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Comments 131951 to 132000:

131951. shawnhet at 03:03 AM on 3 May 2008
        Do cosmic rays cause clouds?
        Chris, I haven't read H&S in a while, but I will make a couple of points. "(ii) Harrison and Stephenson make two points in their paper. If one looks at their Figure 2 and associated text, one sees [point ONE] a very weak correlation between the CRF and the diffuse fraction (DF) (cloudiness – presumably dominated by changes in low-level cloudiness), which [point TWO] breaks down when the CRF is higher than 3600 (x100) per hour. Above this level the DF is independent of the CRF." I will agree that this seems to be a pretty good point against a simple relationship btw CRF and cloudiness. I will have to read H&S again to, and think about it, however, the relationship found by H&S is still statistically significant and is consistent in multiple locations. IAC, I think it is a mistake to claim that the relationship btw CRF and clouds is simple, but it is also a mistake to claim that there is no evidence of such a relationship. Cheers, :)
131952. chris at 23:23 PM on 2 May 2008
        Do cosmic rays cause clouds?
        A slight clarification of my long post. When I say (referring to Harrison and Stephenson's data; e.g. see their Figure 2a) that above a CRF count of 3600 (x100) per hour there is no correlation between the CRF and the diffuse fraction (DF), I really should say no correlation between changes in CRF and changes in DF. Above the 3600 (x100) per hour "threshold", the DF remains high, but loses its correlation with the CRF that is marginally apparent at CRF values below the threshold. And similarly, in pointing out that periods in recent history (last 400 years as indicated by the well-characterised sunspot numbers) like the Maunder and Dalton minima can't have had a contribution from the CRF since the CRF was likely well above the 3600 (x100) per hour threshold during these and other large parts of the last 400 years, I really should say that differences between the surface temperature of the Maunder or Dalton minima (say) and the surface temperature during the period between 1975 and 1925 (say) can't have had a significant contribution from any changes in the CRF, since it's likely that the CRF was already above the threshold value [3600 (x100) per hour)] where changes in the CRF don't result in further changes in the DF (cloudiness), during all of these periods. and in point (iv) I meant "persistent cloud effects" rather than "temperature effects" in realtion to the Sloane/Wolfendale analysis of Forbush events!
131953. chris at 21:48 PM on 2 May 2008
        Do cosmic rays cause clouds?
        Shawnet, I decided to have a good read of Harrison and Stephenson this morning, and have come up with as rather long post for which I apologize. I've tried to organize it coherently: Harrison and Stephenson [Proc. Roy. Soc. A 462, 1221–1233 (2006)] is fine. However I don’t think it provides very good evidence of a CRF contribution to climate. As the authors state “Changes in DF and the frequency of overcast days represent changes in the weather and the atmospheric energy balance.”, and there are a number of considerations that need to be addressed if the effect is to be considered a “climate”-influence, rather than a “weather”-influence. Here are some: (i) The first relates to something that we are all aware of. There isn’t any correlation between these processes and the Earth’s temperature evolution during the period in which the CRF has been monitored in detail. After all the CRF was as high in the period 1950-55 as it is now. High CRF should correlate with high low level cloud and low temperatures. However the Earth is clearly a lot warmer now than in the early 1950’s. Now of course, that’s an unfair comparison, since the CRF varies with the solar cycle, and so one doesn’t expect persistent warming/cooling from an oscillating forcing that has no trend. But that just re-emphasises that the there has been no significant solar contribution (CRF included) to the very marked warming of the last 30-odd years. This has been re-emphasised in two detailed analyses just published by Lockwood/Frolich (see bottom of post [***]). (ii) Harrison and Stephenson make two points in their paper. If one looks at their Figure 2 and associated text, one sees [point ONE] a very weak correlation between the CRF and the diffuse fraction (DF) (cloudiness – presumably dominated by changes in low-level cloudiness), which [point TWO] breaks down when the CRF is higher than 3600 (x100) per hour. Above this level the DF is independent of the CRF. Taken at face value, this seems problematic. Examination of Harrison and Stephenson’s Figure 2 indicates that most of the data in their analysis period (1968-1994) lies