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RSVP at 04:45 AM on 26 July 2010Rebutting skeptic arguments in a single line
to doug_bostrom All I ask is how transparent gases radiate. I am being told that IR sensitive CO2 in the mixture heats it, and this is the main cause of global warming. -
DarkSkywise at 04:11 AM on 26 July 2010The nature of authority
AWoL at 03:42 AM on 26 July, 2010: Why would a logician assume that multiple, independant lines of evidence would indicate an agenda? That's, erm, not logical. ;) -
werecow at 03:54 AM on 26 July 2010Assessing global surface temperature reconstructions
Very nice post! Just out of curiosity, what was the reason for the large size of the 2008 GHCN adjustment? -
RSVP at 03:43 AM on 26 July 2010The nature of authority
To doug_bostrom "Yet by "chance" this same force was invented as self-aware" Somewhere I heard that intellegence evolved through generations of escalated deception. -
AWoL at 03:42 AM on 26 July 2010The nature of authority
Sweet, Michael..... Given that Darwin was a consummate logician, I take a different stance to yours and submit to all, that he would have pronounced the AGW agenda as the most intellectually flawed load of B-ll-x he'd ever encountered.....more the remit of the snake-oil salesman than that of the scientist, formerly respected, until those times, as a pillar of rectitude and intellectual integrity, supporting the grand edifice of enlightened European civilisation. -
Doug Bostrom at 03:35 AM on 26 July 2010The nature of authority
Nature innovates, in fact innovated a force that could for instance eliminate the ozone layer and thus inflict what by some measures would be a swift and catastrophic change in conditions on the surface of the planet. Yet by chance this same force was invented as self-aware and thus capable of changing its own behavior at will, thereby reversing its previous course with regard to removing the ozone layer. Marvelous, when you think about it. -
Doug Bostrom at 03:30 AM on 26 July 2010Rebutting skeptic arguments in a single line
"According to AGW, N2 and O2 are transparent to IR." That perspective captures nicely the brick wall we face in driving discussion forward. For reasons unrelated to science this is an Intractable intellectual hurdle, but let's remember, radiative physics and for that matter the known properties of elements at the level of understanding mentioned by RSVP are not a theoretical byproduct of people exploring the concept of anthropogenic warming. A better way to express the situation is that the notion of anthropogenic warming is a seemingly inevitable outcome of previous, fundamental research conducted without any particular motivation other than improved understanding of the natural world. Changing any minds, here? No, absolutely not, I'm sure. All the same I'm compelled to try and check in some microscopic way the cultural dementia fostered by from getting things backwards in the way RSVP does. -
RSVP at 03:28 AM on 26 July 2010The nature of authority
to michael sweet Looks like we were thinking something similar, however why should Darwin think AGW is a problem? Evolution guarantees survival of the fittest. -
RSVP at 03:23 AM on 26 July 2010The nature of authority
"Charles Darwin,as a die-hard gradualist and staunch supporter of Lyell's uniformitarianism, himself would have been a skeptic of AGW, I suspect." The connection is not so clear (to me), since AGW is by definition not a process of Nature. -
AWoL at 03:21 AM on 26 July 2010Rebutting skeptic arguments in a single line
Most excellent job,RSVP. -
michael sweet at 03:15 AM on 26 July 2010The nature of authority
Thingdonta, Most of us agree with Darwin that NATURAL changes are usually gradual. AGW is anthropogenic, so it is fundamentally different. I think Darwin would follow the data, like the majority of scientists, and agree AGW is a problem. Since he is dead we will never know for sure. -
DarkSkywise at 02:51 AM on 26 July 2010Assessing global surface temperature reconstructions
Nice job, Ned! -
RSVP at 01:41 AM on 26 July 2010Rebutting skeptic arguments in a single line
