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Comments 100301 to 100350:

  1. CO2 is not increasing
    #8 Tom Dayton http://www.woodfortrees.org/plot/esrl-co2/from:1958/to:2010/plot/esrl-co2/from:1958/to:2010/trend The increase from 1958 to 2010 is a good indication of modern trends in CO2. It is the biggest "cherry " we have accurate data for. Before that the sites jump around and are hit and miss. How do thy correlate and is one the same as another on the same day ? I doubt it. Besides the argument is what is the trend now not 1,000 years ago ? The argument is that since the effect of CO2 is logarithmic and the increase in CO2 is almost linear the rate of warming should slow down in later years. I wish woodfortrees had a handy app for this but they don't. I pulled the CO2 data for 58 years into excel and did a simple log of the data. If the rate is increasing exponentially with a large enough exponent we should see a straight line output indicating increasing warming. The slope should tell us how log it would take to have a doubling of effect. In other words If y=X^2 and T = log(y) In this test case T is a straight line with a steep slope. [About 3/10 ] If this were the case I would agree this would show that the geometric increase in CO2 would cancel out the logarithmic effect of CO2. If however the effective warming [T] is almost flat the world has little to fear. If I take the data set in to Excel and take the log of the 58 years of data I get a straight line with very little slope [.09 / 58 years or .00155 per year ] at that rate a doubling of effect would take thousands of years. Go to the Mona Loa site and download the data and check me. This indicates to me that we have little to fear from CO2 causing rising temperatures for many hundreds of years.
  2. Lindzen and Choi find low climate sensitivity
    Eric (RE: 226), No, I didn't intend it to be a "new" argument. To me, it is such an obvious given. You mean people actually think the climate over hundred years scales is/was mostly a straight line? At any rate, I want to respond to Chris's #222. For some reason, people aren't understanding the argument I'm making. For one they are mixing up and/or intertwining the perihelion/aphelion with seasonal changes.
  3. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Moderator (Daniel Bailey) #35 "You have merely pointed out three areas where the existing theory seeks more robust data, which no one denies." Daniel, you should join the discussion in your own name - I, and no doubt others are not comfortable with players becoming umpires when the game is still going. Skeptics pointing out weaknesses and inconsistencies in AGW theory does not oblige them to offer a better fit theory to the observations. After all, it is the proponents of AGW who urge immediate drastic action to reduce CO2 release from fossil fuel burning and massive economic cost in converting to 'green' alternatives. The skeptics are not urging any such radical action. So it is for the proponents of such action to prove their case. What you are implying is that the standard of proof is to be decided by the fabled 'consensus' of independent researchers. I would agree that 'beyond reasonable doubt' is probably too tough a standard - because there is already 'reasonable doubt' in key areas such as I exampled in #15 and that it might take much more extensive data and research to achieve that standard if ever. 'Balance of probabilities' is a much lesser hurdle and the AGW theorists would argue that they have already achieved that standard. Scientific theory is not proven by ballot however. The issue is whether or not there is a single (or two) contraverting pieces of robust observation which undermines the current AGW theory and points in a different direction. The answer will probably be found in measurement of OHC.
    Moderator Response: [Daniel Bailey] It is the moderators job to keep threads on-topic. The topic of this thread is whether it is safe to double atmospheric concentrations of CO2. Your 3 items you flagged in your comment 15 above were on ocean acidification, OHC and SLR (all off-topic here). The burden is on you to find the appropriate threads for those and to posit a physics-based alternative to AGW specific to each of your concerns, as you have been repeatedly told in the past. If you wish to be taken seriously here, you will do so.
  4. Dikran Marsupial at 21:11 PM on 25 December 2010
    Do high levels of CO2 in the past contradict the warming effect of CO2?
    Eric (skeptic) @ 14: The CO2 could not have come from the oceans as they were iced over and hence disconnected from the atmosphere. However this means that the oceans were no longer removing CO2 from the atmosphere either*, and mineral weathering on land was also reduced by ice cover (as mentioned earlier in the thread). This means that the relatively small amounts from volcanic eruptions would just accumulate in the atmosphere until the greenh ouse effect was high enough to start melting the ice. Once that happened, there would be feedback from decreasing albedo and from increased water vapour, so it is unlikely that CO2 alone was responsible for the emergence from the snowball Earth. *The exchange of CO2 between the atmosphere is not governed only by temperature, it is also governed by the difference in partial pressures between the atmosphere and the surface waters, so all things being otherwise equal, the oceans would try to remove excess CO2 from the atmosphere (by becoming a net carbon sink), as they are doing now.