in this non-responsive region of the CRF/DF “correlation” where the CRF and DF are apparently completely independent (no correlation). If one examines the entire CRF record [http://ulysses.sr.unh.edu/NeutronMonitor/Misc/neutron2.html], that is reinforced. During around 90% of the entire period between the start of the CRF count (1951) to now, the CRF has been higher than 3600 (x100) per hour [if one looks at the climax CRF/sunspot number plot on the page I urled and compares this with the data in the downloadable datasets on that page one can work out that a CRF count of (3600 (x100) per hour corresponds to around the 83% level].Again one might conclude that that’s additional explanation for the complete absence of a detectable CRF (solar) contribution to the marked warming of recent decades. (iii) This leads to an additional problem (it seems to me), which relates to ascribing CRF climate effects to earlier periods. Although we’re in a solar minimum right now with respect to the solar cycle, the sun is in a relatively “strong” state. If one examines the sunspot data going back to 1600 [e.g. here: http://en.wikipedia.org/wiki/Sunspot], this is apparent. Now if the very strong inverse relationship between CRF and sunspot number (see Climax neutron/sunspot data urled above) was maintained in those periods (no reason to think otherwise), then the CRF was likely generally stronger [greater than 3600 (x100) per hour] during periods like the Maunder and Dalton minima. However taking Harrison and Stephenson’s data at face value, the cloudiness as measured by the DF is completely independent of the CRF at values above 3600 (x100) per hour. Therefore the CRF cannot have played a significant role in the cooling during those periods. We could deal with that problem by making some ad hoc assumptions. Perhaps the CRF became decoupled from the other solar parameters during periods with “weak” solar output. Perhaps the thresholds for a CRF-cloud correlation was higher then than it has been for the past 40 years (one might imagine that in periods where the air is rather clear of man made aerosols, the threshold for CRF effects on cloud formation become higher…and so on). But there’s no evidence for any of these ad hoc assumptions. (iv) One may still question whether the apparent correlation between CRF and DF in the CRF range below 3600 (x100) per hour is due to the CRF and not some other solar-related parameter that cycles in step with the CRF. Harrison and Stephenson used Forbush events in an attempt to assign a causal connection. However the useable Forbush events are apparently very rare (31 days in a 50 year period with CRF count reduction greater than 5%), and so the data is not terribly strong; the Forbush events (0.2% of the record) may not be representative of the other 99.8% of the record. (iv) We come back to the point of whether the CRF-cloud “correlations” are significant with respect to “climate” effects as opposed to “weather” effects. Sloane and Wolfendale’s analysis indicates a lack of detectable temperature effects from the Forbush events. We’ve already seen [see point (i)] that there’s no correlation between the CRF and the Earth’s temperature response since the start of the count, although we recognise that the CRF has been trendless, and so will only be represented in the solar cycle which is difficult to “pick out” in the record since it is smoothed by the inertia in the climate system, and is apparently small with respect to other stochastic variations (El Nino’s, volcanos, La Nina’s), and especially with respect to the strong and persistent trend arising from the enhanced greenhouse effect. (vi) A couple of other points need to be established if the CRF-cloud correlations have potential “cloud” implications rather than “weather” implications: (a) Does CRF-mediated cloud formation result in a nett change in the cloudiness over that resulting from other cloud-forming process (currents that mix warm damp air with cold air; all the other atmospheric aerosols; mountains and land masses). I don't think that's been established 'though Harrison and Stephenson's data might support that conclusion? (b) What about the day/night relationships? According to the CRF-cloud theory, cloud effects act during the day. CRF-mediated cloud formation blocks solar irradiance at the surface cooling the Earth. Notice that the greenhouse-mediated warming acts during both day and night, since the effect results from atmospheric “trapping” of IR radiation emitted from the Earth’s surface that occurs during the day and night. This is consistent with the fact that the warming of recent decades is as large or larger for night-time than day-time periods, and is another inconsistency with any potential CRF contribution to recent warming. One possibility is that any