Ned, By changing just one word, you end up with... ...CO2 is somehow very important and needs to be talked about constantly, despite being a microscopic fraction of the atmosphere... ------------ There is nothing extraordinary about the convective cooling of heat engines. Absolutely every calorie removed from an engine to cool it, ends up in our atmosphere. According to AGW, GHGs absorb and emit IR, yet 97% of the atmosphere is not GHG. According to AGW, N2 and O2 are transparent to IR. I am not aware of a century of laboratory measurments dealing with this issue. Are you? Maybe this is what needs to be talked about. -
Tom Dayton at 01:38 AM on 26 July 2010It's Pacific Decadal Oscillation
ptbrown31, you have missed the point. You wrote that "it is assumed that the PDO is not effecting (sic) global SSTs," and "this is not a robust conclusion." The Pacific Decadal Oscillation does what, by definition? It oscillates! That means it goes back and forth--reverses course, then repeats. Its lack of a non-oscillating component is neither an assumption nor a conclusion, but part of its very definition. You have misunderstood the skeptic argument that blames the PDO for the "apparent" global warming long trend. That skeptic argument is not that the PDO has a long-term warming trend. Rather, the skeptic argument is that no long-term warming trend exists. At all. The skeptic argument is that the PDO's warm phases have been long and frequent enough that climatologists have mistaken them for long-term warming. The skeptic argument is that if we simply wait a bit longer, we will see PDO cooling phases long enough to wipe out all the warming we've seen since the 1850s. The counterargument is captured in the figure that you objected to. PDO warm phases are much too short to be responsible for the warming we've observed since the 1850s. There already have been counteracting cool phases. -
thingadonta at 01:27 AM on 26 July 2010The nature of authority
#96. Good quote from Charles Darwin. But just to note, Mr Darwin was also a gradualist, who certainly didn't believe that significant geological changes (such as catastrophic climate change) occurred within the time frame of human lifetimes. He strongly opposed Cuvier's assertion that mass extinctions occured in the geological record. (Darwin was wrong). He strongly opposed the notion that climate, and its effects on biota, can change rapidly. (Darwin was wrong). Both he and Lyell believed Earth history was fundamentally 'stable' or uniform, and not prone to catastrophic 'convulsions' and such like, and therefore they rejected any notion that massive species turnovers ever occurred (They were wrong). The gradualists were fundamentally opposed to the catastrophist assertions that both significant geological 'upheaval' and biological evolution could occur within the general time frame of human history. (This was partly in response to the 'flood' catastrophists). Various geological debates between catastrophists and gradualists have been going on for several centuries. In biology, gradualism has generally gained predominance, however there are major exceptions (eg punctuated equilibrium and debates, mass extinction events etc etc). However, I certainly think that contemporary thought on climate change has been over-dominated by 'catastrophist' assumptions (without those advocating AGW actually realising that that is what they are, and that is where their assumptions on earth dynamics lies); some redress is definitely needed. Charles Darwin,as a die-hard gradualist and staunch supporter of Lyell's uniformitarianism, himself would have been a skeptic of AGW, I suspect. -
DarkSkywise at 00:56 AM on 26 July 2010What do you get when you put 100 climate scientists in a room?
"(although you're welcome to post a punchline in the comments if you can come up with a funny answer)" Knock knock. Who's there? 90s Evan. 90s Evan who? 90s Evan Purscent of all climate scientists. :P I also asked Cleverbot: "What do you get when you put 100 climate scientists in a room?" but the answer was: "I don't know." (Apparently, that part of science isn't settled yet.) -
JMurphy at 23:14 PM on 25 July 2010What do you get when you put 100 climate scientists in a room?
