Talk:Global temperature record

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 19 January 2021 and 7 May 2021. Further details are available on the course page. Student editor(s): YuyanWang.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 22:27, 16 January 2022 (UTC)

Page creation

(William M. Connolley 22:43, 1 Mar 2005 (UTC)) I created this page, following discussion Talk:Temperature_record_of_the_past_1000_years#No_one_has_objected, as a link page for the various temperature records pages from various sources.

No Temperatures on this page (despite the title)

There are no temperatures in the article. The title needs to be changed to reflect the content (maybe 'temperature anomaly record'). If actual temperatures (in degrees Celsius, Fahrenheit or Kelvin) are available, maybe a new page with the original title could be created.

---

Years later I come here looking for the same thing. Finally found an explanatory NASA page https://data.giss.nasa.gov/gistemp/faq/abs_temp.html giving the Surface Air Temperature (SAT) global average as around 14 C. That's 287 K without a suppressed zero. So a 1 degree Celsius anomaly is about 0.3 percent. Rairden (talk) 19:07, 23 July 2019 (UTC)

Or it's about 15% of the range of a typical medical thermometer. On the other hand, a 0.3% percent in average ocean depth is more than 10m. Even relative measurements are relative.... --Stephan Schulz (talk) 20:18, 23 July 2019 (UTC)

Geologic Temperature Record

I created a page on the geologic temperature record in order to provide a place for a deep time perspective for changes in Earth's climate. Right now it is pretty qualitative and not well-documented, but at least it is a start. Dragons flight 07:24, Mar 3, 2005 (UTC)

Paleoclimatology ? — SEWilco 08:25, 3 Mar 2005 (UTC)

Followup moved to Talk:Geologic temperature record

Several points. The paleoclimatic record of the last 540 million years, which covers the time during which multicellular organisms have been abundant and most of the time (600 My) during which there has been enough oxygen in the atmosphere to sustain animals. During that time, we are currently at the near absolute minimum observed CO2 levels, perhaps even dangerously so. When you do not examine the record of relevant to life temperatures, insolation, water vapor, CO2, and oxygen and it its place misrepresent short term trends by including regression lines for transient phenomena, the predictive value is very low, the correlations are false, and the conclusions erroneous. 216.197.221.91 (talk) 11:41, 17 May 2023 (UTC)

Temperature records

Since the title of this article is "Temperature Record", it should be limited to the discussion of, well, temperature records and not speculations about past temperatures (when there were no records) based upon inferences drawn from secondary or tertiary sources.--JonGwynne 04:37, 27 Apr 2005 (UTC)

The information and the comparisons are valuable. Rather than taking a hatchet to it, how about discussing ways to improve the description if it bothers you to refer to these as "records"? Personally, I don't really consider it a problem since I doubt anyone would be confused into thinking that they had well-calibrated thermometers thousands (let alone millions) of years ago. Dragons flight 05:14, Apr 27, 2005 (UTC)

There are plenty of places elsewhere that discuss these data and plenty of links to those places. My point here is simply that when in an article called "Temperature record", we should stick to the subject of the article. See what I mean? If I wrote an article entitled "Major League Baseball" and started talking about hockey, that wouldn't be appropriate, right? In reality, this article should probably be deleted as it serves no useful purpose and doesn't contain any information that can't be found elsewhere.--JonGwynne 05:55, 27 Apr 2005 (UTC)

I found it useful. And maybe the information is elsewhere but this was my fourth Google hit - and the other three really were useless. So please don't remove it because it may help others like me who don't know much about the subject.

