Talk:Paleoclimatology/Archive 1

Untitled
Paleoclimatology Evaluation: This article is very informative and concise, however its introductory paragraph and history sections are lacking in content. Almost no historical information has been provided. Quite a bit more detail should be added to complete the sections.There are also a few value statements within the body of the text that should be removed to eliminate bias or a persuasive nature. The lead to the main body text is vague and uninformative. The section titled "Internal Processes and Forcings" could be rewritten in a clearer manner and some grammatical errors are present throughout the body of the article that need corrected. All links throughout the text are functioning, however there are several sections that lack citations. There is also some out of date information in this article such as references from 2004. How and by whom was the study of paleoclimatology was discovered? What limitations are associated with ice core records? This claim should have further support. KeyanaA (talk) 04:58, 3 March 2017 (UTC)KeyanaA

Graph temperatur of planet Earth
I think the IPCC projections about 2050 and 2010 should be removed from the graph, since it's supposed to be about the temperature records and not about speculation on future developments. There are several other articles for that. — Preceding unsigned comment added by 141.30.248.186 (talk) 14:35, 11 June 2019 (UTC)

Life flourishes in Cambrian
The section "Life flourishes in the Cambrian" doesn't belong here. My impression is that it contains nothing that isn't already well-told now at other entries, i.e. Cambrian. I think the opening should explain instead how there is climate before there is life, but that life and climate have evolved in synchronicity since the first biotic free atmospheric oxygen. Then follow with the tools of paleoclimatology, for which there's already a stub. --Wetman (total amateur)


 * (User:Terrell Larson 2005/04/28)This artical needs to be greatly expanded. I do not like the recent 2 million years in here.  The reason is that this is more in the realm of contemporary climate change and that is being argued to death in the global warming and climate change areas.  This artical should consern itself with the paleoclimate (which of course does include everything except perhaps the recent past.)


 * The thing I am worring about is that if we allow much mention of the recent past then we run the risk of all the global warming folks hopping in here and destroying this artical. They have a very short focus.  In fact, if we contrast the encyclodeadia Britannics to the time since say the early Cambrian then we find each of the 19 books will represent about 30 million years.  On this scale a page represents about 30,000 years and a single line about 200 years.  Thus our global warming folks are looking at about the last 5-10 lines of the last page of the last book.  Everything that has gone on before is irrelevant to them.


 * Tim Patteron from Carlton university has now published a report that the geological climate record does not show a correlation between CO2 levels and temperature changes. Specifically the ordovician atmosphere was 13x higher in CO2 than today and they went into an ice age.  This shows any coupling between CO2 levels and global warming is weak.  However when you try to tell this to the people who are writing the climate change artical - it falls on deaf ears.  So I hope they stay away from here with their religeous wars.


 * The point I am trying to make is that the paleoclimate can tell us a lot about how the present cliamte operates. OTOH the present climate will not tell us anything about the paleoclimate.  This point is totally lost on most of our climatology and global warming folks.  They think 50,000 years is a long time and that 2 million years is an incredibly long time.  Most of their data is less than 20,000 years old.  In fact, many are trying to forecast from data which is less than 100 years old.  It is mind boggling to think that people will beleive that you can make meaningful predictions of the climate of a planet more than 4.5 billion years old from data collected over a few hundred years.  They simply have no concept of the geological time scale.  Since they ignore the evidence in the rocks and fossils their ideas are meaningless and not much different than the creationists who think God created the earth about 5,000 years ago.  Well - maybe he did - and if so then he created 4.5 billion years of the earth's history at the same time!


 * I disagree with you here. The conditions in many respects are completely different in ordovician, and the uncertainty is much higher for paleoclimate reconstructions that far before present. And we try to predict the mere 100 years of future, not million years. For these reasons, focussing at climate history at scales of 100s of years, maybe few orders of magnitude more, makes perfect sense to me. Not to mention, of course, that basic physical principles (as well as astrophysical evidence) reveal the certain CO2 impact on temperatures. --134.76.233.140 (talk) 16:29, 2 March 2011 (UTC)

Cryptozooic
What is this Cryptozooic business? What time system is this from? It's not GTS 89.


 * (SEWilco 07:59, 12 Aug 2003 (UTC)) Cryptozoic is an obsolete term. Click on Cryptozoic and you'll find mention at the bottom of that page. (It was already on this page when I saw it...)  This page needs a lot of cleaning.  There is duplication with Earth's atmosphere which can be removed here, and instead put climate info.  I think it would be better to build up all that timeline from research links, not start with a list.


 * (User:Terrell Larson 2005/04/28)I know cryptozoic is obsolete. It can be changed.  It was my opinion when I wrote the original artical that it needed an interoduction and since the study of climate is closely allied to the life forms it supports, I chose to start from there.

Cyanobacteria and Archaea
If the Banded_iron_formation are the product of photosythetic oxygenic cyanobacteria and Archaea may be as old as 3.8Ga, the timeline at the end of the Paleoclimatology page should be updated to reflect this. Currently, only bacteria are listed at 3.45 Ga.

Phanerozoic Climate and cosmic ray flux?
How controversial is the following statement, which currently is in the article?:

"Qualitatively, the Earth's climate was varied between conditions that support large-scale continental glaciation and those which are extensively tropical and lack permanent ice caps even at the poles. The time scale for this variation is roughly 140 million years and may be related to Earth's motion into and out of galactic spiral arms (Veizer and Shaviv 2003)..."

Clicking on the first chart links to cites to the following:


 * Shaviv, N. and Veizer, J. (2003) Celestial driver of Phanerozoic climate? GSA Today July 2003, volume 13, number 7, pages 4-10. 


 * Royer, Dana L. and Robert A. Berner, Isabel P. Montañez, Neil J. Tabor, David J. Beerling (2004) CO2 as a primary driver of Phanerozoic climate GSA Today July 2004, volume 14, number 3, pages 4-10. 

-- and the second article appears to contradict/refute, or at least substantially qualify, the first...

So, if the above quote from the article is controversial shouldn't this be indicated? Moreso than just the current "may be" qualifier... lots of folks feeling very passionate about "global warming" and "greenhouse gases", nowadays, maximum precision would seem to be a good idea...

I'll put both article cites & links into the bibliography, here.

--Kessler 20:53, 24 July 2006 (UTC)


 * V+S's stuff is definitely controversial; see various RealClimate postings William M. Connolley 20:38, 8 April 2007 (UTC)


 * I agree with William Connolley that Shaviv's work is highly controversial. This is not necessarily a problem in itself. However, since Wikipedia should not promote a certain point-of-view, this whole paragraph is biased in the way that it only presents a minority of the knowledge of the astrophysics/climatology community. Another point is that, reading Shaviv's work, it is still quite immature in the sense that it is a small group of scientists trying to establish a whole set of causalities - work which would take the larger 'concensus' community shorter time. For example, in comparing several of Shaviv's papers it becomes clear that the spiral arm passage frequency estimates noted therein seem inconsistent. In conclusion, I think this paragraph needs more references and/or removal of the statements related to Shaviv & Veizer. I am a scientist in complex systems and have no interest in taking side in the discussion, but it is clear that Shaviv & Veizer is receiving too much attention to results which are, most likely, inaccurate. (Plogp (talk) 13:42, 24 October 2008 (UTC))


 * I asssume that you both basically refer to realclimate org. I suggest to take into account shavivs either scientific and (with regard to a beer to peer connection of Rahmstorf and Jahnke in Potsdam) sort of personal rebuttal on.
 * One has to see that Shavivs papers - if one accepts the hypothesis - would explain the young faint sun paradoxon and the course of paleoclimate from start till the last ice ages, as displayed in the Schönfeld pic I copied downstairs. Thats a bold one, at least one William (von Ockham) would like it and it has sparked either controversy and more research in different fields, to name only Scherer et al. comprehensive (as well from a geochemist perspective) study 2007 in Space Science Reviews 2007.
 * The 2007 IPCC reports strongly attribute a major role of anthropogenic carbon dioxide in the ongoing global warming, but as "different climate changes in the past had different causes" a driving role of Carbon dioxide in the geological past is not purported. Sun has lead the dance with a quite active earth in the past.
 * Empiric evidence of a stronger solar influence is acknowledged by 2007 IPCC papers. Besides Co2 Climate sensitivity margin is still wide, the lab value around 1.2, the attributed (based on leveraging water vapour) between 1.5 and 6.2, best guesses around 3. IMHO there is leeway for solar influence - which might interact with CRF - or CRF itself
 * Compared to 2001 the early palaeozoic ice age (pre 400 with high CO2) is left out in the 2007 IPCC scientific base (similar to the whole dispute Royer Veizer, not to metion Rahmstorf editorial), the weaker Ice age around 150 as well. Hmmm. The fit in the last 60 M years doesnt hold too much water. To say it short, the IPCC is and has to be rather cautious about giving CO2 a drivers role in the geological past, starting with Ice ages already, not to speak of the previous eons. The sharp controversy William mentiones was especially about the puported role in industrial times versus the carbon dioxide
 * A William Connolly quote on his disk "Geologists are trained to look at long time scales. But those time scales are irrelevant to current change. It also makes the geologists tend to feel left out, overlooked and hence bitter." may refer to some aspects to the dispute ;) as well. --Polentario (talk) 03:18, 25 January 2009 (UTC)


