-system as a sincere scientist. I applaud your question. Unfortunately, we are talking about many non linear and dependent relationships that probably are not being accurately modeled. I dont think anyone is to blame, nor in a position to answer your question. It almost seems like there is a limit to what we humans can know, predict, and control. I am sorry for sounding so pessimistic, yet on the lighter side, I think we should also be grateful for the margin of error that Divine Providence at least so far has allowed mankind. My guess is that since 2/3 of the planet is water, there is a self imposed restriction as to how much damage we can actually do to ourselves.
  8. Predicting future sea level rise
    rajpe, to be in topic i will consider just #1 and 2. During the last interglacial sea level was several meters (4-8) above current level and Greenland was about 3 °C warmer and with less ice than today. That makes sense. What does not make sense is to assume that we are naturally heading there again. Indeed, sea level has been almost constant in the last 2000 years and from about 7 to 2 thousands years ago it rose only a little and very slowly. There is no indication at all that we were heading toward the same state as the last interglacial. Maybe you are right and it's too late to save the Maldives whatever we may try to do starting from now. But it could be worse, much worse than just the Maldives.
  9. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Riccardo -I think that CO2 ranges from 250 to 425 ppm globally based on the literature. So it is amazing that (some) climate scientists are in a panic over this issue.
  10. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm, you have local and global mesurements; you also have the physics and simulations that match the experimental data locally and globally (by the way, not all natural systems are too complicated to be described quantitatively). Putting completely arbitrary minimum requirements to belive in the data indicates that you simply (and dogmatically) do not want to. It's ok for me, your choice. But do not pretend to judge thousands of (irresponsible ..) scientists (and many more common people) on this basis.
  11. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    TerryG, do not make the mistake made by ralphiegm, not any kind of pollutant, molecule or particulate behave the same. It is well known that the global circulation tends to separate the two emispheres, but it changes with season and it's not "perfect". If you have a very stable (chemically inactive) and long lived specie it will first mix vertically through the whole troposphere (and beyond) and then mixes globally in the atmosphere. You may also notice that the seasonal cycle is much less pronounced in the southern emisphere; this is because there's much less land (vegetation) and there's no enough time for the northern emisphere CO2 to mix. So it's just a matter of giving the CO2 time to mix and it will.
  12. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Jim - Are you saying that CO2 can only be in concentrations ranging from 360 to 380 ppm?
  13. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    It seems Ralph is getting some of his ideas from Herr Beck's paper in Energy & Environment. http://www.realclimate.org/index.php/archives/2007/05/beck-to-the-future/ That explains much.
  14. Predicting future sea level rise
    Please excuse me, but am I missing something? Does not most of the discussion on sea level rise miss the most important point? As the Koop article in Nature, 17DEC09, points out, the maximum sea level during the previous interglacial was about eight (8) meters above the current sea level. Does this not suggest the following: 1. Future sea levels will likely be 8 meters higher than we have now - with no help from man. (Things are NOT different, this time.) 2. Don't worry about the Maldives, etc. They will be gone, whatever we do. 3. Don't waste current resources (yen, eruos, dollars, etc.) on wishful-thinking projects. 4. With regard to Climate Change, do only science and do no politics, i.e., if you are a politician, butt-out. P.S. Please don't think that fast climate change must be man-made. Don't believe me, read "The Two Mile Time Machine".
  15. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Catprog - see the problem is you are assuming CO2 is well mixed. You have no way of ever proving that assumption unless you take the zillions of measurements necessary to prove such a thing or if you had a dispersion / diffusion model that explained how CO2 can populate the atmosphere on its own. It appears that climate study is based on the super smooth mixing of CO2 in the atmosphere. It appears that CO2 can range from 250 to 425 ppm looking at 5 year smoothed data. And diurnal cycles in CO2 varying by 50 ppm. And seasonal variation from 350 to 415 ppm (all nos. rounded by me from the literature for illustrative purposes). So how can anyone have such faith in the CO2 well-mixed assumption given the crazy variations in CO2. It does not make sense to take a dogmatic position on CO2 being uniformly distributed through the atmosphere.
  16. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Have been following this web site for a while. I have some observations and questions. Of the CO2 we produce the northern hemisphere produces what percentage? 90%,85% or 80% It is then stated, in this thread that the CO2 then evenly mixes through the atmosphere. But on this web site it's a tale of to hemisphere's: http://www.livescience.com/environment/080930-chemical-equator.html The Chemical equator as they decribe it, where the poluted air is in the north and the south is considerably cleaner. Now I have seen CO2 readings from Cape Grim, Tasmania, Australia. http://www.esrl.noaa.gov/gmd/ccgg/carbontracker/co2timeseries.php (Go to: Site CGO_01d0) and as you can see they indicate CO2 levels at 385ppm at present time. The point is I'm finding it hard to believe that northern hemisphere CO2 is the cause of ppm levels to rise in the southern hemisphere.