It was created to provide a unifying look at temperature changes across all interesting time scales, and I believe that is a useful purpose. Dragons flight 06:00, Apr 27, 2005 (UTC)

You might be right, but it can't possibly serve that purpose since there is no way to know what temperatures were before records were made. Something shouldn't be called a "record" when it isn't. --JonGwynne 06:49, 27 Apr 2005 (UTC)

Obviously, many scientists believed there are ways to reconstruct temperature changes based on a variety of proxies. If you would prefer to call those "reconstructions" or something similar rather than "records", I might be willing to go along with that, but you seem to be arguing that there is no evidence (i.e. no record) of past temperature changes, and that simply isn't true. If you want to argue over semantics, please suggest an acceptable alternative. Dragons flight 06:59, Apr 27, 2005 (UTC)

This is the problem, I don't think there is a single term that can encapsulate both actual records and inferences drawn from proxies - and some of the proxy choices are pretty dodgy... I mean, the idea of trying to extrapolate climate changes from tree rings?! Give me a break. But I digress... There are already articles in wiki that talk about the climate changes (documented and theorized) over various time spans, I don't see why this wholly redundant one is needed.--JonGwynne 07:10, 27 Apr 2005 (UTC)

Personally, I'm quite happy to think of the one as "direct" temperature records and the other as "indirect" temperature records, and just call the whole thing "temperature records". In my opinion, someone reading about ice cores, sediments, and tree rings is unlikely to mistake the ancient records for direct thermometry. Since you don't seem to have a constructive suggestion in that regard, I don't see as how there is anything to be done about it. As far as whether the page has a right to exist, I think it does, and I am fairly sure that a variety of other people do too, but I can't stop you from listing it on VFD if you want to challenge that. Dragons flight 21:37, Apr 27, 2005 (UTC)

(William M. Connolley 09:19, 27 Apr 2005 (UTC)) JGs distinctions are specious. All T "records" are proxies, but some (thermometers) are more exact than others (d-o-18).

Do please explain how a direct record of temperature collected by the measurement of temperature by a thermometer is a "proxy". I'm most interested to hear your explanation.--JonGwynne 16:50, 27 Apr 2005 (UTC)

Yes, a thermometer is a proxy. Suppose you have a thermometer in a cornfield in Iowa in 1850, in 2023 there are 100000 people living there, all heating their homes in the winter, and using their air conditioners in summer. Suppose the cornfield is now 10 miles away. The thermometer hasn't changed position, but the cornfield has, and now reads 1 degree hotter than it did. The old adage is, "you can never return to the same place." I suppose you could argue that the thermometer isn't the proxy, but its location is, and that, is an irrelevant distinction because the question is whether the climate has changed, not the thermometer reading. Generalizing from temporally limited data about climate that should be measured every 10 million years or so is not at all convincing. There was a particularity bad paper that looked at 10 or 20 years of data and concluded that the climate is not changing. What makes you think that looking at 100 years of data is any better? You might try training yourself on the stock market, when you lose your shirt investing in something that seems to be a good idea because of a trend, come back here reread that you have to look at the fundamentals before you invest, not on what you think a local trend predicts. 216.197.221.91 (talk) 08:20, 18 May 2023 (UTC)

What is temperature JG? How does a thermometer work, (liquid based and bi-metallic)? Think about those two questions and figure it out :-) Vsmith 17:23, 27 Apr 2005 (UTC)

If you can't provide an answer, there is no reason to be rude.--JonGwynne 06:38, 28 Apr 2005 (UTC)

I keep all my temperature records in the form of air samples in perfectly insulating containers. I found that sealed jars in the freezer stored the gas samples OK, but the temperature records were unreliable for some reason. (SEWilco 03:01, 28 Apr 2005 (UTC))

Does JG say that carbon dating is not a record of how old something is because one uses a proxy to calculate it? Science is the art of inferring from primary sources using artifical measures as proxies to represent a quality in a quantitative way (e.g temperature). JG's approach would mean there was no science. He needs to read more.

Temperature records?

