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  2205  2206  2207  2208  2209  2210  2211  2212  2213  2214  2215  2216  2217  2218  2219  2220  Next

Comments 110601 to 110650:

  1. A detailed look at Hansen's 1988 projections
    Scrooge, natural cooling is ignored in GCM. It happens on a time frame of millennia which usually is not considered.
  2. A detailed look at Hansen's 1988 projections
    Ken Lambert, still confusing forcings and feebacks, do you? Anyway, Hansen calculation also are "the result of ALL the forcings - both radiative and feedbacks." (sic). And within 5%.
  3. A detailed look at Hansen's 1988 projections
    First I want to say that to be able to come up with those projections in 1988 is remarkable. I think I was still using an Atari 800 at the time. Now this may be a stupid question but as discussed in a previous post, is the idea that we should be naturally cooling incorporated into the model. Of course I assume it is but just one of those nagging questions.
  4. A detailed look at Hansen's 1988 projections
    Riccardo #16 Unfortunately the measures 'air surface temperature' and GISS and HADCRUT3 temperature anomalies are the result of ALL the forcings - both radiative and feedbacks. Claiming that Hansen was out by only 5% on half the story when the feedbacks (particularly WV and CO2 interaction) are the least understood is the missing part of this article. So we are closest Scenario C with the temperature record??
  5. It's the sun
    I say the Sun is the dominant factor in climate change. If you read the new work by Frederick Bailey, on the soon to launched web site www.solarchords.com and his books, you will see the background to two discoveries, one is, what drives sunspot production, the pattern has been discovered and this led to a much greater discovery i.e. It has been cleary shown that the generally accepted value of 1AU for the Earth - Sun distance around the ecliptic plane has been found to be wrong. This work clearly shows that sunspots per se do not influence climate change but because the way they are produced, they are indicators that the AU value is changing and it is this that affects the climate. Because the two events are closely linked in time, people thought that sun spots cause climate change, they do not. This also led on to investigate why does not the TSI measurements reflect the findings made. This site clearly states here; http://www.skepticalscience.com/acrim-pmod-sun-getting-hotter.htm "There is no single continuous satellite measurement of Total Solar Irradiance" In researching the this and other sites I soon realised why the TSI variation that should be seen has not been identified, because only the variation in the output of the Sun is being measured, not the total output or TSI. The variation is then appliked to the standard figure of 1368w per Sq M and allowing for the expected orbital position. Bailey's work clearly shows the reason for the historical hot and cold periods etc.
  6. Should The Earth Be Cooling?
    Yooper #58, #61 The critical measurement is the TOA imbalance which nets all the heating and cooling forcings. Ref Fig 2.4 of AR4 which gives a total net anthropogenic forcing of +1.6W/sq.m. To this number is then added the climate responses which mainly consist of radiative cooling (from a raised Earth temperature of 0.75 degC as per S-B) of about -2.8W/sq.m and WV and Ice Albedo Feedback of about +2.1 W/sq.m. (Ref Dr Trenberth Fig 4 'Tracking the Earth's global energy) The sum is then +1.6 -2.8 +2.1 = +0.9W/sq.m All the heating and cooling forcings are acting in concert. S-B is emitting IR, Aerosols and clouds are reflecting incoming Solar heat, while CO2GHG are supposedly trapping Solar heat at lower levels (the mechanism is more correctly slowing down the transfer rather than 'trapping' heat) which tends to raise the equilibrium temperature as the analogy of a better insulator increases the T1-T2 temperature difference for a given heat flux transferred. What is certain is that CO2GHG forcing (currently claimed at about 1.6W/sq.m) is logarithmic with CO2 concentration, and S-B radiative cooling is exponential (proportional to T^4). Where these forcings and the others cross is where the forcing imbalance is zeroed and the new equilibrium temperature approached. The CO2GHG theory hangs on the interaction of WV and CO2 in the atmosphere and what will be the surface temperature rise for a unit rise in the IR emitting temperature of the Earth as seen from space. For the first law to be satisfied, most of heat flux 'imbalance' of 0.9W/sq.m should show up in the oceans due to the tiny relative storage capacity of the land and atmosphere (about 5%). OHC is proving most elusive to measure but Argo is the best we have at the present and the latest Willis analysis is not finding the 'missing heat' below 1000m. Here is the story on sea level rise: Thanks to HumanityRules nice summary: quote; "I've found 4 papers looking at closing the sea-level budget around 2003-2007. The latest is from this year. Basin patterns of global sea level changes for 2004–2007 You-Soon Chang, Anthony J. Rosati, Gabriel A. Vecchi Journal of Marine Systems 80 (2010) 115–124 Chang, like the others, calculate the steric and mass components using ARGO and GRACE and compare it to the total change calculated from altimetry. They handily summarize the 4 published attempts to close the sea-level budget in a table. Chang et al (2010) STERIC −0.11±0.22 MASS 0.70±0.34 TOT 2.67±0.52 Willis et al. (2008) STERIC −0.5±0.5 MASS 0.8±0.8 TOT 3.6±0.8 Leuliette and Miller (2009) STERIC 0.8±0.8 MASS 0.8±0.5 TOT 2.4±1.1(2.7±1.5) Cazenave et al. (2009) STERIC 0.37±0.1 MASS 1.9±0.1 TOT 2.5±0.4 Chang and Willis fail to close the budget and interestingly fail with pretty much the same numbers. Leuliette and Cazenave manage to close the budget but by very different means. Leuliette through an equal contribution from steric and mass. Cazenave primarily (80%) through mass." Note Leuliette is the only one of the 4 analyses to get equal mass and steric. Error bars are very wide on all analyses. More mass means less OHC content increase and most coming from ice melt which sinks very ittle heat compared with the claimed imbalance. Yooper - when you have supped on this - please refrain from belching on about my 'misunderstandings', Happy to debate you on any or all of the above.
