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Comments 131851 to 131900:

131851. chris at 20:32 PM on 28 April 2008
        Do cosmic rays cause clouds?
        Robert, In response to my comment: "For example, Shaviv and Veizer, in attempting to assign a period to the putative CRF flux inferred from meteorite “clusters”, use as one of their “parameters” “that which best fits the ice age epochs” (see Figure 10 of Shaviv and Veizer, 2003, GSA Today [P.S. I meant Figure 2!]). In other words they use the climate history as a parameter to “fit” their CRF cycles, and then proceed to conclude that the CRF “fits” the Earth’s climate history. That’s just poor science." you say: Robert: "That is quite an accusation. So, if you don't mind me asking, do you have evidence to support this?" It's not an "accusation"...it's a statement of fact. Shaviv and Veizer say exactly that in their GSA 2003 article. For example, here's the relevant text from the legend of their Figure 2 (see page 6 of Shaviv and Veizer, GSA Today, July 2003) "The blue line depicts the nominal CRF, while the yellow shading delineates the allowed error range. The two dashed curves are additional CRF reconstructions that fit within the acceptable range (together with the blue line, these three curves denote the three CRF reconstructions used in the model simulations). The red curve describes the nominal CRF reconstruction after its period was fine tuned to best fit the low-latitude temperature anomaly (i.e., it is the “blue” reconstruction, after the exact CRF periodicity was fine tuned, within the CRF reconstruction error)." In other words a "CRF periodicity" was assummed and then fitted to a set of metorite cluster data (which is decidely non-sinusoidally-periodic as it happens). This independent sinusoidal variation which doesn't fit the geological temperature record very well in the early part of the Phanerozoic, is readjusted ("fine tuned") "to best fit the low altitude temperature anomaly". It is this "fine tuned" putative cyclic CRF flux (the red curve in Shaviv and Veizer) that is then compared with the paleotemperature record. That seems pretty clear. It's rather clear that Shaviv and Veizer have pre-assummed a sinusoidal CRF flux (for which there isn't compelling evidence), and then assummed that this should match the paleotemperature record (no reason why it should necessarily), and then adjusted the period of their putative sinusoidal flux so that it does fit the paleotemperature record, and then argue that there is a correlation between a putative CRF flux ("fine tuned" to match the paleotemperature record) and the paleotemperature record. One wouldn't get away with that in the research field in which I work....however I expect that it's fair to say that Shaviv and Veizer prepared a rather provocative piece for publishing in the GSA house journal and gave it a title with a question mark; i.e. " Celestial driver of Phanerozoic climate?" The answer to the question would seem to be so far: probably not. The evidence is poor and the paleotemperature data, which actually doesn't have a nice sinusoidal variation at all) fits rather better to the paleoCO2 data as detailed in the recent very comprehensive compilation of Royer (2006; seee my posts above for the citation). As for your statement: "Of course cosmic rays aren't meant to explain ALL of the warming, rather they are meant to represent a large piece of the puzzle, and with other things (including human activities and CO2), attempt to explain this warming." Which "warming" are you referring to? Cosmic rays don't "explain" any of the recent warming (last 30-odd years) at all. Svensmark himself indicates that to be the case. Cosmic rays don't explain any of the warming of the last 150 years, nor any of the warming during the ice age cycles, nor any of the warming throughout the Earth's paleohistory and so on. Now cosmic rays might have some role. But there isn't any compelling evidence for such a role and we know rather categorically that they have played no significant role in the very marked warming of the last 30-odd years. Apart from everyone else, Svensmark says so....he could hardly say otherwise since the data is rather straightforward and compelling!
131852. Robert S at 17:16 PM on 28 April 2008
        Do cosmic rays cause clouds?
        Chris said: "That seems a specious comment to me, since it’s rather clear on re-reading Royer et al (2004), that their absence of “dispute” of the “existence of the CRF/temperature correlation” isn’t some sort of implicit acceptance of the supposed correlation at all! They don’t particularly comment on the CRF/temperature “correlation” since (i) the CRF/temperature “correlation” isn’t really worthy of comment since there’s little evidence that it exists, and (ii) Royer et al direct the reader to an article that rather carefully highlights the gross deficiencies in the Shaviv/Veizer hyopothesis [i.e. Rahmstorf et al (2004)]." It was not an "implicit acceptance," but it wasn't an implicit refutation of the CFR-climate link either, rather it was an attempt to explain CO2s relative role Shaviv gives this summary of his and Veizer's response to Royer: "[Royer et al.] argued that the 18O/16O based temperature reconstructions (of Veizer et al. 2000) has an unaccounted systematic error, due to ocean pH, and hence the atmospheric pCO2 level. Shaviv (2005) considered this effect and showed that instead of an upper limit to the effect of CO2 doubling, of 1°C, Earth's sensitivity increases to 1-1.5°C, but the basic conclusion that CRF appears to be the dominant climate driver remains valid (as later independently confirmed by Wallman 2004)" and "Incidentally, there was a more serious attack on our work, by Royer et al., but it was not about the validity of the CRF/climate correlation. Instead, it discussed the fact that CO2 could offset the geochemical temperature reconstruction. If you take that correction into account and redo the analysis (which Royer et al. didn't) you find that CO2 had a larger role, but still secondary to the cosmic ray flux over geological time scales." Regarding Rahmstorf 2004, Shaviv summarizes his response to them here and why he thinks their response to his rebuttal fails: "every single point they raise is invalid... in their reply to it ["it" referring to Shaviv's rebuttal], they don't address any of the points and simply discuss the statistical meaning of the cosmic ray flux / temperature correlation. In our rebuttal to that, you'll find why their statistical analysis grossly fails, because they unknowingly used Bartlett's formula in a limit where its basic assumption is invalid. In fact, if you redo their statistical analysis without this gross mistake, you realize that the statistical significance of the CRF temperature correlation is at least at the 99.7% level (and this is without the sedimentation or astronomical records)...It is in fact the most significant correlation between any climate variable and a radiative forcing proxy on a time scale longer than a few million years. Moreover, the CRF data and the 18O data are backed with additional, independent data sets, making the link redundant and robust. It implies, again, that the CRF was the dominant climate driver on the multimillion year time scale." Here is Rahmstorf 2004 paper: http://www.agu.org/pubs/crossref/2004/2004EO040002.shtml And here is paper that was in response to Rahmstorf 2004: http://www.phys.huji.ac.il/~shaviv/ClimateDebate/RahmstorfDebate.pdf And here is the Shaviv and Veizer paper that was in response to Rahmstorf's reply to S&V's response to Rahmstorf 2004 (that was a mess): http://www.phys.huji.ac.il/%7Eshaviv/ClimateDebate/RahmReplyReply.pdf On the other hand, Wallman essentially agreed with Shaviv and Veizer: http://www.agu.org/pubs/crossref/2004.../2003GC000683.shtml You then say: "For example, Shaviv and Veizer, in attempting to assign a period to