 * Real life sources about the palaoclimate have been added, I used structure and evidence of the german article 'history of the atmosphere' to get more form in it
 * Most of the points about concentrations have been taken out tof the Scosese Web log, I would be careful with using them, as well with regard to GA
 * I do not assume that the greenhouse controversy is the focus of this lemma, so used a wording giving both parties the time span were they fit best and put the best and primary available references in footnotes BR --Polentario (talk) 23:09, 25 January 2009 (UTC)

Wiki Education Foundation-supported course assignment
This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Jriley97, Blenz1126, Vogelj265, 4timothyduncan, Ekorte331.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 06:02, 17 January 2022 (UTC)

Rm layer stuff
I took out:


 * The ice in glaciers has hardened into an identifiable pattern, with each year leaving a distinct layer in an ice core. It is estimated that the polar ice caps have 100,000 of these layers or more.

This is definitely wrong. Whether or not your get an identifiable yearly layer depends on the accumumation rate and conditions. What is layer-counted is more often isotope/chemical records not anything visible. Layer counting only goes back ?50kyr?, and that only at some sites (greenland). The 100k layers sat oddly with the next sentence which says (correctly) that cores go back 800kyr.

This needs xref to ice core and proxy (climate) and other stuff William M. Connolley 20:41, 8 April 2007 (UTC)

Will GA ever be an option?
Once inline references are placed within the article and an adequate lead is placed at the top, the article will be ready for GA. It seems to fit the other criteria. Thegreatdr 18:46, 1 June 2007 (UTC)

Removal of CRF description
The section on CRF as a possible driver has been unilaterally removed with the edit summary this section is unacceptable as-is: you cannot present one hypothesis as the leading theory. I fail to see that it is doing that, it is listed as one driver amongst many in the "controlling factors" section, but admittedly the only one in that time frame. It is clearly presented in NPOV terms as just a hypothesis and is properly referenced. Indeed, it was the only driver in the whole section that was referenced at all, and at the time I put it in, that was 80% of all the references in the entire article. If there are competing theories, the article should be balanced with the alternatives, blanking the whole is not constructive. I feel a little offended that my efforts here have been treated as if it was some passing vandalism of no consequence instead of engaging in debate.  Sp in ni ng  Spark  23:36, 25 January 2009 (UTC)


 * Basically its a great hypothesis, since it explains a lot of unsolved issues, one dieagrma in Shavivs 'Paradox' paper shows the whole course of climate during the last 4,5 Billion years
 * Veizers first papers 1976 were used for the first suggested solution of the faint sun paradox btw and he has provided further geochimical evidence
 * However you have to understand that it has sparked -as a siide effect - controversy, especially in the global warming debate and you shouldn jump in the middle of astronomical mechanics when the CRF mechanism hasnt been explained / is still object to denial. BR --Polentario (talk) 01:16, 26 January 2009 (UTC)
 * So if I understand this correctly, the objection is that there has been no causal link established between CRF and climate whereas the other drivers have an understood mechanism. The solution then, is to say in the article that it is based on statistical correlation only (although one possible mechanism from the paper is already mentioned).  The paper of Royer et al could also be referenced as this disputes the degree of correlation.  Of course, saying all this will make the section longer and give it more prominence.
 * I am a bit confused how this is getting caught up in the global warming debate. The CRF cycle period is of the order of hundreds of millions of years but the anthropogenic global warming timescale is a couple of centuries.  Anyone who believes that one can explain the other is either an idiot or a politician.  in any case the deleted text did not try and make this connection in any way so that should not be an argument against its inclusion.  Sp in ni  ng  Spark  07:21, 26 January 2009 (UTC)


 * I have copied the post below from my talk page so it is opened up for debate. I hope Polentario does not mind. Sp in ni  ng  Spark  20:49, 28 January 2009 (UTC)
 * What is your opinion about the paläoclimatolgy article now? You have an interesting way to argue for your point and work and avoid conflict, I appreciate that very much. If were talking about pictures, I would love to have the 2003 Shaviv diagram (in ) combined with a scheme using the overall climate evolution in File:Erdgeschichte.jpg. It would be a very strong illustration  of the overall view, not only the phanerozoic you already have done. What you think? BR --Polentario (talk) 00:03, 27 January 2009 (UTC)


 * I have done some copyediting on it to improve the English. Please check that I have not caused any factual errors.  The main thing I would comment on is that the faint young sun pararox/solar minimum issue should be in the next section (very long term) since the section it is in now is only supposed to be up to the one billion years scale.  I can certainly produce a diagram in SVG along the lines you suggest, but I would worry that overlaying the Shaviv data on something else could amount to WP:OR synthesis.  I would prefer to take all the data points just from Shaviv so that the data can be attributed.  Sp in ni  ng  Spark  20:49, 28 January 2009 (UTC)

Feel free to move the section, I wouldnt mind
 * I think one should mark the grey band / Display of ice ages in Shavivs figure more outspoken and strongly indicate that the it was warm and cozy from very early.
 * Its not OR since thats already part of the diagram, however not as evident as in the Schönwiese pic. A major Cold one at 2,4 Giga BP and the Ice age / Warm age cycles start as late as 950 Million BP is established text book stuff.
 * Shavivs basic calculations cover the basic trend, the meteorite evidence is in line with some of the ice age / hot age cycles within the reach of certainity. --Polentario (talk) 09:57, 29 January 2009 (UTC)
 * The problem as I see it is that to divide the Shaviv diagram arbitrarily into warm and cold epochs would be to insuate something into the diagram that Shaviv has not specifically said. Besides which, the shape of the curve in Shaviv, although generally the same form as the Erdgeschichte diagram, deviates quite markedly.  Any attempt to simplistically place a horizontal line on the Shaviv diagram does not result in the same periods of icy versus warm climate as shown on Erdgeschichte.  I could create a similar English diagram in SVG rather than use the Shaviv data, but what is its source? Is this book the source?  Would that give you what you want?  Sp in ni  ng  Spark  21:24, 29 January 2009 (UTC)


 * Sorrym, didnt see your entry. Yes Schönwiese is the source, but Shaviv has some climate indications in his diagram as well. I'd prefer to show it more explicite. BR --Polentario (talk) 14:58, 31 March 2009 (UTC)