gallopingcamel, if you want to go around in circles, ignoring the truth, fair enough. I, however, will just repeat what I have already asked (and which you don't seem able to answer : To show that you have actually read the judgement, please state what you mean by "Stewart Dimmock (the truck driver) won his case challenging Al Gore's book". And what was the "correct conclusion" drawn by the UK judge - as you see it in the written judgement ? I will add one more to the questions that you cannot answer : Please list the "11 issues mentioned in his book" that you found in the text of the judgement. -
JMurphy at 23:08 PM on 25 July 2010The nature of authority
Ken Lambert, give it up : those emails (which you prefer to believe were 'leaked' - why is that ?) have turned into fool's gold for the so-called skeptics. However, like a dog gnawing away at it's manky bone, some people just cannot seem to let go. I still think it's down to embarrassment, mainly - embarrassment that the so-called skeptics, who were led to believe that the emails proved AGW to be a scam and a conspiracy, have now realised they were had by their very own trusted blog gurus. -
Ken Lambert at 23:04 PM on 25 July 2010The nature of authority
DougB #106,107, Adelady #108, kdkd #109 I was happy to leave 'Climategate', but DougB wanted to kick along. Corcoran summarises the story pretty well here: Quote: "The emails portray embattled scientists fighting desperately to interfere with official FOI processes. One now widely-circulated email, by Mr. Jones, asked Mr. Mann: “Can you delete any emails you may have had with Keith re AR4? Keith [Briffa] will do likewise. He’s not in at the moment — minor family crisis. Can you also email Gene and get him to do the same? I don’t have his new email address. We will be getting Caspar to do likewise.” In this email, Mr. Jones is asking key scientists who worked on AR4 — the 4th Assessment Report on the science of climate change produced by the IPCC in 2007 —to erase all emails related to that report." endquote One might ask why these emails needed to be erased if those involved felt they were just a bit of honest disagreement between professionals acting in good faith. Clearly they felt there was something to hide if subject emails were revealed in FOI requests. As for legality or illegality m'lady, destroying material to avoid an FOI disclosure might indeed be illegal too. These days whisteblowers are being encouraged and protected in many jurisdictions so that malfeasance is exposed. No doubt the information or documents thus revealed are regarded as theft or breach of confidentiality by those exposed by whistleblowers. I was more interested in the attention drawn to Dr Trenberth's paper and subsequent discussions - even something on the wide error bars on cloud and aerosol forcings. -
James Frank at 22:47 PM on 25 July 2010Rebutting skeptic arguments in a single tweet
I'm not sure Orwell would be as upset as you seem to think. You see, your post was right beside Orwell's blog in my Google Reader today. I found that kind of funny when you kept mentioning him. -
Ned at 21:58 PM on 25 July 2010Rebutting skeptic arguments in a single line
RSVP, if you made claims like "one plus one equals two" I suspect no one would ask for a reference. Instead, your claims are basically (a) waste heat is somehow very important and needs to be talked about constantly, despite being a microscopic fraction of the energy provided by CO2-induced radiative forcing; and (b) a century's worth of laboratory measurements of CO2 are incorrect. As Carl Sagan said, extraordinary claims require extraordinary evidence. -
RSVP at 21:12 PM on 25 July 2010Rebutting skeptic arguments in a single line
To Ari, "Browsing your comments in this thread for example shows that you have made several claims and arguments but you haven't offered any references to peer-reviewed science. " My "claims and arguments" stand on their own, or is one now expected (for instance) to back claims that one plus one equals two? -
kdkd at 17:57 PM on 25 July 2010The nature of authority
Ken #105 You must be short of substantive argument if you're trying to recycle this old discredited material. None of the climate conrarians attempts to claim nefarious activity within the CRU and their collaborators has met with much success. The enquiries have pretty much universally found that the allegations made by contrarians were without substance. You can of course recycle some more conspiracy theory claiming an inside job put-up, but this will discredit your argument even more :). -
Ari Jokimäki at 17:31 PM on 25 July 2010Rebutting skeptic arguments in a single line
RSVP, #75: The introduction text to my paperlist you quoted is outdated, as several of the papers now have full text available. Also, it is always possible for interested person to purchase the full texts of the papers. I have updated the introduction paragraph to reflect these things. In my experience, most of the "AGW counter arguments" are not even accompanied by abstracts on any peer-reviewed papers. Browsing your comments in this thread for example shows that you have made several claims and arguments but you haven't offered any references to peer-reviewed science. -
adelady at 17:17 PM on 25 July 2010The nature of authority
At least Ken had the decency to put the word 'leakers' in quotes. I'm not much fussed whether it was an inside job or not. Theft is theft, illegal is illegal. I tend to use the prism of theft v. leak to make an initial assessment. If someone uses the word 'leak' rather than theft, I'm unsurprised to find that the following text contains a fair amount of silliness. -
Doug Bostrom at 15:51 PM on 25 July 2010The nature of authority
By the way, Ken, every time a "skeptic" brings up the ancient, dusty emails it's essentially an admission that such a "skeptic" does not have anything useful to say about the actual science under discussion. Gossip is not science. -
Doug Bostrom at 15:41 PM on 25 July 2010What do you get when you put 100 climate scientists in a room?
