Talk:Proxy (climate)

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Shouldn't the O-18/O-16 ratio be

O-18 to O-16 is 2005 * 10-6 rather than 106? --Vsmith 15:50, 16 Sep 2004 (UTC)

(William M. Connolley 17:36, 16 Sep 2004 (UTC)) I think you're right. I've changed it.

Merge note

Don't merge - see discussion on Talk:Proxy (statistics). Vsmith 00:34, 21 March 2007 (UTC)

1000% or 100%?

The aticle states 1000% in the formula for delta. Shouldn't it be 100%? Dan Gluck (talk) 08:43, 23 October 2009 (UTC)

It is ugly and I don't have a ref handy but it says "1000‰" not "1000%" William M. Connolley (talk) 16:45, 23 October 2009 (UTC)

Borehole question

I don't follow the explanation of how past temperatures can be discovered from boreholes. The article states that temperatures on the surface send "waves" into the earth. Is the reader to understand that at a certain depth, the temperature ar that depth is correlated with the surface temperature from a certain time period in the past, and that a different depth, the temperature would be related to a different time period in the past? What sort of depth per hundred, or per thousand years, is involved? What sorts of temperatures are involved? What effects from different types of rock?

This sounds really interesting, so I would like to know quite a bit more about it. --Janice Vian, Ph.D. (talk) 23:06, 6 December 2009 (UTC)

If you pretend the temperature of the interior is fixed, and then suppose that the sfc T was too, then you would get a linear variation of T with depth. Now, suppose you instantaneously change the sfc T: you get a slow propagation of a temperature signal into the interior, as the system adjusts to a new linear profile. The response is -exponential with depth, so can be very slow. But since the system doesn't adjust immeadiately it does mean that different depths to some extent preserve a surface T signal from different times, but there is no 1-to-1 correlation of depth A representing time B. Think of it like the mixing that occurs in going from space to time domains in fourier analysis, if you know that. So, with a given starting point and a given sfc T history, the borehole T profile can be predicted moderately accurately. Unfortunately, we have the reverse problem: a given borehole T profile, which needs to be "inverted" to produce a sfc T history. In theory, the two items of information if measured to infinite resolution are equivalent. Since there are uncertainties in the borehole T's (small; ~1/00th's of oC from memory) it is not possible to exactly reconstruct the sfc T history, and the further you go back in time the worse the temporal resolution gets (for example, it may just about be possible to see the last ice age, but only very broadly). I don't have a good ref to hand, but [1] (yes, I know, its by me) brings out some of the issues William M. Connolley (talk) 00:12, 7 December 2009 (UTC)

Sourcing; self-published vs a secondary book

This edit removed a secondary source and replaced it with a link to a self-published blog. Per WP's guidelines, reliable secondary sources are preferable. Cla68 (talk) 11:50, 19 July 2010 (UTC)

Please stop your disruption here and elsewhere. It does no good, and your replacing a RS with a non-RS is obviously unhelpful William M. Connolley (talk) 13:05, 19 July 2010 (UTC)
Plimer's book is a terrible source (fringe, non-expert, riddled with inaccuracies) but I think we can do better than RC. I've rewritten the intro with a (IMO) more informative description and a source that should be uncontroversial. -- ChrisO (talk) 19:44, 19 July 2010 (UTC)

comparison?

which proxies have less confounding factors? More closely follow recorded local temperatures. They can't all be equal. Some must be better than others... —Preceding unsigned comment added by 173.67.242.4 (talk) 17:41, 18 August 2010 (UTC)

Fair point. And some reflect different seasons, have different temporal resolution, etc William M. Connolley (talk) 17:39, 19 August 2010 (UTC)

General problems of paleotemperature proxies

We need to add a section re this, which in essence is the difficulty in separating the temp signal from the noisy background. This affects all the temp. proxies to varying degrees. A good place to start, when it's actually published, will be McShane and Wyner 2010 , the most recent review. --Pete Tillman (talk) 20:37, 20 August 2010 (UTC)