  5. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Humans aren't actually that good with risk, and there are a range of reasons for the current situation that I could not do justice to. For example, we typically engage in what the risk managers and economists call 'future discounting' for issues whose consequences are not immediate. We also suffer from confirmation bias. For the case of the red berries, if they made us feel violently ill then sure, we would probably stop eating them. Then again, if the berries made us feel violently ill- but only the day after they made us feel euphoric, and they were addictive, then we may suddenly find our rational judgement of the risk is compromised. Again still, imagine if we could easily see carbon dioxide emissions; from cars, boilers, industrial plants, power stations and even in the color of the sunset. In that instance we may well have taken a different view of the risk. We delude ourselves all the time. That is exactly why we collect data and do science. The point of my article is that I think we need to adopt the correct risk framework whenever we communicate our science, and remind people that science can do this type of thing very well. You wouldn't get on an airplane otherwise.
  6. Dikran Marsupial at 20:49 PM on 25 December 2010
    Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    cloa513@1 You are completely wrong about food safety. A number of years ago I took part in a government funded project on the potential hazards associated with eating potatoes, a food mankind has been eating in quantity for a very long time. Potatoes produce glycoalkaloids in response to sunlight and/or physical damage, as a defence mechanism, and it is possible to poison yourself by eating potatoes. However the risks are small as most people know not to eat green or damaged tubers or tubers that have been stored for too long, and glycoalkaloids have a bitter taste so it is detectable. You may not be aware of research into the safety of foods, but that doesn't mean it doesn't exist.
  7. CO2 is not increasing
    Here's a good illustration of the changes in atmospheric CO2 concentration over time (h/t to Lou Grinzo for alerting me to this much-updated animation): You can literally watch the Earth "breath"... The Yooper
  8. Do high levels of CO2 in the past contradict the warming effect of CO2?
    muoncounter and Daniel Bailey, thanks, I'll look at those some more tomorrow. On first glance though, those factors are not sufficiently quantified into CO2-doubling-type forcings to get a sensitivity number out of the graph above (not to mention poor granularity, not much of a temperature proxy shown on the graph except glaciated and not glaciated, etc). It might speak to the general argument but is not quantifiable.
  9. Conspiracy theories
    I've posted a response to NETDR's claim that CO2 is increasing only linearly rather than exponentially on a far more relevant thread: "CO2 Is Not Increasing."
    Moderator Response: Good idea; everybody take discussion of that topic to that thread (CO2 is not increasing).
  10. Lindzen and Choi find low climate sensitivity
    RW1, I think your new argument in this thread "I was under the impression that you and everyone else here knows that the climate doesn't do anything but change" is not going to go over too well. For starters there are several threads and hundreds of posts that discuss that topic and rebuttals. If you didn't intend to propose that as a new argument, then you probably need to be more specific. I have done that same thing in the past and probably will do it again by responding to what may seem like a tangent to me, but isn't.
    Moderator Response: Thanks for helping keep the discussion on topic! For this particular one, how about everybody go to "Climate’s changed before."
  11. Do high levels of CO2 in the past contradict the warming effect of CO2?
    Re: Eric (skeptic) (14) The biggest obstacle to finding a "smoking gun" (causative mechanism) to end the ice age in question is the granularity of the measurements. Unless we find a datable proxy that catches a mechanism "in the act" we may never know for sure. An example of a postulated "quick" mechanism would be the methane clathrate gun. Recent evidence has been found to support such a mechanism (see free copy here). By no means am I postulating this mechanism is the specific one to end the ice age in question. Just wanted to point out one possible mechanism. Hope this helps, The Yooper
  12. Conspiracy theories
    "In fact until 1978 or so when satellites were launched we had little clue of temperatures up there." Satellite data used for temp reconstruction don't include the Arctic. Gosh, how many time do you want to be wrong in a public forum?
  13. Conspiracy theories
    "Claiming this very slight upward trend offests logarithmic effects of CO2 would be counter-factual." Not at all, the first doubling from industrialization hasn't happened yet, and won't, for some decades. The CO2 forcing and exponential increase in CO2 accumulation are happening on roughly the same time scale. You're starting to be very boring, much like those who argue the earth is flat, or 2+2=5, or pi=3, etc.
