Recent Comments
Prev 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 Next
Comments 125751 to 125800:
-
Riccardo at 20:27 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
I'm sure ralphiegm very well knows that almost all the instruments around the world need to be calibrated, just a few exception. As an engeneer he's also able to read a graph and understand the meaning of numbers and he also knows that almost all measurements are indirect throgh some physical effect. There's more in what he say that is contradictory but just this shows that he's trying to fool people. This site is to talk about science and there's no point to discuss with one with such an attitude; WUWT would be a better choice. -
yocta at 17:59 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
I see what you are getting at...but what you are talking about doesn't discredit at all that atmospheric CO2 concentrations have been increasing in recent years or our ability to detect it. The NASA AIRS CO2 map which on the scale had it from about 364 to 382 ppm showed the distribution of the CO2 in the atmosphere at a particular date. I only just saw this but it is pretty amazing. The variation that got climate scientists so excited is only of the order of 1% in the "concentration of mid-tropospheric carbon dioxide". (I myself would have been frowning if it was on the order of 20% as long term trends would be difficult to compare,but it is not) Watch the video here over different months: http://svs.gsfc.nasa.gov/vis/a000000/a003500/a003562/index.html You are correct in asserting that CO2 is not as well mixed in the atmosphere as previously thought (1%variation) but I cannot see how you would infer that the satellite measurements are unreliable, or discredit the long term trends in atmospheric CO2 concentrations. Chahine et al 2008 has used the satellite derived CO2 data track weather patterns. Which is fantastic as we see an even better picture of how CO2 moves around the globe through sources and sinks and "mixes" as other people have been saying! Satellite remote sounding of mid-tropospheric CO2 Chahine et al 2008 http://www.ess.uci.edu/~jranders/Paperpdfs/2008GRLChahineetalAIRSCO2.pdf -
Bern at 17:58 PM on 6 January 2010What ended the Little Ice Age?
batsvensson: the natural variation is very large - look at the range of daily temperatures, and look at the variation from day to day, week to week, season to season. The sensitivity being discussed here is about the climate, which is pretty much defined as long-term average conditions. If you're considering an analogy of a signal varying about a centre (as I understand your comment), then, yes, the radiative forcing is affecting the position of that centre, and the sensitivity is the amount of change of that centre when subject to a given radiative forcing. The variability about that centre may stay the same, or it may shrink, or increase, quite separately from the shift in the centre. As I understand it, that's where climatology varies from meteorology - climatology concentrates on the centre, while meteorology looks at the day-to-day variation about the centre. They are quite different aspects of temperature. Weather forecasts are rarely given beyond a few days to a week, and the accuracy falls off dramatically the further out you go - primarily because weather seems to be a chaotic system with almost unpredictable behaviour. But when you look at longer term averages, that unpredictable variation is smoothed out, and we're dealing with much more predictable systems - heat comes in, heat goes out, the difference says what the long-term temperature average will be. The hard part that seems to be occupying climatologists' time now is figuring out exactly *where* heat goes - the satellite measurements seem to clearly indicate that heat is being retained by the earth - and what effects that will have, in terms of sea levels & potential weather patterns (which will both determine whether that beach-front property was a good long-term investment or not). -
ralphiegm at 16:29 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
"Significant Findings from AIRS Data 'Carbon dioxide is not homogeneous in the mid-troposphere; previously it was thought to be well-mixed 'The distribution of carbon dioxide in the mid-troposphere is strongly influenced by large-scale circulations such as the mid-latitude jet streams and by synoptic weather systems, most notably in the summer hemisphere 'There are significant differences between simulated and observed CO2 abundance outside of the tropics, raising questions about the transport pathways between the lower and upper troposphere in current models 'Zonal transport in the southern hemisphere shows the complexity of its carbon cycle and needs further study" Yocta - I have been saying that CO2 is not well mixed in the atmosphere. I have been getting rebuked here for that position. But the AIRS scientists agree with me judging from their notes I pasted above. I expect that after many, many years of this remote sensing we may finally find get a handle on the global mass of CO2 and whether it is actually rising over time. I am happy to wait till the data is perfected. -
yocta at 15:33 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
RE: ralphiegm post 62 The same historical article you referenced continues to chart the need for future satellites to complement and add to the existing data away from the middle troposphere not because AIRS is no good. ralphiegm:...This device is not measuring CO2 - it is measuring infrared light and "calibrating" it in the lab back on earth... By “ground station” I am to understand that you just mean it as a place to process the raw data downloaded from the satellite. The AIRS people are not calibrating the data with anything. The mixing ratio of trace gases in the atmosphere is directly calculated from the data from the AIRS data (Chahine et al 2006 page 921) . This is then checked against other independent detection systems including a ground based FTR and aircraft flask measurements. This paper also links to the details of how the mixing ratios are calculated from specta, and links to others (i’m hoping you have access?) Chahine et al 2006 http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/40298/1/05-0324.pdf ralphiegm:...You imply