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scaddenp at 08:43 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric, until a new paper with new data and/or methods can show an improvement on Royer, I dont see how its possible to stick with Veizer interpretation. Reality is not a matter of opinion. If Veizer thinks Royer wrong, then there has been ample time for a response. A conversation, interpreted and reported by a well-known denier, is hardly evidence. -
michael sweet at 08:26 AM on 11 June 2011Ocean acidification: Some Winners, Many Losers
John, I have seen reefs that have degraded and slime is the correct discription. It is usually blue green algae or red slime algae. Sometimes it is hair algae, which is also slimy. If you have citations that the replacement algae is seeweed and not slime you need to present them, not assert without any evidence that seeweed is the replacement algae. Suggesting that "a few misguided coral reef scientists subjectively refer to "slime" on reefs," without citations is not a scientific argument, it is unsupported opinion. -
Tom Curtis at 08:10 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric the Red @59 & 62: First, your second paper is Shaviz and Veizer, 2003. It still pre-dates Royer et al, 2004; and is refuted by it. Second, below is the crucial image from Came et al, 2007, of which Veizer was one of the co-authors. It compares the two temperature records from that paper with to previous reconstructions of Phanerozoic temperatures, that by Veizer et al, 2000 (light grey) and that by by the GEOCARBIII model (as shown in the second image in my 51). Also shown along the bottom is Scotese's division of the global climate into warm and cool periods. I have added a green line for easy alignment.
It is very clear from this that Came et al, 2007 tends to confirm Royer et al's conclusions, and to disconfirm those of Veizer et al, 2000, and Shaviz and Veizer, 2003.
Having said that, Came et al examine samples from just one location and one formation from the Silurian. The GEOCARBIII model has a resolution of 10 million year, and as the recent record of glacials and interglacials shows, temperatures can fluctuate a lot in such a short period. Therefore Came et al is neither a definitive confirmation of Royer et al, nor a definitive refutation of Veizer et al. Came et al in fact take refuge in that fact to say,
"Our re-interpretation of the d18O values of Silurian and Pennsylvanian carbonate fossils also may apply to other parts of the Palaeozoic. However, there remain several marked discrepancies between climate reconstructions using the GEOCARB model versus those implied by the Scotese geological record and the Veizer et al. oxygen isotope record (which generally agree with each other, at least in timing of climate variations), and it is difficult to imagine that all time periods will be resolved in the same way as those examined in this study."
So, Veizer does not think that Royer is right; but subsequent evidence which he has contributed has tended to confirm Royer's conclusions and disconfirm Veizer's. Disappointingly, Came et al do not discuss ocean pH even once. Considering the nature of Royer et al's critique of Veizer et al, that is a glaring oversight. -
chris at 07:10 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
whoops...in my second paragraph I should say: "..and so a significant change in temperature is expected to lead to a change in climate" -
skywatcher at 07:09 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
#6 Your estimate may be too high, depending on both the proportion of methan e to CO2 in the carbon released, and also the shorter lifetime of methane in the atmosphere - ~12 years as opposed to hundreds of years for CO2. But I don't know the physics enough to be sure. The basic idea of extra greenhouse gases being released due to warming of the Arctic does not make happy reading however you slice it though. -
chris at 07:07 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Badgersouth at 06:22 AM on 11 June, 2011 Yes, OK; I think we have to recognise that words are shorthands for things, and that we sometimes need some informed knowledge about the meaning of a particular word or phrase in a specific context. That's a fundamental element of language - it would be cumbersome to communicate with each other if we didn't have shorthands to encapsulate more complex concepts! So yes "climate sensitivity " is a shorthand for something like "equilibrium response of the globally averaged near Earth surface temperature to a forcing equivalent to a doubling of atmospheric [CO2]". It doesn't really refer specifically to "climate" at all! However climate (which is a local property as you point out) is intimately related to the Earth's globally averaged surface temperature, and so a significant change in temperature is expected to lead to a change in temperature. So there is a connection. Obviously "climate" isn't amenable to definition with a single quantitative metric, as temperature is. So in order to usefully interpret "climate sensitivity" we need some information on the manner in which excess energy in the climate system in response to a forcing is spatially-distributed, and its consequences (on the hydrological cycles, weather systems, land ice and plant responses etc.), to assess the likely true climate responses to a change in globally averaged temperature... -
