| Revision as of 10:08, 21 March 2006 editWilliam M. Connolley (talk | contribs)Autopatrolled, Extended confirmed users, Pending changes reviewers, Rollbackers66,015 edits →1470?: ah← Previous edit | Latest revision as of 16:41, 27 December 2024 edit undoCewbot (talk | contribs)Bots7,341,261 editsm Maintain {{WPBS}}: 2 WikiProject templates. (Fix Category:WikiProject banners with redundant class parameter)Tag: Talk banner shell conversion | ||
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| Thanks for adding some actual ] to this article, William! | |||
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| == Chart looks rather out of date == | |||
| :The rate of reactions is sufficiently constant that the amount of ] emitted at the surface does not change much. The variations in total output are so slight (as a percentage of total output) that they remained at or below the threshold of detectability until the satellite era, although the small fraction in ultra-violet wavelengths varies by a few percent. Total solar output is now measured to vary (over the last two 11-year sunspot cycles) by less that 0.1% . | |||
| The chart needs updating - as it ends in 2006 - missing the latest solar cycle. | |||
| I'm so tired of ignorant hacks (like me ;-) just pasting in poorly-reworded summaries of popular articles or propagandistic advocacy pieces!! --] 14:29, 10 Aug 2004 (UTC) | |||
| ] (]) 14:46, 7 April 2014 (UTC) | |||
| == Historical perspective == | |||
| (] 21:40, 10 Aug 2004 (UTC)) Hey, you said it :-) Anyway: re Spencer Weart: firstly I don't think this belongs here, at the front (I would move it but can't at the moment). Connection to sfc T is the only reason you (or I, to be fair) care about solar var, but its not its primary characteristic. Secondly, what you quote is *history* from 1975! Wiki should be presenting the present-day opinion. Oh, and I changed the quote style at bit. | |||
| Is this quote really helpful? First off, it talks about weather prediction, not climate. The quote itself is ambiguous, open to interpretation as either: "history has shown time and again that it is pseudo-science" or as "in those days it was seen as pseudo-science, but now we have a better understanding". The intro of the source text would be a better choice imo: | |||
| :History is interesting. If someone makes predictions and they keep turning out right, I'm going to spend more of my valuable time studying what _he_ says, rather than someone whose predictions mostly turn out wrong. So ] who was moaning about global cooling less than 30 years ago, and ] with predictions of scarcity and starvation, earn less credibility in my book. And when they start endorsing the "Chicken Little" of the moment, ], it makes me want to have someone doublecheck Mann's research. --] 14:33, 13 Aug 2004 (UTC) | |||
| :''Since it is the Sun's energy that drives the weather system, scientists naturally wondered whether they might connect climate changes with solar variations. Yet the Sun seemed to be stable over the timescale of human civilization. Attempts to discover cyclic variations in weather and connect them with the 11-year sunspot cycle, or other possible solar cycles ranging up to a few centuries long, gave results that were ambiguous at best. These attempts got a well-deserved bad reputation. Jack Eddy overcame this with a 1976 study that demonstrated that irregular variations in solar surface activity, a few centuries long, were connected with major climate shifts. The mechanism was uncertain, but plausible candidates emerged. '' ] (]) 20:18, 20 October 2013 (UTC) | |||
| :: (] 15:20, 13 Aug 2004 (UTC)) SS is often misrepresented. Try www.wmconnolley.org.uk/sci/iceage if you haven't before. | |||
| :The article itself is rife with such conflicts. I don't expect an easy resolution. ] (]) 12:50, 7 November 2013 (UTC) | |||
| :: Can't see the relevance of Ehrlich | |||
| == Solar constant == | |||
| :: Calling Mann a chicken little is a grosss pointless insult and you should be ashamed - you wouldn't call anyone on wiki that. | |||
| The article states that "The amount of solar radiation received at the outer limits of Earth's atmosphere averages 1366 W/m<sup>2</sup>." Yet the Misplaced Pages article on the ] gives the value of 1361 W/m<sup>2</sup>. Can anyone explain the discrepancy? Thanks. ] (]) 20:11, 27 March 2014 (UTC) | |||