CRF-mediated cloud effects roughly cancel between day and night. For cloud effects to act on climate (Earth’s surface temperature), one expects that they need to be persistent at least for some hours. However enhanced cloud formation during the day (cooling effect) that persist into the night will result in a night time warming effect (decreased radiation of surface warmth) and vice versa. Overall Harrison and Stephenson is an interesting paper with what looks like fine data. However it doesn’t negate the very strong evidence for a lack of CRF effect on the very marked warming of recent decades, and if we’re concerned about that, we should focus to rather more well-supported causal factors. Secondly, it doesn’t constitute a very significant case for a CRF-climate link, and in fact tends to dis-favour such a link, at least over time periods in the relatively recent past (since 1600) when there is a reasonably good record of solar outputs (as monitored by sunspot numbers). [***]M. Lockwood & C. Fröhlich (June 2008) Recent oppositely directed trends in solar climate forcings and the global mean surface air temperature. II. Different reconstructions of the total solar irradiance variation and dependence on response time scale Proc. Roy. Soc. 464, 1367-1385. M. Lockwood (June 2008) “Recent changes in solar outputs and the global mean surface temperature. III. Analysis of contributions to global mean air surface temperature rise” Proc. Roy. Soc. 464, 1387–1404.
131954. shawnhet at 05:38 AM on 2 May 2008
        Do cosmic rays cause clouds?
        Chris, A couple of points here regarding the significance argument. No one that I am aware of has challenged Harrison & Stevenson 2006 which found that "Across the UK, on days of high cosmic ray flux (above 3600×102neutron countsh−1, which occur 87% of the time on average) compared with low cosmic ray flux, (i) the chance of an overcast day increases by (19±4) %, and (ii) the diffuse fraction increases by (2±0.3) %. During sudden transient reductions in cosmic rays (e.g. Forbush events), simultaneous decreases occur in the diffuse fraction. The diffuse radiation changes are, therefore, unambiguously due to cosmic rays. Although the statistically significant nonlinear cosmic ray effect is small, it will have a considerably larger aggregate effect on longer timescale (e.g. centennial) climate variations when day-to-day variability averages out." Now, it seems to me that given the above, it is one thing to be skeptical of the significance of the CRF climate link, it is another to say that there is no evidence that it is significant. Cheers, :)
        Response: Actually, I know of two papers that cast doubt on Harrison's result on forbush decreases. One is Sloan's paper, the subject of this post. His paper actually has 3 sections - on latitude dependence, forbush decrease events and LCC lagging CRF. My plan was to do a separate post on each section. However, just over the last few weeks, another study was done on forbush decreases by Jón Egill Kristjánsson who presented his results at a recent AGU conference. He found a similar result to Sloan. I contacted Kristjánsson about the paper but it's still in review. So I'm mulling over whether to wait for the paper to be published before doing the post on forbush events and Harrison's paper. Or maybe I'll just go with Sloan for now. Stay tuned :-)
131955. Quietman at 03:05 AM on 2 May 2008
        Can animals and plants adapt to global warming?
        chris You are asking me to give an answer that that thus far has been unanswerable. I can only give you my philosophical view. For starters, my view of our part in extinctions is a natural one. We are animals struggling for survival. In our struggle we have made many mistakes and to correct them is the obvious thing to do. But because we are a part of nature the term "man made" warming is referring to our mistakes and not outside of nature. The current AGW is the point of contention. Will it cause extinction on its own. No, I do not feel that our errors alone are a cause but they certainly don't help. Should we save the polar bears, No. First, I don't believe that they need any help. Second, they are a competitor to us as a species, we eat the same food and occupy the same habitat. Our duty is to our species, not to a species in competition. The save the bears thing is an emotional issue, not a darwinian issue. We need to concentrate on helping species that are beneficial to us, regardless of the actual cause of their stress. As for the cyclic nature of the universe, that would take a lot more room than John has on this server. We need to stay on a point to point basis, like PDO and the Atlantic cycles, the vulcanism and gravitational pressure that drive them and the solar cycles, each has a place but not in this thread.