Is there a article about high and low temperature records? the highest and the lowest? or Avg hi and avg Lo? Not just the data of the record itself ... J. D. Redding 04:48, 30 April 2007 (UTC)

nvr mind ... found something that will work. Temperature extremes ... might to a top disambig on this page to note extreme records vs record as a set of data ... J. D. Redding

Loehle paper

The US National Academy of Sciences looked into the Hockey Stick controversy and advised that strip bark trees are not temperature proxies. Since all trees more than 600 years old are strip bark trees, Loehle reconstructed temperature going back 2,000 without using tree ring data. He found the MWP to be consistent at the 18 sites he studied all over the globe and found the MWP was 0.3C warmer than the late 200th century. [1] RonCram (talk) 01:37, 18 November 2007 (UTC)

And E&E is still not a WP:RS --Kim D. Petersen (talk) 02:08, 18 November 2007 (UTC)

E&E is a peer-reviewed paper. It is ridiculous to claim it is not RS. Loehle's reconstruction is beginning to get media attention.[2]RonCram (talk) 15:19, 21 November 2007 (UTC)

Where is your evidence that E&E is PR? William M. Connolley (talk) 15:34, 21 November 2007 (UTC)

I'll argue the paper is RS. If you check the website you will see the Editorial Advisory Board of over 50 names and organizations. The research submitted here goes under much scrutiny, and all sources are checked before publication. If you read the instructions to the authors you will get an idea of what has to be done to publish with this paper. Also if you check the paper again there has been an add on in January of 2008 suggesting new evidence. These findings should be doubly checked and posted on wiki as an alternative to other research findings. Infonation101 (talk) 06:06, 19 February 2008 (UTC)

Jancovici, Jean-Marc. How do the present temperatures compare to the past ones? Jean-Marc Jancovici, 2004. "It is remarkable that over the last 400.000 years, the maximum of the yearly average of the temperature exceeded the present values by just 1 to 2 °C (average temperature on earth was then 16 to 17 °C compared to 15 °C today) ; the last time that we reached such values was 130.000 years ago." 16–17 °C

(1600 AD)James Hawley:Jean-Marc Jancovici

15 °C (November 2004) —Preceding unsigned comment added by 76.1.94.141 (talk) 20:33, 9 August 2010 (UTC)

Update Graphs?

Would it be possible to update the temperature record graphs to reflect more up-to-date information? I keep reading that global temperatures haven't risen in quite some time, and it would be nice if this page noted that. Zoomwsu (talk) 00:26, 6 June 2008 (UTC)

I don't know what the temperatures have done, but I came to note that the chart used is 4 years out of date and needs updating Stephen W. Houghton II 70.150.94.194 (talk) 15:01, 10 October 2008 (UTC)

To translate Datei:Erdgeschichte.jpg in the German WP would be excellent, it covers the whole 3,6 Billion years basic climate record. BR --Polentario (talk) 00:55, 23 January 2009 (UTC)

That picture de:Datei:Erdgeschichte.jpg, might be more suitable for Paleoclimatology. I don't think it really needs to be translated: how many different possible meanings can words like "Praekambrium", "Warmklima ohne Eis", and "Eiszeitalter" have? Having said that, that graph lacks a temperature scale. --TS 01:23, 23 January 2009 (UTC)

On the substantive question, for up to date temperature records it's probably better to consult the primary sources than to rely on an encyclopedia, which tends not to be concerned with the very recent past. --TS 01:36, 23 January 2009 (UTC)

Graph

The graph on the upper right is bassed on reseasrch that has been shown to have significant flaws http://www.climateaudit.org/pdf/others/07142006_Wegman_Report.pdf

It leaves the impression that the the Medival Warming Period was coldder than today. There is not a scientific consensus to support this notion. —Preceding unsigned comment added by Markllo (talk • contribs) 01:11, 17 February 2009 (UTC)

The graph on the upper right shows the instrumental temperature record and starts in 1880. The Medieval Warm Period (if it existed as a global phenomenon) was around 800 years earlier. The File:2000 Year Temperature Comparison.png figure, on the other hand, shows 10 different reconstructions, only one of which has been the subject of Wegeman's criticism - and that criticism is by no means accepted unanimously. --Stephan Schulz (talk) 21:44, 22 February 2009 (UTC)

As I understand it, most of the other reconstructions share one or more of the same flaws for which the original hockey stick was criticized by Wegman and others. For instance, if the scientific consensus as reflected in the NAS/NRC studies includes that the MBH reconstruction was flawed by the inclusion of strip-bark samples (eg, the bristlecone pines), you can't appeal to other studies that get their shape from the exact same strip-bark samples as evidence the flaw "didn't matter". --Blogjack (talk) 06:09, 8 March 2009 (UTC)

The graph now shown is from the PAGES2K data set. Is there any substantive criticism of it, or any other alternative? Skierpage (talk) 20:03, 3 March 2023 (UTC)

Y2K Bug Causes Skewed Data?