  17. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    @ralphiegm not to disrespect any scientist - but do you believe there are enough data points throughout the entire shell of the atmosphere to accurately model CO2. Show me one station that shows a big difference then the other and I will be more inclined to believe the CO2 needs to be measured more finely. Why does the Antarctica CO2 graphs show a similar annual increase to all the others if CO2 is not distributed relativity evenly. I think a particulate can be an indicator of mixing in the atmosphere. If you get a bunch of small neutrally buoyant pieces (Particulates),some red food dye(CO2) and water(Atmosphere) and mix them all together by stirring. The red food dye will be distributed evenly while the pieces will all collect together underneath the mixer. ground CO2 data at grid points of 5 miles Why 5 miles and not 1 mile. If you really believe that CO2 is not mixed evenly go out and buy a CO2 meter. on your daily travel look at the readings. if you find a big variation then look around for a big emitter of CO2(and make sure you are measuring the outside not the inside). If you can't find one then look up how to get a science paper published because you have found something no one has found before.
  18. What ended the Little Ice Age?
    "Meehl 2004 is also confirmation that past climate change tells us how sensitive climate is to radiative forcing." I acknowledge this as an possible interpretation of data. However, using words like “sensitive” is misleading when there is still no clear picture about what the bandwidth of the natural variation actually is. What “sensitive” suggest is that there exists a certain (known) signal with a certain (known) bandwidth and that due to “radiative forcing” the center and/or shape of the bandwidth has changed. Is such interpretation supported by the analysis in the report? If not, another interpretation could be that the signal is very noisy and the bandwidth is great which can be put in other words as climate is able to vary fast over time.
  19. What ended the Little Ice Age?
    I went to the "hockey stick page" but the graphs don't show the MWP. They only go back to 1500 except one which is only Northern Hemisphere. I think the MWP is instructive in this debate.
  20. What ended the Little Ice Age?
    Why don't the graphs on this site go back to 1000 AD? It appears the warming shown is something new without a little more historical context.
    Response: More context is always a good thing. For discussion of temperatures going back 1000 years, see the hockey stick page. For temperatures going back 450,000 years, see "CO2 lags temperature". For temperatures going back 540 million years, see "CO2 was higher in the past".
  21. What ended the Little Ice Age?
    This is a good article. Firstly, it's hard to get much about the contributions from the sun out of most people advocating AGW. The period from 1880s to 1940s shows the sun has an important effect. From about the 1940s-1960s, those advocating the continuance of relatively strong warming effects from the sun have to resort to scrambling for 'unknowns' such as cosmic rays, long heat lag effects, and who knows what else (magnetic fields, UV etc etc), but they are still a possibility. One has to remember that the sun is not just a simple and unchanging ball of fire; it is still quite possible that solar effects, as yet not understood, contribute strongly to warming since the mid 20th century, although admittedly, there isnt any known mechanisms to account for this-at least not yet. Without these 'unknown' solar possibilities, including long heat lag effects, the skeptics arguments for warming since the 1950s are relatively weak. PS. Also, I think the papers advocating increased build up of heat in the oceans and various disequilibrium effects etc, are flawed because they generally rely on modelled forcings relating to greenhouse gases; like the hockeystick, these papers, the data and their conclusions are somewhat manipulated and unreliable. I dont trust them very much. A good example is Hansen 2005 (elsewhere on this site), where his 'warming in the pipeline' calculations are based on modelled effects and assumptions from greenhouse gases. Good article above though.
  22. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Riccardo - not to disrespect any scientist - but do you believe there are enough data points throughout the entire shell of the atmosphere to accurately model CO2? In my estimation there is not a computer model in the world that can predict future CO2 and future global temperatures. It is difficult to model a 2 dimensional system such as a river for pollutants with any degree of accuracy. Now, we are being told that the world can be modeled for a sneaky CO2 molecule. Complicating matters infinitely is the fact that CO2 is part of the carbon-based life-cycle on our planet. I can only guess how many assumptions need to be made in such a model - which starts out with bare-boned CO2 data to begin with. I think its an impossible task - and irresponsible of scientists to imply to the public that they know firmly anything at all about the climate other than what the weather channel can give us. BTW - I have extensive computer modeling experience and a graduate degree in environmental engineering and know that models of natural systems are nothing more than curiosities. I don't like to see others touting these models as truth - cause they're not. I would listen to a model of global CO2 that had 100 years of data tied with accurate temperature data and ground CO2 data at grid points of 5 miles including the oceans and air columns. Until that data arrives I'll be skeptical. No "tree rings" for me.