  14. Conspiracy theories
    "The rate of accumulation of CO2 is almost linear" Sure, exponential increase can look like that. While it's still exponential ... It's all about timescale. At least you're honest enough to admit it's *not linear* ("almost linear" means "not linear"), despite your subsequence display of ignorance (i.e. that over short terms, an exponential function closely matches a linear one).
  15. Lindzen and Choi find low climate sensitivity
    muoncounter (RE: Post 223), I'm sorry, I was under the impression that you and everyone else here knows that the climate doesn't do anything but change. You do understand that even if mankind never emitted a single CO2 molecule, that the climate would still be doing what it has always done - change (go through periods of warming and cooling, etc.)?? A roughly 0.6 C sensitivity is at least as consistent with a 0.8 C rise so far, and probably more so, because 0.8 C is much closer than 3 C.
    Moderator Response: Comment on that topic in the relevant thread: "Climate’s changed before."
  16. Lindzen and Choi find low climate sensitivity
    KR (RE: Post 223), The gain is not a subjective number or "my gain". It's a very simple objective number. You have power coming in from the Sun. Some of that power is reflected back out via the Earth's albedo. The rest of the power "forces" the climate system. The amount of power at the surface is greater than the post albedo power entering the system from the Sun and greater than the power leaving the at the TOA. The surface power divided by the post albedo power is the gain in the system. It's simply a representation of what about each 1 W/m^2 of power coming in is amplified to at the surface due to the greenhouse effect. Power from the Sun is measured in W/m^2. Increased power from CO2 is measured in W/m^2. A watt/meter squared of power is watt per meter squared of power, independent of where it comes from; thus power from the Sun is proportionally the same as power from CO2.
  17. CO2 is not increasing
    This is my response to a comment by NETDR on another thread, as my attempt to move that conversation to this appropriate thread. Tamino wrote an excellent post demonstrating that CO2 rise is exponential, not linear.
  18. Comparing all the temperature records
    Norman said, From 1998 to 2010 the temp trend is negative...cooling phase. OK, Norman... here's an interesting exercise to try. Compute temperature trends for that length of time starting at 1980 and incrementing by 1 year for each new trend computation. (That is, compute the 1980-1992 trend, the 1981-1993 trend, the 1982-1994 trend.... etc, up to the 1998-2010 trend). How much variability do you see in your trend computations? What does that tell you about the robustness of trend computations for such a short time period?
    Moderator Response: [Daniel Bailey] Fixed text.
  19. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Ken Lambert said, Deep mixing of the ocean layers is inconsistent with suface layer acidification. Someone here is completely overlooking the concept of time-scales...
  20. Lindzen and Choi find low climate sensitivity
    RW1 - Sorry, your gain makes no sense whatsoever to me. The energy trapped at the surface is a function of the insolation and the ability of the Earth/atmosphere system to radiate that heat away in a temperature dependent fashion. I think we are all much better served by using the actual relationships there rather than a non-physics based 'gain factor' that isn't actually a constant. There's no difference between insolation changes, aerosol changes, albedo changes, and CO2 changes in terms of forcing beyond their "efficacy", and the only factor with an efficacy close to 1.6 in anyone's estimation (and I consider that an outlier) is cloud albedo (Figure 2.19).
  21. Conspiracy theories
    #65: "rate of accumulation of CO2 is almost linear." Interesting; you like the simplest possible answer to science questions, but you'll find the most convoluted interpretation of events and motivations to form your conspiracy theories. That's a hallmark of skeptics: reduce complicated issues to sound-byte size chunks, then repeat the sound byte, even when they are debunked. Very productive. The annual rate of change in atmospheric CO2 concentration is increasing; it was 1 ppm/year in the early days of the MLO record, but its been over 2-2.5ppm per year for several years now. It tracks CO2 emissions from fossil fuel consumption quite well. The recent recession dropped US CO2 emissions slightly in 2009, but didn't faze China and India. Add in the Law Dome CO2 and you have a rapid rate of increase over a short period of time, and yes, that does overcome the log relationship of forcing vs. relative CO2 concentration. A graph of temperature change due to CO2 forcing vs. time is concave up, meaning it has an increasing slope. The rest is off-topic. If you want to debate changes in the Arctic, there are plenty of active threads on that topic. But if 'we had little clue' is all you've got, I wouldn't advise it.