Problems should be mentioned. Your preference for M+W is perhaps indicative of the problems we might have in doing one William M. Connolley (talk) 18:47, 3 October 2010 (UTC)

Boreholes

Not sure that they should be in here, as they aren't a proxy per se: you are measuring actual temperature, through a filter of thermal diffusivity. Awickert (talk) 13:42, 3 October 2010 (UTC)

Aha, but they are a spatial proxy for a temporal signal :-) William M. Connolley (talk) 18:44, 3 October 2010 (UTC)
Very cute, but seriously isn't that a bit of a stretch? Your logic makes a chart recorder a "spatial proxy".
The 2003 book "Borehole Climatology" by Bodri and Cermak says "Borehole paleoclimatology enables climate reconstruction of the past several millennia, unlike proxy methods provides direct past temperature assessment, and can well broaden the areal range to the remote regions poorly covered with meteorological observations."
Boreholes aren't proxies, they're even more direct recorders of temperature than chart recorders. Vaughan Pratt (talk) 05:31, 5 August 2014 (UTC)

Boreholes - Limits for Deep Holes

I think you should mention that temperature reconstructions are usually only made upto a depth of about 400 m. In 1997 Shaopeng Huang and Henry N. Pollack published a reconstruction using measurements from a 2 000 m borehole http://www-personal.umich.edu/~shaopeng/97GL01846.pdf. Later, realizing that due to lack of knowledge concerning porosity, rock type, geothermal flow, etc. a proper temperature reconstruction for such a long time range 20 000 years(!) was not possible, they retracted the paper. — Preceding unsigned comment added by 84.176.205.240 (talk) 16:45, 8 January 2012 (UTC)

Oldest known records

Can we add the oldest known records? Prokaryotes (talk) 20:22, 9 April 2014 (UTC) Suggestion(see editor for sources):
The oldest known climate records are from the Barberton Greenstone Belt South Africa, and Pilbara Craton in Australia which helps to understand Earth's early atmospheric oxygen content 2.3 billion years ago.[1][2] The first glaciation as evidenced in the Pongola Supergroup records from South Africa.[3]

The NYT doesn't even mention the word "climate" William M. Connolley (talk) 20:31, 9 April 2014 (UTC)
See this book tinyurl com/qxdscdx and this recent article http://www.sciencedaily.com/releases/2014/02/140219133331.htm (doi:10.1038/nature13068) Prokaryotes (talk) 20:52, 9 April 2014 (UTC)
Which barely mentions the word. This isn't really a climate proxy in the usual sense. Its so unimportant that our article doesn't discuss it. Why should it be in the lede? William M. Connolley (talk) 07:05, 10 April 2014 (UTC)
Notice that paleoclimatology lists rocks as climate proxy, and ofc it can be mentioned somewhere else other than in the lede. Prokaryotes (talk) 14:18, 10 April 2014 (UTC)
For a broader discussion of earliest climate proxies, see http://arxiv.org/abs/1204.4449 (PDF download link on the right sidebar) Prokaryotes (talk) 00:58, 12 April 2014 (UTC)

Need more recent sources

The sources used all seem to be older than five years old; at this point in time I think it would be more than beneficial to update the page and add some more resources and facts, because there are bound to be new developments in all the fields mentioned. Additionally, there appears to be some discrepancy involved in how much information is given to each topic, and it should be more equally distributed. The links provided seem to all come from reliable sources, and they all seem to work, with the exception of the CNN article which just takes me to the homepage of CNN and not the article that it is referencing. They do not appear to be biased; there are sources such as the Merriam Webster dictionary, which is notably neutral. Ugoliniaw (talk) 21:22, 26 February 2017 (UTC)Ugoliniaw

Edited by Alice?