GC, you don't appear to even be aware of what was being decided in the court case you yourself brought up. You've not even yet acknowledged that your original assertion that the judge found "dishonesty" on Al Gore's part was completely unfounded. Why on earth would anybody then take your advice to fill their heads with Monckton's silly twaddle? -
gallopingcamel at 15:36 PM on 25 July 2010What do you get when you put 100 climate scientists in a room?
JMurphy (#123), Al Gore was shown to be "in error" by a British high court on 11 issues mentioned in his book. My personal favourite stems from Al's claim that Ice Age temperature cycles were driven by CO2 when the data shows the exact opposite. In your post (#121) you mentioned Monckton. My first impression of the viscount was "another upper class British nincompoop with a plum in his mouth" but even so, he makes more sense than Al Gore does. While I doubt that you will take the time to read the link below, I am hoping that others will: http://scienceandpublicpolicy.org/monckton/goreerrors.html -
Doug Bostrom at 15:36 PM on 25 July 2010The nature of authority
Bottom line, Ken: Whatever person or group appropriated and published the emails thought it best we not see all of them. It's a familiar odor, no more honest than attempting to break into RealClimate's server to exploit it as a publication site, the perpetrator's first choice for dissemination. All the hallmarks of a juvenile political stunt, but unfortunately slipping into the minds of a receptive and credulous audience not known for critical thinking skills, hence the gullible acceptance of a careful set of selected quotes as a "coherent narrative." Your assertion that the victims of the perpetrators should defend themselves by publishing the material redacted by the perpetrators is frankly bizarre. -
Ken Lambert at 15:12 PM on 25 July 2010The nature of authority
DougB #91 I agree that the 'leakers' of the Climategate emails had an agenda - either a closet skeptic(s) or a disgruntled insider assembled the files of emails. Corcoran says he read all the first 5 years and they form a coherent narrative. He says the more recent emails are obviously hurriedly assembled and difficult to follow. Corcoran acknowledges that they were deliberately released prior to Copenhagen for maximum effect. The critical issue is their authenticity - and that has not been challenged by the scientists involved. The emails revealed however that certain scientists were themselves planning a blitz: quote: "The last emails were sent between Nov. 10 and 12 this year (2009), five days before the whole cache was stolen. One of those last emails outlines an attempt to orchestrate a media blitz by scientists at the American Geophysical Union annual meeting. The strategy was aimed at shaping public opinion going into the Copenhagen talks that ended yesterday." endquote Maybe they were simply 'outblitzed'. Doug your argument tries hard to dismiss the emails as a 'selective dataset'. This is a strawman. They never constituted a 'dataset'. They are a valuable record of the behind the scenes discussion and modus operandi of key players in the AGW story. You also have to consider the difficulty of the leakers slanting the narrative by selectively quoting emails and leaving out others. The narrative for the first 5 years according to Corcoran is coherent - so leaving out vital 'AGW friendly' emails would tend to destroy the narrative, which those involved agree, are the scientists own words. If there are emails missing which would significantly change the story - the scientists involved should have released them in their own defence. If they have - point me to them. I think the shock to everybody with an interest in climate science, was the attempt to present to the world a front of robust high quality research; when in fact there was significant internal dissent, unprofessional personality clashes and far greater uncertainty hidden in the private communications. -
shawnhet at 14:51 PM on 25 July 2010The nature of authority
