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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.

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Comments 102001 to 102050:

  1. A Cloudy Outlook for Low Climate Sensitivity
    @Eric (skeptic): you are exaggerating the impact of TSI and galactic cosmic rays. Also, what do you mean by "obviously nature is damping man's additional CO2"? The problem with your theory is that it is not confirmed by oservation. There is no indication that external factors such as TSI or GCR could overcome AGW. Until you have actual evidence supporting your theory, we'll have to continue assuming it is very unlikely.
  2. A Cloudy Outlook for Low Climate Sensitivity
    @Camburn: "The temperature trend for the past 15 years has been flat." No, it isn't. Please acknowledge you are wrong about this. Thanks.
  3. The human fingerprint in the seasons
    @RSVP: why don't you tell me right away where you're trying to go with this, so we save some tiem? The resl question is, why not take the middle value, i.e. 17.5%? That gives us 1.365C. So, what about it? You seem to be missing the point I already demonstrated how your "equation" was wrong. The fact you avoided responding to my counter-arguments is all we really need to know. Thanks for playing.
  4. Eric (skeptic) at 08:28 AM on 6 December 2010
    A Cloudy Outlook for Low Climate Sensitivity
    #25 archiesteel "....with a possible increase over [CO2 warming] due to increased solar activity." and #26 muoncounter "We can all play 'what if' ... if you like." Thank you for your responses. The sensitivity to CO2 warming is by definition a 'what if' game because sensitivity is modulated by external factors (solar and celestial) which are not predictable, they can go either way. A paleo-based calculation of sensitivity has to consider variations in external factors, solar or not (e.g. GCR) which are not adequately represented in the paleo record. When GCRs increase or decrease due to some celestial cause (modulated by the sun), both the paleo temperatures decrease or increase in response and CO2 follows. We see that happen in centuries or longer (not to mention that's all the resolution that we have in ice core and other proxies). So CO2 feedback is a minor and slow feedback factor; paleo or present day (obviously nature is damping man's additional CO2, not amplifying it). Thus the CAGW hypothesis depends on water vapor amplification of CO2 warming. Talking about methane is likewise not convincing since it will take centuries for enough permafrost to melt to get methane feedback. Water vapor is partly covered in the cloud discussion above and partly not. The non-cloud portion of the water vapor feedback depends on the distribution of water vapor (the evenness) which in turn is somewhat dependent on clouds, but also winds, precipitation, soil moisture, etc. The claim that the major uncertainty in sensitivity can be adequately covered by examining a handful of modeled and measured cloud types and a few parameters (optical depth and albedo) is not correct. The amplification of CO2 warming by water vapor is determined by planet-worth of weather such as the oft-trumpeted claim of more numerous storms (a negative feedback). Numerous water vapor modulations must be considered and, more importantly, the external factors like GCR can scramble the entire equation. Thus predictions are by definition a what-if game but those external factors also modulate sensitivity and are not considered at all in the models referenced above.
  5. A Cloudy Outlook for Low Climate Sensitivity
    "Yet, they ignore the warmth of the early and mid 20th century." Camburn, this is patently false. Why dont you read the IPCC WG1 to see how false. "AGW" is not so much a theory as an outcome of the theory of climate - which basically says that climate will respond to whatever is the net value of the forcings present. Funnily enough the forcings (solar, aerosol, GHG) have all varied the last century and climate change has followed our best estimates for what those net forcing were - not just in terms of temperature but also in terms of the fingerprint (summer/winter temps etc) expected. Ignored my foot. Its covered in depth in the published science.
  6. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, reflection (scattering) does depend on frequency. That's why the sky is blue.
  7. A Cloudy Outlook for Low Climate Sensitivity
    Camburn, again this isn't the place to argue about temperature trends, but here is the exact same data you plotted, but with a linear trend added. As you can see, it is not flat - not even close, aside from the fact that HadCRUT shows less warming than data sets which account for the Arctic. But back to the subject at hand, while it's true that these are regional studies, they are of a very critical region. As I quoted from the Stowasser 2006 study, "In terms of the sensitivity of the global-mean surface temperature, almost all the differences among the models could be attributed to differences in the shortwave cloud feedbacks in the tropical and subtropical regions." And climate sensitivity studies do not ignore previous warm (or cold) periods. Quite the opposite.