Albatross at 06:43 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric @62, "Many people have told me that I am "in denial" recently to entertain the thought that climate sensitivity could be closer to 2 than 3." That would be completely at odds with what Christy and Lindzen believe. Also, keep in mind that on our current path we are easily going to double CO2 levels, and may quite easily treble them. So we are very likely looking at well over 2 C warming in an incredibly short time in geological terms, and that at a time when we will likely have over 10 billion mouths to feed. -
John Hartz at 06:33 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
I suggest that every article in the Christy Crock series have a tab listing the titles of the other articles in the series with a link to each embedded in the title. -
John Hartz at 06:26 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
If Dr. James Hansen were not concerned about the negative consequences of climate change in the 21st century, he would not have written "Storms of My Grandchildren." -
John Hartz at 06:22 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
@Chris #65: Those are all good points and thank you for posting them. My frustration really stems from what I perceive to be an inconsistent use of the term "climate" among scientists. In the above discussion, the term really means "the temperature of the lower atmosphere as measured by a single metric." (Even that single metric masks all kinds of significant spatial and temporal variations within the lower atmospher during the course of a year.) If the basic definition of the Earth's "climate system" includes the atmosphere, the hydrosphere, the cyrosphere, etc., the word "climate" should not then be used to define one subcomponent of that system. -
dhogaza at 06:16 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
Garethman - obviously you don't understand post #16 and the inline addendum by DB. -
Bob Lacatena at 06:13 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric, Forgive me, but your position seems to be based entirely on a convenient form of cherry pick, but instead of cherry picking the data, you're cherry picking the one paper you want to use on which to base the all of the weight of your opinion. There are various and sundry studies, almost all pointing to high(er) climate sensitivity. You have picked one study, from 10 years ago, which is contradicted by a number of other studies, as well as the author himself, and you choose to put huge emphasis and weight on that one paper, to the point of declaring that "I disagree that the sensitivity has never been less than 2.5 or been as high as 5." Your defense of the paper comes from a blog post by someone who claims to have spoken to the author of the original and contravening studies, with hints of partisan politics pressuring him into "compromising" on the studies wording and conclusions. Is this really the skeptical approach to the science? -
chris at 05:58 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Badgersouth at 05:20 AM on 11 June, 2011 There are (at least) three reasons why the Earth surface temperature is a useful and important metric. 1. Averaged over several years [i.e. averaging the effects of seasonal variation and short term ocean surface variability (El Nino/La Nina)] the Earth's surface temperature seems to remain relatively steady in the absence of external forcing. So the averaged Earth surface temperature seems to be a decent metric for the amount of energy in the climate system, despite the various energy fluxes through the system. And so the change in the Earth surface temperature is a good metric for the change in the energy in the climate system in response to a forcing (e.g. from enhanced greenhouse forcing in response to a change in [CO2] or changes in solar output). 2. From a terrestrial perspective the Earth surface is the location of the biosphere, and that's of fundamental interest to us. The Earth surface temperature is probably the most important metric for assessing potential effects of forcings on the biosphere. 3. Partly due to 2 [the response of elements of the geosphere and biosphere to temperature changes (plant leaf stomatal responses; isotopic composition of shells, wood and ice; the spectrum of species that thrive at a particular temperature, and so on), temperature changes leave a variety of signatures in the paleo-record that allow localized surface temperatures to be reconstructed. So this metric provides a means of assessing the relationship between changes in paleo[CO2] (which also leaves a variety of signatures in the paleo-record) and temperature (aka climate sensitivity), which informs us of contemporary and future temperature changes in response to massively enhancing the Earth's greenhouse effect... -