  7. A detailed look at Hansen's 1988 projections
    Ken Lambert, it's way too easy to talk about apologia without even bothering to look at the details on how things work. This attitude just highlight the unwillingness to learn the science but still dismissing it. The feedbacks are, indeed, feedback, not forcings. Why should they be listed in the same table as the forcings? The albedo, water vapour feedbacks and others are the results of the full calculations and are not parametrized.
  8. The contradictory nature of global warming skepticism
    Baz, I dug around in the archives for a good writeup I remembered on statistical significance in the temperature data set. If you read the linked article you may better understand why these 'short term trends' you are relying on are not considered statistically valid trends at all. Ironically, you are dismissing a warming trend since 1995 which has greater than 90% confidence in favor of a 'flat' trend since 2001 which has much lower statistical significance.
  9. A detailed look at Hansen's 1988 projections
    Sense Seeker, #10 in this post there's a comparison of Hansen's calculation in 1988 not a thorough comparison of model results. How could he know the actual emissions in the future? Someone else could do now some new calculations with actual emissions and best available model now, but this is a different story. A good idea for a new post ;) #13 the model is not on radiative forcing alone, it's much more than this; it is called a General Circulation Model (GCM). Radiative forcings come from radiative tranfer codes that are pluged into the GCMs. I think you should dig a little bit more on GCMs; NASA GISS provide a lot of informations (and the code itself) that I'm sure you'll find intersting.
  10. The contradictory nature of global warming skepticism
    Baz #296: "Okay, there seems to be some mis-reading here again. Rob, first of all, 0.12 c per decade is NOT statistically significant - ask CBD if you don't believe me." Ask me? Ok. You appear not to know what "statistically significant" MEANS. It has nothing to do with the degree of warming, only the confidence that this warming represents a statistically valid trend rather than merely being an artifact of random fluctuations. A warming trend of 0.12 C per decade could be either statistically significant (the usual confidence level is 95%) or not depending on the data from which it is derived.
  11. A detailed look at Hansen's 1988 projections
    I clicked the link to NASA-GISS for the +1.1W/sq.m 2010 relative to 1984 forcing here: http://data.giss.nasa.gov/modelforce/RadF.txt and found data only to 2003 and nothing like +1.1. Please explain the calculation? My eyesight must be playing tricks for I see the actual temperatures running close or below Scenario C not Scenario B. Is that what you meant? And what of the climate responses - where is the estimate of WV and Ice albedo feedback and radiative cooling feedback? Seems like a contrived Hansen apologia with only half the story to me.
  12. The contradictory nature of global warming skepticism
    Spot the differences : Baz : "Please retract the "liar", and I've never said I am irrational." Baz : "Archiesteel - I never claimed to be rational!" So, if you don't claim to be rational and have never said you're irrational, what do you claim to be ? Baz : "You say, "You seem to be arguing that if AGW theory is correct then the temperature would have to increase at a near constant rate." No, I've never said that, not once." Baz : "With no volcanoes the global temp should be ramping up and away." Baz : "How so - against ever-increasing emissions of CO2 and methane? Why isn't the temperature rising Guy?" Baz "Because when warming didn't continue at the same pace (around 2005) I began to question if I was right about my beliefe in warming." So, temperatures should be "ramping up and away", "rising", continuing "at the same pace" but that doesn't mean the same as "at a near constant rate" ? I think you are getting more confused with every post and that is highlighted by this quote from your penultimate post above : "...0.12 c per decade is NOT statistically significant..." What does that mean ?