  8. The human fingerprint in the seasons
    archisteel #87 "I'd also like to point out that *you* picked the higher value for the relative participation of CO2 to the greenhouse effect... " So taking the low value instead, "we" get 0.09 x 0.25 = 0.0225 x 30 = .68 degree"s" C, which apparently accounts for all the world's glaciers to be receding and observed ice melt acceleration in Greenland. Do you believe this?
  9. A Cloudy Outlook for Low Climate Sensitivity
    I am not a good poster but hopefully this will work: http://woodfortrees.org/plot/hadcrut3vgl/from:1995/to:2010 The temperature trend for the past 15 years has been flat. That should be a start for "small extent". And this temp chart brings us back to co2 and climate sensativity as a whole. People will want to point to warming since 1970 as evidence of AGW. Yet, they ignore the warmth of the early and mid 20th century. http://woodfortrees.org/plot/hadcrut3vgl/from:1850/to:2010 It took until the early 1980's to recover to levels exibited in the 1870's and 1940's. And this is getting so far off topic. Look at the temperature graphs. I used hadcrut3 gloabal. Hope that is acceptable.
  10. 2nd law of thermodynamics contradicts greenhouse theory
    No, damorbel, multilayer thermal blankets do not operate solely by reflection. Apparently you really did not read the article you linked to. Go read it. Really, read it. Notice the explanation of the non-reflective mechanism by which it operates.
  11. A Cloudy Outlook for Low Climate Sensitivity
    Camburn wrote : "Show me this evidence that is verifiable and not modeled, but observed." So, I have pointed you towards some observational studies, and the lead article has more, but then you move onto : "Again, I will state that the level of certainty in the models concerning clouds is not there." But what about the observations, then ? You also quickly moved onto : I am thinking on a global scale in regard to studies after first stating : A small area of the world is a start, but we all know regional variances do NOT make climate. What is it, exactly, that you are trying to argue for ? And why do you imagine that "regional variances" have no effect on regional climates ? Camburn wrote : "After all, GAGW is still in the hypothosis stage and has not advanced to theory stage." G(or C)AGW, whatever either of them mean (each so-called skeptic has their own personal views of what they believe AGW means and what they think the 'C' bit means - means nothing to the rest of us) is a strawman. AGW is a theory, as strong as any other theories, e.g. Evolution. Look up the difference between Theory and Hypothesis. Camburn wrote : "Does co2 play a factor in climate. Yes, to a small extent." Can you reveal your sources for that "small extent" ?
  12. The human fingerprint in the seasons
    @AT: I was referring to the study that showed increased heat where it wasn't expected, i.e. the deep oceans. The story about deep lake showing warming is another example of this. I don't have links handy, but I'm sure a quick search on this site would bring the study up.
  13. Renewable Baseload Energy
    Michael sweet, I am aware that reference is pro-nuclear but it had the advantage of other comparisons in that it had numbers for other generation that match what I know to be correct. Do you have a source for nuclear costs that you think has better estimates from an independent authority? Getting subsidy-free, unbiased numbers is really difficult - far more difficult than it should be. As David MacKay has pointed out, you cant have a debate without it being informed by accurate numbers.
  14. A Cloudy Outlook for Low Climate Sensitivity
    @Camburn: temperatures are already at similar levels to that of the Holocene (if you look at the entire globe). "I have read papers that go both plus and minus as far as sensativity. With that in mind, I have to think that the sensativity issue is still wide open." The fact that there exists two points of view on the same issue does not mean the two points of view are equally valid. The fact is that a preponderance of papers argue for high sensitivity, and are supported by evidence, does count. It's not enough to read papers, you also have to understand them and be able to evaluate their merit. The fact you feel the issue is still "wide open" is a clear sign this isn't what you're doing.