Albatross at 05:50 AM on 11 June 2011There's no room for a climate of denial
Eric and Norman, Which characters are you in the video that I posted @28? Extreme weather events (e.g., droughts, heavy rainfall, heat waves) are on the increase, that much is objectively and quantitatively described in the reputable scientific literature. And events in the past 12 months or so are consistent with the the long-term trends documented in the literature. Anyway, thanks for continuing to provide such an excellent example of denial at work. You will disagree I'm sure, but your failure to recognize the err of your arguments and only further enforces the OP's point. Norman, "Albatross, this thread is asking why so many doubt AGW's dire predictions" Your opinion is not shared by those in the know an by climate scientists. If anything it is shared by misguided, or misinformed or conspiracy theorists. Also, you are arguing a strawman, the OP says: "However, refusing to accept the overwhelming scientific evidence is not scepticism but denial." and this "Paradoxically, as scientific evidence for human-caused climate change pours in, interest and belief in climate change within the public is on the decline." That is essentially what the OP is about, not the red herring what you are trying to push above. -
Dikran Marsupial at 05:28 AM on 11 June 2011There's no room for a climate of denial
Eric the Red wrote: "Maybe, but how many natural disasters can you name from 1998?" hardly any Eric, I think you will find that is very much the point Tom was making. -
John Hartz at 05:20 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Perhaps these are "dumb" questions, but nontheless... Because the enhanced greenhouse effect is all about the transfer of heat both within and between the various components of the Earth's climate system, why is only one metric, i.e., annual average mean global temperature of the troposphere" being used to define "Climate Sensitivity"? Doesn't this single metric mask all kinds of other things that are happening within and between the other components of the climate system? -
chris at 05:19 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric the Red at 04:36 AM on 11 June, 2011 Really Eric? Veizer publishes a paper in Nature with a reinterpretation of his original sea surface temperature data, that negates the possibility that the tentative Shaviv/Veizer hypothesis could be correct when considered through the Paleozoic period...... ....and now we're supposed to believe what someone says on a blog about a conversation he had with Veizer that the latter doesn't actually believe the stuff he published in the Nature paper. No thanks Eric...I'm sticking to the science. Science is about evidence and the evidence simply doesn't support the tentative hypothesis of Veizer and Shaviv. Veizer's own data pretty much scuppers it. "do not be swayed by misinformation". Brilliant Eric! In your eyes Veizer's own work constitutes both the information and the misinformation on this topic. Truly anything and everything can be twisted into a misrepresenters "argument"! -
garethman at 05:19 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
Albatross A new study out documenting the loss of snow pack in the northern Rockies......... Over the past millennium, late-20th-century snowpack reductions are almost unprecedented in magnitude across the northern Rocky Mountains, and in their north-south synchrony across the cordillera. Both the snowpack declines and their synchrony result from unparalleled springtime warming due to positive reinforcement of the anthropogenic warming by decadal variability. Garethman Thanks for that, looks interesting, unfortunately it is behind a paywall so I could not look at the article. If you have read it I would be interested in the tree rings. Were these aged in terms of Millennia in being used to compare with contemporary tree rings, in other words, were these trees a thousand years old? or were the current tree rings compared to snowfall data from other sources?Response:[DB] Try here.