johnd:"shawnhet at 04:31 AM, it applies as the overall NETT effect over longer time frames. As skywatcher makes mention of, depending on the seasons, types of clouds and regional conditions, the shorter term effects are much more complex and variable with the opposite occurring. It is the balancing out of all these factors that determines to NETT effect which is what is relevant in climate time frames." At the risk of repeating myself here, *if* higher temps lead to more WV in the air which in turn leads to more cloudiness and a reduction in temps, then there are only two ways I can think of for the observed inverse relationship btw cloudiness and temps to hold. Either this relationship is masked by some sort of natural variation OR the temperature feedback from increased cloudiness is so strong as to completely cancel out the original temperature rise. Personally, I don't think the latter possibility is at all likely. Perhaps an example will suffice help here: Imagine a world with no natural cloud variation, such that a 1C initial warming causes an increase in cloudiness of x% which reduces the temps by 0.5C in that circumstance, the relationship btw cloudiness and temps will be direct, right? Now assume that over top of that we add a natural decrease in cloudiness of -2x%, the temps will increase and the cloudiness will decrease, but they will not decrease *because* of the temp increase, but rather in spite of it. I don't disagree that seasons can make things more complicated. KR, I don't disagree that the observed relationship btw cloudiness and temps over recent history appears to be inverse. My point is whether this relationship should necessarily be consistent. chris:"”Thus it is reasonable to expect that as atmospheric water vapour content varies, so too would that of clouds.” No that’s not a “reasonable” expectation. The fact that a warming atmosphere (so far) tends to maintain a near constant relative humidity means that cloud cover doesn’t necessarily vary with water vapour content. A warmer atmosphere maintains a higher water vapour content than a cooler one, and there is no reason to expect the extent of cloud cover to vary with temperature." Well, I suppose it depends on your definition of reasonable here ;), but clearly temperatures a couple of kilometers above the Earth's surface aren't "maintained" - rather they are always heating or cooling. Assuming constant RH, cooling of 1C will condense more water from warmer air than cooler air. Since condensing vapor is one of the chief components of cloudiness, I agree with the idea that *everything else being equal* increased temps should increase cloudiness. Cheer, :) -
ScaredAmoeba at 14:31 PM on 25 July 2010Rebutting skeptic arguments in a single tweet
John, as ProfMandia said. Plus a big thank-you to Kieren Diment. -
chris1204 at 11:09 AM on 25 July 2010Assessing global surface temperature reconstructions
PS: Thanks Ned for the G&T :-) -
chris1204 at 11:09 AM on 25 July 2010Assessing global surface temperature reconstructions
dolormin @ 29: Actually, the Mosher reconstruction originally appeared on WUWT where he makes a review similar to Ned's of other data sets. He concludes: 'As noted above there are many questions about the calculation of a global temperature index. However, some of those questions can be fairly answered and have been fairly answered by a variety of experienced citizen researchers from all sides of the debate. The approaches used by GISS and CRU and NCDC do not bias the result in any way that would erase the warming we have seen since 1880. To be sure there are minor differences that depend upon the exact choices one makes, choices of ocean data sets, land data sets, rules for including stations, rules for gridding, area weighting approaches, but all of these differences are minor when compared to the warming we see. That suggests a turn in the discussion to the matters which have not been as thoroughly investigated by independent citizen researchers on all sides: A turn to the question of data adjustments and a turn to the question of metadata accuracy and finally a turn to the question about UHI. Now, however, the community on all sides of the debate has a set of tools to address these questions.' I guess it illustrates the reality that reasonable stuff does appear sometimes on WUWT. dhogaza @ 28: I haven't had a chance to check out WUWT on his CHC/halogenated compound gaffe. Although I happen to remember enough chemistry to know that CFCs are precisely that (at least when you say it explicitly), I probably wouldn't have remembered the Montreal Protocol. It's the sort of mistake I could easily have made. There's a saying which I'm sure has been called somebody or other's law: Before conspiracy, suspect stuff up. It's really a variant of Occam's razor (not an infallible instrument but often useful). At any rate, what is very interesting is the movement towards the middle ground on the part of a number of 'sceptical' players. -
ProfMandia at 09:59 AM on 25 July 2010The nature of authority
Graham, This is an excellent piece. I will be forwarding to many. -
EOttawa at 09:55 AM on 25 July 2010Rebutting skeptic arguments in a single tweet
So is the penguin going to get a cape? :) -
ProfMandia at 09:49 AM on 25 July 2010Rebutting skeptic arguments in a single tweet
