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Comments 130551 to 130600:

130551. Quietman at 22:08 PM on 30 April 2008
        Can animals and plants adapt to global warming?
        Steve L P.E. is the Punctuated Equilibrium hypothesis put forth to exolain rapid changes in evolution on the species level. In Gould's view mutations occur under stressed conditions more rapidly, increasing diversification. In this view, while the parent species may become extinct, its offspring live on as several new species, of which at least one lineage has a higher probability of survival. In this light, there is no net loss, only change.
130552. Steve L at 08:47 AM on 30 April 2008
        Can animals and plants adapt to global warming?
        Quietman, what's P.E.? You seem to be promoting the idea that extinction is "good" because it improves opportunities for the surviving species. Although it's obvious that niches that have been opened invite evolutionary explosions among surviving lineages, I think it's unclear that extinctions are "good". Before I get too worked up about it, I should ask exactly what you mean. I should also ask what you mean about newly discovered species. Are you talking about new speciation events or new description of products of ancient speciations?
130553. chris at 07:46 AM on 30 April 2008
        Do cosmic rays cause clouds?
        Francois, on skepticism: Skepticism only has meaning with respect to some specific thing. This site seems to be about examining skepticism with respect to the science on global warming. Otherwise we’re all skeptics I would have thought, and we can apply our skepticism wherever we feel it appropriate to focus it. And then it comes down to the quality of the evidence. So addressing your point: [I find it funny that when it comes to cosmic rays, anything but a perfect correlation is taken as a refutation. But for greenhouse gases: "El Nino's, La Nina's, volcanic aerosols, the solar cycle and various stochastic elements of the climate system will all act to modulate the greenhouse enhanced temperature increase, sometimes countering this and sometimes adding to it. "] No one is asking for "perfect correlations", but we should be skeptical if the correlations don't exist or they seem to be somewhat contrived, or they correlate variables only over very short time periods, or they're reported 8 years ago, with no subsequent supporting data in the meantime, but only contrary data...and so on. We should be skeptical, for example, of assertions of cosmic ray flux contributions to the warming of the last 100 years. During the period when we've been able to assess the CRF (since around mid 1950's) there isn't any correlation, and 'though cosmic rays may have contributed to temperature changes/fluctuations during periods before direct measurement of the CRF was made, there's little evidence for this, and unless someone comes up with a compelling argument for including CRF effects in the Earth's "heat budget", there doesn't seem much scientific basis for asserting a significant role. Now you may argue that the fact that we haven't yet got much evidence for this contribution, and as a result we haven't got a good handle on its quantitation, doesn't negate the possibility of a significant potential CRF contribution. However we do know that the Earth can undergo a marked global scale warming under the influence of a rather large "heat budget" imbalance, without any solar contribution whatsoever, let alone a contribution from the CRF. So if we are assessing the cause of the large scale warming of the last 30-odd years and its implications, we don't pretend that factors that are demonstrably of little significance are not so. That doesn't mean that all sorts of solar contributions (CRF included) didn't make significant contributions in the past and won't in the future. All the other things "El Nino's, La Nina's, volcanic aerosols, the solar cycle and various stochastic elements of the climate system..." we know do make a contribution, if only transiently. We can measure these directly, even if we can't predict them (obviously we can predict the solar cycle, but not it's "strength"). We know that they result in transient modulation ("noise") of the Earth's equilibrium temperature (if the latter is at equilibrium), or of the transition to a new equilibrium temperature if there is a forcing that causes the Earth's "heat budget" to be in imbalance. We know that the Earth's "heat budget" is in imbalance. The Earth has warmed rather markedly over the last 30-odd years. This might have been due to an increase in solar output during this period. However we've measured this, and we know that it wasn’t. There may be an effect of the CRF on cloud formation. The evidence is inconclusive, although we're willing to accept that there might be an effect, and we await some compelling evidence. you say: "The CR-climate link may be complex and subtle..." Quite so. It's so subtle as to (so far) escape characterization by a considerable amount of scientific analyses.
130554. chris at 07:32 AM on 30 April 2008
        Do cosmic rays cause clouds?