the putative CRF flux inferred from meteorite “clusters”, use as one of their “parameters” “that which best fits the ice age epochs” (see Figure 10 of Shaviv and Veizer, 2003, GSA Today). In other words they use the climate history as a parameter to “fit” their CRF cycles, and then proceed to conclude that the CRF “fits” the Earth’s climate history. That’s just poor science." That is quite an accusation. So, if you don't mind me asking, do you have evidence to support this? You say "maybe the relationship exists…maybe it doesn’t…the evidence is rather unsubstantial." Unsurprisingly, this is where advocates of the CRF/climate theory would disagree with you, and you can find out why by the list of papers I provided above (and there are several I missed). And here is Shaviv's brief summary on the evidence for the link: "Svensmark (1998) finds that there is a clear correlation between cosmic rays and cloud cover. Since the time he first discovered it, the correlation continued as it should (Svensmark, 2007). Here is all the other evidence which demonstrates that the observed solar/cloud cover correlation is based upon a real physical link. 1) Empirical Solar / CRF / Cloud Cover correlation: In principle, correlations between CRF variations and climate does not necessarily prove causality. However, the correlations include telltale signatures of the CRF-climate link, thus pointing to a causal link. In particular, the cloud cover variations exhibit the same 22-year asymmetry that the CRF has, but no other solar activity proxy (Fichtner et al., 2006 and refs. therein). Second, the cloud cover variations have the same latitudinal dependence as the CRF variations (Usoskin et al. 2004). Third, daily variations in the CRF, and which are mostly independent of the large scale activity in the sun appear to correlated with cloud variations as well (Harrison and Stephenson, 2006). 2) CRF variations unrelated to solar activity: In addition to solar induced modulations, the CRF also has solar-independent sources of variability. In particular, Shaviv (2002, 2003a) has shown that long term CRF variations arising from passages through the galactic spiral arms correlate with the almost periodic appearance of ice-age epochs on Earth. On longer time scales, the star formation rate in the Milky Way appears to correlate with glacial activity on Earth (Shaviv, 2003a), while on shorter time scale, there is some correlation between Earth magnetic field variations (which too modulate the CRF) and climate variability (Christl et al. 2004). 3) Experimental Results: Different experimental results (Harrison and Aplin, 2001, Eichkorn et al., 2003, Svensmark et al. 2007) demonstrate that the increase of atmospheric charge increases the formation of small condensation nuclei, thus indicating that atmospheric charge can play an important role (and bottleneck) in the formation of new cloud condensation nuclei. 4) Additional Evidence: Two additional results reveal consistency with the link. Yu (2002), carried out a theoretical analysis and demonstrated that the largest effect is expected on the low altitude clouds (as is observed). Shaviv (2005) empirically derived Earth's climate sensitivity through comparison between the radiative forcing and the actual temperature variations. It was found that if the CRF/cloud cover forcing is included, the half dozen different time scales which otherwise give inconsistent climate sensitivities, suddenly all align with the same relatively low climate sensitivity, of 0.35±0.09°K/(W/m2)." You can find more by Shaviv here: http://www.sciencebits.com/SiteContent I apologize for all the cut and paste, but if I am going to represent a theory, it might be best if I let those who know something about it, explain it. Of course cosmic rays aren't meant to explain ALL of the warming, rather they are meant to represent a large piece of the puzzle, and with other things (including human activities and CO2), attempt to explain this warming. Regards, Robert
131853. chris at 06:33 AM on 28 April 2008
        Do cosmic rays cause clouds?
        Robert, There seems to be something akin to “conspiracy theory” in the approach of the Cosmic Ray Flux (CRF) hypothesisers! You state that Shaviv and Veizer say that: “A quote: "Note that Royer et al. do not dispute the existence of the CRF/temperature correlation of Shaviv and Veizer (2003), only its role relative to that of CO2." That seems a specious comment to me, since it’s rather clear on re-reading Royer et al (2004), that their absence of “dispute” of the “existence of the CRF/temperature correlation” isn’t some sort of implicit acceptance of the supposed correlation at all! They don’t particularly comment on the CRF/temperature “correlation” since (i) the CRF/temperature “correlation” isn’t really worthy of comment since there’s little evidence that it exists, and (ii) Royer et al direct the reader to an article that rather carefully highlights the gross deficiencies in the Shaviv/Veizer hyopothesis [i.e. Rahmstorf et al (2004)]. Now there may be a cyclic variation in the CRF relating to the slow passage of the Earth through the spiral arms of our galaxy, but Shaviv and Veizer don’t present very compelling evidence for such a phenomenon. This putative cyclic variation in the CRF might have a period equivalent to that suggested by Shaviv and Veizer but the evidence for such a period is not compelling. For example, Shaviv and Veizer, in attempting to assign a period to the putative CRF flux inferred from meteorite “clusters”, use as one of their “parameters” “that which best fits the ice age epochs” (see Figure 10 of Shaviv and Veizer, 2003, GSA Today). In other words they use the climate history as a parameter to “fit” their CRF cycles, and then proceed to conclude that the CRF “fits” the Earth’s climate history. That’s just poor science. In the meantime Veizer has reinterpreted his paleotemperature data (for the Paleozoic) and concluded that this fits rather better to the paleoCO2 data (and gives a large “dis-correlation” between the supposed CRF cycle, for which little evidence actually exists! and the paleotemperature data) (Came et al, 2007) , and a wealth of independent proxy paleoCO2 and paleotemperature data provides a non-cyclic variation in the Earth’s surface temperature throughout the Phanerozoic in which the dominant correlate is the atmospheric CO2 concentration. This is summarized in Royer’s very recent compilation (Royer, 2006). What’s concerning about this whole area is the manner in which its advocates engage in trying to bypass the scientific arena to play directly to the “peanut gallery”! Henrik Svensmark is particularly prominent in this dodgy practice. His rather limited and poorly substantiated publications on the CRF/clouds/climate relationship are all very well (maybe the relationship exists…maybe it doesn’t…the evidence is rather unsubstantial), but he then uses these to play fast and loose with a dodgy and rather unscientific book, and a ludicrous website report that is a complete travesty of the scientific method (whatever that might be!....however we can recognise, I hope, that the Svensmark and Friis Christensen (2007) web site “report” that you urled is complete pants). If it’s science it must be about evidence….. Came, R.E., J.M. Eiler, J. Veizer et al (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era; Nature 449, 198-202 Rahmstorf, S 2004, Cosmic rays, carbon dioxide, and climate: Eos (Transactions, American Geophysical Union), 85, p. 3841. Royer, D. L. et al. (2004) CO2 as a primary driver of Phanerozoic climate GSA Today March 2004 pp 4-10. Shaviv, N.J. and Veizer, J. (2003) Celestial driver of Phanerozoic climate?; GSA Today July 2003 pp 4-9 Svensmark and Friis-Christensen (2007) (website “report” http://www.spacecenter.dk/publications/scientific-report-series/...
131854. chris at 06:21 AM on 28 April 2008
        Do cosmic rays cause clouds?