John, You continue to be cutting edge with regard to communicating the science. You are a hero to many of us. Thank you. -
chris at 09:32 AM on 25 July 2010The nature of authority
johnd at 08:55 AM on 25 July, 2010 "If CO2 levels remained apparently constant from the ice age until the industrial revolution, how could the inter-glacial warming occur if CO2 works the way it is postulated?" It's not obvious what you mean by that johnd. Can you expand on your point or reframe it? After all CO2 levels clearly didn't remain "apparently constant from the ice age until the industrial revolution". The pre-Holocene "ice age" [CO2] was around 180 ppm, and the pre-industrial [CO2] was around 270 ppm. Did you mean something else?? -
mothincarnate at 09:21 AM on 25 July 2010Rebutting skeptic arguments in a single tweet
Awesome John. We need more short punchy replies to denial (I do bits and pieces, but obviously not to the same quality). We waste a lot of energy have circular debate with those who reject the science when we should be able to deflect this kind of thing to standard places and begin the more interesting discussions of what to do from here! :) -
chris at 09:17 AM on 25 July 2010The nature of authority
johnd at 04:21 AM on 24 July, 2010 ”…clouds have been determined as having an overall nett cooling effect…” One needs to be careful. As Palle et al (2006) have described an albedo change due to secular cloud variation doesn't necessarily imply a surface temperature response since clouds have warming ("heat trapping") as well as cooling (albedo) effects. Palle have more recently (Palle et al., 2009) described the total albedo variation (expected to be mostly cloud-related) and found that this has been pretty trendless during the last 10 years. E. Pallé et al (2006) Can Earth's Albedo and Surface Temperatures Increase Together? Eos Trans. AGU, 87(4), doi:10.1029/2006EO040002 link to paper Palle et al. (2009) Inter-annual variations in Earth's reflectance, 1999-2007 J. Geophys. Res. 114, D00D03 link to abstract ”But there is still that indecision as to whether temperature is a function of clouds or clouds a function of temperature. We may find that there is rather little relationship between Earth temperature and cloud cover, largely due to the fact that a warmer atmosphere maintains a higher concentration of water vapour ( KR has described this), and so cloud cover has no necessary systematic relationship with temperature. After all the Earth has warmed by an amount (0.8-0.9 oC) since the middle of the 19th century, that supports the conclusion that the climate sensitivity cannot really be below 2.0 oC (i.e. the temperature rise is that expected even without factoring in the slow response times of the climate system and the cooling effects of atmospheric aerosols, although one should consider non-CO2 contributions like nitrous oxides, methane and black carbon). So there pretty much has to be a positive feedback from water vapour as predicted by our knowledge of the greenhouse effect. Otherwise one might ask: “where is this supposed cooling effect of clouds”?! So far (as far as I’m aware) there is only one direct analysis of the cloud response to warming surface temperatures. This study (Clement et al., 2009) tends to support the conclusion that the cloud feedback is a positive one (i.e. a warmer equatorial sea surface results in a reduced cloud cover). However more data is needed on this. A. C. Clement et al. (2009) Observational and Model Evidence for Positive Low-Level Cloud Feedback Science 325, 460 – 464 link to abstract Likewise many of the determinations of climate sensitivity (Earth equilibrium surface temperature response to increased greenhouse gas concentrations) are phenomenological, in that they assess the relationship between CO2 and surface temperature during ice age transitions or during the deep past. In these analyses all of the feedbacks (whether positive or negative) are “lumped in”. Since these analyses pretty uniformly find a climate sensitivity near 3 oC, it’s difficult to support a significant negative cloud feedback (unless there is a positive feedback we’ve not yet discovered). R. Knutti and G. C. Hegerl (2008) The equilibrium sensitivity of the Earth's temperature to radiation changes Nature Geoscience 1, 735-743 link to paper johnd at 09:26 AM on 24 July, 2010 ”Thus it is reasonable to expect that as atmospheric water vapour content varies, so too would that of clouds.” No that’s not a “reasonable” expectation. The fact that a warming atmosphere (so far) tends to maintain a near constant relative humidity means that cloud cover doesn’t necessarily vary with water vapour content. A warmer atmosphere