| ::Lastly: yes history is interesting. In various places though you've been putting in history (eg 1990 ipcc) as though it were representative of current opinion. History goes in a section marked history. | |||
| :The lower estimate is more recent. Don't know if it is controversial. See ]. ] (]) 06:06, 16 July 2015 (UTC) | |||
| ::* I hacked in a poorly worded summary of the history of the field, instead of the cryptic mention by Weart of solar+aerosol study. Weart's quote is in his already-linked-to "Discovery of Global Warming" page. I relabeled the entry for that link. Oh, and '''Uncle Ed''', thanks for having the doublecheck done. (] 19:49, 21 Feb 2005 (UTC)) | |||
| ::I moved the order of these around slightly, to put the solar constant before the variation in solar constant, but didn't change the actual number without a canonical reference. Different sources do use slightly different totals. Several links were redirects to "]", so I consolidated these to just one place. ] (]) 17:34, 19 July 2015 (UTC) | |||
| == Referencing == | |||
| == Predictions based on patterns == | |||
| I don't understand what's going on with the recent spate of reversions - surely references at end using templates are better than inline refs? ] 10:52, 2 October 2005 (UTC) | |||
| This section is a bit rubbish. Firstly, it "predicts" the 2010 peak, and no-one (including me!) has bothered update it for whatever happened. Secondly, its almost all about "predicting" climate (has it been copied in from elsewhere) not predicting the cycles, so it belongs under the climate heading ] (]) 08:15, 16 February 2015 (UTC) | |||
| == Cosmic ray claim == | |||
| ::I'm not taking sides unilaterally. It's Misplaced Pages style guidelines: see ]. ] 16:43, 2 October 2005 (UTC) | |||
| Why is the stuff on cosmic rays in there? It doesn't apply to solar variation in any way. ] (]) 16:41, 15 July 2015 (UTC) | |||
| :I'm not sure I understand the question. The sun's magnetic field deflects galactic cosmic rays. Thus, cosmic rays decrease with higher solar actitity. So this is related to solar variation. | |||
| I don't know the status of the footnoting debate, but the edit I just reverted did not make a footnote - just put the URL inline rather than as #1. I see the edit comment ''rv WMC's destructive wiki edit'' as inflamatory and uncalled for. If SEW wants to use an as yet poorly defined footnote style, then make the ref in question #1 in the footnote list. I feel inline references (with a list of refs at the end) preferable as well as much easier to use and manage by future editors to the page. I have experimented with the style SEW wants to use here in other articles and found it cumbersome. Let's keep the edit comments civil, please. ] 20:57, 2 October 2005 (UTC) | |||
| :However, if you're just saying that there's too much on this subject for the article -- well, ok, maybe there is, and possibly it should be compressed and put into a single subsection, instead of spread over several. | |||
| :--by the way, you changed the term "galactic cosmic rays" to just "cosmic rays" in several places. I'm going to change those back-- the more generic term "cosmic rays" can also refer to solar proton events, which of course increase with solar activity. ] (]) 20:37, 16 July 2015 (UTC) | |||
| == Restructure proposal == | |||
| : WMC's edit did use destructive wiki code which goes against policy and guidelines. (] 02:32, 16 October 2005 (UTC)) | |||
| {{tlu|User:Lfstevens/sandbox}} | |||
| : I'm not saying that inline references are bad - they're better than nothing. If you want to use them, please ''do not make the entire url appear'' - shrink them into, say, . ] 23:15, 2 October 2005 (UTC) | |||
| === Comments === | |||
| ::My point exactly. And a weakness in the footnote3 system as any innocent (or otherwise) insertion of a good inline reference messes up the footnote3 numbering - quite a serious flaw it would seem - makes for a high maintenance problem. As for SEW's last ''revert'', why not make the link #1 in the refs - it is a valid and used reference? Has the use of footnote3 been discussed and agreed on here - or is it just a ''bold'' decision by one editor - why not discuss? ] 00:49, 3 October 2005 (UTC) | |||
| * | |||
| : Let's come to some sort of consensus then. I suggest using footnote3 ''consistently'' for just about everything since most of the article already uses it anyway. ] 01:13, 3 October 2005 (UTC) | |||
| * | |||