        Hi Shawnet, fair enough about your comments. But I have a problem with this: "There may be something peculiar that happened btw 1970-2000 that overwhelmed/hid the CRF effect, but it remains the best explanation for the *magnitude* of the climate changes during the past. Ultimately, though, the science is still not conclusive. " Of course there is "something peculiar" that happened betwen 1970-2000. It's the massive enhancement of the Earth's greenhouse effect, especially since the massive post-war increase in greenhouse gas emissions that kicked in during the early 1960's. But how can you say that it (the CRF effect) is "the best explanation for the *magnitude* of the climate changes during the past". What's the evidence upon which such an assertion is based??? That's the point... The evidence. If one examines the complete record of contemporaneous proxy-temperature data and proxy-CO2 data, the entire Phanerozoic period (last 500 million years or so) highlights a rather good relationship between the Earth's surface temperature (especially in relation to evidence for mild, medium and strong glaciations) and atmopsheric CO2 [e.g. see Royer DL (2006)]. There is no particularly well-validated relationship between the supposed CRF and the Earth's surface temperature during this period at all. So why bother to assert a relationship with the supposed variations in CRF its supposed effect on the Earth's surface temperature (for which there isn't any particular evidence)... ...in short...where's the evidence??? Royer, DL (2006) CO 2-forced climate thresholds during the Phanerozoic. Geochim. Cosmochim. Acta 70, 5665–5675
131855. shawnhet at 05:56 AM on 28 April 2008
        Do cosmic rays cause clouds?
        Hi Chris, Sorry, reading more carefully, I see that you were likely ascribing temperature variations to TSI, not cloudiness variations(as stated in the opening paragraph). Given that I assume that there is a correlation btw solar proxies of various sorts, my point is that CRF is the most logical cause of that relationship(TSI on its own doesn't change the prevalence of cloud building blocks except by putting a bit more moisture in the air). If you don't accept that there is a relationship btw cloudiness and solar proxies, we are simply talking past each other. My apologies for the confusion. In re, the point about how easy it is to separate CRF from TSI and other factors, it is pretty difficult to do so for the *last few decades* I agree. However, I do think that one can correlate cloudiness with CRF, which does a better job of explaining past behavior, (eg the various solar Minimums), than TSI on its own. TSI on its own doesn't change by enough Joules to explain the MM! There may be something peculiar that happened btw 1970-2000 that overwhelmed/hid the CRF effect, but it remains the best explanation for the *magnitude* of the climate changes during the past. Ultimately, though, the science is still not conclusive. Cheers, :)
131856. chris at 05:29 AM on 28 April 2008
        Do cosmic rays cause clouds?
        Shawnet, I was adressing your comment: “re your comment: "Also, just curious, since you agree that there is solar effect on climate, how do you think that this effect happens. if not at least partly by way of cosmic rays?" My point is that there is zero evidence for a cosmic ray flux (CRF) effect on climate (can you give me some evidence in support of this notion?), and that a solar effect on climate is very easily understood in relation to solar irradiance (or other direct changes in the intensity of solar electromagnetic radiation impacting on the Earth. So in response to your question: “If a direct solar input (say TSI) causes the solar cycle trend in cloudiness, that would imply that increased cloudiness is a function of increased water vapor in the atmosphere correct?” I would say, first, that it hasn’t got anything necessarily to do with “cloudiness”. Why bring clouds into it at all? Surely the dominant solar influence is irradiance (thermal energy!). If the sun burns hotter (higher irradiance) then the Earth will receive a higher flux of UV, IR, light intensity and will be warmer. Why bring clouds into it at all? And second, why should increased cloudiness necessarily be “a function of increased water vapour in the atmosphere”? After all, we know that when the atmosphere warms, the water vapour concentration increases (simple physics of water partitioning between an aqueous pool; i.e. the oceans, and the atmosphere). However a warmer atmosphere has a higher saturation point for water vapour. So why should there be more clouds?? And when you say: “Well, I guess that this is a matter of opinion, but I think that the CRF hypothesis is better than any alternative. It does have some actual empirical support for the formation of cloud condensation nuclei.” Which is in response to my statement that it’s not easy to separate CRF effects from total solar irradiance effects and so on, since these parameters are generally correlated, and certainty so within the 11 year solar cycle…. …I would ask, what is the evidence that the CRF “is better than any alternative”? After all, you are presuming that a doubly uncharacterised effect (the putative CRF effect on clouds that might have an effect on the Earth’s surface temperature) is more significant than a direct total solar irradiance effect that we know has an effect on the Earth’s surface temperature (se the Maunder Minimum and its effects, or the early 20th century change on solar output and it’s likely contribution to early 20th century warming. It’s really a question of the evidence. I think we can agree that the CRF is not very large. There's certainly not evidence that indicates otherwise.
131857. Quietman at 05:06 AM on 28 April 2008
        1934 hits the top ten!
        Will Nitschke You make an argument that would indeed be valid if the comparison was similar territories, but polar ocean vs temperate land does make a difference because of the differenve in water volume of terrestrial glaciers and the polar caps. A comparison of the 48 states to Australia would be somewhat closer.
131858. Quietman at 03:23 AM on 28 April 2008
        Volcanoes emit more CO2 than humans
        A graphic representation of this volcano induced phenomena showing both cooling and warming recent history clearly shows why 1998 was so hot and the cooling afterward.
        Response: I fixed your hyperlink (make sure it starts with http:// - you had the word at in the a href code. Interesting page - I especially like the little dig they have at NCEP to demonstrate how much better their forecast is.
131859. Quietman at 03:05 AM on 28 April 2008
        Misinterpreting a retraction of rising sea level predictions
        John This effect is what I wwas attempting to point out in the Volcanos thread. Not only are the El Ninos more pronounced but the La Ninas as well.
131860. Quietman at 02:57 AM on 28 April 2008
        La Nina watch: March update
        WA In the April Update You can see the correlation between those maps and the change in La Nina. Like I pointed out, it's nearly over.
131861. Quietman at 17:44 PM on 27 April 2008
        La Nina watch: March update
        WA I have posted additional comments on why this area of the map is relavent on the Volcanos thread because the El Nino / La Nina cycle is caused by vulcanism.
131862. Quietman at 17:35 PM on 27 April 2008
        Volcanoes emit more CO2 than humans
        John Using a little circular logic I made a guess at where to place this comment. Sorry if I am incorrect. For starters Volcanoes Unleash El Niño. I had mentioned this in a couple of threads as there does not seem to be an EL Nino thread. But logically, since solar cycles stopped following warming in the late 70s (actually erratic weather conditions started then ie. the ice age scare of 1978-79) we need to take another look at the worst (hottest years) since: 1997-1998 El Niño 1982-1983 El Niño I would like to point out that the triggering and actual cause is volcanic/vulcanism and that these severe cycles must also include the La Nina events that follow each El Nino event. I would also like to point out that prior to the late 1970s there was very little mention of these climate cycles (in the US) other than California where they are very noticeable due to the lack of drastic seasonal changes.