  23. Could CFCs be causing global warming?
    Riccardo, Agreed. Correlation is great for initiating an investigation, but not for demonstrating a cause and effect. The increase in Scotch whiskey consumption in Pennsylvania increased by 3.2% in 2009. The increase in teachers pay in Pennsylvania increased by 3.2% in 2009. Ergo..... Maybe a bad example; that probably is a cause and effect.
  24. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm, "Riccardo - are you saying that Antarctica is releasing CO2 ?" Actually the opposite. CO2 is NOT emitted in Antarctica but it's there at roughly the same concentration as anywhere else because it is well mixed. And it is well mixed because it is long lived and it can not condense into liquid nor evaporate from an existing liquid. The very opposite is true for water vapour which infact is NOT (at all) an indicator of the mixing of the atmosphere. Hence your supposed "proof" (sic) of incomplete mixing is faulty. "A true scientist would be worried about such problems." Please do not suppose that all the scientists are not true scientist just because they do not agree with you. And do not think you can teach people how to do their job while you're nowhere near the field.
  25. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Jim - I think a particulate can be an indicator of mixing in the atmosphere. Why not? My point being only that the data appears to be so limited on the CO2 in the atmosphere since there are only 200 or so data sets. I think I have shown that there is proof of incomplete mixing in the atmosphere by merely viewing the variability of clouds. My observation is as (in)accurate an assessment as "tree rings" are for long term temperature models. Further, the NASA global CO2 map shows no correlation between industrial land uses and the highest CO2 values. A true scientist would be worried about such problems.
  26. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    "are you saying that Antarctica is releasing CO2 ?" Easy enough to actually look up. Hmmmm, Mount Erebus, erupted in 2008 & 2009. Date of cited ARIS CO2 plot, July, 2008. I'm just sayin.
  27. It's freaking cold!
    What do you think about Anthony Watts' attempted debunking of the Meehl 2009 report by complaining that it "cherry picked" temp records from 1950 on when 1930 had more record lows than highs? See http://wattsupwiththat.com/2009/11/16/why-ncars-meehl-paper-on-highlow-temperature-records-is-bunk/ It looks to me like Watts is really looking at numbers of record highs and lows and not ratios of highs to lows, but nonetheless it would be nice to see a debunking of the debunking. Overall, it would be even nicer to see a global report on record highs vs record lows to see if the trend Meehl et. al. found in the U.S. is really a global phenomena.
  28. What ended the Little Ice Age?
    DeNihilist, if a small sun variation can induced detectable increases in temperature it can only mean that climate sensitivity is much larger than expected or that some fast feedback specifically related to the sun forcing must be acting. This would be good news for the "it's cosmic rays" belivers. Unfortunately (for them) we know it can not be it. Problems also arise when considering the big picture of the climate of the past, it would be hard to explain the temperature difference between glacial and interglacial with such a huge sensitivity (plus the slow fedbacks in action).
  29. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Ralph, clouds are not an indicator of mixing, they are an indicator of 1) a temperature low enough that water vapour will condense into water droplets and 2) the presence of sufficient nucleation particles for them to condense onto. "Assume I said pollen, or dust..." Then you would be talking about solids, not gases. CO2 is a gas.
  30. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    RE: ralphiegm Clouds are made up of frozen droplets, that is each frozen droplet contains millions of water atoms bonded together. Water molecules have a strong dipole moment and so so will form crystals quite readily if given the right conditions, and if I quote wikipedia for water... "Oxygen attracts electrons much more strongly than hydrogen, resulting in a net positive charge on the hydrogen atoms, and a net negative charge on the oxygen atom. The presence of a charge on each of these atoms gives each water molecule a net dipole moment. Electrical attraction between water molecules due to this dipole pulls individual molecules closer together, making it more difficult to separate the molecules and therefore raising the boiling point. This attraction is known as hydrogen bonding." CO2 is very different when in the atmosphere not only is in the gas phase (so you won’t get them bonding together like water) but it has a zero dipole moment . Thus you would expect that its behavior to be different from water in the atmosphere given it being in a different phase and having a distinctly different electronic structure. The 'hard sphere model' which I think you’re trying to compare it to (ping pong balls, pollen or even billiard balls) is a good model for other more simpler molecules and systems but it will not adequately represent these molecules in the atmosphere.