131956. Quietman at 02:25 AM on 2 May 2008
        Can animals and plants adapt to global warming?
        John In your comment to chris you mrntion a title change. I think that you chose the better title as AGW may make the event worse but did not start the event which has been going on for a very long time. We, as a species, have only barely survived this event and are in a diversification stage ourselves. My personal belief is that this event is nearing an end and we will be the winners if we get our act together.
131957. chris at 23:28 PM on 1 May 2008
        Can animals and plants adapt to global warming?
        Quietman, I'm going to answer each of your points sequentially: ["I do not disagree that there is a possibility of these extinctions. But I do feel that in most cases diversity must and will occur, just as descibed by Darwin, but that it will be new species that survive, not the parent species."] I think you're being over-theoretical here. If one dissociates oneself from extant reality and views our situation as an interested bystander, no doubt one can conclude that the present extinction period, will in time (we're talking many 100's of 1000's to millions of years), result in a rediversification of life on Earth. All very interersting from a Darwinian perspective no doubt. However if we are interested in our extant reality and that of our descendants over the next decades, 100's and even 1000's of years, then we might want to put those academic considerations aside and focus on the reality. And the reality is that continued habitat degradation exacerbated by continued global warming is going to produce an inpoverished biosphere. Since we're not disinterested bystanders, but are in fact an integral causal part of these processes, we might want to consider doing something to address the problem (which we are, as it happens, since there are many efforts underway to protect wilderness areas, and there are growing efforts to address the problems of man-made global warming). ["Re: "There's no such thing as an "extinction cycle"." That is not a fact. It has not been proven one way or the other. The Berkeley paper is a hypothesis, and if correct, we are in one now. The evidence so far is very good that we indeed are. Are you denying that there are climate cycles as well?"] Fair enough. However one has to be careful here. Let's say that the Berkeley paper [Rohde and Muller, Nature 434, 208 (2005] is correct. You say that means that (referring to extinction "cycles") "...we are in one now. The evidence so far is very good that we indeed are". But that is to take the passive attitude to ridiculous extremes. The natural world is not in the process of undergoing a large-scale extinction because of some ill-defined, uncharacterised "cycle" in which we find ourselves helplessly unlucky enough to find ourselves!. It is in the process of large-scale extinction because of large-scale habitat destruction and the other human practices described in Barry Brook's article at the top of this thread. We're part of it. Now are there extinction cycles? Perhaps there are but the evidence isn't very strong. It's possible that the extinction/diversity events only appear to follow a cycle, but aren't cyclic at all. After all there's rather good evidence that the end-Cretaceous extinction 65.5 million years ago (mya) was due to an extra-terrestrial impact perhaps supplemented by the massive tectonic events which formed the Deccan Traps in now-India. The extinctions at the Paleo-Eocene Thermal Maximum (55 mya) was likely due to the tectonic events (and massive release of methane) associated with opeining up of the North Atlantic plate boundary. The Triassic-Jurrasic extinction (201.6 mya) associates with the massive volcanic outpourings of the central Atlantic magmatic province.....The huge Permian-Triassic extinctions (252.5 mya) appear to coincide with the tectonic events resulting in the Serbiamn Traps formation....and so on. Are these events part of some huge cyclic phenonenon during Earth's history? It seems unlikely. The most "popular" notion of the origin of the 62 my "cycle" is long term cyclic variation of the