  13. The contradictory nature of global warming skepticism
    Re: Baz (296, 297)
    "CBD, Try getting your facts right if you're going to accuse others. I didn't "carefully cherry-pick" that period, it was done by Phil Jones here http://news.bbc.co.uk/1/hi/8511670.stm Happy?"
     Ok, you got my interest with your use of "cherry-pick". Let's actually look at what your cite says, shall we?
    "C - Do you agree that from January 2002 to the present there has been statistically significant global cooling? No. This period is even shorter than 1995-2009. The trend this time is negative (-0.12C per decade), but this trend is not statistically significant."
    The time period in question, 2002 to present, was actually brought into play by the commentator, BBC's environment analyst Roger Harrabin (who put questions to Professor Jones, including several gathered from climate skeptics). So you're wrong on that part. I also see that Professor Jones said the period in question was "not statistically significant". Wrong again, sir. You seem to have a severe mental block about statistical significance and trends (it must be that cherry-flavored icing on all the graphs). Dude, you seriously have to get over your trying to force the data to say what it simply doesn't say. The evidence shows you're wrong, the science shows your wrong and your own source you cite to support you shows you're wrong. If you think you're right and everyone else (including experts with lifetimes of experience in the field) say you're wrong, maybe it's because you are wrong... The Yooper
  14. The contradictory nature of global warming skepticism
    quoting Phil Jones:
    "I also calculated the trend for the period 1995 to 2009. This trend (0.12C per decade) is positive, but not significant at the 95% significance level. The positive trend is quite close to the significance level. Achieving statistical significance in scientific terms is much more likely for longer periods, and much less likely for shorter periods. "
    Baz You are confusing the statistical usage of 'significance' with its everyday use. He is not saying 0.12c/decade is unimportant, he is saying that he can only say it is 0.12C with slightly less than 95% confidence.
  15. The contradictory nature of global warming skepticism
    http://woodfortrees.org/plot/hadcrut3vgl/from:2000/plot/hadcrut3vgl/from:2000/trend http://woodfortrees.org/plot/hadcrut3vgl/from:2001/plot/hadcrut3vgl/from:2001/trend http://woodfortrees.org/plot/hadcrut3vgl/from:2002/plot/hadcrut3vgl/from:2002/trend Flat
  16. The contradictory nature of global warming skepticism
    Okay, there seems to be some mis-reading here again. Rob, first of all, 0.12 c per decade is NOT statistically significant - ask CBD if you don't believe me. As for flat, well that would be here then: http://woodfortrees.org/plot/hadcrut3vgl/from:2001/plot/hadcrut3vgl/from:2001/trend Now, you can always shoose different years and time frames if you want to! It's not exclusive. Whether it's VERY slightly up, or VERY slighty down, it's flat! CBD, Try getting your facts right if you're going to accuse others. I didn't "carefully cherry-pick" that period, it was done by Phil Jones here http://news.bbc.co.uk/1/hi/8511670.stm Happy? Re volcanoes, you know perefctly well I was talking about cooling volcanoes (the Iceland puff never did anything) as it was written clearly in 289, not any little puff (which are always happening somewhere in the world). Talk Pinotubo. As for comments, you must also see that I have taken great pains to answer genuine questions actually posed. If I missed one of your posts then it was as I was replying to others at the time. I'll leave others to judge that. You say, "You seem to be arguing that if AGW theory is correct then the temperature would have to increase at a near constant rate." No, I've never said that, not once. archiesteel: Flat? http://woodfortrees.org/plot/hadcrut3vgl/from:2001/plot/hadcrut3vgl/from:2001/trend Please retract the "liar", and I've never said I am irrational. Read back and check what I actually said on that. Re 'Where's the heat?' So 3 years is good enough for you? I say again, the last 10 years of HadCRUt is flat.
  17. A detailed look at Hansen's 1988 projections
    There is one more thing I don't understand. The calculations did not use Hansen's model, but a set of equations from a different source (Myhre et al 1998). Comparison with the forcings as established (beyond doubt, is seems) with an unexplained NASA method, and then conclude that Hansen's model was almost accurate... I am sorry, I can see Hansen got it about right, but this posting adds little to my understanding.
  18. A detailed look at Hansen's 1988 projections
    And if you want to test Hansen's scenario B as a prediction, rather than the underlying model, you needn't bother with any calculation. You can just read if from the graph.