| :: The footnote3 system is cumbrous and unmaintainable. Adding a new ref in destroys it. It is not acceptable to forbid adding any new style links into the page, as SEW is trying to do. Wiki is supposed to be *simple* and easy to use, and should not force you into over-elaboration. ] 08:41, 3 October 2005 (UTC). | |||
| ::: There is a recommended style for inline links, which you chose to not follow. I converted the inline links to use more complete Footnote3 citations. (] 17:33, 3 October 2005 (UTC)) | |||
| :::: Hardly anyone follows it, for the obvious reasons, mentioned above. ] 20:24, 3 October 2005 (UTC). | |||
| ::: There is a reason why they exist; no one wants to make it more difficult. Sometimes books or other offline resources are used as references; e.g. "Henrik Svensmark (1998). Influence of Cosmic Rays on Earth's Climate. Physical Review Letters 81 (22): 5027-5030". This is not possible without footnoting. Using the footnoting system is not difficult - sure, it takes two edits instead of one, but it's not that much more difficult. Also, if you ever want this article to be featured, it will need to use footnoting. If you find the current mish-mash of styles annoying, wait until the weekend and i'll sort it out. ] 08:58, 3 October 2005 (UTC) | |||
| ::::Sorry, I will oppose featured article status, that usually makes an article worse.--] 09:19, 3 October 2005 (UTC) | |||
| ::::: What?? I don't understand you guys. ] 10:04, 3 October 2005 (UTC) | |||
| We're not talking about books. These are inline refs to web pages. Introducing a cumbrous system that makes it impossible to add new refs without re-numbering all the exising ones is unmaintainable. Your point about FA is bizarre: if true, its a huge hole in the FA system, but I suspect you're simply wrong. FA need good refs, not to use the broken fn3 system. ] 15:11, 3 October 2005 (UTC). | |||
| : Then how do you suggest we reference offline material? (Note that there is at least one offline reference in the existing footnotes.) Inline them too? Ridiculous. ] 15:56, 3 October 2005 (UTC) | |||
| :: In the few cases where we're referencing offline material, then I guess you have to fall back on the unsatisfactory footnote style. But the vast majority are to online material so we don't have to use it. ] 20:06, 3 October 2005 (UTC). | |||
| ::: So all that an online material citation requires is a URL, with no title nor author information? Online material such as , which only states that I have to log in. Until I log in I don't know if it is worth paying to see whatever it is. Assuming, of course, that it is not a dead link. (] 20:47, 3 October 2005 (UTC)) | |||
| :::: "something must be done. this is something. therefore it must be done". Its obvious nonsense, and so is trying to use such a cumberous system. If we had a nice system that was easy to use and dealt well with adding new ones, then great. But we haven't got that. ] 21:00, 3 October 2005 (UTC). | |||
| ::::: Footnoting is generally problematic on wikipedia; there is an alternative system (in use at eg ]) which allows mixing inline and footnotes without too much confusion. Not ideal, but less bad than some of the other footnoting systems. ] 21:35, 3 October 2005 (UTC) | |||
| ::::::I just took a look-see at that article and the current problem here would be solved if that ''have it both ways'' approach were adopted here. Does it have a name - like the footnote3 thingy? In my earlier experimenting w/fn3 I was dissapointed by the potential for the kind of disruptions we see here - one in line link messes it up. ] 22:44, 3 October 2005 (UTC) | |||
| ::::::: This was the reason I created ] a while ago. But I notice now that it seems that approach has been (sort of) integrated into footnote3, so probably better to look at ] for the possibilities there. Ref_num looks like it does the same job. ] 06:59, 4 October 2005 (UTC) | |||
| ::::: I agree that footnoting is a problem; some of the discussion pages in fact talk of building it into the mediawiki software in the future. In the meantime, we need to come to a satisfactory resolution. I don't mind the style they have at the ] - it's not ideal as the numbers need manual editing which is always undesirable. However, SEWilco has a point - web pages are just like offline references in a way - if you're writing an essay, wouldn't you put in author/title/retrieval date, especially for these newish areas of science? I'd vouch for the footnote3 system because, even though there is currently no concensus, the discussion there notes that it is future-proof - any future system should be able to read it in and convert it. ] 23:46, 3 October 2005 (UTC) | |||