cosmic ray flux (CRF). But how does that relate to tectonic events on Earth? It's difficult to ascribe any sort of connection. I suspect that the extinction/diversity cycles only appear to be "cyclic". However even if they truly are part of a grand cycle, that obviously doesn't account for the current extinctions. Is the world undergoing massive tectonic processes during the past 200 years? No. Are we being blasted by a massively enhanced CRF all of a sudden. No. We know what is causing the current extinction. It ain't some magical "cycle". It would be foolish to sit back passively and suggest such a thing... ["Are you denying that there are climate cycles as well"] Which "climate cycles"? There is an 11 year solar cycle. There seem to be cycles associated with ocean circulation. There are the climate cycles associated with the slow variations in the orbital properties of the Earth (Milankovitch cycles). But what other cycles are you considering? Again the same argument applies. Whether or not there are "climate cycles", we know that the current very marked warming of the last 30-odd years isn't due to any of the cycles that we know of. It's very likely to be due to man-made enhancement of the Earth's greenhouse effect. By suggesting that everything is "natural" (we're in a "natural extinction cycle"; we're in a "natural warming cycle") we might conveniently absolve ourself from any imperative to address these problems. In fact we know with a very high degree of probability that the current extinctions are not part of some "natural cycle" and the the current warming is not part of some "natural cycle". The evidence is overwhelming on the first and very strong on the second. Clearly if these were "natural" then the must have some explanation in terms of "natural phenomena". So what are these "natural phenomena"?
131958. frankbi at 16:38 PM on 1 May 2008
        Models are unreliable
        Wow Poptech, what a rousing, impassioned, statesman-like speech. Unfortunately, it contains no verifiable concrete facts.
131959. Elanc at 15:58 PM on 1 May 2008
        La Nina watch: March update
        What about this news bulletin from NASA which indicates that we may have a significant cooling effect for the next 20-30 years? La Nina and Pacific Decadal Oscillation Cool the Pacific http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=18012
131960. Quietman at 15:01 PM on 1 May 2008
        Can animals and plants adapt to global warming?
        chris I do not disagree that there is a possibility of these extinctions. But I do feel that in most cases diversity must and will occur, just as descibed by Darwin, but that it will be new species that survive, not the parent species. Re: "There's no such thing as an "extinction cycle"." That is not a fact. It has not been proven one way or the other. The Berkeley paper is a hypothesis, and if correct, we are in one now. The evidence so far is very good that we indeed are. Are you denying that there are climate cycles as well? I agree with your closing statement. We should indeed protect the environment to minimize stress on these animals, but that does not make it less interesting from an evolutionary standpoint. By the way, I am somewhat skeptical about the current causes of climate change. So from my point of view much of this is natural. But that is irrelevant to my statements here, as I am not advocating that we just let them die. So please do not be offended by my scientific curiosity.
131961. Quietman at 14:30 PM on 1 May 2008
        Can animals and plants adapt to global warming?
        Steve L I understand what you are saying, there is more than one definition. I database fossil species primarily so I look at living species from a evolutionary point of view. I see polar bears as speciation in progress, so calling them a species as far as legal terms go, I don't have an issue with and that is not why I used them. I used polar bears because everyone is somewhat familiar with them on an international level. Coyotes are not as well known but are another example of speciation in progress.
131962. chris at 09:52 AM on 1 May 2008
        Do cosmic rays cause clouds?