  31. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm, your reasoning is correct if two conditions are met: 1) no phase transitions (gas/liquid, liquid/solid etc.) 2) equally long lifetime and source/sink stength of the molecules in the atmosphere. Neither is met by water vapour; it condenses to form liquid droplets or solid crystals (clouds) and viceversa it can readly evaporate from the oceans or land; it's lifetime is quite short. If you accept that CO2 lifetime is long and that no liquid or solid CO2 can exisist in our real atmosphere, even common sense will indicate that it may be considered well mixed. One final remark, i'm sure you know that a lot of volatile substances has been found trapped in the antarctic ice even if they have been originated somewhere else in the planet. The same happens to CO2.
  32. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Ian - you avoid the point I am making, the ping pong balls are imaginary, an example - just something to indicate mixing. Assume I said pollen, or dust, or chlorine. If the atmosphere was completely mixed - there would be these indicators in equal concentrations everywhere. Clouds are an indicator of mixing in the atmosphere - and they show that the atmosphere is not well mixed.
  33. Could CFCs be causing global warming?
    Doug Cannon, the water vapour cause/effect relation is not with CO2 but with temperature and is well established from both basic physics and observations in the atmosphere. The magnitude of the effects is "just" radiation physics, not much uncertainty on this. On the contrary, clouds are still a weak point both for basic physics and observations. And this was the topic of Spencer talk at the AGU meeting. What i found most interesting is the (tentative) use of correlation to separate the "internal radiative forcing" (in Spencer words) from the feedback; but then it's necesessary to discriminate between the different types of clouds which has not been done. Anyway, good science and new ideas from anyone are always welcome.
  34. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm said:
    the clouds could be made of helium filled ping-pong balls for my argument. If the atmosphere was completely mixed we would be seeing these ping pong balls (clouds) everywhere in the sky.
    Have you ever filled a balloon with helium and let it go? Please tell me what your engineering experience tells you. Will it fall to the ground, remain at head height or quickly rise into the sky and disappear from sight in the heavens? Any engineer worthy of the name should understand simple density.
  35. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Jim - I am only using clouds as an "indicator" of mixing - the clouds could be made of helium filled ping-pong balls for my argument. If the atmosphere was completely mixed we would be seeing these ping pong balls (clouds) everywhere in the sky with a 3% or less variance (as is reported for CO2). But we don't see clouds everywhere - we can agree to that I hope. So why would we expect CO2 to be so evenly spread out through the atmosphere? Something is amiss and I suspect it is the actual CO2 data which comes from so few actual CO2 samples, relatively speaking. In my estimation there are undiscovered CO2 cool spots laying about which may balance out reported rises in CO2.
  36. Could CFCs be causing global warming?
    Riccardo, Yes, I'm aware of the water vapor/temperature relationship. I'm also familiar with Dessler's work to which you referred. By "unproven" I refer to the direct cause and effect relationship to CO2 in the models and it's magnitude. I found it interesting that Dessler invited the Spencer paper at the AGU conference in SF. It's good that those on both sides of the issue agree it's an important one to debate.
  37. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm wrote @18: I think the idea that CO2 is diffused evenly througout the atmosphere is bogus. If that were true then all molecules of any type would be equally distributed - including clouds. Ralph, as an engineer are you not familiar with the concept that temperature falls with altitude, thus limiting the amount of water vapour in the atmosphere as altitude increases? (Look up terms: lapse rate, moist adiabat, relative and absolute humidity, condensation) There is no such limitation on the mixing of CO2.
  38. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    I assume clouds are water vapor - dense "clouds" of water "molecules". If the atmosphere was completely mixed then "clouds" would appear uniformly in all the sky. And the high concentration of CO2 over the Antarctica is really puzzling - it makes me skeptical when I see data that does not fit one's common sense. I thought all this CO2 was supposed to be coming from blast factories - I doubt penguins have mastered that technology.
  39. Could CFCs be causing global warming?
    Doug Cannon, it's hardly unproven that water vapour content depends on temperature. But you know, scientist always like to go back and check in any different situation. Here you'll find some general discussion on water vapour feedback while here you can find a list of scientific papers.
  40. What ended the Little Ice Age?
    As you are probably already aware, Prof. Svalgaard disputes that the sun actually has "warmed" up in the last few hundred years. http://www.leif.org/research/Seminar-SPRG-2008.pdf Not sure what this means to the early warming from the LIA, but something?