  15. 2nd law of thermodynamics contradicts greenhouse theory
    @damorbel: "The Earth reflects back 30% of the radiation coming from the Sun, isn't 30% of the radiation coming from the Earth going to get reflected back in the same way?" You seem to believe that albedo is solely determined by atmospheric (i.e. "above-ground") conditions, but a lot of the actual albedo is determined by the actual reflectiveness of the Earth's surface (water, rock, vegetation, deserts, polar caps, etc.). In that sense, a significant portion of the energy reflected to space cannot be reflected back to the ground, because the ground itself is what's reflecting it.
  16. Ocean acidification isn't serious
    I responds to this over on #148 of "we're heading into an ice age".
  17. We're heading into an ice age
    cjshaker - Note that 100,000 year cycle isnt the main player in glacial cycle - are you seriously suggesting that you dont think the Milankovich cycles are the primary forcing? Modelling of ice age on the whole is fairly crude - running models that are used for predicting the next 100 years over a million years isnt feasible with current computer power, so yes, its still active research. You have competing explanations for the relative importance of various feedbacks in reproducing the cycle and so far no clear winner. For discussion of research and pointers to the papers on the models, then you cant go past Chp 6 of IPCC WG1.
  18. actually thoughtful at 06:45 AM on 6 December 2010
    The human fingerprint in the seasons
    archiesteel - OHC is the last great unknown regarding AGW - do you have recent data or papers which inform your comment "Add to this the fact that oceans are apparently soaking up more heat than we previously thought (even in the deeper layers of the ocean)." I read last week that deep lakes were showing warming (sorry to say I don't have a link).
  19. The human fingerprint in the seasons
    @muoncounter wins the thread, IMHO.
  20. The human fingerprint in the seasons
    I'd also like to point out that *you* picked the higher value for the relative participation of CO2 to the greenhouse effect...
  21. The human fingerprint in the seasons
    @RSVP: there are some issues with your math. First, most of the anthropogenic CO2 rise happened in the last few decades. Second, warming due to CO2 doesn't take place immediately, unlike what your reasoning implies. Combine the two point, and it becomes clear we haven't experienced the full impact of the warming for the *current* CO2 concentration (nevermind from increased CO2 in the future). Add to this the fact that oceans are apparently soaking up more heat than we previously thought (even in the deeper layers of the ocean), and you've got a pretty good explanation why temperatures have only risen by 1C so far. Nice try, though.
  22. 2nd law of thermodynamics contradicts greenhouse theory
    Re #299 Ned you wrote:- "Damorbel, did you ever read the last paragraph of this comment? Did you understand it?" Is this from your paragraph:- "If the albedo of the earth increased, it will receive less short-wavelength radiation (visible, near-infrared). But this doesn't imply an immediate, corresponding reduction in outgoing long-wavelength radiation"? How so? Isn't the outgoing radiation scattered by the same material that scatters the incoming radiation to give the albedo? And further you wrote:- "I'd also note that damorbel has still not explained why he/she approvingly cites an explanation at wikipedia that explicitly relies on the exact same mechanism that he/she thinks violates the 2nd law of thermodynamics." Which is just a multilayer metalised thermal blanket. Thermal blankets don't break any laws of themodynamics because it doesn't matter which way the radiation comes or on its wavelength. They work by reflecting radiation in both directions; a metalised themal blanket doesn't have to be 100% opaque, it could be 30%; reflecting just 30%, same as the Earth. The Earth reflects back 30% of the radiation coming from the Sun, isn't 30% of the radiation coming from the Earth going to get reflected back in the same way? The Earth is not equipped with a one-way mirror that reflects 30% of the Sunlight but transmits its own radiation 100% (making it behave like a black body); no way does that happen in real physics.
  23. A Cloudy Outlook for Low Climate Sensitivity
    As Camburn notes, this really isn't the place to argue whether warmer is better. Nevertheless since the issue has been raised, I will make one comment on the subject. There is quite obviously a point at which warmer is no longer better, otherwise we could live on Venus. I think Daniel Bailey's first graphic in comment #41 illustrates quite nicely that we can no longer use past human civilizations to assess whether "warmer is better" because we're about to move well outside the range of temperatures experienced during those civilizations. "Warmer is better" is a huge oversimplification.