This conversation seems to have lapsed. Maybe I got busy. Time to re-start it I suppose. I said this section is unacceptable as-is: you cannot present one hypothesis as the leading theory. SS said: "I fail to see that it is doing that" but I fear it is all too obvious why it is doing that: it is presented, as I said, as the leading, nay *only* explanation, and this is unacceptable William M. Connolley (talk) 20:51, 23 April 2009 (UTC)
 * You really havn't been paying attention at all have you? The wording was substantially altered and added to to try and address your concerns. You have returned after 3 months and just deleted the lot again without joining in the discussion at all.  THAT is unacceptable.  As I said above, if there are other theories, lets add them, if what I have written is biased, lets edit the bias out.  Wholesale deletion without discussion just is not on.  I am going to restore this, you deleted it AFTER you stated in an edit summary that you were going to post on the talk page.  Sp in ni  ng  Spark  21:09, 23 April 2009 (UTC)
 * You're right, I'm a complete bozo and just don't know what I'm doing. All well, I'll do my best to keep up with your superior intellect. So: I removed the text as I read it today: as I said, it was unacceptably biased. No, you can't keep the horribly biased text whilst waiting for it to be unbiased William M. Connolley (talk) 22:17, 23 April 2009 (UTC)
 * Are you not prepared to help work on this at all? What I am asking is will you collaborate rather than just deleting?  You may not believe me, but I really do not have any bias here or POV I wish to insert.  Sp in ni  ng  Spark  22:39, 23 April 2009 (UTC)
 * Yes, I'm quite happy to collaborate William M. Connolley (talk) 08:33, 24 April 2009 (UTC)
 * So could you start by explaining what you think would make this text acceptable? From my point of view I am not pushing galactic cycles as the only explanation of temperature change.  I have inserted it as one of many possible drivers.  While it is true that this is the only one in the 10^8 time range, that is just coincidental, I organised the "drivers" section by increasing time scale to try and put some structure on it, not to push some POV.  I am not deliberately excluding any other notable proposals, it is simply that I do not know of any.  Do you?  As for the diagram you claim is inaccurate, well it accurately reflects Shaviv and Veizer's paper, which is all that it is claiming to be.  You say you are willing to collaborate, but so far all I have from you is total deletion, no additions, no improvements, no attempt to edit out the POV you think is there.  Attempts were made after your first deletion to address your concerns as you can see from the discussion above, but it is quite difficult to guess your thinking if you do not take part in the discussion.  It is particularly galling that this piece was well referenced, which is more than you can say for most of the rest of the article. (edit) Oh, and I am not proposing keeping horribly biased text whilst waiting for it to be unbiased, I am proposing fixing it right now.  Sp in ni  ng  Spark  09:25, 24 April 2009 (UTC)
 * The diag (and the text) accurately reflects S+V's paper. But that isn't good enough. It also has to accurately reflect the balance of opinion, which is rather different. If we can agree that is true, I can try to find some more balance. Or you can William M. Connolley (talk) 10:10, 24 April 2009 (UTC)
 * I agree that the article as a whole should reflect mainstream academic opinion. As long as it is made clear that the diagram represents what S&V are saying, and no more, there is no reason not to include it.  I am aware of the criticism in the paper of Royer mentioned above.  My reading of that paper is that Royer shows a great deal of dislike for the S&V theory but stops short of outright rejection.  He end up saying that there is some correlation with CRF, but rather less than S&V claim.  He makes no criticism of S&Vs claimed CRF variation, and in fact uses the S&V CRF data in his own revised graph.  Perhaps Royers version of the graph could be shown for balance?  Sp in ni  ng  Spark  10:46, 24 April 2009 (UTC)

Peer Review
Is it time to drop the requirement that papers that are cited by this article be peer reviewed. After all it the AGW crowd is willing to, “redefine what the peer-review literature is” to keep out the work of skeptics, no matter how well researched, then the requirement for peer review is just a POV requirement. 173.52.9.63 (talk) 17:23, 24 November 2009 (UTC) So the climate science deniers from conspiracy blogs can add their evidence-free conspiracy theories and faked graphs? — Preceding unsigned comment added by 124.170.203.120 (talk) 12:32, 12 May 2015 (UTC)

NOAA link
I disagree with this reversion. I thought the IP was right to change the link to the NOAA paleoclimatology portal page. This has links to pages with a wealth of information on various sub-topics such as paleo fires, corals, loess and much more not covered in our article, or only briefly. It makes sense to link to the home page of a site, besides which, the current page linked has a very annoying gallery slide show. There is an alternative "What is paleoclimatology" page on the site which is much more informative, but I would still be in favour of the portal page as both these sub-pages are easily reached from the home page.  Sp in ni ng  Spark  20:47, 2 December 2009 (UTC)
 * On second look, you have a good point; I will self-revert, Awickert (talk) 22:03, 2 December 2009 (UTC)
 * Why not link to them both? -Atmoz (talk) 22:24, 2 December 2009 (UTC)
 * Well, because there is no need, the NOAA site has good navigation links, and there is a general principle to keep external links to a minimum.  Sp in ni ng  Spark  01:37, 3 December 2009 (UTC)

Roman Warm Period
Why does this article not mention the Roman Warm Period? There are plenty of references to a Roman Warm Period in the peer reviewed literature, e.g. McDermott et al. 2001, Science. Alex Harvey (talk) 01:25, 15 March 2010 (UTC)

Your link doesn't work and you clearly haven't read the McDermott paper. Did you pick up the title from a conspiracy blogger who hadn't read it either but misrepresented it?

Here's the paper : http://www.sciencemag.org/content/294/5545/1328 — Preceding unsigned comment added by 124.170.203.120 (talk) 12:54, 12 May 2015 (UTC)

Because it was a minor blip in a regional area. It was not global. The main places you'll find referencing it is anti-science climate conspiracy blogs and the more trashy tabloid press. — Preceding unsigned comment added by 124.170.203.120 (talk) 12:50, 12 May 2015 (UTC)

New correlation discovered by geologist Lorraine Lisiecki
'''In an analysis of the past 1.2 million years, UC Santa Barbara geologist Lorraine Lisiecki discovered a pattern that connects the regular changes of the Earth's orbital cycle to changes in the Earth's climate. The finding is reported in this week's issue of the scientific journal Nature Geoscience.''' —Preceding unsigned comment added by Brian Pearson (talk • contribs)


 * Why are you bolding this? The "discovery" you mention is basically Milankovitch cycles, nothing really new there. What appears to be new is a sensitivity estimation. This would be interesting - but afaikt not very accurate, as many other factors influence climate on that long a scale (geological changes). --Kim D. Petersen (talk) 01:05, 9 April 2010 (UTC)


 * You are right, but it does add concrete evidence.Brian Pearson (talk) 21:25, 9 April 2010 (UTC)

Earth orbit
Earth orbit is decaying 20m/yr (measured relativistic decay). If there were no gas giants in the vicinity of the Sun when Earth was condensed, then the Earth orbit was at its' beginning there where Mars is now. That is roughly 200 million km from the Sun. —Preceding unsigned comment added by 193.77.42.100 (talk) 07:53, 16 August 2010 (UTC)

There are two options:

1. Our stellar models are wrong and the Sun actually fades with time.

2. Our solar system had (as we see with other newly discovered star systems) one or more heavy planets close to the Sun, that have since in-spiraled into the Sun. These giant planets could perhaps allow for Earth orbit to be closer to the Sun as it is now, billions of years ago.

"Planet's timeline" section comment
I'm not sure the bulky geologic timescale illo really adds much to this section -- I hadn't looked at this article in awhile, and it confused me for a moment. Do we really need it here? TIA, Pete Tillman (talk) 20:09, 12 June 2011 (UTC), Consulting Geologist, Arizona and New Mexico (USA)
 * Removed and retitled section. Does that work? Vsmith (talk) 21:11, 12 June 2011 (UTC)


 * Yup, much cleaner. Thanks! Cheers, Pete Tillman (talk) 22:46, 12 June 2011 (UTC)

Effect of minor planets on Earth's orbit
"Astronomy & Astrophysics is publishing a new study... [which] found that close encounters among these bodies lead to strong chaotic behavior of their orbits, as well as of the Earth's eccentricity. This means, in particular, that the Earth's past orbit cannot be reconstructed beyond 60 million years.... This means that the Earth's eccentricity, which affects the large climatic variations on its surface, cannot be traced back more than 60 million years ago. This is indeed bad news for Paleoclimate studies." at PhysOrg.com. Also see Climate change studies vexed by Vesta.

