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Will at 23:18 PM on 25 August 2010Greenhouse effect has been falsified
Sorry but these statements are nothing but semantics. The Diurnal Atmospheric Bulge is incontrovertible proof of massive violent top-down atmospheric heating. Please follow the link and read the paper. A greenhouse with a full canopy of leaves completely shielding the ground from direct Sunlight still functions normally. More proof that air is heated by incoming full spectrum electro-magnetic radiation and NOT by OLR. Therefore the "greenhouse effect" hypothesis is false. Ned, Air is rated as one of the top insulators of all substances. That means that air is a very poor conductor of energy compared to most substance. In fact it is one of the poorest conductors of energy there is. What are you trying to describe in your last statement? Conduction or Radiation? -
tobyjoyce at 23:11 PM on 25 August 2010Medieval Warm Period: rhetoric vs science
The Norse Greenland colony, which was started in the 11th century and was abandoned in the 15th century, often comes up in connection with the Medieval Warm Anomaly. There is a very good account of it in Jared Diamond's Collapse. Diamond refers to several book-length accounts, but a shorter older account I have is Magnus Magnusson's Vikings (1980). Magnusson was an Icelander, a scholar and archaeologist woh made it quite big on television in Britain in the 1970s and 1980s. Magnusson's book is an apologia for the Vikings, who (he claims) were misunderstood traders. Hence he emphasises peaceful relations with the Inuit, whereas Diamond suspects the Vikings and the Inuit had primarily an antagonistic relationship. Certainly, the Norsemen never adapted any Inuit technology, which was better suited to the environment than theirs. However, the colony was marginal from the start. It quickly ran short of wood and iron for tools, and used Labrador as a source for each. Farm animals overgrazed the pastures and the short summers made life harsh. Its main export(walrus ivory) was a long distance from the market (Norway) and a difficult journey away. In modern terms, the colony was tiny: about 4,000 people in an "Eastern Settlement", just near the southern tip of Greenland, and 1,000 more in a "Western Settlement" (really North-Western). Diamond suspects the Western Settlement was wiped out by Inuit. Then as now, most of Greenland was ice capped. The colonists and the Inuit eked out an existence from the sea and the coastal strip. As I said above, the Inuit (who were also recent arrivals) had the superior technology and survival skills for the tough environment. There is no need, therefore, to appeal to climate ALONE as the source of the difficulties experienced by the Norse settlements, after their early successes. Diamond makes that clear. Magnusson refers to climate as a suspect in the final collapse but, writing when he did, he calls it the "Little Climate Optimum". So "climate determinism" falls down when the Medieval Greenland colony is discussed - climate may have contributed to its short flourishing period and its demise, but there are multiple other factors which also affected that outcome. -
Berényi Péter at 23:09 PM on 25 August 2010Greenhouse effect has been falsified
#5 Ned at 21:26 PM on 25 August, 2010 A large percentage of the total downwelling solar irradiance is in the near-infrared range, but the atmosphere is mostly transparent in this part of the spectrum That's how transparent it is.
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batsvensson at 23:05 PM on 25 August 2010Can't We At Least Agree That There Is No Consensus?