    Moderator Response: Everybody please comment on whether warming is bad on the thread...wait for it...It’s not bad.
  24. The human fingerprint in the seasons
    archiesteel #81 It is my understanding that anthropogenic CO2 comprises 100 ppm of the 380 ppm, which is 26 percent of the 26% you have cited (taking the larger value)... .26 x .26 = 0.068. If greenhouse gases in sum have raised temperatures 30 degrees C, it would appear that the Earth has warmed 30 x .068 = 2.028 C since 1850 or so. Is this the case?
  25. A Cloudy Outlook for Low Climate Sensitivity
    Great post. Very useful, clear and authoritative. Many thanks.
  26. Ocean acidification isn't serious
    Rob I've been reading about dramatic temperature changes in the recent past, documented from temperature proxy data retrieved from the ice cores. http://www.scientificamerican.com/article.cfm?id=ice-core-reveals-how-quickly-climate-can-change "Following this abrupt shift, as much as 20 degrees Fahrenheit (10 degrees Celsius) of warming occurred over the subsequent decades—a change that ultimately resulted in at least 33 feet (10 meters) of sea-level rise as the ice melted on Greenland." http://www.sciencedaily.com/releases/2008/06/080619142112.htm "The ice core showed the Northern Hemisphere briefly emerged from the last ice age some 14,700 years ago with a 22-degree-Fahrenheit spike in just 50 years, then plunged back into icy conditions before abruptly warming again about 11,700 years ago. Startlingly, the Greenland ice core evidence showed that a massive "reorganization" of atmospheric circulation in the Northern Hemisphere coincided with each temperature spurt, with each reorganization taking just one or two years, said the study authors." These seem like pretty massive and rapid climate changes to me. Chris Shaker
    Moderator Response: This discussion has drifted off the topic of this thread. Everybody please start commenting on the appropriate threads.
  27. The human fingerprint in the seasons
    #80: "tangled everything in knots as artfully as the most adept "skeptic."" Ouch. Hardly my intent; most definitely not my meaning. "This makes the statement that "a TSI forcing would not exhibit warmer winters and nights" false." Let's test this idea. Here is a well-known TSI reconstruction: Surely we can agree that this graph shows the period of 1910-1945 or so had a fairly consistent run-up in TSI, what one might call a 'solar forcing'. Now for a temperature anomaly graph, attempting to show summer (green) and winter (red) in the NH, with a sunspot curve (blue) filtered to mimic the shape of the TSI graph. The sunspot curve is normalized to fit on the page and shifted down for clarity. The temp anomalies during this early 20th century TSI forcing have summers (green) warming faster than winters (red). The temp anomalies during the recent warming (which some feel is due to increased GHG concentration) have winters (red) warming faster than summers (green). Hence, a TSI forcing does not exhibit the same signature as a GHG warming.
  28. A Cloudy Outlook for Low Climate Sensitivity
    Nick@40. I feel very lucky. Yooper@41. Ag isn't going to end. This is the end of my off topic additions. We shall save those for threads that talk about the subjects raised that were off topic. Thank you.
  29. actually thoughtful at 06:05 AM on 6 December 2010
    The human fingerprint in the seasons
    Sphaerica @77, Thanks for presenting these points. You said "Any warming, of any sort, will be accompanied by roughly 2C of GHG positive feedback in addition to the initial forcing. That means that any warming will have these same signatures (although to differing degrees)." And then @ 80 "This makes the statement that "a TSI forcing would not exhibit warmer winters and nights" false." These are very interesting points, if true. Elsewhere on this site, based on published papers, the following point is made, which seems to completely contradict your point: "If an increased greenhouse effect was causing warming, we would expect nights to warm faster than days. This is because the greenhouse effect operates day and night. Conversely, if global warming was caused by the sun, we would expect the warming trend to be greatest in daytime temperatures. What we observe is a decrease in cold nights greater than the decrease in cold days, and an increase in warm nights greater than the increase in warm days (Alexander 2006, Fan 2010). This is consistent with greenhouse warming." http://www.skepticalscience.com/its-not-us-intermediate.htm If you can counter that argument, would you post it there, but leave a bread trail here that you did so?
