Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings

All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  2564  2565  2566  2567  2568  2569  2570  2571  2572  2573  2574  2575  2576  2577  2578  2579  Next

Comments 128551 to 128600:

  1. Philippe Chantreau at 11:11 AM on 18 October 2009
    How we know global warming is still happening
    The "unlikely" part is entirely your opinion. Scientists studying the question, such as Trenberth and Fasullo don't find it so unlikely. The only physical reason to expect increased nebulosity is a constant relative humidity and even that is not entirely certain. If relative humidity shows a slight decrease, who knows?
  2. Empirical evidence that humans are causing global warming
    Thumb, "this sounds like me saying my stove top surface actually cools because it's loosing energy as it radiates heat." That is pretty much a correct observation otherwise you stove would melt pretty soon. If something radiates energy, then it is a cooling phenomena per definition.
  3. Are humans too insignificant to affect global climate?
    Thank you for a well-designed, thoughtful and informative website. In particular I REALLY appreciate the links to the primary literature (e.g., Ghosh 2003), which is often hard for non-specialists to find. Please keep it up! Andrew (a practicing ecologist) P.S: Regarding comment #26. There is nothing wrong with the Y-axis scale used in Figure 1, as it fairly represents the variability in the observed data. Plotting from a zero origin would be meaningless unless one wanted to minimize the visual impact of the trend.
  4. How we know global warming is still happening
    Yes, Philippe I agree that **if** on assumes that all changes in overall cloudiness are a result of a feedback on temperature change, then recent history would tend to argue for positive cloud feedback. However, there is no reason that all recent changes in clouds are a result of feedbacks on temperature(and this seems unlikely). There are, OTOH, some pretty good basic physical reasons for assuming that cloud cover will increase or at least stay the same in a warming climate(more condensing water available to form clouds). Cheers, :)
  5. Philippe Chantreau at 02:59 AM on 18 October 2009
    Empirical evidence that humans are causing global warming
    International Arctic Research Center? What the heck is that now? Is it the name D'Aleo gives his site these days? Seems to imply it's doing real research so I would have expected better than a blog post. On the other hand, looking at Cryosphere Today, we see that the current global sea ice anomaly is about -1.75 million sq km. The last time that there was a positive anomaly of comparable magnitude was late 1988. http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg
  6. Empirical evidence that humans are causing global warming
    Robbo the Yobbo, "Continued neglect of the obvious and the evident - is just very, very silly." I completeley agree with you, but you need to modify the claim "This is consistent with both the evidence of past multidecadal changes and the expectation of a cooling influence for 20 to 30 years form 1998" in "This is consistent with both the evidence of past multidecadal changes and an almost linear underlining trend" So yes, it's silly to neglect that decadal variability alone _cannot_ do the job. One last thing: "expectation of a cooling influence for 20 to 30 years form 1998" could you please explain? I've never heard such a claim from a scientist, apart from the blatantly misinterpreted Latif words reported across the web.
  7. Robbo the Yobbo at 15:28 PM on 17 October 2009
    Empirical evidence that humans are causing global warming
    I will link also to the International Arctic Research Centre http://icecap.us/images/uploads/RECENT_RESULTS.pdf Continued neglect of the obvious and the evident - is just very, very silly.
  8. Robbo the Yobbo at 14:04 PM on 17 October 2009
    Empirical evidence that humans are causing global warming
    Both surface temps and ocean heat content vary on annual to multidecdal (to indeed millenial plus) timescales. The Schuckmann paper shows modest warming from 2003 to 2008. However, the result is strongly dependent on the state of ENSO at start and end dates. The ocean is currently a little cooler in the information provided by the NOAA National Oceanographic Data Center (NODC). http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/ There is no strong warming evident in the past 6 years. This is consistent with both the evidence of past multidecadal changes and the expectation of a cooling influence for 20 to 30 years form 1998. There is nothing difficult or controversial in this - climate changes - and sudden climate shifts - occur naturally and obviously. This makes any climate prediction problematic and the 'radiative equilibrium' models utterly nonsensical. http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/ The radiative imbalance is not constant. Until there is a better understanding of natural variations in climate - the attribution of recent warming to AGG is pointless and misguided. The radiative equilibrium model of atmospheric physics is and always has fundamentally flawed - based as it is on a flawed assumption of solar and Earth albedo constancy. http://www.sciencedirect.com/science?_ob=ArticleURL... http://wattsupwiththat.com/2009/08/11/ocean-heat-content-and-earth%E2%80%99s-radiation-imbalance/ Use of the ohc paper by Schuckmann et al to assert continued gloabl warming is misguided.