| : Future proof is wonderful. But the fn3 system isn't present-proof (to repeat the point you've missed: its too cumbersome; its unmaintainable). Look around the ] type articles - there are lots and lots of inline links, and the *only* fn3 links are those put in by SEW because its his pet system. ] 09:21, 4 October 2005 (UTC). | |||
| :: How exactly is <nowiki>{{ref|blah}}</nowiki> and then <nowiki>{{note|blah}}</nowiki> at the end so much more difficult? The main problem here is that there are two starkly opposing sides and this edit war is going to go on until the sun dies. A compromise, somewhere in between, is to use the <nowiki>{{NamedNote}}</nowiki> system, but you don't seem to like that either. ] 09:59, 4 October 2005 (UTC) | |||
| ::: If its so easy, why are you making edit commments praising the "lot of work" that you think SEW did? Please at least try to be consistent. The point is that adding refs using is easy. Its also easy to use them as a reader: click on them and you're there. The fn3 system is hard work (even you admit that) and takes two clicks to get to. Its silly. Also somewhat unexplained is your sudden interest in solar var. ] 10:39, 4 October 2005 (UTC). | |||
| :::: You misunderstand me. I've never said that fn3 is hard work - however, ''converting an entire page with tens of them is work to be congratulated''. In some cases, it's less work - I can click on it, see the title and decide whether to proceed. My sudden interest in solar variation? What does that have to do with you? For the record, I am an undergraduate who has done physics so I like reading this kind of stuff; I came here via global warming articles. ] 12:37, 4 October 2005 (UTC) | |||
| :::: Footnote3 links function despite the mismatching numbers caused by careless or destructive editors. The more complete citation information which tends to be used in references is more encyclopedic and robust than a bare inline URL. The numbering problems are a side effect of current Mediawiki limitations. (] 15:48, 4 October 2005 (UTC)) | |||
| === Detailed citations policy === | |||
| ] policy prefer more detailed source references over less detailed. ] has been destroying more detailed source entries due to being "icky". Which policy covers "icky"? (] 02:32, 16 October 2005 (UTC)) | |||
| : I guess some people are just allergic to references like others are to hayfever. If there continues to be a problem, you might like to consider ], but we'll see. ] 07:45, 16 October 2005 (UTC) | |||
| :: You are trying to use a variety of inapplicable policies to bludgeon in your pet project, ignoring their problems, and the difficulty of working with these things (which is presumably why you have to litter the page with instructions on using them). ] 10:04, 16 October 2005 (UTC). | |||
| == Table of events == | |||
| The table of events is currently: | |||
| Solar activity events and approximate dates Event Start End | |||
| Oort minimum 1040 1080 | |||
| Medieval maximum (see Medieval Warm Period) 1100 1250 | |||
| Wolf minimum 1280 1350 | |||
| Spörer Minimum 1450 1550 | |||
| Maunder Minimum 1645 1715 | |||
| Dalton Minimum 1790 1820 | |||
| I'm curious about the first two (and perhaps the third). They can't be read from the graphs on the page and I can't see any other source. Where is the info from? The Oort min is smack in the middle of the MWP period, incidentally. ] 16:06, 31 October 2005 (UTC). | |||
| == Other factors == | |||
| What should be in the global warming / climate change section is a link to ]. That and the related ] and ] need a bit of numbers disambiguation on the variation in how much Earth's axial tilt changes. | |||
| Climate change is driven by BOTH variations in solar output and the continously varying tilt of Earth's axis, which at present is decreasing. Think about the effect that has on the amount of surface area that's in constant darkness from 24 hours to six months per year, and how that affects the net heat loss. | |||
| : There already is a section about Milankovitch cycle variations. (] 15:19, 11 December 2005 (UTC)) | |||
| == gw section == | |||