  19. A detailed look at Hansen's 1988 projections
    Once the data for 2010 are used, his accuracy will have been prophetic.
  20. A detailed look at Hansen's 1988 projections
    Ricardo, you are mostly right but not completely. (Unless I missed something more, which is of course now a non-negligible option.) Shouldn't Table 1 give the realised Greenhouse Gas (GHG) Concentration in 1984 and 2010, rather than the one from Scenario B? The calculations seem to be based on scenario B, not the realised emissions. The real ones may be most like scenario B compared to A or C, but are unlikely to be identical. If you only want to test the model, you need to use the observed emissions as input.
  21. A detailed look at Hansen's 1988 projections
    Sense Seeker, you missed something. Two quotes from the post: "Scenario A assumed continued exponential greenhouse gas growth, which did not occur." "Hansen's Scenario B has been the closest to the actual greenhouse gas emissions changes."
  22. A detailed look at Hansen's 1988 projections
    Something here does not make sense. Nowhere do you mention what the actual emissions WERE over the intervening period. You cannot simply compare one of Hansen's scenarios with what actually happened in terms of outcomes, if you do not take into account the inputs. If the temperature curve nicely follows Hansen's scenario B, but the emissions increased exponentially (i.e., according to scenario A), Hansen's model was overestimating by a much larger margin.
  23. How we know the sun isn't causing global warming
    Dana1981, I still don't think your section on the D-O events is particularly convincing, especially with regards to the so called "timing flaw" you mention. For the sake of argument, if the LIA was the last cold phase of the D-O cycles, we could place the MWP as the peak of the last warm-phase, and subsequently the Earth should be warming now. Remember, the 1470 figure is the periodicity -- the time interval between peaks (or troughs). The Earth was in a trough several hundred years ago, and it should now be heading towards a peak (i.e. warming). So the fact that the LIA may have been the most recent cold phase of the D-O cycles does not preclude them from adding to the recent warming; quite the opposite. Please see my previous post on this thread for my reasoning on why D-O events cannot have had anything more than a negligible affect on global temps over the past few centuries.
  24. Philippe Chantreau at 18:05 PM on 20 September 2010
    Jupiter is warming
    And Bob, let's not forget that Venus is warmer than Mercury, which is closer to the Sun...
  25. Philippe Chantreau at 17:58 PM on 20 September 2010
    It's cosmic rays
    Continued from the thread mentioned above: HR, the word would be laughable but, really, what is there to hang on in the Duplissy paper itself? What paper since Duplissy has been published using CLOUD data? References? Anything yielding more conclusive results? The point was not to reveal problems in the experimental design, but the problems were uncovered nevertheless. If those ultra clean walls can release vapors susceptible of corrupting the results, I don't even want to begin imagine what happens in the real atmosphere, where CCN are already present by the hundreds per cubic cm.
  26. Philippe Chantreau at 17:41 PM on 20 September 2010
    A South American hockey stick
    HR, the word would be laughable but, really, what is there to hang on? What paper since Duplissy has been published using CLOUD data? Do you have something of any substance? The point was not to reveal problems in the epxerimental design, but the problems were uncovered nevertheless.
  27. 2nd law of thermodynamics contradicts greenhouse theory
    KnuckleDragger, to explicitly address your first question on absorption/reflection, thinking in this terms could be confusing. In everyday life we call reflection the "bouncing back" of light from a solid or liquid surface. In a gas there's no surface and it could be hard to understand how "reflection" may occur. I think it's easier to think in terms radiation absorption/emission. Quoting from the post: "Any substance that absorbs thermal radiation will also emit thermal radiation; [...]. The atmosphere absorbs thermal radiation because of the trace greenhouse gases, and also emits thermal radiation, in all directions." The backward emitted radiation is what you (and others) call reflection. So, the answer to your question is that CO2 at high concentration is a good absorber and reflector.
  28. Global warming and the unstoppable 1500 year cycle
    Here is a question to the skeptics: why don’t you provide a classification of the different climate theories held by climate skeptics ? People who don’t believe in global warming have entirely different convictions from those who do believe the earth is warming due to natural causes. In fact, these 2 points of view are as different as any skeptic theory is from the AGW theory. In order to advance the discussion, the classification “climate skeptic” is just not enough. F.i. the alternative theories could be named: NoGW, NatGW (with subclassifications: NatGW_solar, NatGW_ocean_currents, …), NonCatAGW (non-catastrophical AGW), etc. AGW is just one of the many possible climate theories – with an overwhelming amount of evidence on its side …
  29. A detailed look at Hansen's 1988 projections
    One thing that folks should keep in mind is that your typical el-cheapo Best-Buy/Walmart/whatever laptop has more computing horsepower than what Hansen had available to him to conduct his climate-modeling simulations back in 1988. This should put things in perspective here, and also give folks a fuller appreciation of Hansen's genius.