JMurphy at 03:24 AM on 25 August, 2010 Did you understand what I wrote? -
ecotox at 22:42 PM on 25 August 2010Arctic sea ice... take 2
pikaia is right. The curve would not be linear, as the albedo effect of more dark ocean each year would act as a catalyst. Hence, curving the relationship between ice volume and time. (However, adding another difficult variable to an otherwise simple concept could prove troublesome for politician simpletons and John Q public.) -
Peter Hogarth at 22:26 PM on 25 August 2010The Past and Future of the Greenland Ice Sheet
Berényi Péter at 20:28 PM on 22 August, 2010 As promised, some thoughts on BC (Black Carbon) which I hope are of interest: Globally, over the past century, BC trends have risen, mainly due to low latitude contributions, with a possible tailing off after 1980. In line with previous work Kopp 2010 suggests our best current estimate of global effective Radiative Forcing due to BC is about 0.22 Wm−2. I do not want to downplay the role of BC in regions like the Himalayas, but this thread is about Greenland. Let us look at what the authors and co-workers of the paper you cite have actually said recently on the NH and Arctic regions: Flanner 2009: “Equilibrium climate experiments suggest that fossil fuel and biofuel emissions of BC+OM induce 95% as much springtime snow cover loss over Eurasia as anthropogenic carbon dioxide”; Hadley 2009: “Black carbon (BC) has been measured in snow and ice cores at levels that climate models predict are high enough to be the second leading cause in arctic ice melt and glacial retreat after greenhouse gas warming”; Zender 2009: “our GCM (General Circulation Model) simulations show that dirty snow can explain about 30% of the observed 20th century Arctic warming” Note so far we are talking in the main about simulations. Comparing modeled deposition results from measured observations Gilardoni 2010 we see good agreement in general, but not in the three Arctic sites selected (one of which is Alert, just off Northern Greenland), where measured equivalent BC levels are much lower than global averages. These sites show strong (5 to 10 times higher than background) annual BC peaks (to around 120ng/m3) through January, February and March, when insolation is relatively low. Lamarque 2010 - in support of more accurate simulations (some results shown for Greenland) has introduced a new 150 year global gridded dataset of anthropogenic and biomass burning aerosol emissions, and Hegg 2010 has reported detailed results from much higher spatial resolution measurements of light absorbing aerosols (including BC) in the Arctic. One surprising finding is that the main current source of Arctic BC is biomass burning, and not fossil fuels (as is the case in Eurasia). In the Canadian High Arctic in recent decades we see overall reductions in BC levels from the mid 1980s, with a shift in proportional contributions from Eurasia (due to emission controls) and the US Gong 2010. So what of Greenland? In the early 20th Century BC concentrations (from high resolution ice core evidence) were much higher, and may have changed the summertime surface energy budget by around 3Wm−2 McConnell 2007, however current levels are now significantly lower, and are also lower than global averages. At the same site Sulphate levels continued to rise until the 1980s in Greenland Lamarque 2010. Considering the early 20th century Greenland warming, these results are interesting and it is likely that anthropogenic aerosol effects contributed as has been noted previously by Wild 2009 and others, (see review of more than 20 recent papers introduced by Wild 2010)
(a) Monthly (black) and annual (red) measured BC levels at ice core site D4 in Greenland (71.4 N, 44 W) and (b) relative Winter/Summer levels from site D5, which is approximately 350km further south, from McConnell 2007
Given this evidence it is unlikely that BC contributes to the most recent increases in Arctic surface air temperature and Greenland ice margin melt rates, and is even more unlikely to contribute to warmer waters and warmer Ocean currents causing basal glacier outlet melt and overall accelerated mass loss in Greenland.
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Berényi Péter at 22:21 PM on 25 August 2010What were climate scientists predicting in the 1970s?
#46 gp2 at 23:25 PM on 24 August, 2010 the results clarify that the seemingly mysterious rise in global-mean stratospheric temperatures since 1993 is consistent with increasing stratospheric ozone juxtaposed on global-mean cooling of 0.1 K/decade I still don't get it. After the recovery from the Pinatubo event lower stratosphere temperatures go with no trend whatsoever.
At the same time there is no clear trend in ozone either. Some recovery is seen indeed after Pinatubo, but then it started to decrease again (after 1998, even more so after 2003).
For the same period GISS Surface Temperature Analysis shows at least 0.32°C warming for Global Annual Mean Surface Air Temperature.
According to the Manabe model, we should have five times as much cooling (that is, -1.6°C) in the upper stratosphere. Even if sensitivity characteristics of TLS are taken into account, one would expect at least twice as much cooling in lower stratosphere than the warming rate of the surface. It would mean 0.64°C in the one and a half decades considered (-0.43°/decade).
If Thompson 2009 is followed in that current lack of temperature decrease in lower stratosphere is due to an increase of ozone (in fact it is not), the -0.1°C/decade they find as a residual still seems to be far too small.
It would imply a 0.08°C warming of the surface in 15 years, that is, 75% of the observed warming should come from something else than GHGs (UHI? soot?).
The problem with this solution is climate sensitivity would be less than 1°C/doubling of CO2, that is, water vapor/cloud feedback is strong negative, which contradicts computational climate models.