| The entire GW section is poor, presenting marginal research with far too much priority. The Mainstream view isn't presented at all! | |||
| I cut out all the S+V stuff. It looks like it wsa put in by people who hadn't even read the papers. So I cu: | |||
| : ''In 2003, Shaviv and Veizer compared a temperature reconstruction of the last 500 million years to expected changes in cosmic ray flux as the ] moves around the ]. They concluded that, at least over very long time scales, cosmic ray variations had a much larger impact on climate than other processes (such as ] changes) {{ref|www.envirotruth.org.94}}. Since, as described above, cosmic rays are also affected solar variations, their work may imply a larger role for solar variability in recent climate change than has previously been appreciated. Also, by looking at the temperature changes not ascribed to cosmic rays, they estimated that the climate response to doubling CO<sub>2</sub> is only about 0.75 °C as compared to the 1.5-4.5 °C reported by the IPCC {{ref|www.grida.no.95}}. However, long-term processes occurring over millions of years may make it impossible to interpret of Shaviv & Veizer's results over the short time scales relevant to recent warming. {{ref|www.soest.hawaii.edu.96}}.'' | |||
| Firstly, most of this has little to do with GW. Secondly its all marginal. Thirdly ''Also, by looking at the temperature changes not ascribed to cosmic rays, they estimated that the climate response to doubling CO<sub>2</sub> is only about 0.75 °C'' doesn't seem to be supported by the paper: what it *does* say is ''In summary, we find that with none of the CO2 reconstructions can the doubling effect of CO2 on low-latitude sea temperatures be larger than ~1.9 °C...'' which is somewhat different, no? And since global ch is larger than tropical, what they find is entirely *con*sistent with IPCC. Fourth its not clear than such far-past stuff (different continents etc) is terribly relevant. | |||
| I also took out: | |||
| : In 2005, Shaviv extended the analysis to several different time scales including historical 11 year solar cycle data, and concludes that solar activity accounts for 0.47 +- 0.19 degrees C (almost two-thirds) of the 20th century warming.'' | |||
| This is a bit better, but still misrepresents the paper. ] 17:38, 4 February 2006 (UTC). | |||
| :It was Singer that provided the translation of the low latitude figure to a global approximation here. Probably to make Shaviv's contrasting of his results with the 1.5-5.5 figure equivilent. How is the second paper marginal or misrepresented, or not relevant to global warming? The past stuff is relevant because it is data, the second paper makes it more relevant by showing that shorter time scales confirm the longer, thus making them mutually consistent and confirming, reducing concerns about the time scale differences.--] 18:11, 4 February 2006 (UTC) | |||
| :: Ah well, if it was Singer, that explains why it was junk - what else would you expect? S+V is all marginal - in the sense of being way-out-on-a-wing-by-themselves. But you won't be able to hear that. ] 10:18, 7 February 2006 (UTC). | |||
| == Graphics == | |||
| There were some poor quality charts, often reszed screenshots from PDFs. I've tried to, where possible, collect the relevant raw data from publically available sources and reproduce the graphs. Please feel free to revert if they aren't of appropriate quality. I do have some issues with the Hallstadtzeit cycle chart - once I detrended the data I still didn't get anything much akin to the claimed 2000 year cycle - there are some general periodic trends but they are far from clear as the caption (which I didn't change significantly) states. I also have some issues with the Carbon/Sunspot graph. There simply doesn't appear to be any really significant correlation even with the claimed 20 to 60 year delay. What am I missing? ] 03:52, 7 February 2006 (UTC) | |||
| :Some points: | |||
| :#If you are creating a replica image to replace one of low quality, it is a good idea to either include a link to the previous figure in the image description or to upload it with the same name so that the new figure automatically replaces the old (of course this is only possible if the same image format is used). If you do upload a new version over the old, the old version will be available in the file history section of the image description. | |||