I stumbled upon a video describing an apparent bug in NASA's temperature record. The original blog post with the findings can be found here: [3]

I wanted to verify the claim so I checked out a climate change advocates response: [4]

In addition: NASA apparently fixed the data with the following record: [5]

I tried finding an official NASA response, but couldn't find it. Can someone compile this issue into the wikipedia article? —Preceding unsigned comment added by 67.181.240.170 (talk) 04:05, 17 October 2009 (UTC)

Why does none of this data show temperature? They all show some "anomaly" measure. Given that this is an open project it seems prudent to have unanalysed data recording the actual temperature (or year mean for some location, or mean of means even) and not some secondary statistic. —Preceding unsigned comment added by MiniPsybetron (talk • contribs) 21:40, 10 May 2010 (UTC)

Pending changes

This article is one of a small number (about 100) selected for the first week of the trial of the Wikipedia:Pending Changes system on the English language Wikipedia. All the articles listed at Wikipedia:Pending changes/Queue are being considered for level 1 pending changes protection.

The following request appears on that page:

However with only a few hours to go, comments have only been made on two of the pages.

Please update the Queue page as appropriate.

Note that I am not involved in this project any more than any other editor, just posting these notes since it is quite a big change, potentially.

Regards, Rich Farmbrough, 20:36, 15 June 2010 (UTC).

This article has been excluded from the pending changes trial because there is lack of disruptive activity here that would justify applying any type of page protection here. 山本一郎 (会話) 02:49, 23 June 2010 (UTC)

1980 or 1990

The source for the graph http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.txt Says "(Anomaly with Base: 1951-1980)". The info on the image pages says 1961-1990.

Also, how come it gives 2005 as hottest when pretty much everywhere else (including other graphs on this page) give 1998? —Preceding unsigned comment added by 92.2.6.248 (talk) 14:52, 13 August 2010 (UTC)

Was it warmer then today?

This page says not:

http://en.wikipedia.org/wiki/Holocene_Climatic_Optimum

While temperatures in the Northern Hemisphere were warmer than average during the summers, the tropics and areas of the Southern Hemisphere were colder than average which comprised an average global temperature still overall lower than present day temperatures.[4]

And in our article on Temperature record it says otherwise: The Holocene Climatic Optimum was generally warmer than the 20th century,

Isn't that inconsistent? — Preceding unsigned comment added by 62.87.247.31 (talk) 22:21, 17 June 2011 (UTC)

Global Average Surface Temperature

Global Average Surface Temperature redirects to here. This seems incorrect, given the fact that nowhere on this page is there a measurement of the global average surface temperature, past or present. There is ample discussion of changes in that measure over time, but no actual discussion of that measure itself. It seems to me to be a failing, if this article doesn't at least represent the title of the article and of all articles that redirect here. Whether Global Average Surface Temperature should cease to redirect here, and potentially be it's own page (assuming someone populated it with information), or whether the information should be included on this page is to me fairly arbitrary, thoughts?

I personally think this article is itself mis-titled. It isn't about the temperature record, it's about historical temperature trends. It has trends, but no baseline. I don't think anyone could determine what the recorded temperature was at any time or place by use of this article, without external research, which defeats the purpose of this entry. This entry seems less encyclopedic and more appendical to the theoretical article that belongs under this name. AaronMP84 (talk) 06:15, 14 August 2012 (UTC)

Christiansen & Ljungqvist 2012, new NH temp reconstruction for past 2000 years

"The extra-tropical Northern Hemisphere temperature in the last two millennia: reconstructions of low-frequency variability" by B. Christiansen and F. C. Ljungqvist, Clim. Past, 8, 765-786, 2012

http://www.clim-past.net/8/765/2012/cp-8-765-2012.html (with link to full text) doi:10.5194/cp-8-765-2012

• "This work is distributed under the Creative Commons Attribution 3.0 License."