If I'm reading this correctly, this discovery would only seriously affect paleoclimate studies of times before 60 mybp. And it's always best to wait awhile before including new results in the article. Best, Pete Tillman (talk) 19:06, 18 July 2011 (UTC)

Graph is misleading
Regarding the paleoclimatological history graph, the X axis is labeled but nevertheless the changes in scale are misleading. Cursory viewing of the graph, or even examination, doesn't immediately reveal that the far-left edge covers 10^6 more time per linear unit than the right edge. I'm not a regular wiki editor, nor a professional media editor but have rescaled this image with photoshop to represent a consistent time-span across the x-axis. Not sure how to upload to wikimedia, so here's the link. http://img853.imageshack.us/img853/6025/allpalaeotempsscaled.png

Styopa (talk) 18:32, 12 February 2012 (UTC)


 * The "changing x scale" seems obvious on close examination. Two reasons: first more data points in more recent time and more interest to to current human environment. Your "constant scale" diagram will either be too large or too cluttered in recent millenia for readability. Perhaps an explanatory note to address your concerns for the users who don't see the changing scale as obvious. Vsmith (talk) 22:49, 12 February 2012 (UTC)


 * I agree with that. A uniform scale would not be an improvement.  Spinning  Spark  22:32, 13 February 2012 (UTC)

I have two issues with this chart/graph. 1. the x-axis jumps between logarithmic and linear timescales 2. the y-axis is *delta* T meaning the represented data is not "Global Temperatures" as the title suggests, but infact the represented data is "Global Temperature Changes" Note: that is "changes" as a noun, not "changes" the verb Please correct me if I am wrong, but I think this image requires attention. Because as it is, the graph just tells me that: in general, things change more over more time.Ccubedd (talk) 19:43, 26 September 2012 (UTC)

Styopa, that is very interesting to look at your adjusted graph. Thanks to your proper organization of the data, the most profound conclusion I draw is that for the past 500 million years, the Earth has spent MUCH more time heating up, than it has spent cooling down. I would very much like as much feedback on this conclusion as possible. Thank you. Ccubedd (talk) 19:48, 26 September 2012 (UTC)

The rejigged graph based on the Petit et al 1999 Vostok paper is also misleading in it's caption about the left side being "today's date." I know someone reversed the timeline and that is probably what it refers to, but leaving it saying 'today's date' suggests to the casual reader that it is the current 21st century date. As the CO2 data ends in pre-industrial times at 280 ppm, then the CO2 data clearly ends in the 1800's, not the 21st century. If CO2 levels in the last 200 years were added, the plot would go off the graph. — Preceding unsigned comment added by 124.170.203.120 (talk) 12:39, 12 May 2015 (UTC)

Earliest atmosphere
[quote]The outgassings of the Earth was stripped away by solar winds early in the history of the planet until a steady state was established, the first atmosphere. Based on today's volcanic evidence, this atmosphere would have contained 60% hydrogen, 20% oxygen (mostly in the form of water vapor), 10% carbon dioxide, 5 to 7% hydrogen sulfide, and smaller amounts of nitrogen, carbon monoxide, free hydrogen, methane and inert gases.[citation needed] [/quote]

Any analytical chemist will confirm that this particular citation of chemical analysis is nonsensical. All of the evidence points to a very low free oxygen content (as the simple substance dioxygen gas) -- a few parts per thousand at most. If oxygen means an elemental composition (the only way that "as water vapour" makes any sense), then what about the element oxygen in carbon dioxide? Is that double-coounted? Not counted at all? Why is carbon dioxide treated differently to water?

Or does the 10% carbon dioxide refer to 10% element carbon in carbon dioxide? (which would mean 26% element oxygen!)

A more consistent and reliable elemental composition for the early atmosphere is needed, with a solid citation. The ones I have access to are rather dated (e.g. Wayne, Chemistry of Atmospheres, Oxford UP, 1991. Chapter 9.4). This source sets the pre-biological level of atmospheric oxygen gas well below parts per thousand. 203.134.51.162 (talk) 01:24, 5 March 2012 (UTC)jrc


 * The sentence is confusing and in need of clarification. I'd say go ahead and use your 1991 ref and do a rewrite. Vsmith (talk) 13:25, 5 March 2012 (UTC)
 * Agreed, either give the elemental, or the (more useful) molecular composition, not a confused mixture of the two.  Spinning Spark  14:04, 5 March 2012 (UTC)

Proposal to merge from Earth's early atmospheres
Information from this article should be merged properly with Paleoclimatology. -Patilsaurabhr (talk) 06:48, 6 December 2012 (UTC)
 * Merge (with redirect) - I think the OP has a point. Mr T  (Talk?)  [ (New thread?) ] 08:53, 6 December 2012 (UTC)
 * Dubious - that page reeks of copyvio, I'm doubtful there is much there that we'd want. EEA is a logically distinct topic, but the current page contents aren't suitable William M. Connolley (talk) 10:13, 6 December 2012 (UTC)
 * Seems that page has been speedied - poof it's gone. Vsmith (talk) 11:41, 6 December 2012 (UTC)
 * Copyvios are rarely as thoroughly referenced as that page was. I would be happy to userfy it for anyone who thinks there may be something retrievable there. It was only speedied on the basis of A10, that is, a duplicate of this page!  Spinning  Spark  18:11, 6 December 2012 (UTC)
 * Seems the material is in the history here as it seems the user attempted to add it, but the result was a bit of a mess. I initially thought it was vandalism and removed it, but now see what was happening. Sorry 'bout that. Anyone care to take a close look and work with the material? Vsmith (talk) 20:47, 6 December 2012 (UTC)

History of the atmosphere
Earth’s Early Atmospheres and the Development of an Oxygen-Rich Atmosphere

I.	Introduction

While the timing of planetary formation of the Earth is generally well-understood, much debate still surrounds the formation and basic composition of Earth’s early atmospheres. When Earth first formed, most of the gases that would make up the earliest atmosphere were either trapped in Earth’s gravitational field from the planetary nebula or were released from Earth’s rapidly cooling crust. Over the next few billion years, Earth’s atmosphere would undergo drastic changes in its composition that would allow the planet to remain above the freezing temperature of water, permit life of all types to develop, and finally become oxidized to the point we know it today.

II. Earth’s First Atmosphere

Shortly after the formation of Earth, the planet’s atmosphere was very thin or more likely non-existent. Debate continues as to how much of Earth’s early atmosphere was made up of hydrogen and helium. One theory is that residual amounts of hydrogen and helium were trapped within the Earth’s mantle in small quantities and were then outgassed due to tectonic activity. The opposing theory maintains that gases from the planetary nebula were captured in Earth’s gravitational field, and thus hydrogen and helium comprised nearly 30% of the first atmosphere. Proponents of both theories, however, agree that most of the hydrogen and helium gases in the first atmosphere were too energetic to be held by Earth’s gravity for long. Hydrogen and helium have two methods by which they can escape Earth’s gravity: thermal escape and loss by electric fields. Thermal escape, in which hydrogen and helium are heated to levels energetic enough to escape Earth’s gravity, causes most of the loss. However, electrical fields created in the ionosphere can also cause hydrogen and helium to be removed from the atmosphere, although in less abundant quantities. The rate at which hydrogen and helium escaped Earth’s atmosphere is a contentious issue, but most research agrees that helium and hydrogen gases in Earth’s first atmosphere were eventually lost so that only a small fraction remained in Earth’s later atmospheres.

III. Earth’s Second Atmosphere

Earth’s second atmosphere came to gradually replace Earth’s first atmosphere as volcanic activity and outgassing caused a change in gas concentrations. The second atmosphere was mostly made up of compounds that more closely resemble our present atmosphere rather than the light element rich first atmosphere. Earth’s crust, which was filled with methane, ammonia, carbon dioxide, nitrogen, and water, was still solidifying and moving across the planet. As plate tectonics continued, volcanoes on the planet’s surface released large quantities of these gases, which were then trapped in Earth’s gravitational field and built up in the atmosphere. The exact concentration of each gas is still highly controversial, especially concerning the amount of methane and carbon dioxide in the atmosphere.

IV. Faint Young Sun Paradox

Perhaps the biggest unknown in Earth’s first and second atmospheres, concerns the faint young Sun paradox. The formation of Earth occurred approximately 4.5 billion years ago when the Sun was smaller and 30% less luminous. With such a reduction in solar radiation, Earth should have had a temperature of 245K, far below the freezing point of water, but it is known that liquid oceans were present back at least 3.5 billion years The current theory is that high concentrations of greenhouse gases such as methane and carbon dioxide kept Earth from freezing. A clear divide exists in the research as to whether carbon dioxide or methane was the greenhouse gas most responsible for warming the Earth. While this article does not seek to evaluate the arguments of either greenhouse gas, the competing theories are important when discussing the evolution of life and its impact on Earth’s early atmospheres.