| :#I would suggest using rather than INTCAL98, and note that the final point is not real data but some sort of end of record place holder. Since the invention of nuclear weapons, carbon-14 has been contaminated by man-made sources, which is why those data end circa 1950. | |||
| :#I am going to revert the Hallstadt cycle plot, since your figure is qualitatively different than the published result and I don't know why. If I had to make a guess, I would suggest they used a band pass filter whereas your figure suggests some sort of moving average or polynomial fit. | |||
| :#It's not a 20-60 year delay exactly, the residence time of carbon in the atmosphere is several decades, which causes terrestrial records to average over the short-term variability in production. So in essence, one is really only trying to say that the broad wiggles in carbon variation match the large scale changes in solar activity. As an intellectual exercise, one could try taking a moving exponential average of the sunspot activity with a multi-decadal time constant and seeing how well they agree. However, I would not generally encourage you to add such an average to the figure. | |||
| :] 04:58, 7 February 2006 (UTC) | |||
| == 1470? == | |||
| AFAIK the 1470 year cycle (Braun?) is only proposed, not an observed cycle. And why was the 2.3kyr cycle removed? Also the periodicity of D-O events is not by any means certain: controversial would be better ] 13:08, 19 March 2006 (UTC) | |||
| :Sorry, didn't mean to remove the 2.3kyr cycle. The 1470 year cycle is the same as the 1500 year DO periodicity. The Braun paper published in Nature makes the case that the actual periodicity is 1470. Of course since the identifying events usually involve the flipping of modes, it isn't 1470 like clockwork, but they sometimes flip early and sometimes late, but the 1470 can be seen as the attractor. Braun confirmed via modeling that the shorter cycles reinforce at this 1470 year period.--] 13:57, 19 March 2006 (UTC) | |||
| :: And are you claiming that the 1500/1470 y cycle is actually observed in solar output or anything like that? And please stop talking abpuot D-O "periodicity" as if it were settled fact: it isn't ] 15:47, 19 March 2006 (UTC) | |||
| :::It is a theory that is supported in the literature due to evidence seen in the climate and solar output proxies, and the citation from the recent Nature article is further support for that theory. I wasn't aware that the cycles already cited were factual and not theorectical. There is probably very few of the cycles have actually been observed for more than a few cycles beyond the 22 year cycle. The Nature article is a good place to start, since its references will lead you to other published support. In GW you have supported having climate model predictions in the article (I support that too), despite their not being settled fact, why are you applying a different standard here? This latest article is climate model based confirmation of this solar cycle mechanism for the increasing body of evidence for this periodicity.--] 05:57, 20 March 2006 (UTC) | |||
| :::If you don't have access to the full text of nature, perhaps you have access to this editorial summary. I think these like the abstracts are available free.--] 06:40, 20 March 2006 (UTC) | |||
| :::Here I quote the last two paragraphs of the article: | |||
| ::::''"A key aspect of our concept is that the events are triggered by very sharp peaks in the forcing, with duration of only decades. This can explain the puzzling regularity in the timing of DO events in the Greenland data, which were reported to deviate by no more than ,10% from exact multiples of 1,470 years15. If the events were triggered by broad peaks (for example by some sinusoidal-like forcing cycle of a 1,470-year period), much larger deviations from exact timing would be expected in the ‘noisy’ climate system. Hence, the exact timing of the more recent DO events (ages between 10,000 and 50,000 years) is a strong observational indication that they are synchronized by shorter cycles."'' | |||