  30. We're heading into an ice age
    Muoncounter: yes, and they talked about tweaking the model to get it to reflect the 100,000 year cycles. I found the whole idea of the ice-sheet bedrock uplift fascinating. I have not yet found newer studies which attempt to model and predict the glacial cycle. Is it still an active area of research? Chris Shaker
  31. Ocean acidification isn't serious
    I remain curious as to why coral are so temperature sensitive Chris, were the Earth (and sea temperatures) not warming so rapidly, it's likely that coral would be able to adapt, by acquiring less temperature sensitive photo-symbionts. Like other changes in the Earth system, it's the speed of change that is the problem.
  32. Ocean acidification isn't serious
    Muoncounter - We don't do photosynthesis. The corals in shallow water reefs are a symbiosis between the coral polyp and photosynthesizing algae. The algae provide nutrients to the polyp via photosynthesis and in exchange get shelter and protection. Typically too warm waters (above the photo-symbiont's tolerance) leads to a shut down in photosynthesis and because they are no longer getting food, the polyps expel the algae, hence the "bleaching" of colours which the algae produce. So although the polyp may not photosynthesize, it is certainly dependent on it for survival.
  33. Ocean acidification isn't serious
    I remain curious as to why coral are so temperature sensitive, considering that they have evolved during millions of years of the glacial cycle? As of 1950, we were still 4.5C short of the temperature high achieved during the previous warming phase. The glacial cycle causes large climate changes. Why have coral not evolved to be more flexible about temperature? Chris Shaker
  34. Ocean acidification isn't serious
    Muoncounter: you might want to read replies from Rob Painting. Coral is a symbiotic organism, basically an algae inside the animal. The algae provides energy for the coral from photosynthesis. Chris Shaker
  35. A Cloudy Outlook for Low Climate Sensitivity
    Re: Camburn Once upon a time, warmer seems to have been better. Let's look at that graphically, shall we? But with what we know of the radiative forcing of CO2 and its status as the Chief Control Knob of Temperatures, consider this graph carefully: At some point we may have to update the top graph with an arrow with this legend:
    "Agriculture ends"
     Let the good times roll... The Yooper
  36. A Cloudy Outlook for Low Climate Sensitivity
    Camburn #39 Possibly warmer might be better in the long run once the climate has settled down to the new equilibrium but there might be horrendous instabilities in the interim period. Do you feel lucky?
  37. A Cloudy Outlook for Low Climate Sensitivity
    dhogaza@36: Past temp proxies and the advancement of mankind indicate that warmer is better. The Golden Age of the Holocene happened at the optimum. Back to clouds tho.
  38. A Cloudy Outlook for Low Climate Sensitivity
    I don't know enough about the physics of clouds to be certain, so I might sound a bit naive by saying the following. Isn't the Lindzen/Spencer scenario that the small increase in planetary average temperature from increasing CO2 will cause the relative humidity to increase, primarily in the troposphere - extra water vapour will be present and will lead to the formation of larger, or more numerous, clouds, which will reflect back sunlight thus cooling us back down in a negative feedback? Where I might be naive is that, as a hang glider pilot, I know, because I have felt it (we're right out in the air flow) that in the gaps between the clouds there is plenty of water vapour too. If Lindzen et al speculate that the feedback from increasing water vapour is negative because of the increase in planetary albedo due to more clouds, have they fully taken into account the increased greenhouse effect from the un-condensed water vapour in the space between the clouds, the area of which is usually much greater than that of the clouds themselves... Comments?