V.	Methane Solution to Faint Young Sun Paradox

Proponents of the methane theory suggest that because of methane’s long residence time in anoxic environments and its strong greenhouse effect, methane could be responsible for warming the planet. Methane has its absorption spectra in water vapor’s atmospheric window (Fig.1), thus an atmosphere high in methane and water vapor could produce a strong greenhouse effect. However, although methane is released from hydrothermal vents in the sea floor, it is highly soluble in water. Thus, the only way that methane could have been built up in the atmosphere is by the development of methanogenic bacteria. Rock records indicate that methane was present in large quantities during Earth’s early atmosphere. Opponents of the methane theory point to methane’s high water solubility as the main reason why methane could never have built up a high enough concentration to solely keep Earth above freezing.



VI. Carbon Dioxide Solution to Faint Young Sun Paradox

The carbon dioxide greenhouse theory answers many of the unknowns in the methane theory, but it is also fraught with issues. Like methane, carbon dioxide has its absorption spectra in water vapor’s atmospheric window (Fig.1). One of Earth’s earliest life forms, cyanobacteria, released carbon dioxide in large quantities. As carbon dioxide built up in the oceans and then the atmosphere due to cyanobacteria, it would have warmed the planet above freezing. Opponents of the theory counter that weathering on Earth’s surface would have consumed much of the carbon dioxide and, indeed, rock records indicate that, while weathering was occurring, there was 20 times too little carbon dioxide to keep Earth above freezing.

VII. Development of Life

The answer to the competing theories may lie in compromise. Because the atmosphere at this time was rich in nitrogen, hydrogen, methane, and water, sparks like lightning were capable of producing amino acids and sugars necessary to the evolution of life. Eventually, single-celled organisms like methanogens and cyanobacteria formed in the oceans and maintained or increased the levels of carbon dioxide and methane. As both methane and carbon dioxide increased in concentration in the atmosphere, the Earth would have warmed substantially past the freezing point of water . In fact, the hot temperatures created by these two gases’ greenhouse effects would have produced a thick, organic haze similar to the moon Titan. The effect of this thick haze is two-fold. First, the haze would have protected the Earth’s surface and shallow waters from harmful UV radiation, and thus allowed the evolution of life in the upper ocean rather than in the deeper oceans where methanogens and cyanobacteria thrived. Second, the haze would have shielded the Earth from some incoming solar radiation, thus cooling the Earth to temperatures conducive for oxygen photosynthesizers but hostile to methane photosynthesizers.

VIII. Earth’s Third Atmosphere

With the atmosphere now conducive to photosynthetic oxygen production, the amount of atmospheric oxygen began to increase steadily. Though some scientists believe photo-dissociation of oxygen from hydrogen may have been a factor in increasing oxygen levels, biological photosynthetic oxygen production was an exponentially larger factor. Meanwhile methane, which has a very short residence life in aerobic conditions, began to decrease in the atmosphere and oceans as oxygen began to rise, leading methane to evolve into higher hydrocarbons . As methane decreased in the atmosphere and oceans due to solubility, production of methane decreased as well because methanogenic bacteria cannot function in even minimally oxygenated environments; thus a positive feedback of methane depletion caused a rapid decline in atmospheric and oceanic methane.

IX. Timing of Oxidation of Earth’s Atmosphere

The timing of the oxidation of Earth’s oceans and atmosphere has come into much clearer focus during the last decade. The accepted range for the oxidation of Earth’s oceans based on rock records is 2.45 billion years ago to 2.22 billion years ago. This date range is largely based on red iron beds on the sea floor. As oxygen increased in the ocean, it began to oxidize the iron it contained, which consequently turned the iron red. The first red iron bed formations formed around 2.45 billion years ago, indicating the upper bound of the oxidation of the sea. Once most of the iron in the sea was oxidized, oxygen could escape to the atmosphere. Evidence for the timing of atmospheric oxidation is found in sulfate isotopes. Diagenetic pyrite in the Rooihoogte-Timeball Hill rock formation further narrows down the range of atmospheric oxidation to between 2.45 billion years ago and 2.32 billion years ago. The pyrite, which can be dated through the sulfur, formed 2.32 billion years ago and is embedded in a carbon-rich rock bed. Therefore, it can be assumed that the organic layer in which the pyrite is embedded is at least 2.32 billion years old, and thus oxidation of the atmosphere must have occurred prior to 2.32 billion years ago. While the newly oxidized atmosphere was not exactly the same as today’s atmosphere, due to the fact that land plants and animals had yet to evolve, this third atmosphere was far more similar to the present than any of Earth’s older atmospheres.

X.	Review

In the span of just over 2 billion years, Earth had undergone three completely different atmospheric compositions. Earth’s earliest atmosphere was made up of light elements found in the planetary nebula that formed the solar system. After these elements were outgassed, volcanism, as it often has in Earth’s history, changed the atmospheric chemistry of the atmosphere which allowed life to evolve. Life on the planet, however, was not an idle bystander to the changing atmosphere but rather was a catalyst for stark changes in oceanic and atmospheric composition. Single-cell bacteria kept the planet from freezing over due to their methane and carbon dioxide emissions, yet when the planet responded to these emissions by warming beyond the ideal temperature range of the bacteria, life further evolved and caused the oxidation of Earth’s ocean and atmosphere. Though the complex interactions between gases, water, and life make Earth’s early atmospheres difficult to resolve, it is this complexity that allowed formation of life as we know it today.

XI. Ongoing Research

Further research on Earth’s early climate is needed. Recently, scientists at Rensselaer Polytechnic Institute have proposed that perhaps Earth’s early atmosphere was not as oxygen-poor as previously thought. By studying the chemical makeup of magma and its interactions with Earth’s crust and atmosphere, it is apparent that a connection exists between the atmospheric oxidation levels and the presence of certain minerals, particularly the cerium content within zircon. Researchers have found that cerium exists in two different states of oxidation. An increased presence of the more oxidized form is directly correlated to increased atmospheric oxygen levels following igneous rock formation. Other studies should look at whether outside events, such as large meteor impacts, could have played a role in bringing water and gases to Earth. In addition to these studies, much of the current research focuses on dating the transition times of Earth’s early atmospheres.

Changing info box
Shouldn't the info box from Climatology be used instead of the Geology box? Prokaryotes (talk) 16:57, 10 April 2014 (UTC)
 * I would say geology was more relevant here. Compare paleobiology and paleobotany.  But then again, there is paleozoology which does something different.  Spinning  Spark  22:06, 11 April 2014 (UTC)
 * Ok, thanks for the clarification, SpinningSpark. Prokaryotes (talk) 22:15, 11 April 2014 (UTC)