| ::::''"We have demonstrated that a coupled ocean–atmosphere climate model can reproduce DO events with a robust spacing of 1,470 years when forced by the superposition of two freshwater cycles with much shorter periods near 87 and 210 years. A frequency of 1,470 years is therefore not found in the forcing; it is found only in the model response. We illustrated that this frequency conversion between forcing and response is a plausible consequence of highly nonlinear dynamics inherent in the simulated DO events. Our results indicate that the observed 1,470-year climate cycle could have originated from solar variability despite the lack of a 1,470-year spectral contribution in records of solar activity.Moreover, the 1,470-year climate response in the simulation is restricted to glacial climate and cannot be excited for substantially different (such as Holocene) boundary conditions; for these, the model response shows the frequencies of the applied forcing (,86.5 and 210 years), as also documented in various climate archives22,23,30. Thus, our mechanism for the glacial ,1,470-year climate cycle is also consistent with the lack of a clear and pronounced 1,470-year cycle in Holocene climate archives."'' | |||
| :::--] 07:17, 20 March 2006 (UTC) | |||
| :::'''Subscription not needed!!''' The paper itself is available online.--] 07:37, 20 March 2006 (UTC) | |||
| :::Here is a quote from an independent 1994 extrapolation based only on the current superposition of these two cycles ''" Extrapolation into the future of two cycles evident in the 14 C record, at 208 years (the Suess cycle) and 88 years (the Gleissberg cycle), suggests that the increasing solar activity that has followed the Maunder Minimum may continue into the early twenty-first century (Damon and Sonett, 1991), with a decline commencing around 2040. But extrapolation of these cycles into the future and prediction of solar effects is a highly questionable procedure, given our lack of knowledge of the fundamental processes involved (see Chapter 6). "'' Solar Influences on Global Change (1994) Commission on Geosciences, Environment and Resources --] 07:47, 20 March 2006 (UTC) | |||
| OK, well first off lets quote from your quote: ''Moreover, the 1,470-year climate response in the simulation is restricted to glacial climate and cannot be excited for substantially different (such as Holocene) boundary conditions; for these, the model response shows the frequencies of the applied forcing (,86.5 and 210 years), as also documented in various climate archives22,23,30. '' See how that effectively rubbishes Singers 1500 y stuff? | |||
| Now, we also have from the paper: ''But whereas pronounced solar cycles of ,87 and ,210 years are well known8–12, a ,1,470-year solar cycle has not been detected8.'' This means that whatever the virtues of this stuff, we *should not* be listing a 1470y solar cycle in "solar variation" - because even this paper admits its not there. | |||
| And lastly, I see you've totally ignored my ''And please stop talking about D-O "periodicity" as if it were settled fact: it isn't'', which is irritating. Its Rahmstorfs theory mostly. He's a good chap (of course) but that doesn't mean we take his word as gospel (as you would no doubt say were I to paste in some of his opinions on GW as fact). | |||
| ] 12:45, 20 March 2006 (UTC). | |||
| :I have totally ignored your please talk stopping about D-O periodicity. The peer reviewed paper in Nature had no problem talking about it: ''"The onset of successive Dansgaard–Oeschger (DO) events, as documented in Greenland ice-cores1,2 for example, is typically spaced by ,1,470 years or integer multiples thereof13,14. Because deviations from this cyclicity are small, often less than 100–200 years15, external forcing (solar or orbital) was suggested to trigger DO events6,15,16."'' I don't think "periodicity" is that far off from "cyclicity" but I can use the latter word if you prefer. | |||
| :The statement you reference does not rubbish Singers 1500 year stuff. The periodicity in the climate response is marked in the glacial record because of mode changes in the climate. The fact that during interglacials the mode changes don't occur, does not mean the superposition of the shorter solar cycles resulting in peaks of forcing at every 1470 years does not occur. It only means that the mode change does not occur. But the 87 and 210 year cycles are well established even in the Holocene climate, so their superposition will also exist in the Holocene. Perhaps it is non-traditional to list 1470 among the solar cycles, because it is a multiple of the smaller cycles, but it exists just as multiples of the other cycles exist. If there is a 22 year cycle, there is also a 44 year cycle, etc, but we refer to all of these as the 22 year cycle. Similarly the peak in forcing from the prime multiples of the shorter cycles also exists (17x86.5 and 7x210). | |||