This interesting new reconstruction has a number of findings that challenge the current IPCC consensus:

• Our reconstructions indicate – in agreement with the results of Moberg et al. (2005); Ljungqvist (2010), and Loehle and McCulloch (2008) – that the first millennium AD was generally significantly warmer than the second millennium AD. The 17th century was the coldest century during the last two millennia and most of the LIA seems to have been colder than during the Dark Age Cold Period ca. 300–800 AD. [end quote]

The meat of the study is in Figures 5 & 6 (p.11 of PDF). Published 4-18-12. Early days, but should be considered for our article. --Pete Tillman (talk) 22:18, 17 October 2012 (UTC). Professional geologist, advanced-amateur paleoclimatologist.

Do please explain what "findings that challenge the current IPCC consensus" - since none of what you are quoting is outside of what our article currently writes - nor afaik in any way contradictory to anything in the AR4. Be specific - you can quote the relevant sections from the AR4 while you do it. --Kim D. Petersen (talk) 02:11, 18 October 2012 (UTC)

---

Another recent paper supporting a warmer MWP is Esper et al. 2012, "Variability and extremes of northern Scandinavian summer temperatures over the past two millennia," Global and Planetary Change 88–89 (2012) 1–9 Link to full text: [6] From the abstract: "The record provides evidence for substantial warmth during Roman and Medieval times, larger in extent and longer in duration than 20th century warmth."

Of course, this is for a relatively small area compared to Christiansen & Ljungqvist 2012, but it adds some interesting regional details.

Kim, I'll address your query on another occasion -- busy time for me. --Pete Tillman (talk) 18:09, 18 October 2012 (UTC)

New image with extensive text that is mostly free of RS citations

In this edit we have replaced an old image with the one in the thumbnail. At the file page there is an extensive summary section with a lot of text that appears to lack RSs.

Thoughts? How does one tag images about sourcing? NewsAndEventsGuy (talk) 13:28, 29 April 2014 (UTC)

If you click the image, the related cites are there, thus i cannot understand why you cite the lack of RS. However, the image text should be improved to include the explanation about ocean, land surface, and sat obs data. Though, it is unclear why the image does not show the lowest RCP. And maybe the discussion should be on the image talk page. Ofc, it would be nice to have the image "confirmed" by a reliable 3rd party, but so far the image appears to be ok. prokaryotes (talk) 18:36, 29 April 2014 (UTC)

The image should actually show RCP6 and RCP8.5, not RCP4.5 and RCP8.5. RCP6 and 8.5 are intended to span likely outcomes with little or no emission reduction, which is effectively the status to date, and therefore relevant to the temperature history to date as plotted. OTOH RCP4.5 and RCP2.6 are designed to represent moderate and severe future emission reductions, which are not directly relevant to observed temperatures to date. Read (and please expand) representative concentration pathways, and the references therein (and fix the capitalisation...). --Gergyl (talk) 12:19, 1 May 2014 (UTC)

There may be links purporting to be data sources (I have not verified them) but there is a gread deal of text that lacks any RS whatsoever...... I'm at a loss why you "cannot understand" that text requires support via citations. NewsAndEventsGuy (talk) 19:01, 29 April 2014 (UTC)

Maybe verify the data sources then, before you make vague suggestions? prokaryotes (talk) 20:07, 29 April 2014 (UTC)

What's vague about Wikipedia:Verifiability and the image's extensive "summary" text lacking citations? We don't tolerate citation-free articles. Same difference. Nothing "vague" about the NPOV WP:PILLAR which requires sources for verification. NewsAndEventsGuy (talk) 20:21, 29 April 2014 (UTC)