Poking under rocks sometimes yields useful results. ;)
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garethman at 05:12 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
Hi Dhogaza, I think your more detailed chart shows essentially the same thing? You are correct in that the loss of sea ice has remained constant, but logically, if it has stabilised at a lower level that goes without saying? Though as I have previously mentioned I strongly suspect the reduction will again start in the near future. I happy to be proved wrong by the way! I’m not sure what the “nice try" refers to? Rugby perhaps? Are we in a competition? I also personally don’t think these charts are “lame”, they are all useful. Some focus in some areas, some in others. But to get the overall picture it’s important to look at as many as possible and not ignore those you don’t like, which is why I appreciate seeing yours or any other useful indicators you may be so kind as to direct me to. -
Eric the Red at 04:56 AM on 11 June 2011There's no room for a climate of denial
Fair enough. However, one year does not a trend make. http://www.ncdc.noaa.gov/img/climate/research/tornado/tornadotrend.jpg Yes, this year has been unusual. As of Jun 1, we have witnessed 75 violent tornadoes (EF3 or greater), that is the third highest since 1950. With the rest of the summer remaining, we will very likely pass 1965 inot the number 2 spot, but may not break 1974's total. Was 1974 an unusual year? Apparently, we witnessed a similar La Nina occurance that year. If we finish near or above 1974, I would still say it has been an unusual year, but not rare. It has also been very cold and snowy winter, but does that mean we are headed for colder temperatures in the future? -
garethman at 04:46 AM on 11 June 2011Geologists and climate change denial
Chill out folks! I’m not casting doubt on climate change, though for some reason this is continually read into my posts. I am interested in the human reactions to the science, the depth and breadth of emotion. It’s a painful subject for some, but fascinating all the same. Incidentally anyone who does not believe young people have more radical ideas than older people and say things they later takes a differing view on are probably in denial with regard to human behaviour and should probably go and visit a University campus to see such dynamics in action. http://www.climatecamp.org.uk/ The same with climate camp. I have camped in the same field with these guys for weeks at a time. They are enthusiastic and radical, but objective? maybe not, but it’s reassuring to see young people still have heart and are motivated to try and change the world for the better. They will be at Glastonbury again this year, if you are lucky enough to get a ticket, go and visit them, I’m sure they would rustle up a cup of tea and inspire you. What I do wonder judging by reactions to my posts is whether a lot of the odd anger expressed at posters who give contrary views or those who question evidence is misdirected. A common feature of human behaviour is that people will express anger at a subject unrelated to the cause of their anger, because it is unacceptable to express anger at the real thing. I see Right wing individuals railing at everything from immigration to climate change, when on an individual basis they are probably upset at their lack of success in life, or their family dynamics. Whenever you see an "over the top” reaction to an innocuous situation or post you can be fairly sure that it is anger expressed in an inappropriate direction. I think it’s also a mistake to call belief in science “blind faith” I have not seen any sign on this site that supports such an idea, or indeed that evidence is suppressed, and lets face it, the evidence for a warming climate is pretty conclusive. So it’s not blind faith, it’s not a religion, but our beliefs in the science and what we do about is are very much coloured by who we are. Perhaps the profession of forensic mental health are another group who are just an awkward bunch when it comes to climate change? -
Eric the Red at 04:36 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
For those who think that Veizer has changed his position, you might want to read this: http://jennifermarohasy.com/blog/2007/09/new-nature-paper-jan-veizer-contradicts-his-own-results/ More recent statements by Veizer seems to show that he is standing by his original conclusions, and the merits of his original paper. Do not be swayed by misinformation. Actually, I do not see where I have been shown to be wrong, although I am open-minded enough to look back. Many people have told me that I am "in denial" recently to entertain the thought that climate sensitivity could be closer to 2 than 3. That number is not unreasonable, and does not contradict the science. It does not fall beyond any reported likely range, and in some cases is the most likely value. I have seen people applaud those who state that the climate sensitivity is 6 or above, yet that is above most likely ranges. -
dhogaza at 04:22 AM on 11 June 2011There's no room for a climate of denial
"Maybe, but how many natural disasters can you name from 1998? That is only 13 years ago, and occurrances do not come to my mind rapidly. Yes, I can remember the earthquakes from the past few years, the tsunami in Indonesia, and hurricane Katrina. However, before that, everything becomes a little bit fuzzier." Then one has to do actual research before dismissing this year as being not unusual, and to dismiss it in such a way *without* doing such research is simply denialism. Especially when scientists are telling us that this was by far the most extreme tornado April in history, that we're seeing 100 year floods, etc etc etc. There have been a large number of extremely rare events in the last year, and basic probability theory tells us that the combination of a large number of low-probability events has a far lower probability. So unless you can point to evidence that these events aren't actually rare (Joplin isn't the point, it's the incredible level of tornado activity of which Joplin and Tuscaloosa were part of that's the point, so "one tornado in 1954" is not a relevant comparison), I at least will run with the fact that the combination of low-probability events we're seeing is extraordinarily improbable, and very possibly unique in recorded history. -