| :The proper place for this, is both here, because the periodicity is not thought to be due to solar variation (the shorter cycles) and in the Global warming article, because this paper reinforces the importance of these shorter cycles in driving climate variation. Note, that superpositions of peaks and minima of these cycles have also been implicated in the maxima and minima in the climate record of the last millenium, even if the 1470 signal has not been specifically identified. There are other levels of reinforcing superposition than just this particularly notable 1470 year peak.--] 09:37, 21 March 2006 (UTC) | |||
| Ah. Well, that makes one particular decision rather easy ] 10:08, 21 March 2006 (UTC) | |||
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Chart looks rather out of date
The chart needs updating - as it ends in 2006 - missing the latest solar cycle. 131.111.23.90 (talk) 14:46, 7 April 2014 (UTC)
Historical perspective
Is this quote really helpful? First off, it talks about weather prediction, not climate. The quote itself is ambiguous, open to interpretation as either: "history has shown time and again that it is pseudo-science" or as "in those days it was seen as pseudo-science, but now we have a better understanding". The intro of the source text would be a better choice imo:
- Since it is the Sun's energy that drives the weather system, scientists naturally wondered whether they might connect climate changes with solar variations. Yet the Sun seemed to be stable over the timescale of human civilization. Attempts to discover cyclic variations in weather and connect them with the 11-year sunspot cycle, or other possible solar cycles ranging up to a few centuries long, gave results that were ambiguous at best. These attempts got a well-deserved bad reputation. Jack Eddy overcame this with a 1976 study that demonstrated that irregular variations in solar surface activity, a few centuries long, were connected with major climate shifts. The mechanism was uncertain, but plausible candidates emerged. Ssscienccce (talk) 20:18, 20 October 2013 (UTC)
- The article itself is rife with such conflicts. I don't expect an easy resolution. Batvette (talk) 12:50, 7 November 2013 (UTC)
Solar constant
The article states that "The amount of solar radiation received at the outer limits of Earth's atmosphere averages 1366 W/m." Yet the Misplaced Pages article on the solar constant gives the value of 1361 W/m. Can anyone explain the discrepancy? Thanks. Mhklein (talk) 20:11, 27 March 2014 (UTC)
- The lower estimate is more recent. Don't know if it is controversial. See Solar irradiation. Lfstevens (talk) 06:06, 16 July 2015 (UTC)
- I moved the order of these around slightly, to put the solar constant before the variation in solar constant, but didn't change the actual number without a canonical reference. Different sources do use slightly different totals. Several links were redirects to "solar irradiance", so I consolidated these to just one place. Geoffrey.landis (talk) 17:34, 19 July 2015 (UTC)
Predictions based on patterns
This section is a bit rubbish. Firstly, it "predicts" the 2010 peak, and no-one (including me!) has bothered update it for whatever happened. Secondly, its almost all about "predicting" climate (has it been copied in from elsewhere) not predicting the cycles, so it belongs under the climate heading William M. Connolley (talk) 08:15, 16 February 2015 (UTC)
Cosmic ray claim
Why is the stuff on cosmic rays in there? It doesn't apply to solar variation in any way. Lfstevens (talk) 16:41, 15 July 2015 (UTC)
- I'm not sure I understand the question. The sun's magnetic field deflects galactic cosmic rays. Thus, cosmic rays decrease with higher solar actitity. So this is related to solar variation.
- However, if you're just saying that there's too much on this subject for the article -- well, ok, maybe there is, and possibly it should be compressed and put into a single subsection, instead of spread over several.
- --by the way, you changed the term "galactic cosmic rays" to just "cosmic rays" in several places. I'm going to change those back-- the more generic term "cosmic rays" can also refer to solar proton events, which of course increase with solar activity. Geoffrey.landis (talk) 20:37, 16 July 2015 (UTC)