131863. Quietman at 16:37 PM on 27 April 2008
        Volcanoes emit more CO2 than humans
        Recent articles indicate that AGW is not fully responsible for Greenlans glacial melts. von Frese explained. that "under a big place like Greenland or Antarctica, natural variations in the crust will makes some parts of the ice sheet warmer than others." from Magma May Be Melting Greenland Ice he also said "to effectively separate and quantify human impacts on climate change, we must understand the natural impacts too." "The researchers don't yet know how warm the hotspot is, but if it is warm enough to melt the ice above it even a little, it could enable the ice to slide more rapidly out to sea." from Volcano Deep Down Could Be Melting Greenland's Ice Since these articles were printed, I have seen none of the data from the stated conference that by now should be available.
131864. Quietman at 15:57 PM on 27 April 2008
        They predicted an ice age in the 70's
        I well remember this as I was still in college at the time. The winter of '78 was one of the worst. In Buffalo NY the snow along roads was higher than a semi and there were many accidents because you could not see a vehicle approaching an intersection. It was popularized by the television show "In Search Of" at the time hosted by the very popular actor L. Nimoy (Mr. Spock from the original Star Trek). So it had a very wide audience and became very well known.
131865. Quietman at 05:21 AM on 27 April 2008
        Models are unreliable
        Poptech When I was in college we were taguht Fortan IV, even though it had already been supplanted by Fortan 77. I did not realize that anyone was still using it. My own last experience was in SAS and that was in the 90s. Are you saying that these climate models are being coded in Fortran?
131866. Quietman at 15:29 PM on 26 April 2008
        Do growing glaciers disprove global warming?
        John I am not familiar with the number of glaciers. Do you know what percent this is or how they represent all glaciers?
131867. Victor at 09:29 AM on 26 April 2008
        Global cooling: the new kid on the block
        Wondering Aloud, That particular argument was about whether or not a decline in solar irridiance since 1985. It shows no correlation with temperature anyway. But I do believe there's a longer time lag between solar activity and temperature since solar irradiance penetrates deeper in oceans (as I suggest elsewhere on this site). So if solar activity slightly increased past decades it's warming effect could hold on longer but a lag of 35 years seem too long. Another problem is that solar effects mis the temperature peak around 1940 when you lag it. What I wrote about snowcover was my own conclusion simply based on data from the site below. Here you can find information about total northern hemisphere snowcover back to 1966. If you check the list I think you will assume the same. Clearly March had the second lowest snowcover for that month not for every month. About accuracy and calibrations of that data I have still to learn a lot. The same for the GISS-dataset (I wrote 'premature'). GISS didn't took Southern Africa in account which region was colder as average. http://climate.rutgers.edu/snowcover/index.php
131868. Robert S at 16:46 PM on 25 April 2008
        Do cosmic rays cause clouds?
        Chris, The Came et al 2007 paper uses a (relatively) new temperature reconstruction method and Veizer notes here that there is still much uncertainty: http://blogs.nature.com/nature/journalclub/2007/10/francis_albarede.html It is yet to be determined if this method is more accurate. Celestial drivers better explain the GEOCARB Phanerozoic reconstructions, while CO2 fits (somewhat) well with the Came 2007 reconstruction. Regarding Royer 2004, Shaviv and Veizer gave this comment: http://www.gsajournals.org/pdf/online_forum/i1052-5173-14-3-e4.pdf A quote: "Note that Royer et al. do not dispute the existence of the CRF/temperature correlation of Shaviv and Veizer (2003), only its role relative to that of CO2." Despite the Came 2007, the paper still applies... for the most part.
131869. Quietman at 10:44 AM on 25 April 2008
        Evaporating the water vapor argument
        John The argument made by BestTimesNow above here is what I was referring to when I remarked about the Clean Air Act of 1975 in the U.S. a while back. Not only does every car with a cat push out more CO2, it pushes out more water vapoer (both by design) and additionally makes the water vapor acidic from Sulphur Dioxide. This issue becomes more interesting all the time.
131870. Dan Pangburn at 06:22 AM on 25 April 2008
        It's the sun
        I have, so far, only determined that CO2 does not cause Global Warming and that there is no such thing as ‘water vapor feedback’. To my knowledge the combination of factors that contribute to climate has still not been sorted out. The reason why increased greenhouse gas level has no influence on average global temperature is proven at http://www.ruralsoft.com.au/ClimateChange.doc . See more at response 16 to Climate’s changed before.
131871. shawnhet at 04:33 AM on 25 April 2008
        Do cosmic rays cause clouds?
        Hi Chris, If a direct solar input (say TSI) causes the solar cycle trend in cloudiness, that would imply that increased cloudiness is a function of increased water vapor in the atmosphere correct? It is pretty hard to see how decreased water vapor can lead to increased cloudiness. The problem with this is that the direction is the wrong way around, isn't it? We would expect there to be more water vapor in the atmosphere, when it was warmer, hence, it should be easier to become cloudy when the sun is hotter. IAC, are you aware of any studies that compare TSI to cloudiness in the lower atmosphere? I would be interested in these if they exist. "Now it may be the cause that some of these effects were due to solar influences on the cosmic ray flux (CRF). Unfortunately it's not easy to seperate these contributions out. However there isn't really any compelling evidence for a CRF influence on the Earth's surface temperature. When someone comes up with some evidence then I'm sure that we'll all believe it!" Well, I guess that this is a matter of opinion, but I think that the CRF hypothesis is better than any alternative. It does have some actual empirical support for the formation of cloud condensation nuclei. It is entirely possible that the CRF effect is not very large or (more likely) been swamped by some other effect in recent years. The latter would probably be the *most* consistent with *all* the evidence. Cheers, :)
131872. chris at 03:00 AM on 25 April 2008
        Do cosmic rays cause clouds?
        shawnhet: re your comment: "Also, just curious, since you agree that there is solar effect on climate, how do you think that this effect happens. if not at least partly by way of cosmic rays?" Surely the most likely solar contributions to the Earth's heat budget (and thus climate) is the solar irradiance and related parameters. It's very clear that this (or a related parameter that is reflected in the sunspot data for which there is a very good several hundred year old record) can cause very significant effects on the Earth's temperature as indicated by the cold periods around the Maunder Minimum and the possible contribution of rising solar outputs during the early decades of the 20th century. Now it may be the cause that some of these effects were due to solar influences on the cosmic ray flux (CRF). Unfortunately it's not easy to seperate these contributions out. However there isn't really any compelling evidence for a CRF influence on the Earth's surface temperature. When someone comes up with some evidence then I'm sure that we'll all believe it! What we can say is that there's no contribution from the CRF to the widespread and rather significant contemporary warming (since the early 70's). Even the most ardent supporters of the CRF idea consider that to be the case.
131873. chris at 02:48 AM on 25 April 2008
        Do cosmic rays cause clouds?