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Ned at 22:07 PM on 25 August 2010Greenhouse effect has been falsified
Will, the "heat capacity" issue is irrelevant, too. CO2, methane, CFCs, etc. absorb longwave IR radiation, but they then transfer that heat to the rest of the atmosphere via collisions with other atmospheric molecules (roughly a billion collisions per second per molecule). -
JMurphy at 21:42 PM on 25 August 2010Can't We At Least Agree That There Is No Consensus?
scaddenp wrote : "Guys, I think we have given PT enough rope. Moderator Response: Yes, there is no progress in that discussion, so let's just agree to disagree. Enough rope, as well as the hook, line and sinker. In the end, though, those of us with normal lives and outlooks on life, have to know when to call it a day and move on to something more interesting. I get very dizzy going round and round in circles. Any observer should be able to see how warped that list is by now but it will be interesting to see which so-called skeptic tries to link to it next ! (Cue Poptech posting : "I have not been given enough rope. My list is interesting. You have not...etc., etc., ad nauseum) -
Ned at 21:37 PM on 25 August 2010Arctic sea ice... take 2
Mikemcc, yes, you're right -- "albedo" is the average reflectance across either the visible spectrum or the visible & near-infrared range (say, 0.4 to 0.7 or 1.0 or 1.3 micrometers) depending how one wants do define it. The albedo of a surface determines what fraction of the incident light from the sun is reflected. The portion that isn't reflected is, of course, absorbed, raising the temperature of the surface. -
Ned at 21:26 PM on 25 August 2010Greenhouse effect has been falsified
Will writes: Ultimately the fallacious assertions in support of the bogus "greenhouse effect" depend entirely on the ridiculous notion that the atmosphere is heated bottom-up by OLR (outgoing Long-wave radiation). This in-turn requires that the atmosphere is completely transparent to incoming full spectrum electro-magnetic radiation, a large percentage of which is IR. Either you're forgetting the inverse-square law, or you're confused about the distinction between "near infrared" and "thermal infrared" wavelengths. A large percentage of the total downwelling solar irradiance is in the near-infrared range, but the atmosphere is mostly transparent in this part of the spectrum. Only a very small fraction of solar irradiance is in the thermal infrared region. If we look just at thermal infrared radiation, how much of the radiant flux in the atmosphere is from the sun and how much is from the earth? Obviously, the sun is much hotter ... but it's also much further away. Thus, virtually all the IR radiation in the atmosphere is coming from the earth, not the sun:
From Science of Doom
The yellow curve at the left is the blackbody radiation curve for the sun at a temperature of 5780K and a distance of 150 million km. The variously colored curves on the right are blackbody radiation curves for the earth at various normal earth temperatures.
Note, first, that the Y axis is log-scaled. Note, second, that in the thermal part of the spectrum (greater than 3 micrometers) the area under the "earth" curves is much, much larger than the area under the "sun" curve.
Bottom line, the sun heats the earth via visible and near-infrared radiation. The earth emits long-wave (thermal infrared) radiation. Increasing the concentration of greenhouse gases in the atmosphere traps more of that long-wave radiation and raises the temperature of the earth system.
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Mikemcc at 21:19 PM on 25 August 2010Arctic sea ice... take 2
I thought albedeo was primarily a measure of reflection of visible light, since that is where most of the energy is from sunlight. Dark water absorbs more of this energy than white ice. The energy absorbed by the water leads to heating, and some of the absorbed energy is then re-radiated as heat radiation (IR). -
dontcry at 21:02 PM on 25 August 2010Skeptical Science housekeeping: iPhone app, comments and translations
This is really a bit inconvenient to have no information about the user, no link to their profile page. Is it also possible that the email address or website could be displayed like a signature? Like this. Steve Zuc. from Pdfok -
Rob Painting at 20:50 PM on 25 August 2010Greenhouse effect has been falsified
Another question Will - if there's no Greenhouse Effect, why was it warmer in Earth's distant past at a time of reduced solar luminosity?. -
Rob Painting at 20:16 PM on 25 August 2010Greenhouse effect has been falsified