Controlling Factors
The part has a bias on "cosmic rays" according to Jan Veizer, who is part of a dispute about influence of cosmic rays on climate change. He doesn't think that greenhouse gases are the main driver for climate change. The article scope is to define the science field paleoclimatology, not to use a big chunk of the page to outline the opinion from Veizer. Further is the entire section already covered in this page https://en.wikipedia.org/wiki/Climate_Change#Causes On top of this is the entire section written very poorly, quote: "The Earth today is considered to be prone to ice age glaciations." ... Prokaryotes (talk) 17:47, 12 April 2014 (UTC)
 * Remove As outlined above. Prokaryotes (talk) 17:23, 12 April 2014 (UTC)
 * What we could do is write a paragraph or two and set a link to causes. Prokaryotes (talk) 17:46, 12 April 2014 (UTC)
 * I don't think that it is reasonable characterise the whole section as being biased to the views of Veizer. I appreciate that he is not flavour of the month because of his views on anthropogenic global warming but that does not mean that everything he has ever published is worthless.  Do you have anything to support such a position?  Despite your claims, the majority of the text is not cited to Veizer so even if everything that is so cited were removed there would still be a substantial amount remaining.  The "short term" section (wich is the only part of relevance to man-made effects) does not even mention Veizer or his views and states greenhouse gases as a cause as a fact without discussing any alternatives.  Laughably, this part of the text is not cited at all.  The article is not exactly kind to the CRF explanation, so I don't think it can be claimed that it is pro-Veizer.  Reducing the "profile" of Veizer would probably require removing some of the criticism.
 * I am not trying to push an anti-man-made global warming agenda, just the opposite if anything. I read about the theory that climate was influenced by galactic motions all the way back in the 1970s, long before anyone had even heard of global warming, let alone there being a controversy over it.  I came to this article to learn more about that galactic motion theory and found there was nothing.  I no longer had my original sources (although I am pretty sure that they were something we would consider reliable) and asked on the ref desk for information.  I was pointed to a Shaviv and Veizer article by User:Dragons flight who I do not believe is a global warming nay-sayer either.  I had no idea I was naively walking into a GW bear trap.  I don't expect that there are huge numbers of us survivors from the 1970s who are still trying to find info on this question, but for those that there are, Wikipedia should be providing the service.
 * I have no idea why you think that the drivers of archeoclimate are irrelevant to the paleoclimatology article. Discovery of the causes of climate change are surely one of the main goals of paleoclimatology.  Spinning  Spark  19:57, 12 April 2014 (UTC)
 * It's not a bear trap;) You have a point in general, but as you write, it is poorly referenced, besides the parts on cosmic rays. However, cosmic rays belong into cosmic ray. If we begin to feature special theories, others will add more theories. The archeoclimate is outlined (Celestial movement) on the climate change entry, why keep this section here? It is redundant. Further has the article already the sections "Reconstructing ancient climates", "Notable climate events in Earth history", "History of the atmosphere", "Climate during geological ages", i think this covers everything for paleoclimatology. Then there are snippets in this section (other than related to CR's) which are wrong and weasel worded. So, i suggest to boot this section, make a new section on something like "Climate change causes on geological time scales" and mention the internal and external forcings there briefly (emphasis on https://en.wikipedia.org/wiki/Climate_Change#External_forcing_mechanisms ) and link back to the main entries.
 * I think basically the cosmic rays stuff has no credibility, see this search Prokaryotes (talk) 20:36, 12 April 2014 (UTC)
 * I'm not trying to argue that CRF is credible, I simply don't know (although I don't think you can use what is essentially a blog to discredit published papers). Nor is the article trying to say it is credible as far as I can see, it spends a lot of time giving the criticisms.  Whether or not CRF is credible is really rather beside the point.  If this were some crackpot fringe theory largely ignored by the mainstream then you would have a point.  But Veizer is very highly cited, I am seeing an h-index of at least 60 on Scholar.  Nir Shaviv is also highly cited.  This makes their theories notable, even if they turn out to be complete garbage and Wikipedia should service readers trying to find out about them.
 * I don't see that it would be a problem if more theories were added. We don't have to include every theory if they are marginal, but something as widely discussed as CRF surely needs to be included.  I also don't have a problem (in principle) with moving material to another article and summarising it here.  However, I find it highly objectionable to arbitrarily delete material wholesale altogether.  Spinning  Spark  21:33, 12 April 2014 (UTC)
 * Arbitrarily? If you look at the page version before i edited it here, you can count 9 mentions of Veizer. I've removed it (per "WP:BOLD"), because of the bias of the entry on CR's and my assumption that the entry on paleoclimatology shouldn't evolve around CR's to the extent it is covered, and because this entire topic is not within the scope, because it is already covered at climate change causes (This does include this entire section). Further does Google Scholar only lists 31 cites on cosmic rays climate. CR's are a niche study field, it might have a place as a short mention, but in essence it is not relevant for the article here. Prokaryotes (talk) 22:01, 12 April 2014 (UTC)

Official statement by PIK, in regards to the connection of climate science and cosmic rays: "This theory is not supported by any scientists (including those actually named, who explicitly describe it as wrong). If the position in the galaxy were to have any influence at all on the climate (and the evidence for this is weak), the process would unfold in the course of several million years and, over a period of 20 years, account for at most one millionth of a degree." http://www.pik-potsdam.de/~stefan/Publications/Other/rahmstorf_climate_sceptics_2004.pdf Prokaryotes (talk) 22:42, 12 April 2014 (UTC)
 * The dubious and flawed research by Veizer and Shariv, claims: "The drifting apart of solar activity and terrestrial temperature development observed since 1980 is due, according to Veizer and Shaviv, to the fact that our solar system is currently leaving teh Sagittarius-Carina arm of the Milky Way" (Source from above). Prokaryotes (talk) 22:48, 12 April 2014 (UTC)
 * Even if Spinning  Spark  claims he is not a "nay sayer" as he puts it, he is currently protecting their debunked claims. Prokaryotes (talk) 22:49, 12 April 2014 (UTC)
 * I am doing no such thing. There is nothing in the article about their ideas on recent and short-term effects.  It is not discussed in the article at all so in what way am I supposed to be defending that.  To reiterate, the passage I restored is critical of Veizer and Shaviv, not supportive.  Even if there were some problem with the accuracy or balance of the text, wholesale deletion is not the answer.  It is just astonishing to me that the whole global warming debate has not only become so toxic that it is not permissible to even mention that there is a contrary position, but it seems that for some it is not even acceptable to talk about the work of contrarians in an unrelated context.  Spinning  Spark  00:23, 13 April 2014 (UTC)
 * Also, having read through all of The climate sceptics article you linked, in my reading it does not say Veizer and Shariv made those claims. It says Gartner made the claims and cited Veizer and Shariv who subsequently denied it and said he was wrong.  Spinning  Spark  15:45, 13 April 2014 (UTC)

It is important to point out the wrongs and discuss them, and i agree with you on this part, however as pointed out "Paleoclimatology, is not the right place for this". The studies on a supposed connection with cosmic rays and climate are not credible, therefore it is not acceptable to mention them on an entirely different page. Or to construct a section around the discussion of CR's. This post explains in detail why: A critique on Veizer’s Celestial Climate Driver. Read the "Some final remarks" of this post, in response to your last argument that the authors have what you call a "contrary position". In a nutshell, their paper is inconsistent, because it doesn't show a long-term trend in the CRF-data. It has nothing to do with climatology, because there is no established connection and even if there somehow is a connection, it is considered negligible. No paleoclimatologist is studying the paleoclimate based on cosmic rays. The authors you are defending are no paleoclimatolgists or climatologists. The study was not peer-reviewed by climate scientists.

Summary
 * Content scope (long term climate drivers) is already covered in another article
 * Arbitrary, and therefore confusing section timeline
 * The discussion about cosmic rays is not relevant for the article, because it is a flawed study fringe theory. Prokaryotes (talk) 12:25, 13 April 2014 (UTC)


 * I cannot agree that this material does not belong. Paleoclimatologists have no way of measuring archaic temperatures directly; they have to use proxies.  In order to use a proxy one has to have a theory of how temperature is driven by that proxy (or vice versa).  A discussion of ancient cliamte drivers is therefore more than relevant to this article, it is central to it.  If we cannot agree on that basic point can I suggest opening a RFC to get more opinions.
 * Veizer is a secondary issue to whether the section should even exist or not, but I do wonder if that is not the thing that has made this such an issue. In any event, we really need to keep these two things separate to avoid a confused discussion.  Most of your arguments against Veizer are replying to things that are not in the article.  The link to the RealClimate blog is criticising Veizer's 2005 paper (which is not in our article) mostly with respect to the effect of CRF on recent climate change (which claims are not in our article) and on longer term trends (hundreds of millions of years, which are in the article) the blog either voices a slight "maybe" or "undecided".  In fact, the only claims of short term effect of CRF are by Svensmark, and I agree that these are in entirely the wrong section and may well amount to WP:UNDUE.  Spinning  Spark  15:45, 13 April 2014 (UTC)
 * Cosmic rays are not climate proxies. The sub sections "Long term (108 to 109 years)" and "Very long term (109 years or more)" of Controlling factors use content from Veizer 2003 and 2005. The discussion you suggest, for cosmic rays belongs on the Fringe Noticeboard. I've already suggested to you several times that we could add a section about forcings. Prokaryotes (talk) 16:00, 13 April 2014 (UTC)
 * Being wrong is not the same as fringe. Fringe to me means "largely ignored by the mainstream" and Veizer has certainly not been ignored.  I offer no opinion on whether he is right or wrong, but he certainly meets our criteria for inclusion.  Something so widely discussed is very likely to attract readers to the article looking for information.  I am fine taking this to the fringe noticeboard if that's how you want to resolve it.  I beg your pardon on the 2005 paper, I had not looked past the long term section.  I don't really understand how a "forcings" section would be different from what we have now.  Are "controlling factors" not forcings?  Spinning  Spark  16:14, 13 April 2014 (UTC)
 * I've opened a discussion, here Prokaryotes (talk) 16:35, 13 April 2014 (UTC)