        Hi Robert, I wouldn’t say it’s my main issue (the absence of trends in CRF during the period of large contemporary warming is a serious issue too)! However it is surely a serious flaw with respect to the notion of a dominant influence of the CRF on the Earth’s temperature during the last 500 million years. Yes, Veizer’s reanalysis applies specifically to the Palaeozoic. However it basically negates the putative relationship between Shaviv’s putative CRF cycle and the Earth’s temperature over one full cycle (i.e. where the putative CRF indicates a cold period centred around 450 MYA, Veizer himself now indicates that the earth was very warm; compare Figure 2 of Shaviv and Veizer (2003), with Figure 2 of Carne, Eiler, Veizer et al (2007). Veizer’s reanalysis indicates that he himself considers his early analyses based on fossil carbonate del-18O were problematic. Presumably other periods of Veizer’s temperature reconstruction may similarly be problematic as indicated by other independent studies (see following); e.g. as described in Royer et al (2004). I really only highlighted Veizer’s reassessment of the Palaeozoic paleotemperature since it was Veizer’s own temperature reconstruction that Shaviv fitted his putative CRF cycles to. However there are many other independent problems with the putative correlation. For example if one examines the entire paleotemperature record and paleoCO2 record (as done for example in Royer’s recent compilations at least with respect to identification of well-defined evidence for significant glacial episodes), the cold periods expected in the Mesozoic (centred around 165 MYA according to Shaviv’s putative CRF reconstruction) aren’t represented in the record (see Royer 2006 reference below). If a major chunk of the Shaviv-Veizer apparent “correlation” is “dis-correlated” (!) by Veizer himself then there’s clearly a problem as is indicated by other independent proxy-temperature data. There’s a more general problem I think which relates to the seductive ease of fitting very grand “cycles” to extremely sparse data sets (paleotemperature/paleoCRF, although the latter is implicitly “cyclic”). With more abundant data (e.g. the Royer 2006 compliation of coincident paleoCO2 and paleo”temperature” data) the historical records look rather more realistic – they don’t seem to be cyclic at all. There are warm and cold periods, and the warm periods are interrupted by spikes of mild, medium or strong glaciations and so on. Now it is possible that the slow passage of the Earth through the long arms of our galaxy has some influence on climate. But it doesn’t seem very convincing in the record, and in fact that data seems to support a dominant temperature-CO2 relationship (as Veizer’s own recent work supports). R.E. Carne, J.M. Eiler, J. Veizer et al (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era; Nature 449, 198-202 D. L. Royer et al (2004) CO2 as a primary driver of Phanerozoic climate; GSA Today March 2004 pp 4-10 D. L. Royer (2006) CO2-forced climate thresholds during the Phanerozoic Geochim. Cosmochim Acta 70 5665-5675 Shaviv, N.J. and Veizer, J. (2003) Celestial driver of Phanerozoic climate?; GSA Today July 2003 pp 4-9 P.S. I’m a common or gardener “Chris” and not “Chris Colose”!
131874. shawnhet at 01:42 AM on 25 April 2008
        Do cosmic rays cause clouds?
        "[ Response: Figure 3 compares the fractional change between neutron counts (solid dots and solid line) & ionisation (open squares, joined by the dashed line). The ionisation modulation is computed for solar cycle 22 for the total ionization from figure 5 of the Usoskin paper. It's the fractional modulation for cycle 22 multiplied by 2 since their fig 6 is a plot of n (which is proportional to the square root of q hence dq/q=2 dn/n, see equ 5 of their paper). This Usoskin paper where Sloan gets his ionisation data is "Cosmic ray-induced ionization in the atmosphere: spatial and temporal changes" published in Journal of Atmospheric and Solar-Terretrial Physics vol 66 (2004) page 1796, presumably the work Usoskin 2004 is based on. I haven't managed to get hold of this paper yet but haven't seen any criticism of the handling of this data from Shaviv or anywhere. The quibbling over neutrons versus ionisation is missing the major point that cosmic ray theory predicts latitude dependence in cloud cover modulation. The crucial result from Sloan and Wolfendale's paper is that cloud cover modulation shows little latitude dependence. ]" Well, first off, whether there is latitude dependence ,is dependent on what latitude dependence looks like(Shaviv thinks it will look different than Sloan). Secondly, if you look at your third figure there you will see that the slope of the muon line is much less than the neutron monitor line(consistent with what Shaviv said). Since, IIRC, muons are the particles that are hypothetically responsible for lower atmosphere atnospheric ionisation, we should be basing our conclusions on that line not the other two. There appears to be some confusion over what Usoskin is actually saying. Both Shaviv and Sloan think Usoskin supports their conclusions. Possibly, one or the other, has misinterpreted the Usoskin results. I found the paper in question, but I must admit it is outside my ability to actually move from there to the calculations in question. http://cc.oulu.fi/~usoskin/personal/JASTP_published.pdf "The ionization of the atmosphere at low and moderate altitudes is fulfilled not by the primary CR particles but by secondaries of a nucleonic–electromagnetic cascade initiated by primary energetic cosmic rays in the Earth’satmosphere. Accordingly, in order to study the cosmic ray-induced ionization, one needs to take into account the development of such a cascade. Here we employed the CORSIKA Monte Carlo package (Heck et al., 1998) which is specially designed to simulate cascade and includes recent and reliable description of various physical processes and cross-sections. Cosmic rays are assumed to consist of protons and a-particles (
        6% in particle number). (When denoting CR energy we mean energy per nucleon, throughout the paper.) In particular, CORSIKA can calculate energy losses deposited by the developing cascade for ionization of the ambient air at every step." Now, I don't know what that means exactly ;) , but it sure sounds more complex than a simple proportion. Also, just curious, since you agree that there is solar effect on climate, how do you think that this effect happens. if not at least partly by way of cosmic rays? Cheers, :)
131875. Robert S at 16:39 PM on 24 April 2008
        Do cosmic rays cause clouds?
        Chris (Colose?), I see your main issue is with Veizer's supposed "reinterpretation" of the data. Veizer's 2000 paper "Evidence for decoupling of atmospheric CO2 and global climate during the Phanerozoic eon." Veizer and Shaviv's 2004 paper "Celestial driver of Phanerozoic climate?" The 2007 Veizer paper you reference "Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era." Notice the difference? The paper your reference is describing coupling during the Palaeozoic era. The Palaeozoic era occurred during the Phanerozoic eon, which is what the 2000 and 2004 papers are about. I don't see any major reinterpretations, rather I see that Veizer found *some* evidence for coupling of CO2 and climate during roughly 1/3 of the Phanerozoic eon. An approximate one-third is still a thorn in the sides of the two earlier Veizer papers, but it certainly isn't enough to come to your conclusion of "...and the putative correlation that Shaviv described in the GSA article is now lost. In other words there is no evidence for a very-long-scale link between the CRF and Earth's temperature."
131876. Quietman at 11:31 AM on 24 April 2008
        Ice age predicted in the 70s
        Sorry John I was replying to ScaredAmoeba "You are repeating the deceitful alarmist allegations made repeatedly by skeptics" Attempting to show that not all skeptical arguments are denials or harmful. If you prefer to delete it thats OK by me, it's your blog.
        Response: Nah, I'll leave it up. One of my pet peeves when having online discussion about global warming is when someone just posts a whole bunch of diverse links to a wide range of topics - it essentially shuts down the discussion because it's not practical to post a reply addressing each link. More constructive debate keeps to the topic at hand. I don't think you were necessarily trying to do this but for future reference, those links would be more effective posted on the appropriate page. Plus from my point of view as webmaster, I like the comments section to be relevant and useful to readers.