Will, if there's no Greenhouse Effect, why doesn't the Earth freeze over at night?. -
skywatcher at 19:46 PM on 25 August 2010Arctic sea ice... take 2
In that context, fitting a quadratic trend to either the sea ice extent or sea ice volume since 1979 produces a much better fit - ie the losses are accelerating through time, rather than simply declining linearly. Those trends reach zero (in September) for extent around 2030, and volume before 2020. -
Will at 19:37 PM on 25 August 2010Greenhouse effect has been falsified
Which shows that O2 and N2, 99% of the atmosphere, are more sensitive to heat absorption than CO2, 0.0385% of the atmosphere. Also weight for weight O2 and N2 have a higher heat capacity than CO2 which means that if the atmosphere consisted of 50% O2 and N2 and 50% CO2, then the CO2 half of the atmosphere would still be less important with regards atmospheric warming. But the atmosphere is not 50% N2/O2 and 50% CO2, it is 99% N2/O2 and 0.0385% CO2. Ultimately the fallacious assertions in support of the bogus "greenhouse effect" depend entirely on the ridiculous notion that the atmosphere is heated bottom-up by OLR (outgoing Long-wave radiation). This in-turn requires that the atmosphere is completely transparent to incoming full spectrum electro-magnetic radiation, a large percentage of which is IR. Both of which are false. In the following links there is finally incontrovertible proof that the atmosphere is radiatively heated from the top-down by incoming electromagnetic radiation from the Sun. This fact destroys the "Greenhouse Effect" hypothesis which stipulates, bottom-up atmospheric heating via outgoing infra-red. "The Diurnal Atmospheric Bulge, giant 1200º bulge of rapidly heated and expanding gases circling the Globe 24/7." "Diurnal Atmospheric Bulge, incontrovertible evidence of massive top down radiative heating. " -
johnd at 19:04 PM on 25 August 2010Warming causes CO2 rise
Whilst the Mauna Loa CO2 seasonal variation of about 5ppm is not only remarkably consistent and of such resolution that the approximate 2ppm annual increase can be seen, the seasonal variations measured in other various parts of the world are by comparison quite large and vary considerably from region to region. This study,http://www.atmos-chem-phys.net/8/7239/2008/acp-8-7239-2008.pdf provides data from 16 continuously monitored sites where typically the seasonal CO2 variation ranges from 350/360ppm to 390ppm, with one site, Heidelberg Germany typically 370ppm to perhaps 420ppm, (it goes off the scale). With standard deviations of generally 4-6ppm, seasonal variations of these magnitudes must make it extremely difficult to be sure that the annual global increase of perhaps 2ppm is being accurately isolated. Only a small variation in the conditions that drive the natural processes of the innumerable sources and sinks could easily eclipse the relatively small increase especially since many of those processes are not yet fully understood, let alone able to be accurately quantified. -
pikaia at 18:52 PM on 25 August 2010Arctic sea ice... take 2
I really hate the idea of trying to fit a linear trend line to a curve which is certainly not linear! Early in the 20th century the minimum ice extent was fairly constant, but it has accelerated downwards in recent decades. The way things are going, the ice will completely disappear much sooner than the straight line would suggest. -
chris at 17:52 PM on 25 August 2010Medieval Warm Period: rhetoric vs science
gallopingcamel at 14:12 PM on 25 August, 2010 oh dear gallopingcamel, that's simply wrong. I wonder whether you have made any attempt whatsoever to address a comparison of Loehle's and Moberg's reconstruction meaningfully. (i) The reconstruction of Loehle's you are referring to has an embarrassing howler. He didn't understand the convention of dating proxies, and so his "present" that he defined as near 2000 is actually near 1950. In fact his corrected analysis only goes up to 1935. Even taking his deficient analysis (remember he published this in a non-science magazine) at face value, current temperatures in the Northern hemisphere are well above the maximum of his MWP (by 0.3-0.4 oC). (ii) Loehle's baseline (zero oC anomaly) is not the same as those used by climate scientists, which is defined during a period where there is good overlapping proxy and direct temperature measurements. This is normally an average over a period between 1950-1990 (I think Moberg’s “zero” is a 1960-1990 average). Loehle’s “zero” was apparently set by averaging all the data over the entire near-2000 year period. So obviously to compare