  22. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Rob H #22 "Small unexplained elements of a theory do not undermine a theory." The three 'inconsistencies' I listed are not 'small'. They go to the heart of AGW theory. What you are suggesting is the 'its there but we just can't measure it' argument which can hardly be called scientific rigour.
    Moderator Response: [Daniel Bailey] Per Rob's comment at 22 above, in order to prove a theory wrong you need to have a competing theory that fully explains all current observations. And it needs to explain them better. You have merely pointed out three areas where the existing theory seeks more robust data, which no one denies. Conflating that into "since we can't know everything therefore we can know nothing" serves no useful purpose. Nor does it add anything to the dialogue, as has been pointed out to you repeatedly on other threads. Please come up with a viable physics-based alternative to AGW which explains what we have known about GHG's for over 150 years which also explains why anthropogenic CO2 doesn't act like the GHG that CO2 already in the carbon cycle does. That would be displaying scientific rigour. Anything less is sophistry.
  23. Do high levels of CO2 in the past contradict the warming effect of CO2?
    #14: "not with today's ocean turnover rate." Why would you use today's anything rate when talking about 450 mya? The continents were in a completely different configuration; oceanic circulation was vastly different. Here's evidence that the Ordovician ice began forming in a much lower CO2 environment: the evidence suggests that the ice began to build up some 10 million years earlier than when volcanoes began pumping the atmosphere full of the CO2 that ended the Ordovician ice age. "... sounds plausible and simpler. " The answer to this question will not be found in a simple one-size-fits-all model.
  24. Conspiracy theories
    #64 The rate of accumulation of CO2 is almost linear. http://www.woodfortrees.org/plot/esrl-co2/from:1958/to:2010/plot/esrl-co2/from:1958/to:2010/trend #Least squares trend line; slope = 1.43127 per year Admittedly there is a very slight upward trend but worldwide recessions have a way of periodically reducing CO2. Claiming this very slight upward trend offests logarithmic effects of CO2 would be counter-factual. The CRU data set is the longest one we have and arctic temperatures in 1860 are non existent on any data set. In fact until 1978 or so when satellites were launched we had little clue of temperatures up there.
  25. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Due out in print Jan 2011 How Safe Is Our Food?. An advance Epub from the CDC.
  26. Do high levels of CO2 in the past contradict the warming effect of CO2?
    muoncounter, thanks for the info. My question was narrower, I just wondered if there was a known CO2 source for the increase 445m years ago in the chart above. dhogaza, it could have come from the oceans, but not with today's ocean turnover rate. Since it took millions of years to vent out (although I'm sure the chart above is fairly crude), the ocean turnover would have to be very slow to very slowly warm and thus very slowly release its CO2. Such slow turnover may be possible with the continents arranged the way rockytom pointed out. Tom's explanation in #11 also sounds plausible and simpler.
  27. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Rob #32 I agree with the point you are making Rob. I simply wanted to point out that food safety is far less than one might expect, making it a poor example (i.e. 4 of 186 restaurants in my city passed inspection with a full 25% being red carded). Sashimi anyone?
  28. Conspiracy theories
    Of course, not only does NETDR cherry-pick his time intervals, he cherry-picks his dataset. http://www.woodfortrees.org/plot/hadcrut3gl/from:1860/to:2010/plot/hadcrut3gl/from:1880/to:1910/trend/plot/hadcrut3gl/from:1940/to:1975/trend/plot/hadcrut3gl/from:1998/to:2010/trend If you use GISTemp things look quite different. As we all know, GISTemp includes an estimate of temperature anomalies in the Arctic, which is warming faster than the rest of the planet, while HADCrut does not. And, of course, climate scienctists understand that CO2 forcing isn't the only thing that impacts temperature, but also that as CO2 forcing increases its effect on temperature is slowly becoming more important than natural variation, one reason why the last 12 years are the warmest on record despite our being in a deep solar minimum. "The rate is gentle and irregular and should slow since the effect of CO2 is logarithmic. So unless the input increases geometrically the rate will slow and it is already too slow for a catastrophe." Exponential, actually, and that happens to be what's happening. NETDR, meet the Keeling Curve
  29. Conspiracy theories
    More grasping at straws to support your conspiracy notions. The links section of this site currently shows 396 articles supporting the "it's cooling" argument. The logarithmic effect is being countered with an exponential growth in anthropogenic emissions. Any other conspiracies you want to bring out in to the light?
