Talk:Instrumental temperature record

message: Comment by Blair Trewin: "I think either as an addition to this section, or a new section (I prefer the latter), there should be a discussion of how global temperature datasets are developed from the base observations, and a listing of the main datasets. Reanalyses, and how they are used/not used, could also be introduced here - I see there is a Wikipedia article for 'Atmospheric Reanalysis', although it could do with some more content. (I'm not a reanalysis expert but can point you to some if you want that article strengthened)." EMsmile (talk) 14:29, 17 March 2022 (UTC)
thread_title: How global temperature datasets are developed from the base observations

message: I am continuing the article review with content expert Blair Trewin. He sent me the following: "I think there's two significant points to make a decision on:
* Now that the IPCC temperature data set is available in a publicly accessible archive, I suggest that we should use that where appropriate, e.g. in the two tables that currently use NOAA data. If you agree I can provide the numbers.
* I think the section that's currently about satellite temperature data should instead be reframed as upper atmospheric temperature, referring to the main sources of information – satellite (with link to the article on that), reanalyses and radiosondes. This would largely draw on the material in IPCC AR6 section 2.3.1.2. If you agree I can draft some text on this.
Main other things outstanding from my perspective:
* Drafting some further text for the lead, and a few other bits where flagged
* Adding a wider range of citations more generally"
Comments/objections on these suggestions changes by anyone? If not, we'll go ahead. EMsmile (talk) 10:27, 22 March 2022 (UTC)
replies: text: Comment from Blair: " I see from the talk page that there were no objections to our proposed restructurings/additions, so can go ahead with those. (The upper atmosphere part also addresses what you mentioned in the talk page under the heading 'removed content about global temperatures')." EMsmile (talk) 08:45, 30 March 2022 (UTC)
thread_title: Continued review with content expert

message: ===About the graph in the section on warmest years: "Global area reaching record temperatures"===
Comment by Blair about this graph: "This figure is about records at the regional level, not in global means - I would move it to the regional temperatures section and introduce a discussion on extremes there." Answer by  above was: "I think that the graphic is appropriate where it is, since it tallies temperature records worldwide. The already-crowded Regional temperature section is actually less appropriate since the graphic isn't concerned with regions per se." Answer by Blair: "It's a global aggregation of regional results (i.e. it is the percentage of gridpoints which set a record in each year). It doesn't relate directly to the global average temperature which is what is being discussed at this point." Do we follow Blair's argument?  EMsmile (talk) 15:18, 24 March 2022 (UTC)
replies: text: The thrust of this graphic is global area. Granted, that's not exactly the same as global average, but it's much more relevant to the global viewpoint than to the distinctions between regions that is the subject of the tiny "Regional temperature changes" section. It's OK to maintain the current mix of global area and the global average temperatures "that is being discussed at this point." —RCraig09 (talk) 16:39, 24 March 2022 (UTC)
replies: text:  Answer from Blair: "on the first graph - if it's going to stay where it is, it probably just needs a bit of text to better link the graph to the text and explain what it's telling us - I can do this. EMsmile (talk) 08:44, 30 March 2022 (UTC)

text: In making this graphic, I followed the data categories in the original source. I didn't group "strong" with "very strong"—they're distinct colors for distinct categories. —RCraig09 (talk) 16:45, 24 March 2022 (UTC)
replies: text:  Answer from Blair: "on the second one - I see what's happening now - there's no 'Very strong' label for La Nina since no year has yet reached the 'Very strong' criteria for La Nina (whereas some have for El Nino). I still think it might be better to add 'Very strong' to the La Nina legend for balance even though it isn't used (yet), but don't feel strongly about this." EMsmile (talk) 08:44, 30 March 2022 (UTC)
replies: text:  Hi RCraig09, I am just wondering where we stand with this now? See my comments here and just above from 30 March. EMsmile (talk) 10:19, 4 May 2022 (UTC)
replies: text:  Absent specific substantive reasons, I will not change the graphic away from what is disclosed in the reference. In particular, I do not plan to add a 'Very strong La Nina'—"for balance", as suggested—as that would wrongly suggest such years exist. —RCraig09 (talk) 15:37, 4 May 2022 (UTC)
thread_title: Questions about some of the graphs

message: Comment by Blair about this graph: "This figure is about records at the regional level, not in global means - I would move it to the regional temperatures section and introduce a discussion on extremes there." Answer by  above was: "I think that the graphic is appropriate where it is, since it tallies temperature records worldwide. The already-crowded Regional temperature section is actually less appropriate since the graphic isn't concerned with regions per se." Answer by Blair: "It's a global aggregation of regional results (i.e. it is the percentage of gridpoints which set a record in each year). It doesn't relate directly to the global average temperature which is what is being discussed at this point." Do we follow Blair's argument?  EMsmile (talk) 15:18, 24 March 2022 (UTC)
replies: text: The thrust of this graphic is global area. Granted, that's not exactly the same as global average, but it's much more relevant to the global viewpoint than to the distinctions between regions that is the subject of the tiny "Regional temperature changes" section. It's OK to maintain the current mix of global area and the global average temperatures "that is being discussed at this point." —RCraig09 (talk) 16:39, 24 March 2022 (UTC)
replies: text:  Answer from Blair: "on the first graph - if it's going to stay where it is, it probably just needs a bit of text to better link the graph to the text and explain what it's telling us - I can do this. EMsmile (talk) 08:44, 30 March 2022 (UTC)
thread_title: About the graph in the section on warmest years: "Global area reaching record temperatures"