        shawnet, O.K. now perhaps we are talking past on another!. My very first post on this thread started: ["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?"]. When I state that most papers don't support the connection, I'm talking about (ii) namely the connection between CRF and climate. There is evidence that the CRF can influence cloud formation. Is this significant with respect to the Earth's surface temperature and climates? There's very little if any evidence in support of that idea. We know that the very marked warming of the last 30-odd years has occurred without a significant contribution from changes in solar outputs. Therefore the CRF has been largely irrelevant during that period. Svensmark has presented his evidence in support of that rather well-supported conclusion. Svensmark's ionization chamber experiments aren't particularly compelling with respect to this (CRF-clouds-climate), and a causal chain needs to address several questions: (i) are the nanometre size nuclei observed in the ionization chamber relevant for cloud nucleation in the real world? (ii) does any CRF-mediated cloud formation significantly alter the cloud cover in a climatically significant manner? After all there are many cloud nucleating species in our atmosphere (particularly in our modern world). Might any clouds produced by CRF be nucleated by other species anyway? (iii) Clouds have short lifetimes (few hours). The nucleation of clouds results in a lower water vapour concentration in that part of the atmosphere (unless or until the condensed water vapourises again). So a cloud that might subsequently have formed may not now do so. Thus the cloud cover in that particular region might be net-neutral averaged over a short period (say a daylight period) whether or not CRF-mediated cloud nucleation occurs... and so on. Note that this isn't quibbling. It is addressing the rather blatant facts that CRF hasn't contributed to the most significant global warming event of the entire Holocene, and the fact that there is no evidence for CRF-mediated cloud nucleating contributions to climate. Thus it is difficult not to be skeptical about the notion. Of course that doesn't mean that it doesn't exist (CRF-mediated cloud nucleating contributions to climate). It just means that there is no evidence for it..
131963. chris at 09:02 AM on 1 May 2008
        Can animals and plants adapt to global warming?
        Quietman, You can't separate adaptation from extinction in the context of global warming. If the title of the thread is "Can animals and plants adapt to global warming?" the answer must contain the probability that for many species the answer will be no. No means extinction. There's rather clear from Barry Brook's analysis and from what we have observed already in relation to habitat destruction and impoverishment. There's no such thing as an "extinction cycle". There are extinction events that have causes (most likely climatic changes in the broadest sense as you indicate). So the Holocene extinction is not part of some grand "cycle", and describing it as such can suggest the notion that it's either inevitable or nothing of much concern (after all it's just another part of the "extinction cycle"!) In fact it's an extinction that relates to man-made destruction and impoverishments of habitats, and it's likely to be exacerbated in a warming world. It is an issue that we can choose to address or not. I don't see your point about diversification in relation to polar and grizzly bears. Of course species have diversified in the past (polar bears likely split from the ancestral species from a couple of 100,000 years ago). The past has seen a glorious diversification of species to give us the richness of the natural world which man-kind has already rather significantly reduced especially during the last couple of centuries. If one considers the fate of bears now and in the future it's not a rosy one. For example, the possibility that polar bears become extinct as their habitat disappears in a warming world is a significant one. Unless wilderness areas are maintained there won't be any bears at all, since bears and mankind are incompatible outside of zoo's and circus's...considering bears overall, extinction is a rather more likely future than diversification... That's really the point. In the deep past speciation/diversification occurred with speciation events likely taking 100's of 1000's of years (much like the polar bear speciation/diversification). Every so often massive climate change (resulting from extraterrestrial impacts or from massive tectonic events, for example) resulted in very widespread extinctions. These events weren't associated with diversification since, in general, most of the species of interest were unable to adapt. They went extinct without diversification. It was only following the recovery to more stable environments that the evolutionary process allowed the recovery of an impoverished post-cataclysmic biosphere, and this recovery, which was associated with rather widespread speciation/diversification as habitats were repopulated took many millions of years. So we need to be clear about where we are. Yes we have seen some speciation/diversification during the Holocene (the evolution of freshwater seals in Finland is a better example, since this is a truly post-glacial event), but we've seen far more extinction. The combination of continued habitat destruction combined with a very rapid warming is very likely to see this trend accelerating into the future. Yes there will be many species that survive and a few may diversify in response to habitat/climatic changes in the coming 100's and 1000's of years. But on the whole the biosphere will continue to become impoverished. If we have 500,000 species of "interesting animals" (say the size of a child's fist and larger!), and we watch 200,000 of these disappear (unable to adapt = extinct), while 100 (say) undergo diversification to new species, I think we would agree that the richness and diversity of the biosphere has become degraded. In recognising where we are, we have the ability to address these issues, since we're very much part of it all. We're not bystanders observing some inevitable "extinction cycle" and 'though we might be enthused by the possibility of P.E.-type diversification within those species that are able to adapt to an impoverished natural world, I would consider that future generations would be rather more enthused by the possibility that we might now be taking steps to minimize the impoverishment of the natural world which they will inherit.