        Wondering Aloud, I'd like to address each of your comments in turn, since you've made a list of odd statements (apart from the first one!). ["I find interesting the claim that for 500 million years CO2 levels have correlated well with temperature!"} Absolutely. It is interesting and your exclamation mark is not misplaced! ["This only applies at all if you assume it is the temperature change causing the CO2 level change. I would be more convinced by your arguments if you could force yourself to leave this out of them. Past temperature swings cannot be explained by the relatively small CO2 level swings that follow them."] That's certainly incorrect and is a decidedly false premise. Why should we assume such a thing? After all we know that the warming at the Paleo-Eocene Thermal Maximum is likely due to massive release of greenhouse gases (methane likely predominant)...that the massive tectonic events associated with the formation of the Deccan Traps in now-India released large amounts of greenhouse gases around the time of the end-Cretaceous warming...a paper in last weeks issue of Science (April 25 2008) on the revised timing of argon-argon radiodating re-emphasises the likely role of the Serbian Traps eruptions in the Permian-Triassic extinctions....we know that long term weathering process can draw down atmospheric CO2 and result in cooling....that the earliest major glaciations in Earth's history may be explained by the destruction of atmospheric greenhouse methane from the rise of O2 in the late Archean...and so on... You are making a major logical error based, I suspect, on your understanding of the ice-age cycles. Obviously the primary driver of these processes was the achingly slow variations in the orbital properties of the Earth (Milankovitch cycles), and the greenhouse-induced warming was a feedback that enhanced the primary warming. But you make a big error in equating these either with the events in deeper paleohistory or even with the current warming. During the last glacial - interglacial transition, the atmospheric CO2 rose from around 180 ppm (glacial) to 280 ppm over 5000 years or so, in response to Milankovitch warming. That's a rather small amount produced at a slow rate (around 2 ppm per century averaged over the whole transition even if most of might have been produced during the earlier stages). We're raising atmospheric CO2 at more than 2 ppm per year now (100 times faster). And the past CO2 swings were certainly not "relatively small"! The warming at the Permian-Triassic boundary was associated with a rise of atmospheric CO2 to over 3000 ppm. Is that "relatively small"? Warming episodes in the Jurassic were associated with atmospheric CO2 levels that appear to have reached around 6000 ppm. "relatively small"? Warm periods in the Silurian and Devonian had atmospheric CO2 levels around 3000-4000 ppm...and so on. These are not "relatively small" changes. And the evidence indicates that the temperature changes followed these changes in atmospheric greenhouse gas levels. CO2 is a greenhouse gas after all, and when its atmospheric concentrations are increased a warming response is inevitable. That’s obvious surely…
130555. chris at 06:58 AM on 30 April 2008
        Do cosmic rays cause clouds?
        shawnet, I don't think we're talking past each other. We both agree that the very marked warming of the last 30-odd years has had no significant solar contribution, including solar contributions to the cosmic ray flux (CRF). That's very straightforward, and no one disagrees with that. The evidence is rather strong. Svensmark, for example, makes the case for that interpretation, so one cannot assert that the "cosmic ray fluxers" are being "bullied" or ignored or whatever! Might the CRF have some contribution in the future? Might it have had some contribution in the past? Certainly it's possible. We don't rule anything out. So far, however, there isn't much evidence for a CRF contribution to the Earth's energy budget in the past. If we're concerned about the rather marked warming of the last 30-odd years, then we focus our attention to where the evidence lies. It's not the CRF obviously! Might the CRF have some effect on clouds? It's not very clear but the evidence is marginally consistent with the possibility, although the data isn't very compelling at all. After all we had a couple of papers in 2000 reporting a partial correlation....and then nothing but rather contrary evidence since..if the situation is so straightforward, why nothing to support the initial analyses? Might the CRF and its possible effects on clouds have some effect on the Earth's "energy budget"? We don't know. There isn't any evidence for such a possibility, although some have hypothesised such an effect. We await the evidence. Notice that no one disputes that there are many periods in the past of varying surface temperature that don't have any apparent role for the greenhouse effect. The mid-20th century temperature "stasis" was most likely due to atmospheric aerosols from dirty fuels....the warming of the early 20th century probably had a solar contribution (but there's no evidence for a role for the CRF for that event)...the cooling of the Little Ice Age very likely had a strong solar contribution; was the CRF involved? Who can say? There's no evidence for such a contribution...and so on.... ....i.e., no one rejects the possibility of a potential contribution of the CRF to the Earth's Energy budget. There just isn't any evidence for it. As for your comments: "As to whether the majority of the studies support the connection, I will say that the majority that I have seen do so(as do the majority of the papers listed on this thread). We can obviously argue the merits of each individual paper, but I don't think this is a productive use of time." The majority of papers don't support the connection. A number of studies purport to support the connection, but they don't present compelling evidence, and in general follow up studies highlight flaws...even follow-up studies by some of the original advocates. For example Veizer has reinterpreted some of his paleotemperature data, such that the putative "correlation" between the supposed CRF and the Earth's paleotemperature is even less well supported by the evidence. You suggest that it's not a productive use of time to argue the merits of each individual paper. But if we're interested in the evidence that's surely what we should do.