message: Comment by Blair about this graph: "This looks like something that's been produced specifically? (WMO has from time to time published something conceptually similar in its annual State of the Climate reports but hasn't distinguished strong from weak events). If it doesn't have a defined source then we probably need to have a link somewhere to how the strength of El Nino/La Nina events is defined". My reply to him: "The full explanation of the graph is accessible when clicking on the graph: https://commons.wikimedia.org/wiki/File:20210827_Global_surface_temperature_bar_chart_-_bars_color-coded_by_El_Ni%C3%B1o_and_La_Ni%C3%B1a_intensity.svg  But I don’t understand it fully: does it explain the definition of strength for these events?" - His next reply was: "It does, although the text has a "very strong" category, which looks as if it is grouped with "strong" on the graph." EMsmile (talk) 15:30, 24 March 2022 (UTC)
replies: text: In making this graphic, I followed the data categories in the original source. I didn't group "strong" with "very strong"—they're distinct colors for distinct categories. —RCraig09 (talk) 16:45, 24 March 2022 (UTC)
replies: text:  Answer from Blair: "on the second one - I see what's happening now - there's no 'Very strong' label for La Nina since no year has yet reached the 'Very strong' criteria for La Nina (whereas some have for El Nino). I still think it might be better to add 'Very strong' to the La Nina legend for balance even though it isn't used (yet), but don't feel strongly about this." EMsmile (talk) 08:44, 30 March 2022 (UTC)
replies: text:  Hi RCraig09, I am just wondering where we stand with this now? See my comments here and just above from 30 March. EMsmile (talk) 10:19, 4 May 2022 (UTC)
replies: text:  Absent specific substantive reasons, I will not change the graphic away from what is disclosed in the reference. In particular, I do not plan to add a 'Very strong La Nina'—"for balance", as suggested—as that would wrongly suggest such years exist. —RCraig09 (talk) 15:37, 4 May 2022 (UTC)
thread_title: About the graph with the caption "Colored bars show how El Niño years (red, regional warming) and La Niña years etc.

message: Dear all, I'm not a climate expert, but an astronomer with keen interest in this topic. I struggled over the first figure in this article that gives the impression that global temperatures have "only" increased by less than 1 degree so far. This is of course due to the use of the very awkward base period 1950-1980 (see also point 13 of the expert review above). I would strongly suggest to use the same base period as the IPCC (and most other publications that I have seen on this topic), i.e. the "pre-industrial" time with instrumental temperature record, 1850-1900 (see. e.g. Fig. SPM-1 in the IPCC's AR6 report): https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM_final.pdf -- if you agree, I'd be happy to update the figure (or if the creator of that figure is still active, perhaps they can speak up). Regards, Ileo (talk) 10:32, 27 July 2022 (UTC)
replies: text: Thanks, seems like an important point you're making here. I copy here Point 13 from the expert review as I had moved your comment to the bottom of the page: "Either here, or in the 'Temperature anomaly' article, there needs to be a discussion of which baseline periods are in use, the purposes they serve, and why the choice of baseline has no impact on long-term trends." EMsmile (talk) 11:21, 27 July 2022 (UTC)
replies: text:  Preliminarily: there is no "correct" base period for temperature anomalies; they are reference periods. More to the point here, only two of the five datasets go all the way back to 1850, so it's impossible to adjust all five datasets to the IPCC 1850-1900 "pre-industrial" reference period. Oddly, "pre-industrial", literally, is before 1850 anyway, so scientifically the IPCC reference period isn't that distinctly authoritative. A main purpose of this graphic is to convey the high correlation among numerous authoritative instrumental temperature record datasets, a purpose that would be thwarted if there were only two datasets. In any event, it's clear from the chart that the change isn't less than 1°C. —RCraig09 (talk) 19:33, 27 July 2022 (UTC)
replies: text:  OK, fair enough but I think the expert reviewer was right when he said "Either here, or in the 'Temperature anomaly' article, there needs to be a discussion of which baseline periods are in use, the purposes they serve, and why the choice of baseline has no impact on long-term trends." Currently the word baseline appears only once in the entire article. I am not sure what the best reference would be to use to explain a bit about the issue of baselines. The article Temperature anomaly doesn't mention the word "baseline" at all. Pinging Ileo. EMsmile (talk) 07:41, 28 July 2022 (UTC)
replies: text:  Temperature anomaly already recites "A temperature anomaly is measured against a reference value or long-term average.[1][2]" The NOAA reference explains anomalies quite thoroughly. —RCraig09 (talk) 14:55, 28 July 2022 (UTC)

text:  P.S. In August 2022, I made substantial additions to the Temperature anomaly itself. I think more detail isn't warranted here. —RCraig09 (talk) 03:10, 22 September 2022 (UTC)
replies: text:  I've made some small edits to the article and the caption of the lead image to clarify this issue of reference point. I think it's important so that it becomes clearer why the data in the graph starts off with negative values in 1850. EMsmile (talk) 09:04, 23 June 2023 (UTC)

text: that's good but I think we should update the caption accordingly. Currently it says: "(In this chart, the "0" value is what is considered the "pre-industrial" temperature level.)" I don't think we can expect everyone to know what pre-industrial means (I would have guessed it means e.g. average of 1800-1850). Would you agree to change the caption to something like this:  or ? EMsmile (talk) 07:54, 14 July 2023 (UTC)
replies: text:   —RCraig09 (talk) 18:03, 17 July 2023 (UTC)
thread_title: Question about the first figure (correct base period to use?)

message: I've just added a wikilink to the caption of the image in the lead, and added "surface": . However, I noticed that we have two very similar articles, and I wonder which to link to. We have:
* global average surface temperature 
* global average temperature --> this wikilinks to Global temperature record
I wonder if there is potential for merging or for improving the article titles. Pinging also User:InformationToKnowledge. EMsmile (talk) 09:44, 7 May 2024 (UTC)
thread_title:  Wikilink for [[global average temperature]]?