Eric the Red at 04:16 AM on 11 June 2011There's no room for a climate of denial
Dikran, Maybe, but how many natural disasters can you name from 1998? That is only 13 years ago, and occurrances do not come to my mind rapidly. Yes, I can remember the earthquakes from the past few years, the tsunami in Indonesia, and hurricane Katrina. However, before that, everything becomes a little bit fuzzier. I can remember the names of major hurricanes and areas that were hit by floods, earthquakes, and other disasters, but I cannot tell you when they occurred. In fact, had he picked any other year in the decade of the 50s, I probably could not identify a particular disaster. The "top of your head" only works well for recent memory, or for those events that yield a lasting impression on an individual (I am sure all the residents of New Orleans will remember the year that Katrina hit, long past the time that the rest of us forget). Off the top of your head, name a disaster from 2007. -
dhogaza at 03:40 AM on 11 June 2011Geologists and climate change denial
"Touble is, garethman, we're a wee bit short on evidence that casts any significant doubt " Obviously, that's because "Any contrary evidence should be suppressed" (snort). This is blind faith at its worst ... there must be contrary evidence and since we're not seeing it, obviously it's suppressed. The possibility that there's no contrary evidence is not a possibility. -
Albatross at 03:36 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
A new study out documenting the loss of snow pack in the northern Rockies by Pederson et al. (2011): "In western North America, snowpack has declined in recent decades, and further losses are projected through the 21st century. Here, we evaluate the uniqueness of recent declines using snowpack reconstructions from 66 tree-ring chronologies in key runoff-generating areas of the Colorado, Columbia, and Missouri River drainages. Over the past millennium, late-20th-century snowpack reductions are almost unprecedented in magnitude across the northern Rocky Mountains, and in their north-south synchrony across the cordillera. Both the snowpack declines and their synchrony result from unparalleled springtime warming due to positive reinforcement of the anthropogenic warming by decadal variability. The increasing role of warming on large-scale snowpack variability and trends foreshadows fundamental impacts on streamflow and water supplies across the western United States." More here. -
skywatcher at 03:25 AM on 11 June 2011Geologists and climate change denial
Touble is, garethman, we're a wee bit short on evidence that casts any significant doubt on the prevailing theory of climate. In fact most evidence emerging tends to paint a picture of effects happening more rapidly than previously thought (e.g. Arctic ice melt). I'm rapidly getting to a certain age, and I enjoy a good steak, but I see the scientific rationale behind cutting carbon emissions a.s.a.p. very clearly indeed. There is no (sensible) two sides to the science - if there are sides, it's either that climate disruption, already arriving at a doorstep near you, is bad or it's very bad, take your pick... -
Albatross at 03:17 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric_red, To be clear. Do you a) Support Christy's blatant misinformation and attempts to mislead, b) Do you recognize that his arguments are self-contradictory, c) Do you agree that his claims highlighted in the body post are not supported by the overwhelming body of scientific research and evidence?, d) Do you understand that the "we" he refers to actually means a few individuals? It blows my mind that people doggedly and uncritically defend Christy's lamentable actions, and choose to try and fabricate debate and doubt. You have been shown to be wrong numerous time son this thread...yet steadfastly refuse to change your position in the view of the evidence presented to you. In contrast, scientists like Veizer are open-minded enough to change their position in light of new evidence-- as they should. Give it up already...or are you in denial like Christy? -
JMurphy at 03:02 AM on 11 June 2011Geologists and climate change denial
garethman wrote : "It has been my observation of young people in Climate camp etc, that they are much more radical in their beliefs, in fact to the extent that they occasionally do not believe evidence should ever be used to prove or cast doubt on Climate change, we should just believe. Any contrary evidence should be suppressed, cars should be banned and veganism imposed by law. You get the picture" Picture ? More like a fantasy story created to try to claim that there is a hidden and evil left-wing Stalinist/Leninist/whateverotherLeftist conspiracy comprising tyrannical lefties (did I mention the Lefties ?) who want to drag us all back to caves, where we can eat grass and dirt on pain of death. Get a grip. -
dhogaza at 02:55 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
Of course, garethman, there's this informative and easier to read graph from cryosphere today, which shows their area data is totally consistent with the extent data from NSIDC:
That's one hell of a flattening off we're seeing there, dude. Of course this doesn't show the linear regression but the summer (green) line in particular shows clearly that the area minimum for each of the last four years lies well below the linear trend, just as it does for NSIDC, and I'm certain that analysis done on this data would show an accelerating trend, just as it does for NSIDC extent data.