maintains a higher water vapour content than a cooler one, and there is no reason to expect the extent of cloud cover to vary with temperature. That’s not to say that there may not be more rainfall in a warming world (Allen et al. 2008). But remember that rain clouds are just a proportion of total clouds. We expect in a warming world that rainfall will decrease in the equatorial regions of the Earth (consistent with Clement et al’s observation of reduced cloud cover above warming sea surface) and we will have increased rainfall at higher latitudes. That’s pretty much what is observed (Zhang et al, 2007). Thus during the 20th century, the latitude band from around the equator to around 30 oN has become drier (reduced rainfall; enhanced drought) as the Earth has warmed during the 20th century, much as predicted. This latitudinal band of reduced precipitation will widen as the Earth continues to warm (and so, for example, Amazonia is expected to dry progressively towards the South as the Earth continues to warm). The higher latitudes (especially above 50o N and below 10 o) have seen enhanced precipitation. Global warming and shifts in precipitation regimes is expected (and already observed) to lead to amplification of extreme precipitation events (e.g. Allen et al. 2008). X. Zhang et al. (2007) Detection of human influence on twentieth-century precipitation trends Nature 448, 461-465 link to abstract RP Allen et al. (2008) Atmospheric warming and the amplification of precipitation extremes Science 321, 1481-1484 link to abstract -
Doug Bostrom at 09:13 AM on 25 July 2010The nature of authority
JohnD regarding the paltry record for longitudinal cloud data there may be some hope for improvement at seeing into the past. Though they're presently focused on sea ice there's a group working on reprocessing Nimbus satellite data providing nearly continuous twice-daily coverage capable of reasonable cloud imagery from approximately 1964 to 1972 See this site. Also with regard to the behaviors and role of clouds I still encourage taking a look at the leads to a Science paper I mentioned upthread looking at their non-obvious properties. -
johnd at 08:55 AM on 25 July 2010The nature of authority
scaddenp at 06:42 AM , I think generally data is collected first and published papers come somewhat afterwards. It must be appreciated that the ISCCP research is very much a work in progress, and that our understanding of how the climate works will advance beyond whatever the latest IPCC report contains. The whole subject of clouds is acknowledged as being the least understood of all the factors driving climate by scientists on both sides of the debate, and it would be a brave person who claims that they know better than that. Thus the door has been left open to the possibility that advances may place a different perspective on current understanding, and that is what I find interesting and worthy of discussion. I really don't subscribe to the notion that all that there is to know is already known, in any field, or that we should reinforce that notion by endlessly patting ourselves and each other on the back, and rejecting anything that might challenge such a comfortable enjoyable existence. The correlating of clouds and global temperatures is only one, perhaps small part. The most important part, at least I think so, is getting a fuller understanding of all the factors that are involved in the formation of clouds. The difficulty for understanding clouds is that there is very limited amount of what could be described as high quality data, and that available is only for a very limited time span, a couple of decades. It also appears impossible to reconstruct proxy historical data. It therefore puzzles me how clouds have been adequately accommodated in climate models as the assumptions cannot be validated by back-casting, given that they are a significant factor in determining the energy balance. With regards to the ice age question, firstly it needs to be appreciated that even during the ice ages, the planet was not one solid block of ice. It still had the tropical regions with the accompanying temperature differentials, resulting wind circulations and varying ocean currents, and clouds I presume. The types of clouds present would have to be considered, but it still comes down to knowing what are all the factors involved in the formation of clouds. An equivalent question could be asked about CO2. If CO2 levels remained apparently constant from the ice age until the industrial revolution, how could the inter-glacial warming occur if CO2 works the way it is postulated? -
Doug Bostrom at 08:36 AM on 25 July 2010Part One: How do ice sheets lose ice?