the device is a spectrograph...fancy calibrating. It is a spectrograph and it happens to be sensitive to IR radiation. It doesn’t matter if it is 830 miles away as long as it has a lens capable of resolving it at that distance (think Hubble or other IR astronomical devices that can measure spectra from interplanetary bodies). It has been pre-calibrated on earth by NIST, which is about as fancy as you can get. Then the accuracy and sensitivity was tested again to better than 1 part in 105 and is tested regularly for drift and long term stability whilst in flight. The only calibration is done on the equipment before flight. Chahine et al 2006 continue to state: The radiometric accuracy and stability of AIRS radiances has been confirmed by several fundamentally different types of comparisons, including 1) the results of the daily measurements of sea surface temperature (SST), 2) direct spectral radiance comparisons from aircraft observations, and 3) low temperature surface radiances from Antarctica. This paper is pretty good, it also deals with the cloud cover issue you were raising. -
ralphiegm at 14:36 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
Ian - as to your thermometer analogy - try reading the thing 830 miles away with an infrared detector. -
ralphiegm at 14:12 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
Ian - if you check how a satellite measures CO2 you will begin to see the pitfalls: Clouds, ground reflections, wind, water vapor, atmospheric pressure, strata, turbulence, aerosols. It is not perfected by any stretch. And since the clouds appear more frequently over the southern hemi and the ocean the CO2 from those areas are not as well represented. I think the current data is too weak to make sweeping judgments about the fate of the planet. And Gordon - the 200 ground stations actually represent 1 million square miles of area per ground station. And that is just one strata. That may be enough data for you but NASA thinks we need a lot more CO2 data and so do I (they are trying to get a new satellite up there that works - and new data coming soon anticipates that the atmosphere is not well mixed at all - as I have said). Some folks wanna jump the gun on CO2 - I'd rather wait until there was real data synched with temperature and land use. What's the hurry? Gordon - -
Gordon1368 at 13:51 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
Ii don't understand how 200 or 300 stations are not enough to show whether CO2 is evenly mixed. If that many stations, located around the world, show consistency over time, what is the likelihood that another station, or another million stations, will show mixing, or any kind of inconsistent distribution? Furthermore, if you want me to accept clouds as an appropriate comparison, you will have to explain to me how the stationary stations do not show significant variation over any time period. You know,the way my eyes measure the presence of clouds in the morning, and their absence in the afternoon, although i have hardly changed my position? Soory, if there was any significant mixing, and wind effect, even a single station could reveal that. -
Ian Forrester at 13:45 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
Ralphiegm said:This device is not measuring CO2 - it is measuring infrared light and "calibrating" it in the lab back on earth.
So you don't believe in liquid in glass thermometers since they don't measure "temperature" but measure changes in volume of a liquid which are then "calibrated in the lab"? You have obviously never worked in, or have knowledge of what goes on in an analytical lab. Nothing actually measures what they are reporting but measure some proxy which is then, through calibration and running of standards, converted to actual measurement of the material in question. -
ralphiegm at 12:52 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
"What AIRS does is measure the infrared light emitted by carbon dioxide molecules. Carbon dioxide in the air absorbs infrared emitted by the surface, and then re-radiates it at a slightly lower energy level (which is why it acts as a greenhouse gas). The exact frequency that gets emitted depends on temperature. So Chahine can take the infrared data AIRS sends back to Earth and use a mathematical inversion process to turn it into temperatures." I think the above quote from the NASA website http://airs.jpl.nasa.gov/story_archive/Measuring_CO2_from_Space/Measurement_to_Science/ explains my concern. This device is not measuring CO2 - it is measuring infrared light and "calibrating" it in the lab back on earth, which I assume, is a ground station (what else could it be?) In fact, NASA is trying to send more satellites up to see if they can measure CO2 - if the AIRS was so good why do we need another one? My guess because it is not so good. You imply the device is a spectrograph but it sounds like something else - but whatever it is - it would take some fancy calibrating to assure me that it is reading accurately the CO2 variations in the air column or reading the total weight of CO2 in the air column. -
Marcus at 12:33 PM on 6 January 2010It's the sun
If it was only the troposphere & near-surface that was showing warming, then I might-just might-be prepared to accept that something other than GHG was the cause of the last half-century of global warming. What concerns me, though, is that the Stratosphere has been COOLING over that same period of time (minus a few spikes due to a few huge volcanic eruptions). If the sun were the cause of the warming, then the warming would be spread throughout the entire atmosphere, yet instead the warming simply *stops* at the tropospheric level. This suggests that long-wave radiation is being trapped in the troposphere by.....Greenhouse gases! -
yocta at 12:06 PM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