    Response: The Douglass paper you link to looks at the planet's energy imbalance and finds it has increased from the 1970's to present:



    They argue that there's a correlation between energy imbalance and the Pacific Decadal Oscillation. But there is no causation. On the other hand, the causation between CO2 and energy imbalance is proven by multiple lines of empirical observations.

    Note, using Schuckmann to assert an energy imbalance doesn't contradict Douglass's results either - they do exactly the same thing - use ocean heat to find a positive energy imbalance.
  9. Philippe Chantreau at 10:23 AM on 17 October 2009
    How we know global warming is still happening
    The physicsworld.comn piece referenced by RSVP is not a research article but rather an opinion piece. Besides reminders that water vapor is the chief GH gas and CO2 the chief cause of recent increased GH effect, it considers water vapor feedback. It postulates that, with increased cloud cover, the WV feedback may not be as strong as current models show. However, let's not forget the information provided by your fellow skeptic Robbo. Both the Clements paper and the Trenberth and Fasullo paper that he trumpeted with great fanfare suggest decreased lower cloud cover as a feedback to enhanced GH effect. Your own reference to increased NPP in the Amazon due to increased insolation seems to agree. As I said, it may not be all that simple. Cheers.
  10. Models are unreliable
    Good science predicts the future. We know enough about biology to know that what we can to do grow more food; and we bet our lives on that...if that science let us down one year, we'd starve in our modern society that depends on optimum agriculture. We know enough about cars to know that all our cars will start and get us home tonight when we leave work. We aren't afraid as we approach other cars at alarming rates because science guarantees brakes and tires do predictable things. We know that if we dump lead into rivers the lead gets into fish and human tissue and causes terrible consequences. We can bank on this being true today as well as 1000 years from now. *That* science is done. But the science of climate modeling is certainly *not* done, at least in the minds of most people. Let's face it; we are talking very tiny numbers - .038% CO2, < 0.2 degree temperature deltas. We are asked to believe that while human emissions are small compared to natural ones, that the earth absorbs *exactly* the amount it emits, and so any tiny perturbation is a disaster. Hogwash. There was a time where the orbits of the planets were explained by invisible crystal spheres. And they have models too - ones that would even explain the retrogradation of Mars - all of which functioned using the inviolate assumption that Earth was the center of the visible universe. That premise drove the model - which, while far from elegant - was made to work. Here we are in the same situation. I have to believe that climate researchers have an agenda. People who don't believe in AGW are certainly not going to devote their lives to studying it. And so, we start with one premise - it's all our fault - and work from there. When an objection comes out - say to the magnitude of CO2 and man's contribution to that - out come the curves. Out come the crystal spheres. Out come the graphs showing tiny variations drawn on an offset scale for emphasis. Out comes a vague paper digestable by 'the community' but no one else. If you truly want people to believe that "the science is done", do some actual physical research. Create a large enclosed simulated atmosphere and show the effect of doubling CO2. Don't slip away saying it's not that simple. Science is all about reduction to experiments that *are* that comprehensible. Otherwise, the models are about as believable as those that can model old stock market data but won't make a dime.
  11. Empirical evidence that humans are causing global warming
    To me, you don't even really need to quantify the exact impact of CO2 on temperature to believe we will suffer major consequences from rising CO2. If you accept that CO2 has SOME impact on temperature (which even the most ardent skeptics do), the only thing you need to know is that CO2 is already at its highest level in 400,000 years, and probably in 15 million - and it's poised to double. There's simply no conceivable way we can pump that much CO2 into the atmosphere without SOMETHING drastic happening. Here's my Blog Action Day post, via Coby: http://scienceblogs.com/illconsidered/2009/10/blog_action_day.php
  12. Philippe Chantreau at 06:49 AM on 17 October 2009
    Are humans too insignificant to affect global climate?
    Your denialist fello must be a fan of John Daly, whose graphs feature highly compressed Y axises in order to downplay recent warming. I guess it is probably a widespread convention among some that graphs should be adjusted to show what they want to see instead of revealing what the data say.