"Agwscam" what we know is that regardless of what else may be happening with the climate the modifications we're making to the atmosphere will impose their own warming, added to whatever else is going on. It's worth noting also that so far there's no known natural variability in play just now to explain the long term trend in climate we're seeing while on the other hand the changes are a reasonable fit to predictions arising from our understanding of physics and how the climate functions. Think of it this way: starting with a balance of $0 you deposit $10 in your bank account and when you check your balance you see $15 available. Your $10 is there and some unknown (rich uncle? bank error?) has gifted you with $5. The $10 you expected to find is present, leaving a separate puzzle to be solved. By the way, did you know your chosen handle here violates the comments policy and thus technically speaking all of your remarks should be deleted? Give a thought to changing it or resign yourself to possible frustration with having your comments reliably appear in public on this site. -
dhogaza at 07:37 AM on 25 July 2010What do you get when you put 100 climate scientists in a room?
To answer your question, agwscam, we'd have to know what an "organization with a pro-AGW theory position" is. Can you give some examples?
It's a slur ... the write is George Monbiot. In our modern up-is-down world, if you accept the conclusions of science, you are a "moonbat", unless you're "fat" (that's for gallopingcamel, I don't understand why he hasn't brought up the most important fact that proves climate science wrong). -
KR at 07:17 AM on 25 July 2010The nature of authority
shawnhet - the long term inverse relationship of global cloud cover to temperature is something shown by johnd's 1983-2008 data here as compared to the temperature data over that period. Some additional information comes from the Warren paper I referred to earlier, showing no trend in coverage from 1952-1981, when the temperature wasn't showing much of a trend either. This doesn't prove the relationship, but does demonstrate that over that 29yr period global cloud coverage didn't appear to change independently of global temperature. Looks like a clear inverse relationship - I will freely admit to not having any solid theories why. I could always make some wild guesses, though... :) -
ptbrown31 at 07:14 AM on 25 July 2010It's Pacific Decadal Oscillation
Tom Dayton - Here is the WHOLE actual definition: "Updated standardized values for the PDO index, derived as the leading PC of monthly SST anomalies in the North Pacific Ocean, poleward of 20N. The monthly mean global average SST anomalies are removed to separate this pattern of variability from any 'global warming' signal that may be present in the data." If the "global warming" signal wasn't subtracted out of the index there would be an upward trend. -
scaddenp at 06:42 AM on 25 July 2010The nature of authority
johnd - I struggled to find adequate metadata or published papers that illuminate your ISCCP data set. I asked at realclimate and got this response from Gavin Schmidt. "First impressions are that this has a number of artifacts in it likely due to inhomogeneities in the satellites (varying levels of spatial coverage through time as satellites drop in or out). The definitive precipitable water vapour analyses are discussed in Chapter 3 of AR4, and I'd start with those publications and authors to see what the differences are with the ISCCP product". And indeed a very different picture is shown there. There is a danger here again of amateur analysis drawing a long bow from data that is improperly understood and not fit for purpose. Before you get carried on cloud reducing sensitivity, please consider how the ice-age cycle could happen if clouds worked the way you postulate. -
AWoL at 06:34 AM on 25 July 2010What do you get when you put 100 climate scientists in a room?
I keep on hearing an AGW proponent referred to as "George Moonbat". Can anyone confirm that such a person exists? I must say it is an unusual name, and I wonder if it is a nickname rather than a real name. Thanks in advance. -
johnd at 06:33 AM on 25 July 2010Models are unreliable
JMurphy at 02:56 AM , I think it is quite clear that I was referring to "long term weather forecasting capabilities". It is not so much about insufficient localised information, but about forecasts that are so vague that they are meaningless (a 50% chance of above average rains and a 50% chance of below average rains is a common forecast) and despite the vagueness they still have a poor strike rate. In contrast, private forecasters are able to demonstrate an overall much higher degree of accuracy plus provide detailed local information to satisfy their customers requirements. In the meantime as long as the government injects sufficient funds to upgrade to super computers, we still have to wait perhaps 3 to 7 years before we get forecasts that are "good enough to be useful". -
agwscam at 06:19 AM on 25 July 2010Part One: How do ice sheets lose ice?
Even if one were to concede your theory it brings to mind two questions; How do you KNOW that this isn't all a perfectly normal progression of a natural gradual warming climate cycle when you have no satellite data to compare it to because all of this satellite data is brand new (this information would be impossible to reconstruct)? Even if you were somehow able to prove the point above, how do you KNOW that you can definitively exclude other causes and that anthropogenic CO2/GHG is to blame?
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