  30. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Ron Crouch @ 27... Likewise, there are a great many well tested aircraft that have left the ground with many souls on board not to make it safely back to earth. The point being that everything has risk. Getting out of bed in the morning carries with it risk. But we take great pains to make sure that the things we do involve acceptably low levels of risk. This is the point of the article. At this point the risk models are high and yet we proceed each day as if there were no risk at all. There is one aspect of the risks that I don't think is addressed here. Slow and fast. Eating poisonous food or a crashing airplane is an immediate catastrophe. Climate is a very slow progressing catastrophe. If you are 60 years old today you will likely not see the worst of what is to come. If you are 20 today your situation is vastly different. As well, if you live in a poor nation you are more likely to be affected than if you live in a wealthy nation. The risks involved are very unevenly distributed.
  31. Conspiracy theories
    It has warmed. Who says it hasn't . The rate is gentle and irregular and should slow since the effect of CO2 is logarithmic. So unless the input increases geometrically the rate will slow and it is already too slow for a catastrophe.
  32. Conspiracy theories
    1978 - 1998 is only 20 years. No matter how hard you insist otherwise, the world has still been warming. The hottest 12 years on the record are the past 12. Do you have a conspiracy notion about that too?
  33. Conspiracy theories
    Dhogaza #59 The point I was making is that if we have a 30 year cooing or lack of warming the catastrophe in CAGW is nonsense. Notice that it took until 1980 to get as warm as 1940. That has to hurt the overall warming. I was surprised to find that the steep 30 year period from 1978 to 1998 was only 1.2 degrees per century. That was with ocean currents very high sunspots and a monster El Nino. Mother nature was helping all she could and the rate was still low. The reason the last period is only 12 years long is obvious, I will post the rest in 18 years.
  34. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    In science you cannot "prove" anything, but you can disprove it. The onus is on the skeptics to disprove AGW. Despite having well over 100 year to do so, the "skeptics" have been unable to refute the theory of AGW/ACC, or offer a reasonable alternate theory that has withstood scrutiny.
  35. A basic overview of Antarctic ice
    Has Antarctic Ice been similiar in the recent past? Yes it has, and in fact has prob been lower. http://geology.gsapubs.org/content/38/7/635.abstract?sid=0f422966-63d5-4963-895f-b8a3935beb2d
  36. Conspiracy theories
    "Mojib Latif seems to think that in short time scales like 60 years natural variation is more important than CO2" Mojib Latif has complained loudly and visibly about his views being misconstrued by climate change denialists such as yourself. Please refrain from doing so here. He merely points out that on short time scales like a *few years* (note the lack of caps), not *60 years*, natural variability can swamp the long-term signal. He understands that over periods of two to three decades the signal expresses itself. As for your wood for trees plot, cherry-picking can get you any result you want. Yet, it's interesting that in order to get your result, your first series (1880-1910) is thirty years long and shows a fairly steep decline, your second (1940-1975) is 35 years showing a very slight decline, while your last (1998-2010) is 12 years and is essentially flat. So your own cherry-picking shows these "stalls" in warming switching from leading to a fairly steep decline before anthropogenic CO2 began to kick in in earnest, a slight decline in the 1945-1970 period, and a flat period which you could only get by cherry-picking a short 12 year period. In other words, totally consistent with increased CO2 forcing increasing warming, ...
  37. CO2 was higher in the past
    Shouldn't the title of the article read "DO high levels of CO2 in the past contradict..." (instead of does)?
  38. Lindzen and Choi find low climate sensitivity
    RW1 at 05:24 AM on 25 December, 2010
    "How do you figure we've had all the warming of a 2 C sensitivity?"
    Come on RW1, this was explained here, and here, and here. Remember we're using your own argument, (but doing it correctly). It's very straightforward (use the equation here) to determine the full warming expected at equilibrium from the rise in [CO2] between 1900 and 2000 (the dates you chose yourself). [CO2] in 1900 was 298 ppm. [CO2] in 2000 was 371 ppm. The warming at equilibrium for 3 oC climate sensitivity is 0.95 oC. The warming at equilibrium for 2 oC climate sensitivity is 0.63 oC. The actual temperature rise during this period was 0.75-0.8 oC. In other words we've had all the warming already that we expect from a climate sensitivity of 2 oC (Earth surface temperature rise per doubling of [CO2]), even though the Earth surface hasn't come to equilibrium with the enhanced greenhouse forcing during this period, and even though some of the warming has undoubtedly been countered by the large increase in made made aerosols. We know the solar contribution to warming has been small during this period (very likely less than 0.1 oC) as the very competent solar scientists inform us [see e.g. Lean and Rind (2008) and Hansen et al (2005)]... (and if were being very careful we should factor in the small contribution from man-made rises in methane and nitrous oxides atmospheric concentrations). So your assertion that 20th century warming is "in line with about a 0.6 C upper limit from a doubling of CO2" is clearly incompatible with empirical observations. That should contribute a warming of 0.19 oC at equilibrium from the 20th century rise in [CO2]. If your assertions are so wildly at odds with empirical observations RW1, then there's something very wrong with your argument.