  30. Global warming and the unstoppable 1500 year cycle
    (#12)My impression actually is that most skeptics claim we are cooling, and have just entered a cooling phase that will go on for decades. Skeptics not only believe that the Earth is cooling; they also believe that the Earth is warming. They believe that the warming can be attributed to natural causes, and they believe that the warming is due to the urban heat-island effect. In addition, they believe that it's impossible to tell whether the Earth is warming or cooling because so many temperature stations are set up next to air-conditioners and bbq grills. They believe all of these things; that's how they make sure that they have all of their bases covered.
  31. A detailed look at Hansen's 1988 projections
    @paulm: That website proves nothing. Radiative forcing F is a multivariate nonlinear function. But for small variations, we can Taylor-expand and to first order it is the sum of the first derivatives. The particular objection raised is that for example d^2F/d(CO2)/d(N2O) is not zero. I agree it's not. But its contribution to dF is much smaller than the linear part. As it's unknown, it contributes to the uncertainty (error-bar) in the calculation.
  32. A detailed look at Hansen's 1988 projections
    The other thing that I think should be pointed out is that Hansen scenario B was also taking into consideration a large volcanic eruption in 1995 while Pinatubo - which can be clearly seen in the actual data - was in 1991 - once you also correct for that the scenario B already looks identical to real measured values!
  33. Why positive feedback doesn't necessarily lead to runaway warming
    Further search of previous research of the temperature limiting factors of biosphere... From http://www.dbio.uevora.pt/Micro/Brock.pdf ("Life at high temperatures", review on prior research, unfortunately it doesn't include much on terrestrial vascular plants.) "We found visible algal growth (of the unicellular blue-green Synechococcuts) at temperatures up to 73° to 75°C, but not at higher temperatures (24)" and "Quantitative studies of the algal mats along thermal gradients in hot springs have shown a definite correlation between the temperature and the algal biomass (33). In the Yellowstone hot springs, maximum algal biomass was found at albout 55°C, and it falls off sharply as the temperature increases above 55°C (34)." So one limit of inhibition for high (too hot for humans) temperatures is 55°C and photosynthesis ends at 75°C. Above this temperature all photosynthecic life will decompose and photosynthesis needs to be born or moved to the area again. Geological processes will eventually bury the decomposed carbon. further: "Thus, it is surprising that eucaryotic algae are not common at temperatures above 40°C, whereas eucaryotic fungi are found up to 60°C (14)." So 40°C is about the maximum limit when oceans will turn into carbon emitters. lastly: a point on scientific inertia... "Most of the surface of the earth has a moderate temperature, with an average of 12°C (15)." checking this up, it turns out this was an approved value in 1955: "15. H. F. Blum, Time's Arrow and Evolution (Princeton Univ. Press, Princeton, N.J., 1955)."
  34. A detailed look at Hansen's 1988 projections
    I wonder if you would consider typesetting the math with LaTeX? Would make it lots more readable. You could e.g. use http://www.codecogs.com/latex/eqneditor.php. Or if you already know LaTeX, just use TTH: http://hutchinson.belmont.ma.us/tth/
  35. A detailed look at Hansen's 1988 projections
    Heres some interesting analysis... http://residualanalysis.blogspot.com/2010/02/twin-ghgs-paradox.html The Twin GHGs Paradox The means by which a greenhouse gas (GHG) forces climate change is sometimes called radiative forcing.
    Moderator Response: Please provide more context when you post a link.
  36. actually thoughtful at 14:30 PM on 20 September 2010
    A detailed look at Hansen's 1988 projections
    It is hard to look at Hansen's 1988 work without seeing he got it right! A few quibbles, but the major mechanisms are all included, and he is off by a few tenths of a degree over 22 years! And the fix is very clear - he used 4.2 instead of 3 or 3.4 for climate sensitivity. The takehome message is climate scientists have this dialed in. With 22 years more research, current models are that much better. "Hansen got it wrong" is a lie - pure and simple.
  37. A detailed look at Hansen's 1988 projections
    Misprint on the first line. Says 1998; should be 1988.