There is no reason to assume that the data on the temperature records is a issue. The problem is, that we cannot verify that the author of the image made no mistakes when plotting. It would be nice if the author could clarify the points made (and maybe submit a source which verifies the image). prokaryotes (talk) 10:01, 30 April 2014 (UTC)

I haven't complained - ever - about the data sources or the plotting, so I must be talking about something else (i.e., text created by the image author must have RSs). Notice that I'm not advocating for image removal anymore. But if RSs can not be supplied to the image text written by the image creator, then I'll likely go for image deletion instead of just removing it from this article. NewsAndEventsGuy (talk) 10:07, 30 April 2014 (UTC)

Ok, fine, but give the author time to respond here. prokaryotes (talk) 10:29, 30 April 2014 (UTC)

Err, maybe chill guys; way OTT IMO. Umm, who "verified" the Rob Rohde image it replaced? That image is way out of date and shows just one temperature series, and not necessarily a currently preferred choice. (That would be maybe Cowtan & Way, or even Rohde's own work at Berkeley Earth, published last month -- which I do plot!) So, let's see, if the extensive explanatory text was just replaced with a nebulous list of sources (like a trillion other WP graphics), that would be fine? Odd. The text will be improved in time. Unless you missed it, that's actually the idea here. Rather than whinge, why not help? --Gergyl (talk) 12:19, 1 May 2014 (UTC)

First time I ever heard anyone say the core policy of verifiability is "over the top". If you copy-paste text from your own blogs under a CC 3.0 license, that's great. However, the text still needs to be based on RSs. Since its your text, you must have those available because - I trust - you're not just uploading WP:Original research. Since you have the RSs, please plug them in, because verifiability is a core policy here. NewsAndEventsGuy (talk) 12:53, 1 May 2014 (UTC)

With respect friend, your apparent concern that the graph lacks verifability is incorrect. The description page includes links to bona fide data sources for every single data point on the graph. Those include NASA GISTEMP, HadCRUT4, Cowtan & Way, NOAA NCDC, Berkeley Earth, NCEP NCAR, RSS and TLT. The description page also includes a link to the open-source spreadsheet that plotted the data. If one wanted to verify, one could consult the data links provided and the open source plotting. Alternatively, someone genuinely concerned about the accuracy of the plot could just overlay the old one on top of it graphically (they use very slightly different reference intervals, about 0.1°C apart). Like this:

I've agreed elsewhere that the descriptive text at the image page needs attention. The appropriate place to discuss that would be there. --Gergyl (talk) 08:17, 3 May 2014 (UTC)

In numerous remarks I have talked about the lack of RSs in the summary text on the image file page, but I don't think I have said anything about the plot or data sources. NewsAndEventsGuy (talk) 09:47, 3 May 2014 (UTC)

Which problem has since been addressed, no? As I said it would be in time. I don't spend every hour of every day working on this thing. Some patience would have been appreciated. --Gergyl (talk) 10:51, 3 May 2014 (UTC)

Other than appropriately marking it as needing references, and changing my mind about its use through appropriate BRD discussion, in what way was I not patient? NewsAndEventsGuy (talk) 12:07, 3 May 2014 (UTC)

NewsAndEventsGuy, since you mentioned to keep the image (unless it would be deleted), the newer version from Gergyl appears better, but i agree some sort of second verification would be nice, such as a mention or inclusion from another expert. Basically we should use the newer version and more extensive one. prokaryotes (talk) 14:40, 1 May 2014 (UTC)

New lede image

Rohde's old GISTEMP plot shows just one estimate of the recent global temperature record, when there are now at least five. It also shows only annual values when all five series provide monthly data. Plotting annually loses important context above the variability inherent in the temperature record (for example, the 1998 El Niño spike). Some other series provide more coverage (start earlier) and use more modern (arguably better) interpretation methods (Berkeley Earth, Cowtan & Way). I propose to replace Rohde's plot with a version of File:Global_monthly_temperature_record.png showing the five recognised instrumental series (including GISTEMP) without the reanalysis and satellite series (which are not relevant in this context). An svg version is in preparation.--Gergyl (talk) 11:17, 3 May 2014 (UTC)

Proposed move

I would propose moving and renaming this article as Global temperature record. The current title Temperature record is ambiguous; it could refer either of the subtopics Geologic temperature record or Instrumental temperature record; it could also be mistaken for List of weather records, by readers searching for records of extreme temperatures.