131964. Steve L at 08:04 AM on 1 May 2008
        Can animals and plants adapt to global warming?
        Sorry, I should apologize for the US-centric view assumed in the above comment. I refer there to the ESA of the United States and a decision on polar bears to be made by the US gov't.
131965. Steve L at 08:01 AM on 1 May 2008
        Can animals and plants adapt to global warming?
        Quietman, I have an interest in evolution too and work as a biologist studying salmonids. I say that because I think I disagree with large portions of what you've written, and I don't want you to think it's because of a lack of evolutionary perspective on my part. One place we could start is with polar vs grizzly bears. I pick this one because it's topical wrt an impending decision re ESA listing. (Is that why you chose that example?) First argument: Ursus arctos vs Ursus maritimus -- they are described as distinct species; hybridization is not enough to say they are only subspecies unless you apply a strict "biological species concept" (Mayr). You can search for many articles describing the difficulties in applying that concept. You might like to read this paper, too (I'm a coauthor): http://tinyurl.com/5fdax5 Second argument: under the ESA, distinct population segments can be listed as species. That is, the legal definition of species does not follow the biological species concept.
131966. Quietman at 06:15 AM on 1 May 2008
        Can animals and plants adapt to global warming?
        Re: "we're not going to see diversification" I have to disagree on this point. We have already seen diversification within the Holocene. The same Polar/Grizzly Bear exaample serves. It is one species that we did not recognize as one because they were/are in the process of speciation (Darwin's mutation and variation in isolation). Hybridization is already showing up as their habitats begin to overlap. Hybridization can lead to a new subspecies as well. If subsequently isolated speciation would occur eventually as well. The comparison of the geologically short time that hominids have existed can not be validly compared to the thousands of years prior. If you want to use the past century, it needs to be compared to a similar sized slice of the past. This is a common error when trying to compare trends. The likelyhood of the slope of a single century resembling that of an epoch is extremely low. Its like apples and oranges, they both may be round but there the similarity ends.
131967. frankbi at 04:55 AM on 1 May 2008
        There is no consensus
        Robert S: Well, I couldn't find any concrete mention of any figures above 19... only some mentions of climate inactivists claiming there were "hundreds" of scientists there. Given that there were ~500 people in total, I wonder why they couldn't be more specific. In the meantime, Heartland Institute included a list of climate skeptic "co-authors" which included Mann, Rahmstorf, Keeling, and other well-known global warming theory _proponents_. And many scientists are angry about this: http://tinyurl.com/6zjxy4
131968. shawnhet at 04:05 AM on 1 May 2008
        Do cosmic rays cause clouds?
        "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." I think it would be much more productive to simply list the scientific papers that demonstrate the CRF-cloudiness connection that you keep referring to. I am familiar with Sloan's(obviously) and Rahmstorf's, but I don't think either of these is all that good a critique. Do you have any others in mind? There are some results out there that are very difficult to dismiss (for instance Harrison and Stevenson 2006 and Svensmark's 2007 experiments) to uncritically accept the idea that most of the evidence is against such a link. Cheers, :)
131969. Quietman at 03:13 AM on 1 May 2008
        Can animals and plants adapt to global warming?