Loehle’s and Moberg’s temperature anomalies sensibly these have to be normalized to a common zero. You can easily do this by inspection (e.g. lining up the pre-MWP “baseline”; this is around -0.4 oC in Moberg and zero in Loehle). Rescaling Loehle to match Moberg’s zero, puts Loehle’s MWP maximum at an anomaly of ~ + 0.2 oC compared to Moberg’s of around zero. So actually, despite the dismal nature of Loehle’s reconstruction and the embarrassing errors in his analysis, Loehle’s reconstruction isn’t very different to the reconstructions done by scientists (e.g. Moberg). It shows a MWP that was ~ 0.4 (Moberg) to ~0.5-0.6 oC (Loehle) above the pre-MWP temperature anomaly, and around 0.3-0.4 oC (Loehle) to 0.5 oC (Moberg) cooler than current temperatures (in the NH). -
tobyjoyce at 17:43 PM on 25 August 2010The Strange Case of Albert Gore, Inconvenient Truths and a Man in a Powdered Wig
TOP wrote: "The Scopes trial got evolution pretty close to being the codified into law in many places. At least you can't teach or even discuss opposing viewpoints. Interestingly in this example the science has changed so much from what Darwin wrote that he would be laughed out of any current discussion on the topic." This is just not true. Scopes was found guilty and fined. The verdict was later overturned on a technicality. Steven Jay Gould later showed in an essay how school texbooks toned down the presentation of evolution after the case. It is only in retrospective (after a Hollywood movie) that the case looks like a watershed. It was the launch of Sputnik, when the US feared it was losing a technology lead in the Cold War, that revolutionised the teaching of biology. Only in recent years have the courts upheld the banning of religious subject matter (like Intelligent Design and Creationism) in American science classes. No other Western country seems to have that particular conflict. The science has changed from so much from what Darwin wrote? Darwin's observations of evolution and human descent are as fresh today as they were in 1859, and have been backed up a wealth of further studies. What he lacked was a genetic theory of how modifications are passed on. Genetics is a keystone of the Modern Synthesis, but Darwin will always be honoured as the Great Founder, and rightly so. I suppose we would have a good laugh at Galileo's physics, and Bell's primitive telephone while we are poking fun at Darwin. -
ScaredAmoeba at 15:53 PM on 25 August 2010Hansen etal hit a Climate Home Run -- in 1981
factfinder, Certainly not scientific, but a simple but compelling illustration of the infra-red activity of CO2 is shown by Iain Stewart on BBC's 'Earth: The Climate Wars' documentary. -
scaddenp at 15:20 PM on 25 August 2010Medieval Warm Period: rhetoric vs science
GC - now why would we expect a "more balanced perspective" from a paper published in E&E and commented on at CA? The errors were such that Loehle published corrections in 2008. Wouldnt be hard to find other commentary. The only cite I could find in real peer-reviewed literature being by ... Scafetta. What a surprise. Now where was the skepticism in making a critical appraisal of this paper? -
meatbeater at 14:53 PM on 25 August 2010Warming causes CO2 rise
I find it funny that we debate with such emotion over the weather. Determining whether or not human activity is the cause for global warming is also funny. Theoretically we evolved from the Earth and if considered part of the earth, then the Earth's activity causes global warming. If we want to know if anything is unusual then shouldn't we plot the data from ice-core samples in a computer and find out if the derivative of CO2 production in the last 50 years is unusual? From the data that I have seen, I would assume that we are on a cycle that has existed for the last 400,000 years. Ultimately, we should just prepare for the effects of climate change. -
gallopingcamel at 14:12 PM on 25 August 2010Medieval Warm Period: rhetoric vs science
For a more balanced perspective, one needs to compare Moberg's work that gives special weight to tree rings against Loehle's that uses the same data but assigns low weighting to tree rings. The contrast is astounding. According to Moberg the MVP anomaly is a "blip" of around 0.2 Kelvin. Furthermore, current temperatures appear to be higher than they were during the MWP. Loehle shows quite a different picture with an anomaly of around +0.6 Kelvin at 950 a.d., 0.3 Kelvin higher than today: http://climateaudit.org/2007/11/20/the-loehle-network-plus-moberg-trees/ -
scaddenp at 12:27 PM on 25 August 2010Can't We At Least Agree That There Is No Consensus?