131877. Quietman at 07:20 AM on 24 April 2008
        Ice age predicted in the 70s
        These articles all present a case for either natural warming or non-CO2 forced AGW, or simply that the alarmist claims don't quite cut it. Water Vapor Feedback Is Rapidly Warming Europe About the coral reefs: Coral Reefs May Be More Resilient Than Expected "The deniers' fallback position is to argue that what is happening is due not to human intervention but some sort of natural cycle." During the last centuries human methane emissions artificially increased CH4 concentrations to approximately 1750 ppbv: Current Spike In Atmospheric Methane Mirrors Early Climate Change Events NASA Studies How Airborne Particles Affect Climate Change "Tropical deforestation currently accounts for roughly one-fifth of the global emissions of carbon dioxide, the most important human-derived greenhouse gas, Gurney said." Researchers Propose Way To Incorporate Deforestation Into Climate Change Treaty "Whilst rising air temperatures are believed to be the primary cause of recent dramatic disintegration of ice shelves like Larsen B, the new study suggests that the ocean may play a more significant role in destroying them than previously thought." Antarctic Ice Shelf Retreats Happened Before Antarctic Deep Sea Gets Colder My point being that healthy skepticism leads to better understanding of the big picture.
        Response: I'll leave this comment up as there are few links there I wasn't previously aware of. But from now on, I'm taking a zero tolerance policy on comments that post a bunch of links not related to the topic. I know its a bit more work but please post any links on the relevant page.
131878. Quietman at 06:08 AM on 24 April 2008
        Ice age predicted in the 70s
        Re: "You are repeating the deceitful alarmist allegations made repeatedly by skeptics" No, I am not repeating anything. My statement is purely from personal experience. I tried again this morining, after reading your reply, to go back and see if some of the alarmist articles were still there. Most were gone. I checked back through January - gone. What few skeptical articles I had read are still there. I may be ignorant about many subjects but I am not stupid. Those articles were intentionally pulled when proven incorrect. Here are the few that have not been deleted: The rhetoric of climate and slavery Climate change 2007 - a year in review Trees absorbing less CO2 as world warms, study finds Acidic seas may kill 98% of world's reefs by 2050 Deniers of global warming harm us Global warming to trigger volcanic eruptions
131879. frankbi at 03:33 AM on 24 April 2008
        Models are unreliable
        Robert S: Yes, I do know that model parameters are usually adjusted according to some past data, _and_ the resulting model has to be validated with data that are _not_ used to configure the models in the first place. If I didn't make this clear enough, my apologies. From my understanding, this approach of tweaking and holdout validation is what climate scientists have been doing. And it's perfectly good science, of course.
131880. Wondering Aloud at 03:05 AM on 24 April 2008
        Do cosmic rays cause clouds?
        That part I understood I think (re: response in 1). What Shaviv is saying is that for cosmic rays above 15 GeV there should not be increased incidence near the poles. (He doesn't say so but if the magnetic field is not significantly displacing them incidence near the poles should be reduced compared to lower latitudes) So cloud formation near the poles should not be increased if Cosmic Rays are a significant cause. So the entire premise of looking at cloud formation by latitude has nothing to do with the issue. The idea that cosmic rays cause cloud formation is not coming from this debate but rather from seperate direct experiments that clearly show it can do just that.
131881. chris at 23:25 PM on 23 April 2008
        Do cosmic rays cause clouds?
        There are two questions really: (i) do cosmic rays influence clouds formation? (ii) is this effect, if real, significant with respect to the Earth's surface temperature and climates? Robert posted a list of papers that address (i) especially. However I'd say that there are some problems: The Shaviv Veizer analysis of a possible link between the CRF and Earth's temperature on the 100's of millions of years timescale (the GSA Today 2003 paper in Robert's list) rested on a paleo-CRF flux analysis and paleotemperature analysis. However Veizer has reinterpreted his temperature data (see abstract below ***) and the putative correlation that Shaviv described in the GSA article is now lost. In other words there is no evidence for a very-long-scale link between the CRF and Earth's temperature (and in fact the Earth's temperature right throughout the last around 500 million years correlates with the atmospheric CO2 level as Veizer indicates in his recent reinterpretation of paleotemperature data) Many of the papers in Robert's list are essentially neutral with respect to evidence for a CRF-cloud link. Thus Svensmarks Proc. Royal. Soc paper on micro-aerosol formation as a result of ionizing radiation in the lab is not an indication that CRF nucleates clouds in the real world...and so on... However there does seem to be some evidence (some of papers in Robert's list again) that the CRF can influence cloud formation (e.g. the Forbush events correlating transient changes in CRF with transient local changes in clouds). How about (ii) (significance with respect to the Earth's surface temperature)? This seems rather difficult to justify for several reasons. First, there isn't a correlation of CRF with the Earth's surface temperature on any timescale as far as I'm aware (see point about the Shaviv/Veizer analysis above). Second there has been no persistent trend in the CRF during the very marked warming of the last 30-odd years. Svensmark in his website report (http://www.spacecenter.dk/publications/scientific-report-series/Scient_No._3.pdf/view) explicitly demonstrates that the solar contribution (CRF et al!)during the very marked warming of the last 30-odd years is zero (a slight cooling contribution since 1958 if anything). That's pretty uncontroversial. The third general problem relates to the demonstration of the transient changes in local cloud cover in the so-called Forbush events that a couple of papers in Robert's list refer to. How can these processes give rise to a persistent long lived effects? This could presumably only occur with long lived persistent changes in the CRF. Short term local events (like those described as Forbush events if I understand these correctly) won't have much influence. That's partly the thrust of the Sloan/Wolfendale analysis. When the latter authors assess the relationship between Forbush events and cloud data averaged over weeks/months there isn't any correlation at all. Now one could argue that one should analyse only the correlations betwen transient changes in CRF and any transient local changes in clouds. But then the CRF/climate relationship becomes essentially unsupportable, because if there isn't any influence on a weekly/monthly averaged basis, how can there be significant persistent effects on temperature/climate? One explanation for the lack of correlation that might be significant for CRF-cloud-temperature/climate relationship is that the local nucleation of clouds mediated by CRF might relate to super-saturated regions of the atmosphere, which would anyway condense out into clouds by other (non-CRF) atmospheric nucleating species that are known to exist... Overall I would say that the evidence supports the possibility of some CRF influence on cloud formation but this remains to be substantiated, and that the evidence supports the conclusion that these effects are sufficiently small that they haven't provided any evidence in the real world for a CRF-cloud-temperature/climate link. Here's the recent Veizer reinterpretation of paleotemperature data: ***Came RE, Eiler JM, Veizer J et al (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era Nature 449, 198-201. Abstract: Atmospheric carbon dioxide concentrations seem to have been several times modern levels during much of the Palaeozoic era (543-248 million years ago), but decreased during the Carboniferous period to concentrations similar to that of today(1-3). Given that carbon dioxide is a greenhouse gas, it has been proposed that surface temperatures were significantly higher during the earlier portions of the Palaeozoic era(1). A reconstruction of tropical sea surface temperatures based on the delta O-18 of carbonate fossils indicates, however, that the magnitude of temperature variability throughout this period was small(4), suggesting that global climate may be independent of variations in atmospheric carbon dioxide concentration. Here we present estimates of sea surface temperatures that were obtained from fossil brachiopod and mollusc shells using the 'carbonate clumped isotope' method(5)-an approach that, unlike the delta O-18 method, does not require independent estimates of the isotopic composition of the Palaeozoic ocean. Our results indicate that tropical sea surface temperatures were significantly higher than today during the Early Silurian period (443-423 Myr ago), when carbon dioxide concentrations are thought to have been relatively high, and were broadly similar to today during the Late Carboniferous period (314-300 Myr ago), when carbon dioxide concentrations are thought to have been similar to the present-day value. Our results are consistent with the proposal that increased atmospheric carbon dioxide concentrations drive or amplify increased global temperatures(1,6).