Isotope section currently states " where D denotes deuterium, i.e. hydrogen with an extra neutron" Deuterium does not have an EXTRA neutron, it has one neutron. Tritium does not have extra neutrons, it has two neutrons. AnnaComnemna (talk) 17:53, 6 October 2016 (UTC)

Diatons and Forams

This article doesn't mention diatons and forams. The oxygen isotope ratios in their shells are used as proxies for temperature. Also the distribution of the species of these and other sea creatures preserved in the sediments, since species have optimal conditions. Also warmer conditions have more of them. Proxies for ocean temperatures and conditions. See Paleoclimate. They could perhaps be mentioned in the section on lake and ocean sediments. Robert Walker (talk) 16:16, 3 December 2016 (UTC)

I decided to just be bold and added it in Robert Walker (talk) 16:25, 3 December 2016 (UTC)

Reference 13 and Under-representation

I noticed that reference 13 links directly to CNN's homepage, and I am wondering if this source would be considered biased? Additionally, I am not positive, but are any of these sections under-represented? I noticed that the "Fossil Leaves" section has much less content than the "Boreholes" section. Cunningham.734 (talk) 01:22, 7 February 2017 (UTC)

Corals

Reference 15 under corals no longer works, or at least it doesn't direct you to a reference (Jriley97 (talk) 18:56, 16 February 2017 (UTC))

Paraphrasing and Wording

Nitpicky I know but the first sentence, specifically "In the study of past climates ('paleoclimatology')", is worded quite closely to the reference material. Perhaps rewording or reorganization of the sentence would help. (Jriley97 (talk) 19:02, 16 February 2017 (UTC))

Evaluation

I noticed that there were not equal amounts of information to describe the various types of proxies. There is significant information to describe boreholes, but minimal information on pollen grains and psuedoproxies, thus these viewpoints should be expanded upon. In addition, some of the sources listed have broken links. When I clicked on source 5, I was directed to a "missing page" sign. Source 7 takes me to CNN's homepage, but when I searched for the actual article listed, I could not find it. Many of the sources are also not reputable. The most reputable sources on this page are government documents, but many of the most widely cited sources in this page are not credible. For example, source 1 takes me to Unisci.com, which when looking at that source, does not appear to have any credentials in terms of explaining facts. The credible, peer reviewed sources cited in this page are rarely used. (Steiner.260 (talk) 20:09, 17 February 2017 (UTC))

Critical Thinking

Some of these climate proxy examples could be expanded on further; for example, Pseudoproxies and Pollen Grains have a have significantly less information than other examples, such as boreholes. Additionally, some of the sources are either nonexistent or not very credible. One source led me to a "missing page", and another led me to a page stating that the information previously located there was now located somewhere else. There are far less peer reviewed articles cited in this article than articles from websites that have no credentials. Also, there are many specific articles just about Boreholes, and most of the other climate proxy examples do not have their own specific source - adding more specific information from other sources may solve the first problem I listed. Kbrown218 (talk) 19:22, 20 February 2017 (UTC)

"Speleothems"

There was a mention at the beginning of the this article of Speleothems reading as, "Examples of proxies include ice cores, tree rings, sub-fossil pollen, boreholes, corals, lake and ocean sediments, and carbonate speleothems.". However, after listing all of these proxies, the article excludes the Speleothem proxy from any other mention. For example, there are entire sections on ice cores, tree rings, pollen, boreholes, corals, lake and ocean sediments, but no mention of carbonate speleothems after this initial mention. The speleothem article is linked within the single sentence that speleothems were mentioned in the Proxy (Climate) article.

It may be useful to insert this section from the Speleothem article into the Proxy (Climate) article. Would there be any reason for us not to include Speleothems into the article?

--Rebecca.salamacha (talk) 21:54, 20 February 2017 (UTC)

Ice Core Map Link is Broken

Within this article there is a sentence at the end of the "Proxy" sub-article under the "Ice Cores" section that reads as follows, "Location maps and a complete list of U.S. ice core drilling sites can be found on the website for the National Ice Core Laboratory: http://nicl.usgs.gov/coresite.htm[6]." The link for the National Ice Core Laboratory is broken and only takes the reader to this page: http://icecores.org/coresite.htm which is a broken web page. This also means that source 6 listed under references is broken. Should we remove this sentence and reference?