Guys, I think we have given PT enough rope.Moderator Response: Yes, there is no progress in that discussion, so let's just agree to disagree. -
Tom Dayton at 11:44 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
daisym, understandably you misunderstand the term "dropped" in "dropped stations." It does not mean deleting the data points. For more explanation, see: 1. The second paragraph of the Intermediate version of this basic post (which is linked in the green box at the top of this page you are reading now. Be sure to click the "Intermediate" tab when you get to that page.) 2. My comments here, here, and here. 3. See an actual example of a monthly temperature raw dataset containing not just temperatures for that just-passed-month, but also a large number of data points for months and even years in the past, which are what put the bump in the older end of the distribution of number of stations reporting. If you don't trust that example, then you can download the data yourself. -
Yvan Dutil at 11:36 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
@daisym The way data are processed removing station has little impact overall. First, climatologist work with the anomaly, which is insensitive to calibration or local climatology. Second, data a weigthed on a area basis. Otherwise, world temperature would be strongly weigthed on USA. As for inclusing data of new sensor, it my not be obvious for you but this is a very tricky process. In addition, data compilation and archiving have a very low priority for grant unless it becomes obvious this is a serious problem. Scientist in every field sufer from that problem. Actually, physicist (which climatologist are a subgroup) fare better than many other type of scientist. -
robert way at 11:25 AM on 25 August 2010Arctic sea ice... take 2
No the data is not available back to then for volume from the polar science center unfortunately. -
BDS2020 at 11:00 AM on 25 August 2010Arctic sea ice... take 2
Is the data available to take the volume chart back to 1950? Would be interesting to see data for the same period for both extent and volume. -
adelady at 09:52 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
daisym. You've got the story back to front. The climate *change* science is just an extension of the physics of stable climate. Nobody thought 90 or 150 years ago that working out the physical properties of carbon dioxide (and other greehhouse gases) would lead to where we are now. When all the basics were worked out, it was just wonderful that the earth and its climate were so perfectly suited to life as we know it. It *was* a parsimonious theory. Everything that was learned about the heat absorbing and emitting capacities of CO2 (and the other gases) explained the temperature and what was known of the earth's history. It is just an accident of history that the expansion of learning has coincided with the expanding release of so much CO2 from fossilised carbon compounds. There were other non-polluting technologies available 100 years ago. Had we pursued them instead of fire based power generation, climate science now would be just an interesting side interest of ivory tower intellectuals. -
kdkd at 09:32 AM on 25 August 2010Can't We At Least Agree That There Is No Consensus?
poptech #69 Your legend in your own mind approach is most tedious. However, thank you for your response. It does a very good job of confirming the validity of what I said at comment #61. Your understanding of science and the scientific process is most deficient. -
daisym at 09:29 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
#5: Context is everything. After collection of data for so many years, from so many places on the globe, it seems strange that the science elites decided against automated reporting efficiencies in favor of deleting 2/3 of the land data points. It's curious that they became parsimonious only after launching 4,000 ARGOS and other automated buoys, mostly in the Northern Hemisphere. There's another definition of "parsimony": Unusual or excessive frugality; extreme economy or stinginess. And there's another application of the law of parsimony which was somehow overlooked by the science elite: Stating the simplest of two or more competing theories is preferable and that an explanation for unknown phenomena should first be attempted in terms of what is already known. Theorizing that natural climate change dominates manmade influences would have been a simpler hypothesis to investigate. They way it was framed served to place the burden of debunking the hypothesis on the skeptics. Context is everything. How was the average global temperature record adjusted to replace missing data from Siberia after collapse of the USSR? It WAS adjusted, right, or did the world get that much warmer overnight? Ditto for urban heat island adjustments. -
NewYorkJ at 09:16 AM on 25 August 2010Hansen etal hit a Climate Home Run -- in 1981
The 1981 paper underestimated warming to a moderate extent. This tends to contradict assertions from the contrarian cult that Hansen is some kind of "alarmist". Regarding the 1988 Hansen paper, RealClimate has an update. Through 2009, the observed trend since projections started is 0.19 C per decade, vs 0.26 C per decade for Scenario B - a little behind but within margins of error. Hansen used 4.2 C for climate sensitivity. The climate sensitivity value for this model that best matches the observed trend is 3.4 C, with large error bars of course. Updates to Model Data Comparisons Annan has a recent post that looks at the 1988 model. While (as noted above) the model drifts a bit on the high side of observations (which Annan attributes to some combination of model characteristics of higher climate sensitivity, low thermal inertia, and lack of tropospheric aerosols), it has clearly demonstrated skill. AnnanResponse: Thanks for those links, I've added them to the list of resources on Hansen's 1988 prediction. -
JMurphy at 08:55 AM on 25 August 2010Can't We At Least Agree That There Is No Consensus?