130556. shawnhet at 05:32 AM on 30 April 2008
        Do cosmic rays cause clouds?
        For clarification, my last post when I stated "earthquake" I meant to say volcanic eruptions. Oops! Sorry about any confusion.
130557. Wondering Aloud at 04:51 AM on 30 April 2008
        Do cosmic rays cause clouds?
        I find interesting the claim that for 500 million years CO2 levels have correlated well with temperature! This only applies at all if you assume it is the temperature change causing the CO2 level change. I would be more convinced by your arguments if you could force yourself to leave this out of them. Past temperature swings cannot be explained by the relatively small CO2 level swings that follow them. Reminding us all that CO2 levels cannot explain past climate change is not a great way to convince us that it is the dominant force in current change.
130558. Quietman at 00:04 AM on 30 April 2008
        It's the sun
        NewYorkJ As you are replying to a statement I made I would like to reply. I agree with you, scientists need to be skeptical. My point was that by turning this issue into politics by a movie aimed at inciting the more volatile environmental groups Mr. Gore has created a schism, isolating one group into alarmists and another into deniers. Any skepticism is now viewed as a denial and natural occurrences are blamed on global warming. The alarmisim has done more to hurt the science than help it, pushing govenments into rash actions that are backfiring. In science it is a scientists duty to challenge a new hypothesis and the current CO2 hypothesis is no different. That is how it works. The hypothesis must answer all challengers. The general public does not understand this and calls for action in fear.
130559. Francois O at 23:18 PM on 29 April 2008
        Misinterpreting a retraction of rising sea level predictions
        NewYorkJ No! There is no 11-year solar signature!!! Hey, that's a contrarian argument too! Don't you know that the Sun has no influence on climate? As for Pinatubo, I was just saying that there was no trend up until 1990, so that's before Pinatubo. Furthermore, its effect lasted for about 2-3 years, not a whole decade. I don't see the point in trying to debunk something that does not need to be debunked. If temperatures have been stable since 1998, then so be it! Why twist the data this way or that way, use a running average, remove ENSO, remove Pinatubo, add this or remove that, and say, yes, there is a trend, the trend is still there, don't you see it?! It is as simplistic an argument as saying there is a downtrend since the last 7 years. A trend is a trend only up until it's no longer a trend. It could just be part of a long cycle, as far as I'm concerned. Anyone looking at those graphs objectively would say: there was warming up until 1940, then not much, then warming from 1990-2000, then not much again. Does that disprove AGW? No. Does the existence of a trend prove AGW? No again.
130560. NewYorkJ at 16:30 PM on 29 April 2008
        It's the sun
        "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." How many times have I seen this argument? Thousands of scientists follow wacky environmentalists, worship at the Church of Gore and push "Algorism". This is a general attempt to marginalize the overwhelming consensus view among scientists into a right vs left thing, in order to rally strong opposition through the political sphere. I don't think Gore has done much to affect views. Those who could use convincing are those who would, if anything, want to believe the opposite of what Al Gore says. There's a genuine difference between skeptics and contrarians. All scientists consider themselves skeptics. Contrarians seek to argue a particular point of view, the way a lawyer might.