  13. CO2 effect is saturated
    What I don't understand about this argument is that we have a clear demonstration of what high levels of CO2 can accomplish in respect to greenhouse effect with Venus. From what I understand Venu's atmosphere is over 95% CO2 and it's surface tempuratures are almost 500 degrees celcius. That makes it hotter than Mercury the closest planet to the Sun. If CO2 had a saturation point wouldn't Venus have reached it or am I totally misunderstanding the premise?
  14. Empirical evidence that humans are causing global warming
    There are two ways you can raise the water level in a lake. You can increase the flow of water from the lake's inlet, or you can decrease the drain of water through the lake's outlet. Likewise, the heat content of the climate system (atmosphere, oceans, and land) is ultimately determined by the balance between energy input (shortwave radiation from the sun) and energy output (longwave radiation from the earth out into space). CO2 in the atmosphere reduces the flux out of the system and increases the heat content of the system. Eventually, a new equilibrium is reached, where the outgoing longwave flux once again matches the incoming shortwave flux, but at a higher level of heat content of the climate system.
  15. Empirical evidence that humans are causing global warming
    If you want empiracle evidence of the saturation level of CO2 then look no further than Venus. It has an atmosphere which is over 95% CO2 and surface tempuratures are at 467 degrees celcius hotter than the surface of Mercury. Seems we still have a long way to go before reaching that saturation level.
  16. Empirical evidence that humans are causing global warming
    RSVP, I just was less patient the the other mates here; just read their replies. But to male my point clearer, i'll give you an example of one of your trivial but wrong reasoning. If you take away heat from a body, it will cool; this is the trivial part. But if you apply it to the earth surface and the atmosphere alone it's plain wrong.
  17. Empirical evidence that humans are causing global warming
    RSVP, If I read your post #4 correctly, you seem to be implying that the greenhouse effect violates the laws of thermodynamics. In your summation you said: "remember that you cant get something for nothing, because if you could, we could solve the energy crisis by simply building greenhouses in our backyards." I believe you think this way because you regard the energy emanating from the Earth's atmosphere to be the primary source. The Sun is the primary source. The flow of energy is a two way street, a net warming on average during daylight hours and a cooling at night. However, the cooling loss of energy is also occurring during the daylight hours, it is ongoing day and night. And nothing is "trapped"..bad choice of words in common usage to describing what is happening, leading to all kinds of misconceptions. The greenhouse effect isolates on the cooling aspect of this flow of energy, it does not create additional energy but rather slows down the outward flow on energy and thus the cooling tendency. A surface that cools more slowly will end up being a warmer surface.
  18. Empirical evidence that humans are causing global warming
    RSVP writes: "In general, what I have noticed in all posts is that no one is able to think for themselves. The validity of any assertion must be backed by an article, google, etc." The problem is that almost every sentence you post here is wrong. It's abundantly clear that you just don't understand even the most basic science involved. People are thus posting links to answers or explanations because they hope you will read them and learn something. It's not a blind appeal to authority by people who are "unable to think for themselves". It's an effort to help you learn something by people who are disinclined to explain the same utterly basic things over and over again when there are handy and informative explanations already written.
  19. Empirical evidence that humans are causing global warming
    WeatherRusty I used the word "trapped" as does the article. Thumb Heating and cooling mechanisms have nothing to do with whether something is subjectively perceive as being "hot" or "cold". Your CPU's heatsink might feel hot while it is actually cooling your CPU. On the other hand, a thing may be "cooling" or "heating" if the temperature is dropping or raising, but that is a different idea. Riccardo It is not clear where the line needs to be drawn for a website tuned to "Examining the science of global warming skepticism". If something is "wrong" or "trivial", please be more specific. ------------------------------------------------- In general, what I have noticed in all posts is that no one is able to think for themselves. The validity of any assertion must be backed by an article, google, etc. I remember this mentality from the schoolyard (i.e., if I didnt see it on TV, it cant be real, etc.) And more accutely is the sense that anything that appears to stray from "the consensus" is labeled as "political". Ironically, if there was perfect consensus there would be no need for further discussion, however as there is no consenus in reality, the entire discussion is nothing but political, and as such hypocritical.