131882. Quietman at 18:19 PM on 23 April 2008
        Volcanoes emit more CO2 than humans
        In rereading my comment I see that I misworded it. The entire first paragraph is the first source of heat and what increases it. The Second source of heat is the earth itself released by vulcanism or created by large forest fires. In both cases the soot while airborne will cool but once settled on the ice will warm as far as solar effects go. Both produce direct heat however and the second paragraph explains how internal heat controls weather.
131883. Robert S at 16:58 PM on 23 April 2008
        Do cosmic rays cause clouds?
        Here are a few studies that are in favor of the GCR-climate/cloud formation link (sorry the order is kind of a mess and you have probably addressed a few of them): http://arxiv.org/pdf/physics/0409123 http://journals.royalsociety.org/content/77543w3q4mq86417/ http://www.dsri.dk/~hsv/prlresup2.pdf http://www.spacecenter.dk/publications/scientific-report-series/... http://www.blackwell-synergy.com/doi/abs/10.1111/j.1468-4004... http://journals.royalsociety.org/content/3163g817166673g7/fulltext.pdf https://utd.edu/nsm/physics/pdf/Atmos_060302.pdf http://www.atmos-chem-phys.org/4/2273/2004/acp-4-2273-2004.html http://www.agu.org/pubs/crossref/2002/2001JA000248.shtml http://www.gsajournals.org/archive/1052-5173/13/7/pdf/i1052-5173-13-7-4.pdf http://www.utdallas.edu/physics/pdf/tin_atmtrans.pdf These two studies came out at roughly the same time as the S&W paper: http://aps.arxiv.org/ftp/arxiv/papers/0803/0803.2765.pdf http://aps.arxiv.org/ftp/arxiv/papers/0803/0803.2766.pdf
131884. Quietman at 16:06 PM on 23 April 2008
        Volcanoes emit more CO2 than humans
        Undersea volcanos are indeed active but I don't think that is a big issue. The skeptical argument on volcanos has some merit but not in the way that they are explaining it. First, keep in mind that there are 2 and only 2 natural sources of heat on this planet. The first and more important is the sun. Block the sun and CO2 can have zero effect (it is a feedback). So you do have greenhouse conditions. Second is albedo, soot from volcanos and man-made sources collect over the poles, moreso over the north because that is where industry is largest. This lowers the albedo by darkening the ice. Less active volcanos in the northern hemisphere means that much less soot as well as other greenhouse gas emmitted from eruptions. Note that the south pole is not warming as much, nor south america or africa. The power of increased vulcanism is heat transfer to the ocean that causes upwelling currents and change the direction of air currents in doing so. The best known of these is El Nino/La Nina. See Johns "La Nina watch: March update" on this site.
131885. Quietman at 15:51 PM on 23 April 2008
        La Nina watch: March update
        Also, on the northern part of the March map you mentioned, Mackey had predicted that when enough ice melted covering ocean surfaces, the additional moisture picked up off the water would cause very heavy snowfall in Asia due to the path of the air currents over the pole. He was obviously correct. The march warming is most likely due to aerosol pollutants and particulates that collect over the pole from all over the northern hemisphere. It is being investigated right now.
131886. Quietman at 15:44 PM on 23 April 2008
        La Nina watch: March update
        That is the area of welling up that I mentioned, where El Nino originates. The heated area is full of very active volcanos and the subduction zone is just off shore. The maps show the increase in activity and signal that La Nina is ending soon. This is currently the most active area in "the ring of fire". There are similar but weaker events all around the ring and they have been more active since the late 1970s (strong El Ninos, not as strong La Ninas, but this one is fairly strong).
131887. Quietman at 09:08 AM on 23 April 2008
        It's the sun
        John No offense, but this is an issue that true environmentalists need to take a strong stand on.
131888. Quietman at 09:01 AM on 23 April 2008
        It's the sun
        I believe in taking care of the environment, buying only efficient products and recycling. But these alarmists and violent greens that burn other peoples Hummers really get me. Greenpeace is the worst of all, even one of its founders will have nothing more to do with them. They make me ashamed to say I am an environmentalist because it makes me part of the problem rather than part of the solution. Can't anyone see where rash actions lead? The blame for this is squarely on the UN itself for pushing Algorism and punishing skepticism and the green alarmists pointing fingers at oil companies instead of thinking things out rationally. Come on people, wake up, get off the bandwagon and start using constructive criticism.
131889. Quietman at 08:50 AM on 23 April 2008
        It's the sun
        "Environmentalist Groups Say Tech Firms Get Great Publicity from Their Green PR Efforts, But They Wonder How Deep the Commitment Really Is" But eho are the real Hypocrites? I am now seeing things that I have been afraid of for 40 years.
131890. Carrick at 08:46 AM on 23 April 2008
        Al Gore and Dr Thompson's thermometer
        John, exactly what's skeptical about this? "So while Al Gore was in error attributing the Mann/Jones graph to Dr Thompson, the main conclusion that temperatures during the Medieval Warm Period were less than modern times is correct. This is an important point and seems to be overlooked in the eagerness to debunk Gore. " You're taking this hook line and sinker with absolutely no skeptical inquiry at all. A careful review of the evidence convinces me that the opposite is as at least as likely to be true, namely that it could have been as warm or warmer during the MWP as it is now. The IPCC summary of computer simulations you link above only go back to 1850 and blurs out problems with individual models by replacing the spaghetti curve with a grayed out region. (Errors in the simulations are highly correlated from year to year, the figure makes it seem they are not, which is false and misleading.) Furthermore, there are no reconstructions of temperatures that *don't include tree ring chronologies* that conclude that the MWP was cooler than it is now. And there is every reason to be suspicious of tree rings as proxies for temperature, given the multivariate relationship between temperature, precipitation, and CO2 fertilization on tree ring growth. Even if you ignored CO2 fertilization and precipitation as factors, there is an optimal temperature range for any plant: Presumably in their natural climate (the temperature zones for which they are optimized), you will find them near their optimal rate, otherwise you'd find the plants in a warmer climate than they are actually found. Ecology 101. Lower or *raise* the temperature, and you will see a decline in growth rate. One would certainly not expect anything approaching a linear relationship between the two. (Isotopic measurements of δ18O do not suffer from any of these problems, because they are measuring a ratio rather than an absolute quantity.) I happen to agree that CO2 is playing a role in our current warming trend, but don't agree with Al Gore that it is "appropriate to have an over-representation of factual presentations on how dangerous it is." That's just coded words for lying. And I am not nearly as infatuated with Mann's work as you appear to be. Even the plots the NAS make the answer to whether the MWP appear much less certain that you are portraying it to be: See Figure 11-1 on page 112: Most of the multi-proxy reconstructions show the modern temperature to be about 0.1-0.2 C above that of the Medieval Optimum, which is probably a smaller difference than the absolute uncertainly in the reconstructed temperature for that period. BTW, I don't think it's appropriate to hot link to other people's blogs without getting permission first. I would hope you have done so, or would make a local copy of Steve's figure with a hyperlink to his original image.