--Rebecca.salamacha (talk) 22:04, 20 February 2017 (UTC)

Age of some sources and lack of 'Fossil Leaves' information

The 'Fossil leaves' section is extremely short compared to each other Proxy example. There is only one source for the entire section, however it is one of the more recent sources (2014). Also, at least half of the sources were published over 10 years ago, and in a rapidly changing field like science there must be more up to date information on these topics that could be used instead as some of these could be at risk of becoming out of date. CatherineKailua (talk) 22:55, 20 February 2017 (UTC) CatherineKailua (talk) 22:56, 20 February 2017 (UTC)

Source links broken and more neutral references

A few of your references are related back to articles that seem to make a claim on climate change. Although the information you received and put into the article does not make a claim towards climate change or your viewpoint on the subject matter, some readers may think that your ideas may be showing a bias viewpoint to climate change. Reference 13 ( Environmental News Network staff. "Borehole temperatures confirm global warming.") and also reference 4 ( "Borehole Temperatures Confirm Global Warming Pattern.") I also noticed that some of your references do not work anymore. I would recommend to either remove the reference and the information that is associated with the article or find another reference that can take the place of this article as well. Reference 15 ("Coral Layers Good Proxy for Atlantic Climate Cycles.") does not work anymore.

user: Alexwheeler711 —Preceding undated comment added 18:14, 21 February 2017 (UTC)

References contain some missing links and older sources.

Some of the links for the references are no longer working or active (references #6, #13, #15) and reference #1 is the same as reference #19. Some of the references used here are from older sources (early 2000s) and the article would benefit from being more up to date to stay relevant with current information.

Jtra1n (talk) 21:11, 21 February 2017 (UTC)

Are the references used reliable?

I noticed that many of these articles do not appear to be peer reviewed. Will this effect some people's opinions on the topic if unreliable sources are used? Also, in the article it does not seem to state directly that proxies are uncertain measurements and not including that in the article seems misleading. Teeters.32 (talk) 23:21, 21 February 2017 (UTC)

General Questions

Why were certain proxy data types or techniques talked about on the page while others were just included in links? Does it have to do with how effective they are? Many of the sources are dated from 2000-2009 (with the newest source dated 2014). Are there any findings or techniques in recent years that could be relate able to this page?Ardenholden (talk) 02:03, 22 February 2017 (UTC)

Currency and Relevancy

1. Is any information in the article that is out of date? Is anything missing that could be added?

All but one of the sources are from 2009, and there is one from 1988 about tree rings and dendrochronology. The sources are approximately eight years and twenty-nine years old respectively. Over this time period, there has been further development and research into proxies, and more information about them subsequently discovered. This article neglects more up to date resources. A lot can happen over eight years, let alone twenty-nine.

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

The information in the article is relevant to the topic, and there is not anything that is extremely out of place. However, the section on Boreholes is difficult to follow; and thus this section is indirectly distracting because it is hard to comprehend and relate the information back to the main topic. Further elaboration or a more concise explanation should be considered.

ZacharyFranciscoOSU (talk) 03:30, 22 February 2017 (UTC)

Article evaluation

Although the subheadings discussed where relevant to the topic, there were errors within the article that were distracting. For example, there was an unbalanced amount of information written in comparison to other paragraphs, particularly in the "fossil leaves" and "boreholes" sections; where there is a lack of detail in the former section and an excess of detail in the latter. Also, the "pollen grains" section should be rewritten because there is a lack of flow within the sentence structure.