    Response: Fixed, thanks
  38. Climate sensitivity is low
    Re: Timothy Chase (51) Thanks for taking the time to put together such a thorough comment. It's appreciated. The Yooper
  39. A South American hockey stick
    @HR: quoting Judith Curry doesn't automatically equate providing scientific evidence that supports your arbitrary claims. I'm still waiting to have some valid sources cited to support your claim that 1/3 to half the warming is anthropogenic. Otherwise, we'll have to assume you pulled these figures out of the place where TSI is nil.
  40. A South American hockey stick
    Re: HumanityRules (47) You should have a read of this. And ponder on it. The Yooper
  41. 2nd law of thermodynamics contradicts greenhouse theory
    Re: KnuckleDragger (11) I'm glad you're inquisitive and I'm glad you're here.
    "It seemed to me, that the 2nd law put the final nail in the coffin of this (CO2) debate. Yet, it's still alive. How is it possible ?"
     This is a common objection from people who do not understand the greenhouse effect (or the 2nd law of thermodynamics, for that matter). A simple understanding of the greenhouse effect:
    Longwave radiation from the earth’s surface is absorbed by many trace gases, including water vapor and CO2. The absorption causes these gases to heat up and energy is radiated back out – both up and down. The upward radiation is effectively “no change”. The downward radiation adds to the energy received from the sun and heats up the surface of the earth more than if this downward radiation did not occur.
    The 2nd "law", simply put:
    "Heat generally cannot flow spontaneously from a material at lower temperature to a material at higher temperature"
    What this means is this:
    No net energy can flow from a cold body to a hot body. In the case of the real “greenhouse” effect and the real 2nd law of thermodynamics, net energy is flowing from the earth to the atmosphere. But this doesn’t mean no energy can flow from the colder atmosphere to the warmer ground."
    It simply means more energy flows from the warmer surface to the colder atmosphere than in the reverse direction. Sources: Here and here.
    "The theory that man made CO2 is the cause of Global Warming has had so meny holes punched through it - I don't understand how it's survived this long...What is it that I'am not understanding?"
    The first part of your statement is wrong on every level, but I can understand the confusion you must feel. If it's so wrong, why does every scientific body in the world support it? Why does Shell Oil, of all things, support it? KnuckleDragger, I'm a simple man too. If someone is telling you that CO2 doesn't warm the Earth or that it's the sun or that it's cooling, or it's a natural cycle, then you have 2 possible answers:
    1. They don't understand quite a bit about science, physics, the greenhouse effect or pay attention to developments in the natural world... OR... 2. They're lying to you...
    The greenhouse effect is quite well understood. Here's a quick backgrounder on the GHE, CO2 and AGW (the important bit is the response to Question 1 & the 8 steps outlined). Basically, it come down to this: No-one has been able to come up with a physics-based alternative to the observed & predicted effects of CO2 and GHG's that explains what we can see and measure that ALSO explains why CO2 derived from fossil fuels DOESN'T act as a GHG. At this point, being an inquisitive man, you probably will have more questions. Feel free to ask; the kind people here will be glad to help you gain an objective understanding. The Yooper
  42. A South American hockey stick
    HR, Unfortunately, Judith Curry cites no sources for her probability "weighting". She does, however, assert that the colors of the Italian flag can help us figure it all out.
  43. A South American hockey stick
    43.Philippe Chantreau I actually linked to the video because he spends most of the time presenting data (including paleo) suggesting there is a fair degree of natural variability in the pre-industrial record. As he says he's not presenting answers just raising questions. The intent was to use it to highlight the wider discussion around natural variability not specifically GCR's Maybe you know that Duplissy et al (2010) was the 2009 data from a pilot run. The whole point was to bring to light errors in experimental design. I have no sense of the difficulty involved in these highly complicated physics experiments but I expect its high. Nobody really holds any value to this data, it's more like an update on how this multi-million dollar project is going. As well as Svenmark there are a total of 19 collarborating groups, from 19 separate institutes working on this project. It's laudable that you should suggest that this work is being subverted by deniers. 42.RickG Judith Curry suggests the IPCC has a very low estimate of uncertainty which leads them to the conclusion that late 20th C warming is 5% assigned to uncommitted belief, 67% assigned to anthropogenic forcing, 28% assigned to natural variability. Her own assessment of uncertainty leads her to believe 40% assigned to uncommitted belief, 30% assigned to anthropogenic forcing, 30% assigned to natural variability. This means anthro could be anywhere between 30-70%, but natural could also be 30-70%. I based my own opinion on papers looking at regional natural variability and email exchanges with their authors. But I also hold the opinion that the IPCCs drive to reduce uncertainty is not based on science but on political necessity.