The title should be WP:PRECISE and unambiguous enough to fully define the scope of the article. In this case, the topic is not the record of any arbitrary set of temperatures, but the record of global average temperatures (in atmosphere and oceans) over as much time as such temperatures can be measured or inferred. —Sangdeboeuf (talk) 09:24, 12 December 2017 (UTC)

Y Since no objections have yet been raised, I've moved the page. —Sangdeboeuf (talk) 01:22, 16 December 2017 (UTC)

I think this was a good move, Sangdeboeuf. I had made a similar suggestion for instrumental temperature record. I felt the word "global" should also be added there. My proposal is shown here but was rejected. Perhaps we can ponder together if the title instrumental temperature record needs to be changed? EMsmile (talk) 08:26, 20 May 2022 (UTC)

Measuring global temperature record

It would be nice if there would have been more information in this article regarding thermometers since there is one line and then a reference to another article. As well, it could be improved if the article had a simpler layout with less large paragraphs and run on sentenceSchneidl12 (talk) 18:57, 31 January 2019 (UTC)

Semi-protected edit request on 17 August 2021

Can this be renamed the "Global temperature anomaly record" ? Since no one has taken the time to put in the base values since it was first written and requested, the revised name would tell people this page has no temperature readings at all, just deviations from some arbitrary baseline values which are different based on the data set chosen. 2600:6C67:867F:DC44:C0B3:4AC0:D225:B6D7 (talk) 22:55, 17 August 2021 (UTC)

 Not done: page move requests should be made at Wikipedia:Requested moves. —Sirdog9002 (talk) 23:00, 17 August 2021 (UTC)

I've made some changes to set it apart from instrumental temperature record

I came to this article today because User:ASRASR had pointed out the following to me: "But what about the existing article (Global temperature record) - Can't this and the instrumental temperature record be merged? Uses the same graph in the lead." I think a merge might not be needed but the scope of the article had to be clarified. To start with, having the same images in the lead is not good so I have changed that now. Also, I felt that the article would be better off going from the oldest to the most recent time period. So I have changed the ordering. Also, I have used the excerpt function for the section on "instrumental temperature record". I hope this will make it easier for readers to find their way around. I think that most people searching for global temperature stuff really want to know that part that our GHG emissions are causing. So most likely what they actually want to know is the content that is here: instrumental temperature record. For that reason, I have also added a hatnote. I have also started to build up the lead but more is needed. EMsmile (talk) 08:30, 20 May 2022 (UTC)

Ice core temperatures end at 1950!

The "Ice cores (from 800,000 years before present)" section should mention that ice cores define "the present" as 1950, i.e. they end before the ~0.9°C of warming in the instrumented temperature record since then. The chart File:EPICA_temperature_plot.svg

doesn't say this, you have to visit the Wikipedia page for its data European Project for Ice Coring in Antarctica to see the mention "age (years before 1950)". I've requested the change on its talk page and for now put "1950" in the image's caption.

The definition of 1950 as "today"/"the present"/the time for "ago" seems common in paleoclimatology, e.g. https://www.ncei.noaa.gov/access/paleo-search/cvterms?termId=133 says

calendar year before present

an age unit of years, calibrated to actual years if derived from radiocarbon dating, before present with present defined as 1950 Common Era. Times after 1950 CE are expressed as negative values.

Somewhere I read a reference explaining that snow takes time to compact to form ice cores, so they're not a good proxy for temperatures in recent decades, but alas I can't find it.