  20. Comparing CO2 emissions to CO2 levels
    @Alexandre E.G Beck is a retired teacher for biology in germany. His graph makes the big mistake to compare continuous mesurements of well mixed atmosphere with historical discontinuous analysis of air in certain environments. It is obvious, that these historical data are strongly biased by environmental factors. They are taken in urban milieu which is known for higher CO2 levels. If you make some analysis of the air in any lab you will never get co2 levels as low as Mauna Loa levels. In certain cities like Paris, Berlin, London you might get levels above 1000 ppmv.
  21. Empirical evidence that humans are causing global warming
    "Whatever energy is radiated into the atmosphere by the surface of the Earth, whether by sea or land, represents a LOSS of energy from the surface. There is no radiative heating of CO2 without cooling of the Earth's surface." I suppose this could make sense if there was no sun adding to the mix, but otherwise this sounds like me saying my stove top surface actually cools because it's loosing energy as it radiates heat.
  22. CO2 effect is saturated
    I suppose it's also possible that the satellites were in more-or-less low equatorial orbits, were thus only measuring the tropics, and the tropics have seen the least surface warming. Ok, I'm out of ideas for the moment.
  23. CO2 effect is saturated
    My apologies for what is in effect a repost, but I asked this question at the bottom of a second page of comments where I first saw this diagram. Here I can be first :-) (and I think it's a relatively important question) There is one thing that bothers me about figure 1 (the differential spectrum). The decreased emission in certain absorption bands makes perfect sense. But it's a fact of the (surface) instrumental record that the planet was (a little) warmer in 1996 than in 1970 (somewhere in the 0.1 to 0.2C range). So shouldn't the flat parts of the differential spectrum be just a bit above zero? I suppose it's possible due to different instruments (i.e. different satellites) that they had to normalize, but it would have been so much better if they didn't. Does anyone have the answer?
  24. Empirical evidence that humans are causing global warming
    Good post. Skeptics might counter with "ok, so humans cause some global warming, but not very much". A next logical progression is to discuss climate feedbacks and why the net feedback is almost certainly positive.
    Response: Funny you should mention that, the next post on climate sensitivity is on that very subject.
  25. How do we know CO2 is causing warming?
    There is one thing that bothers me about figure 1 (the differential spectrum). The decreased emission in certain absorption bands makes perfect sense. But it's a fact of the (surface) instrumental record that the planet was (a little) warmer in 1996 than in 1970 (somewhere in the 0.1 to 0.2C range). So shouldn't the flat parts of the differential spectrum be just a bit above zero?
  26. Is Antarctic ice melting or growing?
    Mizimi - " It is only because it is useful for our mathematical purposes that we lump all those variations into an 'annual mean variation' " Somewhat aside from my point; anyway, different ecosystems are not scattered about at random, so there must be some real tendencies in the factors that affect ecosystems (like rainfall).
  27. Are humans too insignificant to affect global climate?
    Leisureguy, tell your friend to reverse the axis to "demonstrate" a huge drop in CO2. Seriously, if one can not read a graph should not even try. Expanding the axis means let people see and judge. On the contrary, putting the origin of the y axis to zero means mask what people could (or should) read.
  28. Are humans too insignificant to affect global climate?
    %26 To have denialists complain about misleading chart axes is a bit rich. But this complaint is silly in its own right. Changing the origin to 0 would change (and "exaggerate") nothing else except that the graph would now sit half way up the axis. The difference between 275ppm and the present level is still 110ppm or so. It is quite a common graphical convention, when the low points are well above zero, to have the y axis starting at an appropriate level.
  29. How we know global warming is still happening
    Philippe, if the temperature dew point spread is unchanged and air cools the same amount (in degrees C) from a warmer maximum, then it will condense more water based on the Clausius-Clapeyron relationship(which is the basis of the assumption of constant RH). More water condensing should lead to more cloud IMO. This idea is not in contradiction with the other papers I have posted IMO, for the simple reason that it is hightly likely that other things than the **feedback** process I outline above influence cloudiness(on regional and global scales). This is really no different from allowing that we can have a period of cooler(or falt temperature) years, even while ever stronger CO2 feedback is (supposed to be) heating the climate. Something besides the feedback I have mentioned, may be forcing the clouds and, hence, obscuring the feedback signal. As for substantiation, I don't think it is at all difficult to find people supporting the idea that cloud feedback is negative. ROy Spencer is one prominent example. I suppose I can find a specific paper. IAC, RSVP quoted a paper above(which I haven't read yet) and I have just been laying out what I presume to be the theoretical underpinnings of their conclusion(I haven't read the paper yet). Cheers, :)