Maybe not such a nice try, garethman, it was more lame than I first thought given the wide variety of data available at cryosphere today.
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dhogaza at 02:50 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
garethman:We must accept that this chart is just propaganda and there is in fact no stabilisation of ice at a substantially lower level than average.
It's not consistent with your point as the september area minimums there are totally consistent with the NSIDC extent graph I showed above. You really need a graph like the Hamilton posted above by DB that shows month-to-month comparisons as it's almost impossible to do month-to-month comparisons on the cryosphere today graph you're showing. The fault isn't with cryosphere today, the fault is with your eyeballs, and possibly the fact that you're unaware that variability at maximum and during the early melt season is much smaller than the september minimum in the first place due to geographical constraints (in much of the arctic, freeze-up is right up to the continental shores and of course it's impossible for further sea water to freeze afterwards because continents are made of land, not water). There's a reason why researchers and amateurs alike focus on the september minimum, when geographical boundaries play a minimal role in the extent and area of sea ice. Nice try, though. -
Dikran Marsupial at 02:46 AM on 11 June 2011There's no room for a climate of denial
Eric the Red Tom said "of the top of your head list the natural disasters of 1954" (emphasis mine). If you can only remember the one tornado, then then your answer is not very complete and you have illustrated Tom's point quite neatly. -
garethman at 02:44 AM on 11 June 2011Geologists and climate change denial
DSL Garethman, I have to take exception at your use of "alarmist." You imply that "alarmist" and "denialist" are binary opposites. That's clearly not true. You also fail to define "alarmist." Can you point out any poster on this site who you would consider to be an "alarmist"? And could you point out any climate scientist who you consider to be an "alarmist”? Garethman. Hi DSL, I have this idea that human beings cover a range of beliefs and emotions. Therefore, logically there are alarmists if if we recognise there are any other type of personality. If you are happy to see denialists in the post, you must ( or hopefully!) also have the understanding that terms are relevant and subjective and if you are OK with using them, I imagine you are happy to extend that right to others.. My main point, to return to the discussion point was that the previous poster had correlated “denilaism” with Geologists of a certain age. It has been my observation of young people in Climate camp etc, that they are much more radical in their beliefs, in fact to the extent that they occasionally do not believe evidence should ever be used to prove or cast doubt on Climate change, we should just believe. Any contrary evidence should be suppressed, cars should be banned and veganism imposed by law. You get the picture This is healthy. Don’t panic or be alarmed. Young people go through this phase, it’s part of their development. Old duffers like myself tend to take more persuasion to move from our life long beliefs. Hopefully we all get there eventually and we all believe we must do something constructive to stop the damage being inflicted on our environment by ourselves. As long as we are not too “holier than thou” It’s a pretty broad church. By the way, I don’t think alarmists are on the opposite pole from revisionists , But I do think they are on the same continuum from complete and utter obsessive adherents tolerating no questions or doubts, to complete doubters who do not think in a logical or evidence based manner and are not really connected to the world as we know it. You are also right, in I have not seen any of them on this wise site, but if they are human, trust me, they are out there. Maybe someone could propose a continuum correlating professions to their place on the line? Such pigeon holing or reductionist concepts would provide at least entertainment if lacking methodology or illumination. -