  44. 2nd law of thermodynamics contradicts greenhouse theory
    So is CO2 a good reflector while a poor absorber or is it a good absorber but a poor reflector ? It seemed to me, that the 2nd law put the final nail in the coffin of this (CO2) debate. Yet, it's still alive. How is it possible ? The theory that man made CO2 is the cause of Global Warming has had so meny holes punched through it - I don't understand how it's survived this long. It's been de-bunked by simple sciance on so meny levels, it should have been dead long ago. All the while, people far smarter than myself keep pushing it along. What is it that I'am not understanding? I'm a simple man, thats probably a bit more inquisitive than most, looking for answers. Which is what lead me here.
    Moderator Response: Please don't post the same comment repeatedly. I deleted your second one.
  45. Global warming and the unstoppable 1500 year cycle
    The problem for Thingadonta’s arguments is that global warming is occurring as evidenced by its effects in both the Arctic and Antarctic. In the north there is empirical evidence of depletion of sea ice and melting of the Greenland ice cap. In the south there is melting of the West Antarctic ice sheet and retreat of glaciers, while in East Antarctica there is evidence of increasing ice loss at the fringes of the ice cap. Grace satellite measurements confirm that these changes are occurring and doing so at an increasing rate. Thingadonta seems to assert that since ice ages are a global phenomena, this disproves that CO2 induced global warming is now occurring. Frankly, I don’t understand that argument. The present problem with CO2 is that human activity is responsible for it increasing at rates vastly in excess of that which would otherwise occur. In decades we release into the atmosphere what would otherwise take hundreds of millennia to accumulate. Can that occur without causing the global warming which is now so clearly evident?
  46. Global warming and the unstoppable 1500 year cycle
    "Although there are a lot of people who deny the warming, my understanding is that most skeptics believe there is a natural warming." My impression actually is that most skeptics claim we are cooling, and have just entered a cooling phase that will go on for decades. "It's cooling" is #4 on the skepticalscience most used skeptic arguments and I think that's probably about right. What I see when I trawl google news for comments sections of climate related news articles is a lot of people throwing out the claim that the Earth has stopped warming and is now cooling. They cite Phil Jone's statement about 1995-, they cite a recent switch into a negative PDO. They cite certain russian scientists who predict the maunder minimum stuff.
  47. Global warming and the unstoppable 1500 year cycle
    Answering #4, Daved Green- The problem here is not so much that being basic, it lacks detail, but rather, that the logical flow of the article is jerky and scattered, and the wording fatally imprecise. Under such circumstances, since, as #3 points out, "'Skeptics' use bits of science like flack to deflect focus from their core arguments", they latch on to each one of these shortcomings and do exactly that -- with gusto and great effect. As an example of the jerky flow, consider even the very first sentence. It announces that there are two things 'interesting'. Then it immediately lists them. But frankly, from that list, neither one sounds 'interesting'. So already the logical flow most plausibly promised by the opening sentence has been lost. But then the article switches to the 1500 year cycle itself. This switch is quite abrupt, since we STILL haven't seen anything 'interesting' in the "two things interesting". But here too, we fail to keep the logical flow: for the unfortunate phrase "global temperature see-saw effect" spoils the whole paragraph. How so? Because the phrase "global temperature" would most logically mean a -single- temperature, which in turn would most likely be an -average- temperature. But the 'see-saw' described must be rising temperature in one hemisphere, while the temperature falls in the other (and vice versa). At best, this would be an example of the rhetorical effect known as 'paraproskokian', since the expected meaning of the word turns out not to be ther right one. But as Wikipedia points out, paraprosdokiam "is frequently used for humorous or dramatic effect, sometimes producing an anticlimax" -- none of which fits here. (See http://en.wikipedia.org/wiki/Paraprosdokian). Frankly, if I wasn't already convinced of the basic truth of the AGW hypothesis, this article would not have convinced me either. It would not even have convinced me to research it further -- especially since it contains no references for its highly contentious claims. BTW: that final contentious conclusion is another example of fatal imprecision in wording: what is being "recorded all around the world" is NOT "the current temperature increase caused by CO2". What is being recorded is merely "the current temperature increase". How much of it is caused by CO2 is exactly the bone of contention (assuming that no one still doubts the accuracy of the measurement -- although you know that because of 'Climategate' they do doubt it). You only give skeptics excuses for disbelief when you misstate it that badly. Unsupported statements of the central thesis (here that CO2-caused temperature rise is already being recorded) belong in the proem, the statement or perhaps on the conclusion, but ONLY when the support has been provided in (the body of) the argument. But where IS it? It just isn't there. Without it, you have no rebuttal at all.