The majority of the information presented appears to come from relevant and peer-reviewed sources, with the exception of a few areas. One source found in the "proxy" section of the article references a link from a commercial website. Another section, also labeled "proxies" has no references cited and is linked to another Wikipedia page titled "proxy (statistics)", which is irrelevant to the article topic. Finally, there is a lack of adequate citations or citations that are completely nonexistent in multiple sections of the article (e.g. the "tree rings" section), which should be revised. Kayla0013 (talk) 15:52, 22 February 2017 (UTC)

Simplify Definition

Simplify the definition of climate proxies to make it easier to understand. To fully understand this definition I would have to look up the definition of "meteorological measurements". I think a good definition is one that requires little to no previous knowledge, that anyone can read and understand. By this definition it assumes that climate proxies are only physical characteristics, where I remember from class that it can also be chemical. Rdaugherty347 (talk) —Preceding undated comment added 16:23, 22 February 2017 (UTC)

The link for the location maps and ice core drilling sites needs to be updated because the page no longer exist. http://nicl.usgs.gov/coresite.htm Rdaugherty347 (talk) —Preceding undated comment added 16:36, 22 February 2017 (UTC)

Missing information, graphs and images

I would suggest elaborating on many of the topics on this page and adding appropriate graphs and pictures to each proxy section would be beneficial to understanding the topic. Elaborate on tree rings, fossil leaves, and pollen grains by providing details on exactly how the data collected from these proxies is correlated to past climate.Rdaugherty347 (talk) —Preceding undated comment added 16:53, 22 February 2017 (UTC)

Citation and Viewpoint Problems

Several of the sources in this article were no longer hyperlinked to a functioning website. For example citations #6 and #15 were no longer linked to an article. Other citation problems include the lack of citation. Specifically in the section about tree rings because there are zero citations in this section to verify the information provided. Other sources are fairly dated. For example, citation #16 was written in 1992, in a fast pace, innovative field such as climate change I am sure there are more recent sources that discuss this topic in a more relevant manner.
Some views were under-represented. For example, there is not much discussion on the variability and uncertainty from these proxies. Proxies are an essential tool while discussing climate change, but the article would be strengthened by discussing possible counter arguments and view points.Kas dalton (talk) 21:18, 22 February 2017 (UTC)

Understated

The section about fossil leaves has a good source but needs a deeper definition of the process. A second source would strengthen the background of this section. The pseudoproxies section could also use a rework to simplify the material and fully portray the function of what pseudoproxies actually do. Jordan1327 (talk) 01:41, 23 February 2017 (UTC)

Tree Rings and more.

There is a lack of discussion about tree rings. The article gives a lot of scientific and factual information about every other proxy, but when it talks about tree rings it is very vague. It should add more about what that proxy has to do with climate. It says larger spaces are more favorable for growing while smaller ones are not. It should describe and reference approximate distances that are "large" and "small" and what kind of climate is associated with each.

"Borehole temperatures in Greenland were responsible for an important revision to the isotopic temperature reconstruction, revealing that the former assumption that "spatial slope equals temporal slope" was incorrect." This sentence does not have a reference and it is scientific information is saying something is incorrect.

Cstarn2017 (talk) 01:43, 23 February 2017 (UTC)

Lacking in-text cites

The sections for "tree rings" and "proxies" do not have a single in-text citation. I see that there's a reference to an original article for both of these, but unsure on if they should still be cited with a footnote in the paragraph. Connorlemons (talk) 06:01, 23 February 2017 (UTC)

Boreholes Final Statement

The Boreholes section ends with this statement: "Borehole temperatures in Greenland were responsible for an important revision to the isotopic temperature reconstruction, revealing that the former assumption that "spatial slope equals temporal slope" was incorrect." I believe this needs to be cited with a footnote, as it is a direct quote. Connorlemons (talk) 06:27, 23 February 2017 (UTC)

Citations needed

As explained in the Wiki training modules, a good goal to set for any article is to include a citation of sources in nearly every paragraph. However, there are a significant number of claims that lack a citation, and entire paragraphs go without. I think a citation should be added after the first paragraphs definition, in the Proxies subsection, and the tree rings subsection, as these sections all lack citations. On a positive note, the citations that are part of this article are mostly well-cited academic journal articles or textbooks written by scientists respected in their fields. Many links are provided and working well. Beccam51 (talk) 14:14, 23 February 2017 (UTC)

Is the article neutral? Are there any claims, or frames, that appear heavily biased toward a particular position? The article itself is very neutral, it gives a history of proxy climate, but does not allow any opinion or politics into the article. It also explains many examples of Proxies like tree rings, coral, and boreholes. Giving a fact orientated review on each faucet.