    "How about you explain why the sensitivity numbers I've put forth fit very well with the temperatures differences at perihelion and aphelion..."
    I expect the numbers (you got them from someone's website I think) match rather by chance, unfortunately. It’s clear that you haven’t made any headway with your numerology with the set of rather bright individuals who have tried to help you out on this thread! In any case, the dominant effect on the relative hemispheric warming/cooling at aphelion and perihelion is the relative amount of land (low heat capacity) and ocean (high heat capacity) in the two hemispheres. Since the sinusoidal seasonal solar forcing is paced much faster than the Earth (and especially the oceans due to its high heat capacity) can come towards temperature equilibrium with the rapidly varying forcing, there is a strong mismatch between the rates that the hemispheres gain and lose heat. The N hemisphere (lots of land) warms more quickly than does the S hemisphere (90% ocean). Clearly, if one were able to determine climate sensitivity from analysis of the seasonal response to insolation variation there would be a nice body of scientific literature on the subject! There isn't. Unfortunately these analyses are bedevilled by difficulties in determination of the characteristic time constant of the climate system response to forcing. More importantly, the response to the very rapid (monthly) changes in insolation during the Earth's speedy passage around the sun, means that only the elements of the climate system that respond more rapidly are (partially) sampled (atmosphere and land surface). So as described in Foster et al (2008), for example, analysis of transient responses to rapid changes in forcing generally produce climate sensitivities that are biased low relative to the climate sensitivity of interest, namely the full Earth response to a strong, persistent (and progressively increasing) enhanced greenhouse gas forcing.
  39. It's Pacific Decadal Oscillation
    These subjects blend from one subject to another. How can a conversation with many elements possibly take place ? I came over to the PDO thread but the recovery from the LIA is part of the story. Carrying on a conversation with both elements is impossible and frustrating. #33 The warming may even be due to CO2 who cares ? The overall warming is about 1/2 ° C when the periodic cooling is taken into account. When the maunder minimum was over we started to measure temperature. Thinking all warming was caused by mankind seems contrary to fact. Positive feedback if it exists would multiply solar effects by 3 or more, but it might take time for them to build up. Notice the sunspots increased slowly until the late 2000's, it is an integration not an instantaneous phenomenon. http://sidc.oma.be/html/wolfaml.html
  40. Conspiracy theories
    #56 Bibliovermis To me the sine wave is clearly visible. Saying that it would be the consensus view if it were rue is meaningless. Many skeptics like Spencer have written about it also ! Here is even a paper from the University of Alaska which explains it. http://people.iarc.uaf.edu/~sakasofu/pdf/two_natural_components_recent_climate_change.pdf Here is the data, notice the cooling in 1880 - 1910, 1940 - 1978, and 2000 - present. [Actually the last is lack of warming not actual cooling yet.] Notice that the cooling cycles start about 60 years apart. Mojib Latif seems to think that in short time scales like 60 years natural variation is more important than CO2 and this graph seems to substantiate it. Over the long term there is warming, no doubt but the periodic cooling cycles make a mockery of the catastrophe in CAGW. Here is the temperature from 1860 to present. The 60 year trend is clearly visible to me. I can't understand why you can't see it. http://www.woodfortrees.org/plot/hadcrut3gl/from:1860/to:2010/plot/hadcrut3gl/from:1880/to:1910/trend/plot/hadcrut3gl/from:1940/to:1975/trend/plot/hadcrut3gl/from:1998/to:2010/trend #57 Mouncounter Notice that they all are tenured. For a young person starting out it wouldn't be a good career move. Accepting research funds from big oil would be career suicide.