131891. Carrick at 08:46 AM on 23 April 2008
        Models are unreliable
        I'm repeating here what I've said in another place on your blog: The IPCC summary of computer simulations you link above only go back to 1850 and blurs out problems with individual models by replacing the spaghetti curve with a grayed out region. (Errors in the simulations are highly correlated from year to year, the figure makes it seem they are not, which is false and misleading.) Also did you notice the huge 0.3°C anomaly around 1940-1950 that the models, even with the fuzzing provided by IPCC, are unable to explain? Where did that warming come from? I would conclude from that, that we aren't at the place yet, even for a 150-year period with a lot of fudge factors thrown in, where we can accurately describe past climate, let alone accurately predict future climate. Secondly did you notice that there was very little anthropogenic forcing before 1970, according to the models? Have you ever considered how disingenuous it is, given this fact, to compare glaciers from e.g. 100 years ago to current, when the models say that almost all warming prior to 1970 was natural?
131892. Quietman at 08:44 AM on 23 April 2008
        It's the sun
        ScaredAmoeba Call for delay to biofuels policy This is why I said that drastic measures without thinking things through could kill us all.
131893. Quietman at 08:42 AM on 23 April 2008
        It's the sun
        ScaredAmoeba Definition of Argument UN food chief urges crisis action Still don't think greens kill out of ignorance?
131894. Quietman at 07:45 AM on 23 April 2008
        Do cosmic rays cause clouds?
        I have to guess that this would come under "other" in Cloud_formation_processes. I have seen articles and blogs all claiming that the cosmic ray hypothesis is false. Is there actually any agreement?
131895. shawnhet at 06:44 AM on 23 April 2008
        Do cosmic rays cause clouds?
        I really don't see that Sloan's response addresses Shaviv's point at all. Presuming Shaviv is right (from his blog) "Another option is to calculate the actual latitudinal dependence of the atmospheric ionization variations. This was done by Usoskin et al. (2004), who took the top-of-the-atmosphere variations in the CRF, and using a *code* to calculate the shower products, calculated the actual latitudinal ionization rate variations. They found that the relative change in the LCC is the same as the relative change in the ion density (which itself is proportional to the square root of the ionization rate). *Both vary by several percent from equator to pole over the solar cycle.* This can be seen in fig. 2. In other words, the latitudinal dependence of the cloud cover variations is totally consistent with the CRF/cloud cover mechanism. *For comparison, the solar cycle variation in the neutron monitor data is almost 20% at the poles, and 5% at the equator.* " (asterisks mine) Since Sloan doesn't dispute this that I can see, he is using the wrong numbers (his proportion is off) to evaluate Shaviv's claims. Cheers, :)
        Response: Figure 3 compares the fractional change between neutron counts (solid dots and solid line) & ionisation (open squares, joined by the dashed line). The ionisation modulation is computed for solar cycle 22 for the total ionization from figure 5 of the Usoskin paper. It's the fractional modulation for cycle 22 multiplied by 2 since their fig 6 is a plot of n (which is proportional to the square root of q hence dq/q=2 dn/n, see equ 5 of their paper).
        
        This Usoskin paper where Sloan gets his ionisation data is "Cosmic ray-induced ionization in the atmosphere: spatial and temporal changes" published in Journal of Atmospheric and Solar-Terretrial Physics vol 66 (2004) page 1796, presumably the work Usoskin 2004 is based on. I haven't managed to get hold of this paper yet but haven't seen any criticism of the handling of this data from Shaviv or anywhere.
        
        The quibbling over neutrons versus ionisation is missing the major point that cosmic ray theory predicts latitude dependence in cloud cover modulation. The crucial result from Sloan and Wolfendale's paper is that cloud cover modulation shows little latitude dependence.
131896. Quietman at 06:26 AM on 23 April 2008
        Antarctica is gaining ice
        John I noticed the ozone portion because it rang a bell fro what I had read previously in Mackeys paper.
131897. Quietman at 05:13 AM on 23 April 2008
        CO2 lags temperature
        In johns skeptic of the week article it says "Moreover, the Earth has experienced no discernible temperature increase since 1998, nearly nine years ago. Remember, too, that the atmosphere is approaching CO2 saturation--after which more CO2 will have no added climate forcing power." This I don't understand. Is this at all credible?
131898. Wondering Aloud at 04:48 AM on 23 April 2008
        La Nina watch: March update
        Somewhat unrelated, but since I linked to it from here... I went to Atomz reference listed. the Map for March shows a Huge temperature spike across Northern and Central Asia. this doesn't fit at all well with all the news reports of huge snow events in China etc. Is the resolution on the map really bad or is the GISS temperature data wrong? I see the hot spot there quietman what are you saying about it?
131899. Wondering Aloud at 01:17 AM on 23 April 2008
        Do cosmic rays cause clouds?
        Shaviv claims that neutrons are the wrong thing to measure and Sloan basically answered "that's all we have", Did I read that right? If Shaviv is right and there is little magnetic field effect above 15 GeV, than neutrons are the wrong thing to measure. I don't know what they claimed about their study but it wouldn't be a representative test for the affect of cosmic rays on cloud formation.
        Response: Sloan's main point is that his analysis comes to the same result whether he uses neutron count or cosmic ray induced ionisation (CRII) rates. Equation 3 equates the cosmic ray component of cloud cover change to a constant K (kappa) multiplied by dN/N - the fractional change in neutron count N. So long as the CRII modulation has the same shape as neutron modulation, equation 3 is still valid.
        
        When Sloan and Wolfendale compared the neutron modulation to Usoskin's CRII data, they were surprised to find that not only was the shape compatible, the absolute values of the fractional change were also. This was why I asked Terry Sloan if he could email me a plot of the comparison of the fractional change in neutron count to CRII - so I could see it for myself.
        
        The bottom line is that both CRII and neutron counts increase at high latitudes so you would expect cloud cover amplitude to also increase. That cloud cover amplitude shows little dependence on latitude indicates cosmic rays are not a major factor in the modulation of cloud cover - if correlation between the 11 year signal in cloud cover and the solar cycle is real, most of it is due to other aspects of solar activity.
131900. Quietman at 12:20 PM on 22 April 2008
        The Mystery of the Vanishing Ocean Heat
        It seems that there is another new twist where the Antarctic Deep Sea Gets Colder. "The data gap can only be closed with the aid of autonomous observing systems, moored at the seafloor or drifting freely, that provide oceanic data for several years."

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