130561. Quietman at 16:03 PM on 29 April 2008
        Can animals and plants adapt to global warming?
        Excellent post. Extinction cycles and their causes are one of my favorite studies. An extinction cycle weeds out less adaptive species and creates diversity amongst the more flexible species. It should be interesting to see P.E. in action. In fact we may already have seen it in some of those newly discovered species in the same area of the world. This could be a very interesting thread.
130562. NewYorkJ at 14:35 PM on 29 April 2008
        Misinterpreting a retraction of rising sea level predictions
        Good post and good website. It makes sense to remove the "el Nino of the century" anomaly in discerning the trend. Then there's the 11-year solar cycle, which we are now at the minimum on. For a variety of reasons, the "global warming stopped in 1998" is one of the more ridiculous arguments from the contrarian groups, although it's one that is easy to communicate to the layperson, so I understand why it's used.
130563. Quietman at 12:44 PM on 29 April 2008
        Misinterpreting a retraction of rising sea level predictions
        John Sorry,That was supposed to be 1938, 1968 and 1998 for PDO. I don't know how I did that. Sun on the brain I guess.
130564. Quietman at 12:29 PM on 29 April 2008
        Misinterpreting a retraction of rising sea level predictions
        John I don't know what the relationship is yet but mentally put a vertical by at 1918, 1938, 1958, 1978 and 1998 in figure 3 to contrast the graph against the PDO.
130565. Francois O at 11:49 AM on 29 April 2008
        Do cosmic rays cause clouds?
        I find it funny that when it comes to cosmic rays, anything but a perfect correlation is taken as a refutation. But for greenhouse gases: "El Nino's, La Nina's, volcanic aerosols, the solar cycle and various stochastic elements of the climate system will all act to modulate the greenhouse enhanced temperature increase, sometimes countering this and sometimes adding to it. " Like the previous post on this blog, where ENSO effects were removed, removing any warming for a 50 year period where greenhouse gases were increasing... I also find it strange that scientists who study the link between cosmic rays and climate are called "skeptics". Are they not just scientists? Are not those who claim there is no link between the Sun and climate themselves "skeptics"? This blog seems to be about skepticism, but it chooses to be one-sided in its skepticism. For some strange reason, all studies about cosmic rays have some fatal flaws, and there is never ever any error in any paper showing that GHG's are 100% responsible for all disasters past and future! Well, of course, there was the thermohaline circulation thing that was, ahem..., a bit premature... and the hurricane-warming connection that even Kerry Emmanuel has abandoned... were not those flawed "peer-reviewed" papers? The CR-climate link may be complex and subtle, as Usoskin latest paper has shown: there is a regional pattern to cosmic rays. The effect on clouds depends on location, not just latitude. Until the effect is fully understood, parameterized, and included in GCM's, it seems a bit futile to try to refute it with simplistic arguments, and then claim that similarly simplistic arguments should not be used to refute AGW. Just my two cents...
130566. Francois O at 11:03 AM on 29 April 2008
        Do cosmic rays cause clouds?
        I find it funny that when it comes to cosmic rays, anything but a perfect correlation is taken as a refutation. But for greenhouse gases: "El Nino's, La Nina's, volcanic aerosols, the solar cycle and various stochastic elements of the climate system will all act to modulate the greenhouse enhanced temperature increase, sometimes countering this and sometimes adding to it. " Like the previous post on this blog, where ENSO effects were removed, removing any warming for a 50 year period where greenhouse gases were increasing... I also find it strange that scientists who study the link between cosmic rays and climate are called "skeptics". Are they not just scientists? Are not those who claim there is no link between the Sun and climate themselves "skeptics"? This blog seems to be about skepticism, but it chooses to be one-sided in its skepticism. For some strange reason, all studies about cosmic rays have some fatal flaws, and there is never ever any error in any paper showing that GHG's are 100% responsible for all disasters past and future! Well, of course, there was the thermohaline circulation thing that was, ahem..., a bit premature... and the hurricane-warming connection that even Kerry Emmanuel has abandoned... were not those flawed "peer-reviewed" papers? The CR-climate link may be complex and subtle, as Usoskin latest paper has shown: there is a regional pattern to cosmic rays. The effect on clouds depends on location, not just latitude. Until the effect is fully understood, parameterized, and included in GCM's, it seems a bit futile to try to refute it with simplistic arguments, and then claim that similarly simplistic arguments should not be used to refute AGW. Just my two cents...