In keeping with the site’s ethos I’ll make sure to keep to the science in my comments. RE:# Ralphiegm commment 59 ralphiegm: And there is no "global" data back from those satellites yet. So how can you use that argument against my position? I am bringing to your attention that there are satellites launched with the primary purpose to measure and map CO2 more effectively, and, as a bonus, the measurements it has performed are consistent with what is known of the atmosphere. ralphiegm: You make it seem as though all these climate scientists have accurate satellite data on CO2 for years. NASAs Aqua satellite launched in 2002 has an Atmospheric Infrared Sensor onboard. This is one of 6 instruments on board the satellite but given it is a highly accurate infrared spectrograph it makes a very handy tool for measuring CO2 concentrations in the atmosphere, and I believe across different altitudes. Just because the satellite wasn’t primarily designed to measure CO2 concentrations (like GOSAT and the unfortunate NASA one that crashed) doesn’t make it ineffective at all or mean that climate scientists have never had satellite data to use. AIRS http://airs.jpl.nasa.gov/AIRS_CO2_Data/About_AIRS_CO2_Data/ See John’s post on how the earlier IRIS satellite from 1970 and the Japanese IMG Satellite in 1996 was used in comparison with AIRS. There is also a good paper that discusses the results (Harries 2001). http://www.skepticalscience.com/empirical-evidence-for-global-warming.htm ralphiegm : As you may know satellites do not measure CO2. They try to measure CO2 but must be calibrated from - you guessed it - ground stations. This is where I am confused by what you mean. AIRS has a spectrograph on board. It measures the spectrum of CO2 directly and hence the concentration. It was calibrated prior to its flight through the National Institute of Standards and Technology (NIST) which in metrology is the appropriate thing to do. Prelaunch and in-flight radiometric calibration of the Atmospheric Infrared Sounder (AIRS) http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1196044&tag=1 I am assuming when you say ground stations you mean ones that are used already to measure atmospheric CO2. Please tell me (with links perhaps) as to why you believe the Satellite data is calibrated from ground stations? -
ralphiegm at 11:28 AM on 6 January 2010Is the airborne fraction of anthropogenic CO2 emissions increasing?
dhogaza - I am not aware of a model that accounts for wind but maybe there is one out there. I have never seen wind, clouds or air turbulence mentioned in any of the many papers I have read on climate studies. I could be wrong but if you can point out to me that someone, somewhere has considered wind in their model I would happily read about such a model and report back to you - if you can find one. Good luck trying - I gave up looking. And the reason why wind is not considered is the same reason why clouds are not considered in climate models - it's beyond human ability to model the world. Its just too complicated. -
ralphiegm at 11:16 AM on 6 January 2010Is 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? -
dhogaza at 11:00 AM on 6 January 2010Is 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. -
Ian Forrester at 10:51 AM on 6 January 2010Is 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. -
yocta at 09:59 AM on 6 January 2010Is 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 -
ralphiegm at 09:30 AM on 6 January 2010Is 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). -
Ian Forrester at 07:56 AM on 6 January 2010Is 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. -
RSVP at 07:55 AM on 6 January 2010What 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. -
Riccardo at 06:36 AM on 6 January 2010Predicting 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. -
ralphiegm at 06:32 AM on 6 January 2010Is 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. -
Riccardo at 05:48 AM on 6 January 2010Is 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. -
Riccardo at 05:12 AM on 6 January 2010Is 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. -
ralphiegm at 04:33 AM on 6 January 2010Is 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? -
Jim Eager at 03:55 AM on 6 January 2010Is 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. -
rajpe at 02:21 AM on 6 January 2010Predicting 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". -
ralphiegm at 01:19 AM on 6 January 2010Is 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. -
TerryG at 00:25 AM on 6 January 2010Is 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. -
Catprog at 00:21 AM on 6 January 2010Is 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. -
batsvensson at 18:20 PM on 5 January 2010What 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. -
ralphiegm at 14:44 PM on 5 January 2010What 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. -
ralphiegm at 14:22 PM on 5 January 2010What 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". -
thingadonta at 12:39 PM on 5 January 2010What 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. -
ralphiegm at 12:09 PM on 5 January 2010Is 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. -
Doug Cannon at 11:47 AM on 5 January 2010Could 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. -
Riccardo at 11:34 AM on 5 January 2010Is 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. -
ralphiegm at 11:14 AM on 5 January 2010Is 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. -
Jim Eager at 11:05 AM on 5 January 2010Is 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. -
djb95054 at 10:41 AM on 5 January 2010It'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. -
Riccardo at 10:21 AM on 5 January 2010What 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). -
Jim Eager at 10:18 AM on 5 January 2010Is 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. -
yocta at 10:16 AM on 5 January 2010Is 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. -
Riccardo at 09:58 AM on 5 January 2010Is 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. -
ralphiegm at 09:45 AM on 5 January 2010Is 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. -
Riccardo at 09:35 AM on 5 January 2010Could 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. -
Ian Forrester at 09:34 AM on 5 January 2010Is 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. -
ralphiegm at 08:52 AM on 5 January 2010Is 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. -
Doug Cannon at 08:27 AM on 5 January 2010Could 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. -
Jim Eager at 08:20 AM on 5 January 2010Is 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.
Prev 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 Next