Check a few citations & references. Do the links work? Is there any close paraphrasing or plagiarism in the article? I checked many of the resource links and they all came from reliable sources, some being from the Intergovernmental Panel on Climate Change, which is a well established group. And the information that was taken from these sources did not contain any close paraphrasing or plagiarism. BeckyDye (talk) 16:15, 23 February 2017 (UTC) Rebecca Dye

CNN Article

I clicked on a CNN article, and this link was dead, Environmental News Network staff. "Borehole temperatures confirm global warming." CNN.com. 17 Feb. 2000. 7 Oct. 2009. Also I don’t think that CNN was a good source for a Wikipedia article.

Hoytnina (talk) 21:14, 23 February 2017 (UTC)hoytnina

My evaluations and two questions about proxies.

I think that the page is informative as well as explains the idea of a proxy and how it applies to science appropriately. I also found that some of the sources used as references were expired, or no long linked to the information used on this page. The sources that did work either did not have a date, or were several decades old. I agree with a lot of people that this is an ever changing science, and while the core material might not change, the use of it today as well as newer discoveries using it should be included on this page.

So I have two questions that could help bring more to the page. What further data can we find about proxies in terms of how they are used today? How are proxies being affected by climate change or global warming, and what can they tell us about the past and present?

ZOSUman4 (talk) 02:54, 25 February 2017 (UTC)

Lake and Ocean Sediment--diatoms and forams critique

The Wikipedia article read "diaton;" however, the correct term is diatom. I went ahead and made the spelling correction on the article.

Additionally, the source for the information in this paragraph is not a peer-reviewed source, but an article by a single Earth scientist. A more reliable source for information on the use of diatoms and forams as climate change proxies may be an article I found by the Proceedings of the National Academy of Sciences. --Meavefryer (talk) 20:17, 25 February 2017 (UTC)

Defining Proxy Examples

As someone who is new to the subject of using proxies as measurements, I would recommend defining some of the proxies immediately in each section. For example -- boreholes -- I did not know what this is until the end of the section. Information loses meaning because I am unsure what a borehole is; I am focusing more on definition than information. — Preceding unsigned comment added by AlisaKae (talkcontribs) 21:28, 28 February 2017 (UTC)

Understandability

Besides obvious things like lack of details and lack of sources, this article violates one of the main rules of wikipedia: information needs to be accessible to the general public. I felt like the section entitled “Water isotopes and temperature reconstruction” needs to be redone to where it can be understood by a non scientist. None of the equations are explained and as a non-scientist myself, I do not know what was going on in that section. One good thing about the article, however, is that it is not locked and the things that need to be fixed are not major. Rpwis (talk) 02:47, 2 March 2017 (UTC)

Article Critique GEOG 3900

1. Firstly, there are several citations that are no longer available, such as references six and fifteen. I also noticed that the thirteenth reference simply takes you to the CNN homepage. In addition, there are some out of date articles that date back as far as 1984. There is no issue with the out dated articles, but it may be a good idea to maybe find updated information that can can give more information and give a more in-depth understanding of water isotopes and temperature reconstruction. Aside from these few references mentioned, the majority of the sources seem accurate, unbiased and relevant to informing the reader. 2. The section that I felt needed the most work was the Pollen Grains section. The current flow of the sentence sounds awkward and seems more skewed towards listing off facts as opposed to insightful thought surrounding the topic. I think the main issue is that there is a lack of backing information on the Pollen Grains section, which leads to the awkward flow. More information can be found surrounding this idea, which would make it easier to write about in detail. Last note, maybe the flow could sound better if there were more sentences combined. Gagliardi.23 (talk) 04:19, 2 March 2017 (UTC)