chris at 02:44 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric the Red at 02:29 AM on 11 June, 2011 Come on Eric, you've just been shown here and here that the evidence doesn't support that tentative hypothesis of Veizer and Shaviv. Veizer himself has reinterpreted the temperature part of the apparent correlation in the paper you cite and reinterpreted it. Veizer now considers that the temperature correlates with atmospheric [CO2] at least throught the Paleozoic part of the Phanerozoic. It's pretty desperate to base interpretations on an old paper that has been shown subsequently to have little scientiic merit, and which (at least one of) the authors now consider to be incorrect! -
Eric the Red at 02:31 AM on 11 June 2011There's no room for a climate of denial
Tom, Those of us who grew up in Michigan are well aware of the devasting Flint tornado of 1954 to which the recent Joplon tornado is compared. -
Eric the Red at 02:29 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Spaerica, Fine, this should satisfy both your requests. http://www.juniata.edu/projects/oceans/GL111/celestialdriverofclimate.pdf -
chris at 02:25 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Re the top article, Hansen's interpretation that climate sensitivity might be amplified (as much as doubled) due to very slow feedbacks, especially associated with slow ice sheet responses in glacial periods (we're in a glacial period now), is supported by other recent analysis of greenhouse gas/temperature responses from the deep past: J. Park and D. L. Royer (2011) Geologic constraints on the glacial amplification of Phanerozoic climate sensitivity American Journal of Science, 311, 1-26 abstract M. Pagani, Z. Liu, J. LaRiviere & A. C. Ravelo (2010) High Earth-system climate sensitivity determined from Pliocene carbon dioxide concentrations Nature Geoscience 3, 27 – 30 abstract D. J. Lunt, A. M. Haywood, G. A. Schmidt, U. Salzmann, P. J. Valdes & H. J. Dowsett (2010) Earth system sensitivity inferred from Pliocene modelling and data Nature Geoscience 3, 60 - 64 abstract -
Albatross at 02:24 AM on 11 June 2011Climate Consensus on a T-shirt
DSL @25, I share your concerns; the Galileo movement will be up in arms ;) Hopefully this will be one of a series of T-shirts that portray/reflect the many independent lines of evidence that corroborate the theory of AGW. -
Alexandre at 02:24 AM on 11 June 2011Geologists and climate change denial
CoalGeologist at 08:19 AM on 10 June, 2011 Very interesting description. Looks plausible. About the "left-wing conspiracy" bit: I've come across many different versions of that argument. - an imperialist conspiracy to keep poor countries poor - a Thatcher conspiracy to harm labor rights (don't ask me to explain...) - an Al Gore conspiracy to raise taxes (I wonder how the Gore family managed to co-opt Tyndall back then. Very long term goals!) - a developing country plot to harm American and European economies -
garethman at 02:12 AM on 11 June 2011Impacts of a melting cryosphere – ice loss around the world
Dhgoza It's almost as though garethman isn't aware that the three years following 2007 are *all* lower in minimum extent than any other year in the satellite record, and that two of the three were well below the long-term trend, and the third right on the trend, isn't it? Aplogies Dhgoza, I was led astray by that well known denialist site Cryosphere today. Have a look at the sort of information they are brazenly publishing to lead all good men astray and lead to the sort of post which you have quite rightly criticised. We must accept that this chart is just propaganda and there is in fact no stabilisation of ice at a substantially lower level than average. http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png -
Tom Curtis at 02:08 AM on 11 June 2011The Critical Decade - Part 3: Implications for Emissions Reductions
One thing that perplexes me about the second diagram is the elevated end point for the 2011 start. By eye, each curve has the same area underneath it. That means each strategy uses the full permissible Carbon budget by 2050, but that in turn will mean the early start/ slower reduction approach will need to cease all remaining production instantly in 2050. Presumably a better approach would to be to have slightly higher initial reductions and to reach zero emissions some time after 2050. In that case the rate of reduction for a 2011 start will be higher than 3.7%, but still less than 5.3%. -
Tom Curtis at 01:52 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