  30. Are humans too insignificant to affect global climate?
    Regarding the first chart: a denialist I correspond with violently objects to this chart: the left axis begins at 250, rather than 0, which greatly exaggerates the increase. Either give us a chart which starts at 0, or indicate with a jagged line that the Y-axis starts way up the scale. That will end that argument, I hope.
  31. Philippe Chantreau at 04:19 AM on 16 October 2009
    Comparing CO2 emissions to CO2 levels
    Actually no, E&E is not peer reviewed. Papers are submitted to the the editor, Sonja Boehmer-Christiansen, who then decides what gets published. Her own record of publications is extremely scant at best: I believe that around 4 papers were found in one of the largest database of science publications, mostly all elaborating on the same topic, and only marginally related to natural sciences. She also has a history of sympathy toward anti-evolution/creationist ideas. Someone posted a link in this blog to more info, but I can't recall in which thread at the moment. The journal has a self proclaimed vocation of offering a "platform" to "authors" critical or skeptical of AGW and that seems to be the only consistent criterion for selecting papers. E&E is by no means a reliable or even interesting source for any kind of scientific research. People who do real science and research do not even know of its existence. The ideal venue for Beck, really. I am not sure whether or not he actually published in it. Perhaps even Sonja B-C could not bring herself to pass such doctored graphs as the one mentioned by Ned. The trick is so thick that it wouldn't fool a junior high student, yet Beck seems to find it perfectly fine. Don't waste your time on stuff with which even McIntyre wouldn't compromise himself.
  32. Comparing CO2 emissions to CO2 levels
    Shawnhet - thank you for the link Ned - Thank you for the information. I agree with you about those claims being "ridiculous". the reason of my question was that I´d like to find something easy to understand at-a-glance, that could reach a denier´s mind. That paragraph you pasted is very interesting, and puts in perspective the wild claims that CO2 varied like crazy in the 19th century. But the link is not something that makes clear who´s saying that. A denier could say that it´s made-up. Maybe there´s a published paper confirming the stability of gases trapped in ice cores over long periods of time? Or some more official website (like the University´s) with that letter from Keeling? Philippe - Of course it´s a crock. But people cling to that kind of stuff. By the way, Energy & Environment is peer reviewed, right? even if it´s crap...
  33. Empirical evidence that humans are causing global warming
    RSVP Your questions seem to go to basic climate physics, electromagnetic radiation, light - energy, blackbody radiation, and greenhouse gas IR absorption - emission. I suggest that you read David Archer's excellent book, Global Warming - Understanding the Forecast to get a solid grounding in climate physics. The book is actually a text used at the University of Chicago for non-science majors. It is very readable and will help you understand what climate models do. Since Archer presents the subject in a systematic way, it will be easier to understand than a series of Q&As from a number of Skeptical Science readers. In addition to the book, Archer provides videos of his U of Chicago lectures and access to 8 on-line models. I've posted about Archer's book at this link.
  34. Empirical evidence that humans are causing global warming
    John, Yet another outstanding post. I will also be referring to the Wang 2009 article on my site. I have been using you as a source more and more frequently. BTW, I hope you do not mind but I have referred readers over at WUWT to your site quite a bit lately. :) You are doing a tremendous service to the general public!
  35. Empirical evidence that humans are causing global warming
    "Whatever energy is radiated into the atmosphere by the surface of the Earth, whether by sea or land, represents a LOSS of energy from the surface. There is no radiative heating of CO2 without cooling of the Earth's surface." I suppose this could make sense if there was no sun adding to the mix, but otherwise this sounds like me saying my stove top surface actually cools because it's loosing energy as it radiates heat.
  36. How do we know CO2 is causing warming?
    I don't see the point with the Pielke references, as Evans & Puckrin (2006, link is given above just after the Philipona paper) show that the change in DLR reported by Philipona et al. is caused by greenhouse gases.