130567. shawnhet at 08:33 AM on 29 April 2008
        Do cosmic rays cause clouds?
        Chris, I think we are clearly talking past each other here. I concede that the last thirty years of the Twentieth Century are not well explained by the CRF. However, this does not imply that that the effect of CRF on climate is small. It just means that it can't explain the last 30 years on its own. Likewise, a 30 year period with no change in the frequency of earthquakes doesn't establish that earthquakes don't strongly impact climate either. There are also 30 year periods in recent history that are not well explained by an enhanced greenhouse. As to whether the majority of the studies support the connection, I will say that the majority that I have seen do so(as do the majority of the papers listed on this thread). We can obviously argue the merits of each individual paper, but I don't think this is a productive use of time.
130568. chris at 07:28 AM on 29 April 2008
        Do cosmic rays cause clouds?
        shawnet, you state: "There are many points to be made here, but I will constrain myself to just a few. The vast majority of papers on the cosmic ray-climate link do support the idea of such a link. The fact that something else might also be happening for the last 30% of the 20th Century doesn't mean that such a link is not substantial." and then you cite an old paper by Palle Bego and Butler from a journal that isn't indexed in the scientific database. In fact the "vast majority of papers on the cosmic ray-climate link" DON'T support such a link even if they might support "the idea of such a link"! That's the problem. We're back in conspiracy theory mode... Have a read of Palle Bego and Butler [Astronomy and Geophysics 41, 4.18-4.22 (2000)] You'll see that it's a bit of a fishing expedition. The entire time series studied is 1983-1994. They examine a bit of this tiny temporal period and come up with an estimated relationship that they use to extrapolate back in time during periods where there is no cloud cover data (and previous to 1953 where there is no direct CRF data). In short they make a large number of unverified assumptions of which they state "It must be admitted that these assumptions are open to question." and "However, a number of assumptions have been made, which if proved wrong would invalidate these estimates." The fact is that whatever the relationship between the cosmic ray flux (CRF) and cloud formation, there has been no systematic trend in the CRF since the late 1950's and therefore there can have been no CRF contribution to the warming trend of the last 30-odd years. Even the most vocal advocate of the CRF hypothesis (Svensmark) has concluded this. His analysis indicates if anything a mild cooling contribution from solar contributions (CRF et al) since around 1958. In relation to your comment: "No, single factor can explain all the climate variation we have seen over the last several years. CO2 changes don't explain the Solar minimum changes even if they do explain the last 1970-2000. A theory of climate should be able to explain both." I'm not sure what you mean by this. Are you considering year-on-year variation? If so there is nothing mysterious, is there? Within a world undergoing a transition to a new equilibrium temperature under the influence of an enhanced greenhouse effect, one obviously doesn't expect a perfect regular temperature increment year by year! El Nino's, La Nina's, volcanic aerosols, the solar cycle and various stochastic elements of the climate system will all act to modulate the greenhouse enhanced temperature increase, sometimes countering this and sometimes adding to it. That's why one doesn't get too excited about temperature variations over periods of 1-3 or 4 years. 2007 was pretty much indistinguishable from 2005 and 1998 as the warmest years on record. 1998 was lifted by around 0.2 oC above the long term trend by the strongest El Nino of the 20th century. 2005 and 2007 got there without the "help" of a strong El Nino. Right now we're coming out of a La Nina event and we're smack at the bottom of the solar cycle. So we're not surprised if early 2008 has a coolish spell and we don't expect any records to be broken in 2008 and maybe not 2009. However it wouldn't be surprising if the next warmest year on record coincided with the next major El Nino event. Our current "theory of climate" accommodates all of that I would have thought! But there's nothing particulary odd or mysterious about any of this. Svensmark has explicitly ruled out CRF contributions to the Earth's energy budget since the late 1950's pretty much in line with all of the other solar observers. I don't quite see the point of trying to sneak CRF in by the back door by insinuations to various bits of poorly substantiated snippits of unsupported work. If there is some evidence for a CRF contribution to the Earth's heat budget then everyone will be more than happy to accept it I'm sure! After all if it's supported by the evidence then it will have to be taken seriously. At present the evidence is rather dismal, even to the extent that the greatest proponent of the hypothesis (Svensmark) demonstrated several months ago, presumably to his own satisfaction, that there's been no solar contribution (a slight cooling contribution since 1958 if anything) to the Earth's "temperature" since 1958...