  41. It's Pacific Decadal Oscillation
    #30: "ramp is because of recovery from the Little Ice Age" Even positing that's true for just a sec, what would cause such a thing? "the sine wave is caused by ocean currents. [ADO and PDO]" Which you just said, cannot cause warming. What's nice about AGW as a scientific theory, other than that it's real, is that it explains observed phenomena. Which is important in science. Otherwise, you're just making stuff up.
    Moderator Response: Everybody comment on recovery from the Liitle Ice Age on that thread, not this one.
  42. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    #21: "during a period of maximum CO2 potency, they have risen at a rate of 0.64degrees C per century, and currently show every indication of slowing down." Do try to keep your facts straight. O.14 deg C per decade on the low end; 0.4 deg C per decade may be the new norm. See Assessing global surface temperature. As for 'every indication of slowing down', look here, where the most recent 30 year trend is in excess of 0.5 deg C/decade: that isn't an indication of slowing down. Comments regarding temperature records alone -- off topic for this thread -- should go to one of those or one of the many similar threads.
  43. Lindzen and Choi find low climate sensitivity
    #218: "...a representation of how much can be expected to be added on top of natural variation from 2xCO2." There's not currently a 'natural variation' that is doubling CO2. If your model is due to the effects of CO2 only, why do you start with planetary albedo and continue with emissivity? These points of basic physics are not CO2-specific. "The amount of warming we've seen so far is perfectly in line with about a 0.6 C upper limit from a doubling of CO2." Utterly incorrect and shown a number of times in this thread. Look at hfranzen's article; he arrives at 0.14 deg C/decade, which is far more than an 0.6 C sensitivity can produce. His results come from a strictly physics-chemistry calculation. You can't both be correct -- and his work agrees with measurements of temperature increase.
  44. Conspiracy theories
    #53: "things happen so slowly that incorrect beliefs aren’t punished for 30 years" That's just ridiculous. Response to a nonsensical hypothesis is swift and sure, thanks to this very medium. Unfortunately, good people get trashed, even before their papers come out in print. "Going along with the consensus is the best career choice in climatology." Then why, according to the deniersphere, are there so many climate scientists who reject AGW? Or is that just another conspiracy? As for your 'sine and ramp theory idea, perhaps you could email it to John who could post it here.
  45. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Long before we had modern science, one of the ways we know whether food was safe was by watching what happened to our neighbour when they ate those tempting red berries. If only we had a neighbouring planet that had quickly consumed all its coal deposits; then we wouldn't need all those GCMs, we could disband the IPCC and James Hansen could spend more time with his grandchildren. Those red berries tasted nice, perhaps the fever that I'm starting to experience means that I should just eat more of them. Um, why are those alien neighbours watching me so closely?
  46. Do high levels of CO2 in the past contradict the warming effect of CO2?
    #8: "how we got out of the glacial conditions 400m years ago." #10: "where does the CO2 come from?" A large quantity of CO2 was removed from the atmosphere/oceans during this point in the geologic past. It's not a question of where it came from (may have been 'primordial'), but where it went: The widespread deposition of Ordovician marine carbonates (CaCO3) in warm shallow seas.
  47. Lindzen and Choi find low climate sensitivity
    johnkg (RE Post 219), Your maths or STILL wrong. CBDunkerson put you right on that way back in post #34. And I then clarified in Post 96 I was referring to the intrinsic response of CO2 - not any additional increase as a result of feedbacks. My statement in #218 is accurate.
  48. It's Pacific Decadal Oscillation
    Re: netdr (30) Akasofu commits many an error (multiple violations of the top 10 in the upper corner of this page). Trenberth has demolished Akasofu's credibility in the past, as shown here. You grasp at straws, as Bibliovermis details above, and as Stephen Leahy alludes to in his comment here. The Yooper
  49. Is it safe to double atmospheric Carbon Dioxide over a 200 year period?
    Fred Staples said: Now what will happen if the absorptivity of the atmosphere increases again? Nothing will happen. If the atmospheric temperature increased, the outgoing energy to space would be greater than the incoming energy, and it would promptly cool down again. OK, what part of the atmosphere radiates IR directly to space? And as the CO2 concentration increases, what happens to that part of the atmosphere? How will that impact the average temperature at the Earth's surface, and why? If you have even a *very basic* understanding of atmospheric physics, these should be slam-dunk easy questions for you to answer
  50. Conspiracy theories
    Positing a 60 year temperature cycle that the scientific community is either purposefully ignoring to keep their funding flowing or is too incompetent to see is a perfect example of what this entry is discussing.

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