  37. Empirical evidence that humans are causing global warming
    RSVP, You are having a problem with visualizing how the greenhouse effect works. Energy is not "trapped" by the greenhouse effect, the flow of energy is continuous but slowed in the outward direction. The surface is warmer with a greenhouse effect because it looses energy to space more slowly. The atmosphere is like the lithosphere or crust of the Earth in that the very high heat just several miles below Earth's surface only very, very slowly is allowed to escape the Earth's interior. Just think of how much cooler the Earth's interior or the interior of the Sun would be if the overlying matter were not opaque to outgoing radiation.
  38. Empirical evidence that humans are causing global warming
    RSVP, your comment did the impossible, being at the same time trivial and wrong. For sure you completely lack the concept of energy balance, which is (should be?) indeed trivial. I don't think this blog should be involved in such high school level, or maybe even common sense, discussions or teaching.
  39. Philippe Chantreau at 00:01 AM on 16 October 2009
    Comparing CO2 emissions to CO2 levels
    Beck rearing his ugly head again. Beck does not have any paper. He does not publish in real science journals. His "work" is irrelevant to any discussion of science.
  40. Empirical evidence that humans are causing global warming
    Whatever energy is radiated into the atmosphere by the surface of the Earth, whether by sea or land, represents a LOSS of energy from the surface. There is no radiative heating of CO2 without cooling of the Earth's surface. Any radiative energy that returns to the Earth from the atmosphere (having originated from the surface), would warm the surface, but at the same time be associated with equal COOLING of the atmosphere. This energy has essentially been reflected or could be considered as if it never left the surface in the first place. In terms of this type of accounting, the energy cannot be in two places at once. It is either on the surface or in the atmosphere. As a result, globally speaking, it does not seem possible for there to be a net positive offset DIRECLTY related to the operation of these radiative mechanisms. However, the portion of energy that is "trapped", due to reflection as described, would seem to accumulate, and cool through either conductive or convective mechanisms. Those which caused the air to warm would now depend ironically on greenhouse gases for expelling this additional energy. For those that may think this explanation is oversimplified, please take a look again at the diagram of the Earth's atmosphere, and remember that you cant get something for nothing, because if you could, we could solve the energy crisis by simply building greenhouses in our backyards. My last thought would also be to consider the temperature on the Moon's lightened surface, which has absolutely no atmosphere at all.
  41. Comparing CO2 emissions to CO2 levels
    "a cyclic patters" should obviously be "a cyclic pattern". Apologies for the typo.
  42. Comparing CO2 emissions to CO2 levels
    shawnhet writes: "Alexandre - here are some publications to Beck's papers. [...] Personally, I don't know what to make of them." E.G. Beck's claims are simply ridiculous. On CO2 measurement, he apparently thinks that the atmosphere used to show immense (unphysical) swings in CO2 that suddenly stopped just when we developed a more accurate method for measuring CO2: http://scienceblogs.com/deltoid/2006/10/more_nonsense_about_co2.php http://scienceblogs.com/deltoid/2008/03/remember_eg_becks_dodgy.php Ralph Keeling noted the absurd implications of Beck's supposed record of atmospheric CO2 from unreliable chemical measurement data: ============= "It should be added that Beck’s analysis also runs afoul of a basic accounting problem. Beck’s 11–year averages show large swings, including an increase from 310 to 420 ppm between 1920 and 1945 (Beck’s Figure 11). To drive an increase of this magnitude globally requires the release of 233 billion metric tons of C to the atmosphere. The amount is equivalent to more than a third of all the carbon contained in land plants globally. Other CO2 swings noted by Beck require similarly large releases or uptakes. To make a credible case, Beck would have needed to offer evidence for losses or gains of carbon of this magnitude from somewhere. He offered none." http://www.biokurs.de/treibhaus/180CO2/Response-Beck-by-R-Keeling-2.doc ======== Beck also makes completely unjustifiable claims about cyclic patterns in temperatures at the millennial scale. Check out this graph, where Beck plots a cyclic patters that supposedly represents a fluctuating climate signal ... but weirdly enough, the cycle continues smoothly across a discontinuity (and scale change!) in the X-axis of the graph: http://www.realclimate.org/index.php/archives/2007/06/curve-manipulation-lesson-2/ http://scienceblogs.com/deltoid/2007/06/another_dodgy_graph_from_eg_be.php#more There is a reason why, for example, Steve McIntyre refuses to allow discussion of Beck's work on ClimateAudit. Lending any credence to that kind of nonsense is probably the fastest way to demolish your own credibility.