If this applies to every section of the article, it should be mentioned in the introduction, otherwise each mentiom of "present" and "ago" needs the clarification. A lot has happened since 1950. -- Skierpage (talk) 20:29, 3 March 2023 (UTC)

Please define "temperature anomaly"

All of the graphs plot the "temperature anomaly" but this term does not seem to be defined anywhere. I gather that it is the temperature with respect to some reference time period, but this should be explicitely explained (and perhaps linked to from the graphs, since they appear on multiple pages).

—Steven G. Johnson 18:07, 26 September 2006 (UTC)

What is a temperature anomaly? The Y-axis on these graphs shows increases and decreases in average temperature “anomalies.” An anomaly is a deviation, or variation, from a “normal” temperature.

Jennifer Z —Preceding unsigned comment added by 69.153.86.42 (talk) 19:50, 10 October 2009 (UTC)

Define "normal". Define "0 degree" on the graphs. Otherwise the graphs mean absolutely nothing, as nothing tells deviation or variation compared to what is on presented.

Temperature anomaly is relative to the Earth's pre-industrial average temperature, which was remarkably stable for several thousand years. This article explains it for the 2015 Paris Agreement, from that: "The treaty did not define a particular preindustrial period, though scientists generally consider the years from 1850 to 1900 to be a reliable reference; this time predates humans’ use of fossil fuels and is also the earliest period when global observations of land and sea temperatures are available. During this period, the average global temperature, while swinging up and down in certain years, generally hovered around 13.5 degrees Celsius, or 56.3 degrees Fahrenheit." Similarly, a 2016 FAQ from the IPCC says "This IPCC Special Report on Global Warming of 1.5°C uses the reference period 1850–1900 to represent pre-industrial temperature. This is the earliest period with near-global observations and is the reference period used as an approximation of pre-industrial temperatures in the IPCC Fifth Assessment Report." This should probably be added to the article. I haven't found the IPCC definition of the temperature, this is a relevant paper -- Skierpage (talk) 01:38, 6 October 2023 (UTC)

Hi User:Skierpage, it wasn't clear to me which changes you want to make. Maybe just go ahead with them, although do keep in mind that when it comes to IPCC info this is probably more relevant for this article: Instrumental temperature record. It's important not to create more overlapping content than necessary. EMsmile (talk) 07:45, 26 October 2023 (UTC)

@EMsmile Yes, I'm not sure where to put the information in what article. But the instrumental temperature record covers specific years in the Common Era calendar; it doesn't have the problem of a missing technical definition of what "ago"/"the present" mean and the 73 year mismatch of 1950 with people's understanding of "the present" as "this year." In this article it feels like it's a preface (prefatory?) remark. -- Skierpage (talk) 07:59, 26 October 2023 (UTC)

Hi Skierpage, we don't normally do "preface" remarks but we could add a section on terminology or definitions perhaps? This could be useful. EMsmile (talk) 08:54, 13 November 2023 (UTC)

Need elaboration or citation for following wordings

"Gradual changes in Earth's climate of this kind have been frequent during the Earth's 4,540 million year existence and most often are attributed to changes in the configuration of continents and ocean sea ways." I'm at a loss tp know the meaning of "and most often are attributed to changes in the configuration of continents and ocean sea ways.", can anybody help? Thanks. ThomasYehYeh (talk) 00:27, 20 February 2024 (UTC)

I think the descriptions relates to continental drift over long periods of times. —RCraig09 (talk) 10:48, 20 February 2024 (UTC)

I've attempted to improve the wording now. Hope I got it right. Pinging also User:Dragons flight who wrote that section in the first place. EMsmile (talk) 10:32, 5 March 2024 (UTC)

Can anybody help rephrase the caption for [[File:EPICA temperature plot.svg]]?

"Temperature estimates relative to 1950 from over 800,000 years of the EPICA ice cores in Antarctica. The present (1950) is on the right side of the graph." The current wordings are difficult for me to understand. Thank you. ThomasYehYeh (talk) 00:33, 20 February 2024 (UTC)

Rewording of caption  Done —RCraig09 (talk) 10:47, 20 February 2024 (UTC)