  39. A Cloudy Outlook for Low Climate Sensitivity
    dana1981@34 Thank you. I am thinking on a global scale in regard to studies. I have read papers that go both plus and minus as far as sensativity. With that in mind, I have to think that the sensativity issue is still wide open. I agree. Uncertainty goes both ways. I acknowledge the upper end and the lower end when reading.
  40. A Cloudy Outlook for Low Climate Sensitivity
    "And of course there's always the 'warmer is better' mentality - I'm not sure if the Lindzens and Spencers subscribe to that, but many skeptics do." I don't know about Spencer, but his co-worker and co-religionist John Christy has definitely argued that warmer will be advantageous anyway.
  41. Extreme weather isn't caused by global warming
    #9: "Overall, I bet the so-called skeptics are drooling at the possibility of this coming to pass," JMurphy, you called it. Little did we know just how much drooling is going on. Here is RC reporting this story was a fraud: Coldest Winter in 1000 Years Cometh – not This claim circulates in the internet and in many mainstream media as well: Scientists have allegedly predicted the coldest winter in 1,000 years for Europe. What is behind it? Nothing – no scientist has predicted anything like it. A Polish tabloid made up the story. ... The “climate sceptics” website WUWT, noted for their false reports, takes up the RT piece, presents it together with The Voice of Russia and mentions „Mikhail Kovalevski“. Watts seems to be the bridge for the story´s crossing into the western media. And the stampede was led by the drooler-in-chief. Makes you wonder about just how the so-called 'Climategate' propagated so quickly, too.
  42. The human fingerprint in the seasons
    Oops. Here is the working link to the Kiehl/Trenberth paper.
  43. Renewable Baseload Energy
    @quokka: don't take the expression "sales pitch" negatively. You *are* engaged in pro-nuclear advocacy, so it fact you are selling nuclear energy to this audience. Also, you don't get to determine if you are right or not. That's not the nature of a debate - otherwise everyone would be right, as no one would claim to be incorrect. So you didn't "set the record straight," you argued for your position. Nothing less, nothing more. The "wasteful" arugment simply means you are using a finite resource (radioactive material) when not needed, while neither wind nor solar is finite (at least not for billions of years). Sure, some radioactive elements may be plentiful, but they still require a very complex (and thus expensive) process before they can be used (mining, refining, trasport, security, etc.). All of this adds up. Again, you fall in the same rhetorical trap as Peter Lang: by arguing that Nuclear is the *only* solution, you actually make it harder to sell. Think about it.
  44. A Cloudy Outlook for Low Climate Sensitivity
    Tim the Toolman #11 Er Tim, the stakes are our future. If clouds will save us, a lot of scientists will have egg on their faces. If clouds don't save us then vaya con Dios civilisation. Do you feel lucky?
  45. A Cloudy Outlook for Low Climate Sensitivity
    Camburn - you need to be more careful with your terminology. You said in comment #13 "There is really no evidence one way or another as of yet as to cloud feedback". That is flat-out wrong. In this article alone I discussed 4 studies providing evidence for a positive cloud feedback. You may not be convinced by this evidence, and I'm sure there have been a couple of studies providing some evidence for a small positive or negative cloud feedback, but there is most certainly evidence. And nobody is claiming the issue is settled. As Pete noted in comment #19, the article ends by saying "...much more research of the cloud-climate feedback is needed..." And of course a problem with the "don't regulate CO2 because the uncertainty is too large" argument is that uncertainty goes both ways. There's just as much likelihood that AGW will be majorly catastrophic as there is that it will be benign. Is it possible that a negative cloud feedback will save us from catastrophic warming in the near-term? Certainly. But it's also possible that a positive cloud feedback will drive us toward catastrophic warming in the near-term. Failing to act on the possibility of the latter in the hope that the former is true is extremely poor risk management. It's like driving around without auto insurance because you don't think you'll get into a car accident. Uncertainty is not the friend of the skeptic. The only reason not to act to reduce CO2 emissions would be if we are certain that their effects will be benign. As you clearly agree, we don't have that certainty.