  41. Could CFCs be causing global warming?
    I agree with the concept of looking to the physics of CFC radiation forcing and that concept certainly supports the idea that Lu's conclusion is at least premature if not totally wrong. However, we also have to realize that the physics of CO2 radiation forcing doesn't support the results in the IPCC's models either. The majority of the forcing is due to a presumed, but unproven, amplification from water vapor/clouds. It seems the issue of these secondary effects of CO2 lie at the heart of IPCC model credibility. Other than Spencer's latest, I don't see recent evidence of anyone really getting to the meat of this issue.
  42. It's a 1500 year cycle
    Anyone interested in how a cyclical signal should be detected may want to read this short and nice explanation. And those who think that a natural cycle is superimposed on a linear trend may want to read this.
  43. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Ralph, it is not necessary for satellite measurements to be calibrated against a huge number of ground stations, for the same reason that thermometers to stick under human tongues do not need to be calibrated against a huge number of human tongues. The size and type of sample needed for calibration of any instrument is properly determined by combination of observation with statistics about those observations. That's what's done with satellite measurements. An engineer should know that.
  44. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    As for clouds - I think the clouds indicate the LACK of uniformity of density in the atmosphere since they show visually how different the atmosphere can be - regardless of whether you consider water a molecule or not (it is)
    Well, Ralph, a glass of water is not a molecule. A raindrop is not a molecule. The droplets of water or bits of ice that make up a cloud are not molecules. That's just fact, Ralph. As far as the number of sensors needed to accurately sample CO2 in the atmosphere, you flat-out don't know what you're talking about in this case, either.
  45. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    Bern - I don't think a satellite actually measures CO2 and certainly not throughout the column. It is more that they measure something else then calibrate those readings with ground station CO2 readings. So if the ground stations are limited so will the satellite data be limited. And the NASA map indicates only some final averaging of data - the highest CO2 values over Antarctica, Peru and Morocco me skeptical. As an Engineer I would like to see widespread, actual measurements throughout the air column around the globe before I make a judgement about the state of CO2. Satellites are cute - but I am not convinced that they are providing sufficient data to base climate models.
  46. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    ralphiegm @ 27: no, we don't need millions of data sensors to get a handle on the total weight of CO2 in the atmosphere. We need millions of measurements by a sensor that moves around and covers the entire globe. Like a satellite in a polar orbit. That's how that NASA map you linked was produced. AIRS returns more than three million measurements per day, according to http://airs.jpl.nasa.gov/story_archive/Measuring_CO2_from_Space/Measurement_to_Science/ There's also a comment on that page: "...carbon dioxide concentrations turn out to vary by two to four parts per million. 'Before AIRS everyone thought carbon dioxide was well mixed above the boundary layer. We found that it is not.' It can vary by nearly a percent." So to you & I, CO2 is pretty evenly distributed. To scientists, a difference of a percent is quite significant - thus the choice of a scale for the graph that *highlights* that small variation. I thought it was interesting to note the comment further down about the coal-fired power plants on the Australian east coast being one of two major CO2 sources in the southern hemisphere, the other being a coal-to-liquids plant in South Africa that is the world's biggest single source of CO2.
  47. Was there a Medieval Warm Period?
    The Wikipedia item gives a link to a pdf of the Science article: http://www.meteo.psu.edu/~mann/shared/articles/MannetalScience09.pdf . The Supplementary Information can be obtained from the Science website for those who want to read the full details and methodology.
    Response: Thanks for the link to the full PDF of the paper - I've updated the link in this blog post as well as in the page addressing the skeptic argument: "Medieval Warm Period was warmer".
  48. What ended the Little Ice Age?
    re From Peru: if there's one thing I've learned in my reading on climate, it's that responses to changes in forcing are very non-uniform across the globe. Ocean currents, in particular, can result in some counter-intuitive results (like some areas actually cooling when everywhere else heats up). Your comment re Black Carbon, though, is interesting (as it's toward the end of the LIA when fossil fuel burning really took off, so it could be a factor). I'm not sure if John has already addressed this anywhere, but I did note that the graphs above start at 1890, though warming began around 1850. It does still help to reinforce the notion of sensitivity to forcing, though.
  49. What ended the Little Ice Age?
    Here something is missing: the 1910s-1940s warming is evident only in the Northern Hemisphere and there the pattern is strongest over the Artic. If the forcing is global, like Volcano+Solar, the pattern should be evident in both Hemispheres. This is not the case, so something else might have done it. I guess that the forcing in question is Antropogenic Aerosols. Important to note that the Meehl 2004 paper ignores Black Carbon forcing. This is an important flaw, as BC is now recognized as the second strongest warming forcing, only superated by CO2.
  50. Is the airborne fraction of anthropogenic CO2 emissions increasing?
    I'll certainly take your advice but I will see if there is any one that agrees with my assessment.

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