Poptech wrote : "Did I list Pielke Jr.'s papers because I thought they supported his Hypothesis 1?" No, you listed them because you believed that they were sceptical about AGW (alarmist or not, depending on whether the title or the introduction to your little personal list is most descriptive), despite Pielke Jnr's own views that they shouldn't be on your list. He also suggested that you change the list to be YOUR list and not a list of sceptical papers, which your list isn't - except in your mind. By the way, the list is constantly discredited and any serious person can see this. You do not understand what peer-review is and very few of the papers and journals on your list are properly peer-reviewed. -
Hansen etal hit a Climate Home Run -- in 1981
robhon - No, Spencer in that link is demonstrating the presence of backradiation with an (uncalibrated to atmospheric spectra) infra-red thermometer. Spencer feels that cloud cover provides a negative feedback to global warming which minimizes the CO2 effect (something of a minority opinion), but he's well informed enough to speak clearly about how the greenhouse effect. His post on Yes, Virginia, Cooler Objects Can Make Warmer Objects Even Warmer Still is also worth reading; he shows that the greenhouse effect doesn't violate the 2nd law of thermodynamics, and that a cool object can make a nearby warm object warmer (when the cool object is itself warmer than the background temperature). -
Rob Honeycutt at 06:48 AM on 25 August 2010Hansen etal hit a Climate Home Run -- in 1981
muoncounter... Wow. Just read Spencer's backyard experiment. Am I missing something? Is he actually trying to claim there is NO greenhouse effect? -
GFW at 06:40 AM on 25 August 2010Southern sea ice is increasing
Hi John, found it! (partly thanks to Chris, partly to Stoat (William C.)) Chris, thanks - Manabe et al (1992) is exactly the paper I was remembering, and I finally found the place I saw it described. Bob Grumbine! http://moregrumbinescience.blogspot.com/2010/03/wuwt-trumpets-result-supporting-climate.html Now we have Liu & Curry (2010) that seems to be saying very much what Manabe et al said in 1992. Which I'd say is quite a coup for the latter. -
NASA-GISS: July 2010-- What global warming looks like
johnd - I believe the CO2 time scale for deep warming of the ocean is covered in CO2 lags temperature. It's not an instant effect, and in fact appears to lag 800-1000 years behind an immediate solar forcing, while water vapor has a 5-10 day feedback time constant. But when the CO2 does rise, it induces an additional water vapor feedback. "Production of water vapor from the ocean" is a bit of a misnomer - vapor pressure is determined by temperature, and there's constant vaporization/condensation all the time. Changing temperatures just change the equilibrium point. -
johnd at 05:11 AM on 25 August 2010NASA-GISS: July 2010-- What global warming looks like
KR at 04:49 AM, water vapour is produced when solar radiation warms the immediate surface of either the land or oceans, therefore it provides an immediate response to changes in solar radiation. However for CO2 to be released from the oceans the ocean waters have to increase in temperature, something that happens on a much longer time frame. Given the evaporation that produces water vapour transfers heat from the surface, creating a cooling effect, can you explain how it is not always the warming produced by the water vapour that leads to firstly more water vapour, and in turn even more water vapour before any CO2 at all is forced from the oceans. Would not the production of water vapour from the oceans surface have to cease before the ocean waters could warm at all? -
NASA-GISS: July 2010-- What global warming looks like
johnd - You do get a water vapor feedback to the solar forcing at the end of a glacial era. It's just that with increasing CO2 forced from the oceans, raising the temperature over the solar forcing, you then get an additional water vapor feedback from that temperature increase. -
johnd at 04:44 AM on 25 August 2010NASA-GISS: July 2010-- What global warming looks like
Ned at 19:41 PM, re "without a CO2 feedback amplifying it." You also don't get major forcing based on CO2 without water vapour feedback amplifying it, the water vapour being the major factor. Can you show why the water vapour feedback would not occur without any initial CO2 forcing, instead responding directly to other initial forcings such as solar forcing. -
CBW at 04:39 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
#10, Alexandre, you must know it's about the big money these fat cat scientists make. They have to pay for their fancy cars, yachts, and debauchery-filled gambling junkets to Monte Carlo. So they show less warming now so they can get even more money to show more warming later. -
robert way at 03:53 AM on 25 August 2010Medieval Warm Period: rhetoric vs science
Viau et al. 2006 uses 15,000 years of data and finds a 1050 year cycle with an amplitude of around 0.2°C I believe. Also pertaining to Arkadiusz Semczyszak's commentary. If you took the 1940s and kept the same temperatures as then for years and years then you would see the MCA/MWP. The same forcings and roughly the same amplitude. This is shown in numerous studies (same pattern of warmth even). But the current warming is beyond that of the 1940s and is much more global. I will have to find another reference I saw but they use cosmogenic exposure dating on surfaces revealed by glaciers in the Canadian arctic (on Baffin Island I think) and find that ice covered that area during the MCA/MWP. -
JMurphy at 03:24 AM on 25 August 2010Can't We At Least Agree That There Is No Consensus?