  46. The human fingerprint in the seasons
    @RSVP: By their percentage contribution to the greenhouse effect on Earth the four major gases are: water vapor, 36–70% carbon dioxide, 9–26% methane, 4–9% ozone, 3–7% Sources: Earth’s Annual Global Mean Energy Budget Water vapour: feedback or forcing?
  47. The human fingerprint in the seasons
    66 (muoncounter), You seem to have tangled everything in knots as artfully as the most adept "skeptic." I suspect I introduced some of the confusion by using the phrase "initial forcing," which is redundant, and implies that a forcing is like a quick push. It's not. My intent was merely to distinguish the forcing from the feedback. A forcing is any change that alters the steady state of the system, changing (in this case raising) the equilibrium temperature. A feedback is a change to the system which results from the change in equilibrium temperature, but itself changes the temperature. A positive feedback is a feedback which enhances the initial change (i.e. changes the temperature in the same direction as the forcing). A negative feedback is a feedback which counteracts the initial change (i.e. changes the temperature in the opposite direction of the forcing). Our understanding of the climate system is that regardless of the forcing, there will be positive albedo, CO2 and H2O feedbacks. There may or may not also be cloud feedbacks, which could be positive or negative (we don't know yet). For a solar forcing to raise temperatures, TSI from the sun would need to have increased, and remain increased, just as CO2 levels must increase and remain increased. In no situation is there an "event" or "switch" or "restart" involved. The problem is merely, given a forcing, any forcing which is continuous and as such elevates temperatures, that forcing will be accompanied by strong GHG feedbacks (CO2, H2O) which will carry with them the same signature as a GHG forcing, and those feedbacks are roughly double the size of the initial forcing. This makes the statement that "a TSI forcing would not exhibit warmer winters and nights" false. That's all I'm saying. It doesn't prove or disprove anything. It's just not a valid argument.
  48. A Cloudy Outlook for Low Climate Sensitivity
    @Camburn: "Yes Pete. And since then we still havne't figured out clouds." Look at it this way: clouds may or may not lessen the impact of CO2 on warming. This does not put into dispute the actual CO2 impact, which is well-known. In other words, the uncertainty here is whether or not clouds will mitigate the warming, not if the warming will take place. To take a gamble on clouds that way isn't a rational position, it's wishful thinking (especially when the science tends to indicate they won't). To take my russian roulette example again, betting that clouds *might* mitigate AGW is like hoping that the gun should jam if you pull the trigger and get the bullet.
  49. A Cloudy Outlook for Low Climate Sensitivity
    @Camburn: "I am not possessed with uncertainty." Your posts tell a different story. To you, "uncertainty" seems to be reason for you to think the science is immature. It isn't, and uncertainty wouldn't be a sign it is either. "Does co2 play a factor in climate. Yes, to a small extent." Actually, CO2 is the main control knob of climate. There is ample evidence suggesting this is the case, and very little evidence supporting the idea that CO2 only has a small effect on climate. Or, to put it in a way you will understand, there is much greater uncertainty about CO2 having only a small effect than to the contrary. "Should we use CAGW as the reason to stop burning fossil fuels? Naw....the error bars with the models etc are not up to snuff to do so." That is your opinion, but it is not supported by the overwhelming evidence in favor of AGW. "I look at the science for what is has shown. I see the AGW science as infant and subject to an enormous amount of factors, some known, a lot to be learned. That is why you don't see the public engaged." Actually, the science is far from being in infancy, and the majority of factors are known. Again, you exaggerate how much we don't know. Furthermore, that is not why the public is not engaged. Mostly, the propaganda efforts of Big Oil, who tries to either deny the science, or muddy the issue so much it confuses people about the actual state of the science. As for the Carbon Tax, I think you are confusing this with Cap and Trade. The two are very different. Please explain to me how Goldman Sachs would make money with a Carbon Tax? At least you agree that we should transition away from fossil fuels, but that doesn't mean you are right about the state of the science. It's pretty clear to me that you're not.
  50. A Cloudy Outlook for Low Climate Sensitivity
    Yes Pete. And since then we still havne't figured out clouds.

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