  43. Empirical evidence that humans are causing global warming
    Sorry, I should have listed A Saturated Gassy Argument second. Your first stop, Paul, should be right here at Skeptical Science: Is the CO2 Effect Saturated?. If you need more convincing after that, click on the links in my comment immediately above this one.
  44. Empirical evidence that humans are causing global warming
    Paul, saturation has not been reached. See A Saturated Gassy Argument at RealClimate. That link is to Part I, but there is also a Part II.
  45. Empirical evidence that humans are causing global warming
    The only problem with this analysis is that beyond certain levels the carbon dioxide level gets saturated and very little extra warming occurs. Most of the climatologists I've consulted agree with this; it's just a question of at what level warming stops. Many sources seem to agree that 200 ppm sees the most warming; after that, warming declines and eventually becomes minimal. At 400 ppm, we've almost certainly reached the point of effective saturation, which might explain why the planet hasn't warmed in a decade.
    Response: I suggest you read through the post again. Two points to look for. One, the CO2 effect is not saturated because we're observing an enhanced greenhouse effect. The logarithmic relationship between CO2 and temperature has been confirmed by empirical observations. Secondly, don't be misled by erroneous arguments like 'global warming stopped in 1998'. The planet is still accumulating heat. Satellite measurements show more energy coming in than escaping back out to space. We have been warming over the last decade.
  46. pekka.lehtikoski at 11:47 AM on 15 October 2009
    Humans are too insignificant to affect global climate
    It would be interesting to have atmospheric CO2 and human emitted global carbon emissions plotted in same graph with time scale of last 200 years.
    Response: This is done in Comparing CO2 emissions to CO2 levels.
  47. pekka.lehtikoski at 09:58 AM on 15 October 2009
    A broader view of sea level rise
    Thank you for your comment. Yes, I meant the notion that humans, are causing global warming, and specifically by burning fossil fuels. First disclaimer, I am no expert, but only trying to learn. My problem is: If I look at period 1880-2005, and divide it to two parts: 1880-1950 and 1950-2005. About 90% of fossil fuel burning occurred on later part. Seal level and CO2 in atmosphere increased "roughly" linearly in both parts. Even it seems very likely that we are increasing atmospheric CO2 by burning fossil fuels, it is hard to believe that this is the whole truth. On the other hand atmospheric CO2 remained constant for long time before 1800, and it seems unlikely coincidence that exploding human population would have nothing to do with it. Could cutting down forests for agriculture have anything to do with it? Best regards, Pekka
  48. Comparing CO2 emissions to CO2 levels
    Tony The CDIAC site (Fig. 1 caption) reports these data as "fossil fuel" carbon, so I presume it does not include deforestation/biofuel burning. They give lots of references on sources and estimation techniques; not a literature with which I'm familiar. The slope by the end of the curve is pretty dramatic. No sign of any effective political/societal will yet.
  49. Comparing CO2 emissions to CO2 levels
    Thanks for that article, Chris! The Discussion section is an especially good summary to counter the argument that "CO2 stays in the atmosphere only for five years."
  50. Philippe Chantreau at 03:37 AM on 15 October 2009
    How we know global warming is still happening
    Shawnhet, you won't see more cloud formation if the temperature/dew-point spread is unchanged, as will likely be the case if relative humidity is conserved. If relative humidity decreases, you'll see less cloud formation, regardless of the absolute humidity. And you seem to assume that, as warmer air (i.e. containing a higher absolute humidity) will reach the dew point, all of its moisture content will condense and precipitate. I seriously doubt that it is that simple. This hypothesis (which you do not substantiate with science papers) is also very much in contradiction with references you provided on vegetal NPP, especially what has been observed over the Amazon basin: more sun exposure, due to lower cloud cover. Choose which hypothesis you want to defend, but keep in mind that the Amazon drying is based on empirical obervations.

Prev  2564  2565  2566  2567  2568  2569  2570  2571  2572  2573  2574  2575  2576  2577  2578  2579  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2026 John Cook
Home | Translations | About Us | Privacy | Contact Us