        Chris The comment is about how the species will adapt as was specified in the title to the blog. So adaptation, not extinction is the subject (no offense meant). My remark about it being interesting is simply that I have studied paleontology, extinction and evolution for over 40 years as a hobby so I appreciate a Blog on my favorite subject. P.E. was actually a Darwinian conceot that he mentioned in "On the Origin of Species". Both Darwin (in his writings) and Gould (in TV intervies) spoke about environmental pressures causing sudden jumps in evolution, and that is the part of PE that I refer to. The most recent study of extinction cycles is out of USC Berkely and they found an average rate of 62 million years. This should place us within the error bounds of an extinction cycle right now which seems to have begun about 10,000 years ago, the cause of which is climate change, as is the end cause of every major extinction regardless of the trigger mechanism. Extinction of a species happens constantly, its natural and the species is replaced by something else. An example is the polar bear, not a true species by definition, but a variation of the grissly bear. The Species is not endangered but a variation or subspecies is. That is how evolution works, although the polar bear is not actually in danger of extinction and the likely result will be hybrisization. What I found interesting is not the extinction but the new species cropping up in the more tropical climates. especially SE Asia and South America. They are new discoveries but are they small populations because of an extinction or because they are brand new species of the Holocene? I wait with anticipation for the DNA results. None of this is heartless or cruel, its just how nature works.
        Response: The article is about extinction. The premise is "will animals adapt or become extinct". In fact, the original title was "will global warming cause a mass extinction event?" but I changed it. Now wondering if I was mistaken.
131970. chris at 23:16 PM on 30 April 2008
        Can animals and plants adapt to global warming?
        Quietman, on your description of Punctuated Equilibrium (P.E.): ["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."] I'm not sure that's a good description of Punctuated Equilibrium for several reasons, and you seem to be (correct me if I'm wrong) pursuing the notion that man-made extinctions (present and future), are a rather jolly wheeze from the point of view of interesting potential observations (your first post seems to indicate that). Here's some of the problems: 1. It's unlikely that mutations occur more rapidly under stressed conditions, if by "mutations" you mean the DNA-level mutations that underpin the evolutionary process. 2. Eldredge and Gould, as far as I remember, didn't specify "stressed conditions" in relation to P.E. The main mechanistic element of P.E. is the existence of sub-populations of species, either at the physical margins of the population range, or completely isolated from the main species population. In these instances mutations don't occur more rapidly. However mutations are not diluted through the main species pool, and so may be maintained in the sub-population. In fact speciation within P.E. might occur by genetic drift. The major element is population-isolation rather than population-stress. 3. P.E. is neutral with respect to diversification. P.E. scenarios resulting in increased diversification can be formulated (there's evidence for these) as can P.E. scenarios resulting in none, or even decreased diversification (there's evidence for these too) although the latter would involve more widespread consideration of a particular ecosystem. The latter is the concern with respect to global warming within a world with already fragmented and denuded ecosystems as indicated in the excellent summary by Barry Brook at the top of this section. Clearly over the significant human-scale term (10's, 100's, 1000's of years) exctinctions are going to continue to increase, so (whatever the joys of potentially "observing" P.E. on the hoof!), we're not going to see diversification. Secondly, it's not obvious that we're likely to have enhanced opportunities for observing P.E. on the hoof anyway. In fact the opposite is far more likely. Never mind the fact that speciation events require many generations, and so we're unlikely to see these in animals on human timescales anyway. In a world of fragmented and denuded ecosystems there are likely to be less speciation events to observe. After all we can already observe incipient speciation under P.E. type scenarios (e.g. "ring species"), and it's questionable whether things are going to be more interesting in that respect in a world with even higher levels of species extinction.
131971. 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.
131972. 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?
131973. 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.
131974. 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…
131975. 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.
131976. 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.
131977. 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.
131978. 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.
131979. 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.
131980. 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.
131981. 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.
131982. 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.
131983. 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.
131984. 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.
131985. 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...
131986. 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...
131987. 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.
131988. 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...
131989. 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.
131990. 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, :)
131991. 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!
131992. 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
131993. 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/...
131994. 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
131995. 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, :)
131996. 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.
131997. 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.
131998. 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.
131999. 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.
132000. 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.

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