batsvensson wrote : "Can you explain what "the truth" is?" The 'truth' in this instance is : A quick count shows that they have 21 papers on the list by me and/or my father. Assuming that these are Hypothesis 1 type bloggers they'd better change that to 429 papers, as their list doesn't represent what they think it does. Roger Pielke Jr's Blog - Better recheck that list Which is a response to Poptech's belief that "Pielke Jr. made no request to remove papers..." I wasn't trying to claim knowledge of 'The Truth' - Heidegger gave it a go, though : Truth is correspondence. Such correspondence obtains because the proposition is directed to the facts and states of affairs about which it says something. Truth is correctness. So truth is correspondence, grounded in correctness, between correspondence and thing. The Essence of Truth And to carry on the philosophical theme, so-called skeptics remind me of the group of people (from Plato's Allegory of the Cave) who have lived chained in a cave all of their lives, facing a blank wall : Wouldn't it be said of him [that escaped and then returned to the cave] that he went up and came back with his eyes corrupted, and that it's not even worth trying to go up? And if they were somehow able to get their hands on and kill the man who attempts to release and lead up, wouldn't they kill him?" (Plato - The Republic, 517a) -
Alexandre at 03:08 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
gallopingcamel #4, Any hint why they mischieviously ended up with less warming after the drop off? -
dsleaton at 02:54 AM on 25 August 2010Station drop-off: How many thermometers do you need to take a temperature?
Wynnray, I'll provide some evidence for you. My dad died of oat/small cell cancer last year (97% of such cancer patients have smoked or are/were smokers). He smoked until the last week of his life, during which he was bed-bound, and I refused to give him his cigarettes (he was also on oxygen). He never stopped claiming that it wasn't the smoking. Indeed, and I think this part of the analogy fits in some respects with denialists, he once claimed that the cigarettes were killing the cancer. He once convinced a nurse (she also smoked) in the cancer ward to take him outside to have a cigarette (this was a short time before chemo/radiation took down the mass in his lungs to 2% of its original size -- it later came back with a vengeance). -
muoncounter at 02:44 AM on 25 August 2010Medieval Warm Period: rhetoric vs science
#22: "I don't think one can confidently diagnose the existence of an 1100 year periodic cycle from 2000 years of data" Point taken. I saw a low around 500 and another around 1600. Whether or not that repeats is not contained in these data. But if I was modeling these data, I'd start with that long period. I think its pretty certain that you would need higher frequencies to accurately describe what happened at the tail end. And then the question would be: what natural process provides those higher frequencies? And if not natural, then what man-made process? -
muoncounter at 02:36 AM on 25 August 2010Hansen etal hit a Climate Home Run -- in 1981
#9: See also Dr. Spencer's backyard experiment measuring the greenhouse effect. "This paper is more circumstational evidence" Circumstantial? A model run 30 years ago made a prediction of current events that worked reasonably well. In my old business, that would be called a successful experiment (aka an oil and/or gas discovery) and we would be taking $$$ to the bank. In my new (part-time) business, if I predict earth-surface cosmic ray counts based on 'space weather' observed by satellites, isn't that also a successful experiment? (no $$$ in muons, unfortunately). Why is climate science a field where people get called out whether they are right or wrong? -
enSKog at 02:14 AM on 25 August 2010Medieval Warm Period: rhetoric vs science
Re HR's comment "I'm still unconvinced that pasting the thermometer record on the end of a proxy reconstruction is totally valid" the thermometer record IS a proxy record, with the thermal expansion, electrical or optical properties of various materials used as a proxy to estimate the temperature of the atmosphere. They are, of course, very good proxies.
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