  48. Climate sensitivity is low
    Dana, over at Climate Progress you wrote:
    I should mention, the 'Climate sensitivity' is not specific to CO2′ section isn't quite correct because different forcings have different efficacies. I updated the advanced version of this rebuttal to clarify this point. Here's the link if you want to do the same: http://www.skepticalscience.com/climate-sensitivity-advanced.htm
    I was trying to respond to that, but too many links has put my post in the could-be-spam queue, so I thought I might post this here as well in the hope that some might find it helpful. Definition of Radiative Forcing:
    The definition of RF from the TAR and earlier IPCC assessment reports is retained. Ramaswamy et al. (2001) define it as 'the change in net (down minus up) irradiance (solar plus longwave; in W m^–2) at the tropopause after allowing for stratospheric temperatures to readjust to radiative equilibrium, but with surface and tropospheric temperatures and state held fixed at the unperturbed values'. 2.2 Concept of Radiative Forcing http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-2.html
    The idea here is that increased solar radiance or increases in CO2 concentration affect the balance of radiation entering/leaving the climate system -- and will result in a response at the "top of the atmosphere" or - tos - which is typically taken to be at the tropopause which separates the troposphere and the stratosphere. Feedbacks are in response to this change. Definition of Climate Sensitivity:
    The long-term change in surface air temperature following a doubling of carbon dioxide (referred to as the climate sensitivity) is generally used as a benchmark to compare models. Climate Change 1992 The Supplementary Report to the IPCC Scientific Assessment, pg. 16 http://www.ipcc.ch/ipccreports/far/IPCC_Suppl_Report_1992_wg_I/ipcc_far_wg_I_suppl_material_full_report.pdf
    The above definition of climate sensitivity is however for the Charney Climate Sensitivity that takes into account the fast feedbacks, e.g., water vapor, clouds, sea ice, etc., but omits the slow feedbacks associated with changes in vegitation, feedbacks due to the carbon cycle and ice sheets -- the latter of which are land-based. Definition of Efficacy:
    Efficacy (E) is defined as the ratio of the climate sensitivity parameter for a given forcing agent (λi) to the climate sensitivity parameter for CO2 changes, that is, Ei = λi / λCO2 (Joshi et al., 2003; Hansen and Nazarenko, 2004). Efficacy can then be used to define an effective RF (= Ei RFi) (Joshi et al., 2003; Hansen et al., 2005). For the effective RF, the climate sensitivity parameter is independent of the mechanism, so comparing this forcing is equivalent to comparing the equilibrium global mean surface temperature change. 2.8.5 Efficacy and Effective Radiative Forcing http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-8-5.html
    Why Efficacies of Different Forcings are Different:
    The efficacy primarily depends on the spatial structure of the forcings and the way they project onto the various different feedback mechanisms (Boer and Yu, 2003b). Therefore, different patterns of RF and any nonlinearities in the forcing response relationship affects the efficacy (Boer and Yu, 2003b; Joshi et al., 2003; Hansen et al., 2005; Stuber et al., 2005; Sokolov, 2006). Many of the studies presented in Figure 2.19 find that both the geographical and vertical distribution of the forcing can have the most significant effect on efficacy (in particular see Boer and Yu, 2003b; Joshi et al., 2003; Stuber et al., 2005; Sokolov, 2006)... 2.8.5.1 Generic Understanding http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-8-5-1.html
    For more on radiative forcing and related concepts please see: Chapter 2: Changes in Atmospheric Constituents and in Radiative Forcing http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2.html Note: calculations performed by climate models do not involve the concepts of forcing, climate sensitivity or efficacy. The calculations of climate models are themselves based up the physics. Analysis in terms of forcings, climate sensitivity and efficacy only come afterward -- as a means of conceptualizing the results for the ease of our understanding.
  49. Should The Earth Be Cooling?
    No worry's Daniel-- I also make the same mistake from time-to-time. My comment/clarification was mostly directed at "skeptics".
  50. Should The Earth Be Cooling?
    Re: Albatross (60) Thanks for the reminder. :) I was a little fired up & used KL's quote back in the context he meant it (the non-science, or layman's everyday usage). I should probably have corrected that misunderstanding as well. But it's difficult to catch everything in a comment like that because of the sheer amount of misunderstandings going on. I will try to exercise more judiciousness in my words. BTW, the NAS definition you cite is very similar to the NAS statement in May on global warming:
    " A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems…. Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities."
     Source here. Thanks again, The Yooper

Prev  2205  2206  2207  2208  2209  2210  2211  2212  2213  2214  2215  2216  2217  2218  2219  2220  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2025 John Cook
Home | Translations | About Us | Privacy | Contact Us