Removed bogus source
Hi All, I came across this discussion and have removed the following source and all statements referenced thereto: This is an EGU abstract. It is not peer reviewed at all and therefore not a reliable source. Particularly for controversial claims. Sailsbystars (talk) 20:26, 14 April 2014 (UTC)
 * , see also online version or online discussion


 * But you have left in the following sentence criticising Shaviv and Veizer's CRF theory which has now made a nonsense of the text. It now sounds like galactic motion is being criticised, which it is not, that is well established. I can't really see what your problem with this is anyway from a RS perspective.  Shaviv and Veizer may not be reliable sources for the cause of long term climate change, but they are certainly reliable sources for information on their own theory.   Spinning  Spark  20:41, 14 April 2014 (UTC)
 * Ahhhh I missed that. I commented it out for now.  BTW, I'm not entirely certain I've got this right.  The Bibcode and doi seem to be pointing at different things, for the source I've listed above (and one of the links is dead).  Sailsbystars (talk) 20:47, 14 April 2014 (UTC)
 * Now you have me confused. Are you saying you only removed the material because you could only see the abstract in the link?  It is still referring to the same article which appeared in GSA Today and the abstract you can see is exactly the same as the abstract in the article.  Spinning  Spark  21:27, 14 April 2014 (UTC)
 * The bibcode page (ADS) says "EGU Abstract" but the doi leads to a "GSA Today" article. This might be reconciled if EGU abstracts were published in GSA today..... but given that EGU=European Geophysical Union and GSA=Geology society of America that doesn't make sense.  So honestly, I'm a bit confused here too.  I'm wondering if the ADS page has the wrong info.... in which case I'm wrong and you or anyone can go ahead and revert my edits.  GSA Today would be a reliable source, but EGU abstracts would not be.   Sailsbystars (talk) 21:36, 14 April 2014 (UTC)
 * The Bibcode is wrong. Probably been inserted by some faulty citation bot (or it is linked wrong in some database). The GSA Today paper has always been the one referred to. --Kim D. Petersen 12:01, 15 April 2014 (UTC)
 * Also, another potentially useful source (which seems to be quite legitimate and cited by people who aren't involved in the climate debate):


 * Might make sense to restore the text, but swap the source if the source supports the same claims. Sailsbystars (talk) 20:51, 14 April 2014 (UTC)
 * I've removed false statements and unrelated content (Veizer et al), per IPCC definitions and extended the info a bit. The content can now be extended, with the focus on Earth past, for instance with the mention of the "early faint Sun paradox" . Is already part of the article. prokaryotes (talk) 22:20, 14 April 2014 (UTC)
 * A more recent study on the early Sun problem, with peer-review from 2012 can be found here http://arxiv.org/abs/1204.4449 prokaryotes (talk) 22:45, 14 April 2014 (UTC)
 * Yeh, the cosmic ray stuff is pretty dated, but there is a mention of it in the review paper you've listed which basically says "It didn't work out." Sailsbystars (talk) 01:32, 15 April 2014 (UTC)
 * Yes. Additionally, i learned that there is Cosmogenic radionuclide dating https://en.wikipedia.org/wiki/Surface_exposure_dating#Cosmogenic_radionuclide_dating However, this has nothing to do with cosmic rays causing global warming/climate change. And here is a discussion about galactic cosmic rays (GCR) and variations in Earth’s cloudiness - See more at: http://www.realclimate.org/index.php/archives/2012/12/a-review-of-cosmic-rays-and-climate-a-cluttered-story-of-little-success prokaryotes (talk) 12:47, 12 May 2015 (UTC)
 * Yes. Additionally, i learned that there is Cosmogenic radionuclide dating https://en.wikipedia.org/wiki/Surface_exposure_dating#Cosmogenic_radionuclide_dating However, this has nothing to do with cosmic rays causing global warming/climate change. And here is a discussion about galactic cosmic rays (GCR) and variations in Earth’s cloudiness - See more at: http://www.realclimate.org/index.php/archives/2012/12/a-review-of-cosmic-rays-and-climate-a-cluttered-story-of-little-success prokaryotes (talk) 12:47, 12 May 2015 (UTC)


 * Neither WP nor Realclimate is a suitable source. The cosmic ray issue is tricky in nowadays short term changes, but still being of interest (e.g. at CERN). it is quite feasible and powerful in the earlier geological time frames and as well for the faint young sun paradox. That said, no reason to delete valid stuff. Serten 17:31, 12 May 2015 (UTC)

Third Atmosphere
Question on the third atmosphere section. The article makes mention about the peak oxygen levels during the Carboniferous period. Since oxygen levels were so much higher during this period than they are today, what impact did this have on animal life during that period? Since periods with high levels of oxygen in the atmosphere are associated with rapid development of animals, did this correspond to this time period? If so, what sort of evidence do we have about these animals. Also, what is the evidence and how do we know that the oxygen reached its peak during this period? Anth1112 (talk) 14:49, 18 February 2017 (UTC)

Mechanisms
The article discusses the process of chemical weathering when the weathering sequesters CO2 by the reaction of minerals with chemicals, and it specifically mentions silicate. Isn't this one of factors that goes into the creation of sand near beaches? Or am I thinking of something else? Does this chemical weathering have anything to do with the formation of sand? If so, would it be a good idea to mention that in the article since sand is one of the most common substances on Earth's surface and its use has many environmental impacts? Anth1112 (talk) 14:57, 18 February 2017 (UTC)

Lost data
What can we learn from the dangers of proxy data? The troubling thought is, with so much human interference, we are losing out on valuable data that can be used to warn us what is to come in the future. Of all the human interference, whether it be with pollution's or melting of ice sheets, you have to imagine the amounts of proxy data that have been lost and the information we could have gained from that.

Centuries from now, what will our atmosphere be composed of? Can we tell by using proxy data from the past to predict the future of our atmosphere? User: vogelj265 (talk) 19:43, 21 February 2017 (UTC).

Credibility of References
Is each fact referenced with an appropriate, reliable reference? ... Yes, to my knowledge.

Is everything in the article relevant to the article topic? Is there anything that distracted you? ... Content is relevant.

Is the article neutral? Are there any claims, or frames, that appear heavily biased toward a particular position? ... Article has neutral position.

Check a few citations & references. Do the links work? Is there any close paraphrasing or plagiarism in the article? ... One citation's hyperlink led to an error page. "Recovery from the most profound mass extinction of all time," did not lead to credible page.

- Sheasby45 (talk) 01:05, 22 February 2017 (UTC) -

Evaluation and Two Questions
After reading this page I have several suggestions for making it better. I noticed that there are no specific sources listed in the sedimentary proxy section of the article which makes me question its credibility/reliability. Adding in the source here would be a smart move. Secondly I think that EPICA should have been explained as it was mentioned in the ice cores section of the article instead of under the limitations heading at the bottom of the article. Lastly, in the Earliest atmosphere section the author should change their wording form "would have been" to "was". saying "would have been" In the context of the section almost makes the author seem unsure of their own information and saying "was" sounds more sure, giving the readers a stronger sense that what they are reading is correct. I also have questions after reading this article. In the 3rd atmosphere section I am wondering why it was necessary to add in that there was "enough oxygen for rapid animal development". To me it seems off topic and I would like to know why the author wanted to include it. Secondly I was wondering why the Precambrian Climate section is essential to the article. While reading it I was confused on how it related to the definition of paleoclimatology. In my opinion it took away from the focus on what paleoclimatology is and was distracting to read. I don't know if I'm missing something though, hence why I wanted to ask for clarification and to gain some background knowledge about the section and its purpose in the article as a whole. ChloeSmeltzer (talk) 22:41, 22 February 2017 (UTC)

Evaluation of Article
While first reading the article I was surprised by the lack of references that were given in the initial description of what Paleoclimatology is. I felt like there were so many facts given that should have been backed up by references and weren't. A good thing about this article was the fact it seemed very neutral over the topic.So certain biases on Paleoclimatology were not distracting. When looking at the reference links they all worked and deemed to be from credible sources which made me feel better about the wiki article I was reading.

Questions: 1. How can paleoclimatologists ensure that their data is correct and also associated with the time period they say it was associated with? 2. With the melting of glaciers will traces of our atmosphere last in ice cores just as traces of atmospheres from thousands and thousands of years ago lasted in the ice cores we dug up?