Evaluation//Suggestions

Almost every sentence either ends with a source where it can can be found or specific words are linked to sources with more about that specific topic. The article was to the point and did not distract me from my specific search ‘climate proxies.’ The article correctly keeps a general stance on the subject and does not include opinionated statements. Bias is not in question with this article. Sources of the article were not opinionated and neither bias. Climate change is mentioned in some of the titles of sources, but they create no arguments and simply talk only about the facts. When they put together all the examples of proxies and listed them with a few paragraphs about what they were I felt that some were overrepresented, like boreholes and ice cores and others underrepresented, such as fossil leaves and pollen grains. The article did an excellent job avoiding plagiarism. After checking four different sources listed and reading, I felt that the editors did an accurate job of representing the references. — Preceding unsigned comment added by Rachel.stack4 (talkcontribs) 18:48, 2 March 2017 (UTC)

Rachel Stack GEOG 3900 stack.73 — Preceding unsigned comment added by Rachel.stack4 (talkcontribs) 18:52, 2 March 2017 (UTC)

Evaluation

Overall, the information in this article seems well sourced and relevant: whether explicitly listed within the sentence, or with a hyperlink to the section of the Works Cited where the source is. Although this is a natural occurrence in Wikipedia articles, there is a noticeable dwindling in the strength of the subsections. Especially in regards to the pollen grains, fossil leaves, and lake and ocean sediments sections. Are there any recent/relevant studies that can be cited that give examples of how pollen grain samples led to important discoveries or observations of past climates? Or any images/graphs that could be used for these sections? Although the placement of the ice core image is mildly confusing lay out wise, I think use of more images could greatly benefit this article as a whole.

(GEOG3900)

- Abigailwerner (talk) 20:20, 2 March 2017 (UTC)

I think the section where it discusses water isotopes and temperature reconstruction should appeal to a more general audience; the language is complicated and many of the terms that are used are not common knowledge to the average person, such as "isotopes" or "glacial-interglacial", as well as the formulas and chemical information that are given. Maybe these terms and formulas should be explained a little more so the average reader can understand. The "fossil leaves" section could also probably be improved upon; it's very short and it is unclear exactly what fossil leaves are as it does not explicitly state it anywhere.

Also, many of the sources listed at the bottom of the page seem to be slightly outdated, as many of them are from the early 2000's. Information in science, especially climate science, seems to add up exponentially over time (at least from my experience), and the historical data that we have now in 2017 may be drastically different than the data from the early 2000's due to technological advancements and a greater interest in topics regarding climate. JSteponick11 (talk) 22:54, 2 March 2017 (UTC)

Critique

The first paragraph in the 'Proxy' subsection under 'Ice Cores' may need clarification. The final sentence mentions only northern transport, but it should include southern movement as well. While the source appears valid, a more clear narrative may be useful here. Further, regarding 'Corals', a 2-sentence quote from the conclusion of a paper is found in the middle of the paragraph, which should be paraphrased. A check of the source link directs me to NASA's Earth Observatory Newsroom, which states it is no longer being maintained, and all resources have been moved. Will need to look further into this issue to find the mentioned source.Jmead2 (talk) 16:07, 22 April 2017 (UTC)

Comment

There's also research in using Dynoflagellate Cysts as proxies for productivity, temperature and salinity in different areas like the Pacific North west, Africa, and in glaciers. Perhaps a section on that could be added as well. Some examples of sources: http://www.sciencedirect.com/science/article/pii/S0277379104002112 http://www.sciencedirect.com/science/article/pii/S0034666703001180 65Eq (talk) 19:03, 24 April 2017 (UTC)65Eq

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1. ^ Sean A. Crowe, Lasse N. Døssing, Nicolas J. Beukes, Michael Bau, Stephanus J. Kruger, Robert Frei & Donald E. Canfield (2013). [Abstract New York Times "Atmospheric oxygenation three billion years ago"] Check `|url=` value (help). Nature Letter. Nature. doi:10.1038/nature12426.
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3. ^ Felix Gradstein, Gabi Ogg, James Ogg, and Mark Schmitz (2012). The Geologic Time Scale 2012. A chronostratigraphic Division of the Precambrian. Elsevier. doi:10.1038/nature12426. ISBN 9780444594488.