chris @56, thank you for the link. I was not previously aware of that paper, which is interesting. Sphaerica @54, I went through the rounds on his material some time last year. Luckily for me some of it stuck. Dikran Marsupial, thanks. -
Alexandre at 01:51 AM on 11 June 2011The Critical Decade - Part 3: Implications for Emissions Reductions
Important data, in a form that is easy to communicate. Great post, Dana. -
Eric the Red at 01:46 AM on 11 June 2011Climate Consensus on a T-shirt
Tom, Detroit, I think the change from global warming to climate change just caused confusion. Using global climate disruption will add even more fuel to the fire. Out of habit, I have stuck with global warming, but see people using the terms interchangeably. As far as the shirts and mugs go, I dislike them all. Mainly because I am not a big fan of using the Doran survey. -
Bob Lacatena at 01:43 AM on 11 June 2011Climate Consensus on a T-shirt
Consider this (although maybe it still could be a little darker, or more saturated, on the lettering):
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KR at 01:36 AM on 11 June 2011Climate sensitivity is low
MajorKoko - Feedbacks are amplifications (positive) or dampenings (negative) of a forcing change. So they're related to changes in T, not T itself. That said, there are definitely phase changes (melt of clathrates, lack of summer ice in the Arctic, etc.) where feedback levels can be expected to change. As to the original statement: "basically if there is some large negative feedback which makes the sensitivity too low, it would have prevented the planet from transitioning from ice ages to interglacial periods" The Milankovitch cycle forcing change between ice age and interglacial is estimated to be on the order of 3.4 W/m^2, for a direct forcing change of ~1C. Global temperature changes for those cycles, however, are on on the order of 5-6C or so. So a short term sensitivity of ~3C for a doubling of CO2 (3.7 W/m^2) with additional long term feedbacks (ice melt, vegetative changes, CO2 temperature/solubility changes from deep ocean, etc) matches the feedback amplification seen in the ice age cycle. -
Bob Lacatena at 01:35 AM on 11 June 2011Climate Consensus on a T-shirt
I think the second is more effective because it puts the visual emphasis (many people are visual) on the relative quantities, and the words are there for clarification. The first would be okay, if the figures in the back popped more, maybe by using a lighter shade for the words (or darker shades for the bodies), or by using outlines instead of solid coloring for the words. -
chris at 01:34 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
Eric the Red at 21:58 PM on 10 June, 2011 Eric, remeber that Veizer himself has reinterpreted the sea surface data you cite and concludes that his temperature reconstruction now indicates a coupling to CO2 concentrations, at least throughout the Paleozoic: R. E. Came, J. M. Eiler, Ján Veizer, K. Azmy, U. Brand & C. R. Weidman (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era Nature 449, 198-201 -
Bob Lacatena at 01:32 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
52, Eric the Red, You response sounds rather dismissive, as if you want to put all of your emphasis Viezer, and see no reason to be skeptical about it. This thread is about climate sensitivity. We're discussing climate sensitivity. Viezer, Royer, Shaviv, etc. are all about climate sensitivity. So suddenly someone doesn't like the idea of discussing the topic? Is it only fun to wander off topic, and bring up things that belong on other threads? WTF... -
Bob Lacatena at 01:30 AM on 11 June 2011Christy Crock #6: Climate Sensitivity
51, Tom, Excellent work (did it take much, or did you know this off the top of your head?), and once again you've demonstrated the need for a database which makes it easy to realize which papers, while published, were later refuted or amended in some way. It's too easy for people to find a paper that says what they want, and then put 100% stock in it (and as I said, my reading of the original paper seemed like the authors were more raising questions, and admitting to gaps in knowledge themselves, and the need for further investigation, rather then putting a stake in the ground and making specific, hard claims).
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