Pawlak.30 (talk) 22:54, 22 February 2017 (UTC)

Article Critique
While the article cites reliable sources, the most recent source is from 7 years ago (2010) and they go back to 1979. I'm sure more peer reviewed articles with up-to-date information regarding new findings from paleoclimate proxies have been released, which could keep the article itself more reliable and informative. (Is any information in the article that is out of date? Is anything missing that could be added?) Furthermore, I noticed that the history section is only comprised of once sentence. Even though the article does provide links for readers to access more information about the historical aspects of paleoclimatology, I think providing a more collective account of all relevant information would be more useful than following multiple links to locate answers to questions one might ask. (Are there viewpoints that are overrepresented, or underrepresented?) On a positive note, I noticed that each subtopic is separated adequately in order for readers to understand more about each particular proxy. The article also includes many links (like "climate") in order to further readers' understandings regarding paleoclimatology. Kadeynelson (talk) 22:55, 22 February 2017 (UTC)

Citation Issue
The article has many helpful links to other wiki articles, but the subsections Ice, Dendroclimatology and Sedimentary Content under "Reconstructing Ancient Climates" need peer-reviewed citations. Are there any current sources that could be used to verify this information? Another issue with sources are that links 1, 4 and 5 are not available. Could the information referenced in those sources be replaced with accessible sources? FuSha (talk) 20:28, 22 February 2017 (UTC)

Article Critique-Geography 3900
The information featured in this article all appears to be relevant to paleoclimatology. The article covers various aspects of Earth’s systems that scientists research in order to learn more about the makeup of the atmosphere in the past. The information itself was not distracting to me, however, I do have one critique. The article only has brief descriptions in its subsections, and nearly all of them require the reader to go to another article. I think that while it makes sense that there is more information elsewhere, if a reader is just trying to get a general idea about a topic, it can be frustrating to constantly have to jump to other pages in order to get more substantial information. The page is not locked, which has its pros and cons. On one hand this allows for paleoclimatology experts to easily expand upon the article, but on the other hand anyone can edit who thinks they know something about the subject. These people could believe they have correct and accurate information when in reality their sources could be unreliable or outdated. 140.254.180.92 (talk) 02:32, 23 February 2017 (UTC)

Invasion of the student editors
It's good that the student editors have gotten involved and offered some feedback on the talk page. Only one of them has done any editing on the article itself, though, and anyone can use a search engine to find reliable sources. Wikipedia policy says that "Wikipedia is run as a communal effort. It is a community project whose result is an encyclopedia... Be bold and edit the pages to add information or correct mistakes."

The article has no single "author", and anyone can edit it and fix its flaws. The energy that the students have put into making suggestions (in what comes off as a rather admonishing tone) could have been used to improve the article in the very ways they suggest. We need all the help we can get.

PS: Please remember that the talk page is for discussing the article, not for general discussion of its subject. Best regards, Carlstak (talk) 02:50, 23 February 2017 (UTC)

Article Critique: Geog 3900
I question how reliable this article is because so much of the information goes without citations. Under the heading "Reconstructing ancient climates" the sections "Ice," "Dendroclimatology" and "sedimentary content" there are zero citations. The information may be true, however no one can be sure without reliable references. However the citations that are utilized seem to be reliable (with the exception of note 5 that does not show any information).

It seems like this page has a good skeleton but could still use a lot of editing and citing to make it more reliable.

For purely aesthetic purposes this article should have a picture toward the beginning of the article. Perhaps a picture of an ice core? 4timothyduncan (talk) 06:10, 23 February 2017 (UTC)

Article Critique GEOG 3900
There was nothing that overall distracted me in this article. My first critique would be that I have would be that some information is brief and should be touched upon more. For example, I feel that there is more information that should go under the History or paleoclimatology. Things such as what began the search into paleoclimatology and who began the study. Another critique that I have would be that there is not a reference in every subtopic. In the training it describes that there should be a source that goes into each subtopic/paragraph/section. My last critique would be that the sources are not all up to date. There are some sources that are from 2012 but the ones that are from for example 1983 should be updated. Tazia712 (talk) 07:04, 23 February 2017 (UTC)Natazia Lewis

Lots of critiquing by students, but little contributing
It appears that the students were assigned to critique the article, but that actually contributing was not part of the assignment. Not much value in that. Carlstak (talk) 12:22, 23 February 2017 (UTC)
 * Not to us, but seeing what class assignment contributions usually do, a sigh of relief may be justified. If they are going to edit they will normally do so later, as part of a timetable that should be set out somewhere. But the trend on WikiEd seems to be to critique rather than edit much, perhaps because so many student edits got reverted en masse, often deservedly. Johnbod (talk) 13:18, 23 February 2017 (UTC)
 * Ha. True, true. Duly noted. My impression is that professors who make these assignments spend little time ensuring that students are aware of WP policies and good practice before letting them loose to wreak havoc. Thanks for the reminder. Carlstak (talk) 14:16, 23 February 2017 (UTC)

Article Critique for GEOG 3900 Everything in the article seems relevant to the topic of paleoclimatology. The sections are all related to paleoclimatology and contributed to a deeper understanding of paleoclimatology’s significance in the context of climate change. The article discusses how paleoclimatology allows scientists to reconstruct past climates, describing several methods as well as identifying the limitations of these methods. That being said, the section on climate forcing could be better explained in the context of paleoclimatology. I understand that climate forcings are a part of why climates change, but I think that this connection between climate change, paleoclimatology, and climate forcing could be better articulated.

For the most part, this article portrays neutral viewpoints, however, the limitations section is too small. There are certainly more than just limitations related to ice cores, which is what the section describes. The limitations section should be as long as possible, and it should detail the limitations of all of the methods described in order to be thorough. --Marissarosek (talk) 23:59, 1 March 2017 (UTC)Marissa Kelly, The Ohio State University

Geog 3900 Article Critique
While this article seems pretty reliable, there are a good amount of facts and information that are not referenced. The history section is very short with only one sentence and could use some more background information on early techniques or ideas on the topic and how they have progressed since then. Many of the sections in the article briefly talk about the topic of that section and then list links to an article that covers that topic more specifically. It would be more convenient if some of the shorter sections that provided links contained more information on that topic. --Ekorte331 (talk) 02:55, 2 March 2017 (UTC)

Article Critique
This article was very interesting and informing. The first thing I noticed, however, when scrolling down the page was that the History section is very short. It’s only one sentence. There are links to main articles in the section, but a better summary of the other articles could give me more information directly on the page. I like the way the Reconstructing Ancient Climates section was broken down into the different proxies used to study Paleoclimatology. I made it easy to scroll through and see the different sections. There are plenty of links to related topics on the page, but some sections don’t have any citations at all. Then Sedimentary Content page does not have any citations and the Sedimentary Facies links to another Wikipedia article with no relevant citations. There are plenty of graphs and charts to catch the eye. As someone who learns much better visual than by reading, they really give something to learn from.Pasi.nick (talk) 03:50, 3 March 2017 (UTC)

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Critique/commentary
While all the information on this page is relevant to the topic, the information that is present is not always adequate. A few sections (eg. The introductory sentences, "climate forcing, and "first atmosphere") could use some more information. The section about climate forcing is a bit awkward to read - it has odd grammar and a couple typos. The first few sentences of the whole article do not give a great overall picture of the topic. Overall, it would be beneficial to Wikipedia's target audience to make the article a little easier to read for the average person. The extensive use of field-specific vocabulary, while necessary in some instances to accurately describe a concept, detracts from the ability of an average reader to comprehend the material. Cfaramarzi (talk) 06:39, 6 February 2019 (UTC)

Please don't hesitate to edit the article instead of critiquing it. Femke Nijsse (talk) 18:30, 25 August 2019 (UTC)

Atmospheric pressure
Surprised to see there is nothing about the variation in atmospheric pressure.

Here are a few links, but they contradict each other
 * Earth’s atmosphere before the age of dinosaurs suggests early atmosphere may have been much higher in pressure though it does raise the possibility that it was also low in pressuer, says pressure 100 million years ago is probably a fair bit higher.
 * Earth's air pressure 2.7 billion years ago constrained to less than half of modern levels suggests an upper limit of 0.5 atm and likely 23% of normal 2.7 billion years ago
 * Earth’s ancient atmosphere was half as thick as it is today - sciencemag account of the same research

I think it would be a useful new section. Robert Walker (talk) 06:15, 1 March 2018 (UTC)