130569. Francois O at 06:36 AM on 29 April 2008
        Misinterpreting a retraction of rising sea level predictions
        Is that a peer-reviewed journal? doesn't seem to me. Anyway, it's interesting to see that removing ENSO reveals that there was no significant warming trend from 1935 to 1985. In fact, there only seems to be a warming episode in the 1990's. What's the peer-reviewed explanation? Did CO2 suddenly become a powerful GHG in 1990? Also why did the authors not use the satellite data? Isn't that cherry picking? I'm just teasing. If you pretend to use "peer-reviewed" evidence to counter claims, you can do better than that! Maybe find papers in actual scientific journals?
        Response: The Bulletin of the Australian Meteorological and Oceanographic Society is a peer reviewed journal. Don't forget that 1991 featured a huge volcanic eruption that lowered global temperatures significantly - their analysis finds the global cooling would've been even worse if there weren't El Nino conditions at the time. So global temperatures were recovering from the eruption throughout the 90's.
130570. shawnhet at 02:10 AM on 29 April 2008
        Do cosmic rays cause clouds?
        "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." Hi Chris, There are many points to be made here, but I will constrain myself to just a few. The vast majority of papers on the cosmic ray-climate link do support the idea of such a link. The fact that something else might also be happening for the last 30% of the 20th Century doesn't mean that such a link is not substantial. for instance here, http://www.blackwell-synergy.com/doi/abs/10.1046/j.1468-4004.2000.00418.x?journalCode=aag rays and climate The influence of cosmic rays on terrestrial clouds and global warming E Pallé Bagó C J ButlerArmagh Observatory College Hill, Armagh, BT61 9DG, N. Ireland. Note: Following completion of this paper, the authors were informed by Drs N Marsh and H Svensmark, that they have obtained similar results to those presented here. Marsh and Svensmark’s paper will appear in a forthcoming issue of Space Science Review. Acknowledgements. The cloud D2 datasets were obtained from the NASA Langley Research Center EOSDIS Distributed Active Archive Center. The authors would like to thank K O'Brien, B Bromage and G McCormak for discussions and M Murphy for assistance with computing. Research at Armagh Observatory is grant-aided by the Department of Culture, Arts and Leisure for Northern Ireland. Abstract We analyse the new ISCCP (International Satellite Cloud Climatology Project) D2 cloud data to ascertain if a connection between cosmic-ray flux and cloud cover exists. Despite a previous finding that total-cloud factor and cosmic-ray fluxes were correlated, our results indicate that only the low-level cloud follows solar activity over the full period, 1983–94. Using several proxies for solar activity and the radiative forcing calculated by Ockert-Bell (1992) for the ISCCP cloud types, we estimate the possible impact that such a solar–terrestrial connection may have on climate. We conclude that, possibly excluding the most recent decades, much of the warming of the past century can be quantitatively accounted for by the direct and indirect effects of solar activity. No, single factor can explain all the climate variation we have seen over the last several years. CO2 changes don't explain the Solar minimum changes even if they do explain the last 1970-2000. A theory of climate should be able to explain both. Cheers, :)
130571. 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!
130572. 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
130573. 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/...
130574. 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
130575. 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, :)
130576. 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.
130577. 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.
130578. 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.
130579. 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.
130580. 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.
130581. 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.
130582. 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.
130583. 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.
130584. 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.
130585. 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?
130586. 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?
130587. 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
130588. 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.
130589. 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.
130590. 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.
130591. 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, :)
130592. 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.
130593. 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”!
130594. 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, :)
130595. 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."
130596. 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.
130597. 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.
130598. 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
130599. 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.
130600. 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.

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