Talk:Retreat of glaciers since 1850/Archive 2
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Explanation of disequalibrium
OK... complete non-expert visiting. MONGO, whom I've chatted with on some other topics, pointed out this page to me; it's indeed grown quite quickly from creation to something very substantial.
I find, however, the explanation of glacial equalibrium and disequalibrium a bit thin and/or confusing. From what I can read, my interest is greatly picqued in when a size reduction in a glacier can reflect an adjustment in equalibrium mass and when it indicates disequalibrium. What are the criteria for distinguishing those things, and what measurements are relevant to determining which it is for a particular glacier? Also, though it doesn't match our current historical period, is there sometimes a disequalibrial growth phase in glacier history to parallel a disequalibrial retreat? Or does disequalibrium only apply to retreat? Generally, I'd just like this sort of theoretical issue fleshed out, probably in its own section. Lulu of the Lotus-Eaters 18:08, 9 February 2006 (UTC)
- More on a related point. The chart "Glacial Mass-Balance" is labeled with a "tipping point" to negative mass balance. What's up with that? What defines the labeled date as a tipping point within the almost monotonic decrease in glacial mass? Lulu of the Lotus-Eaters 18:15, 9 February 2006 (UTC)
- Wow, sounds like a you're being modest as these are excellent points. In it's most simplistic form, disequalibrium equals more loss than gain in terms of snowfall and hence glacial development...(I think), equalibrium would equate to little or no retreat or advance of glaciers and I believe (no quoting) that an advancing period such as what occurred during the "little ice age" of 1650-1850 is probably the opposite of disequalibrium, whatever that is...and I'll have to ask Peltoms to take over on this issue. I completely agree that ths issue needs clarification, especially for those that are unfamiliar with glacial activity...these are excellent points.--MONGO 19:48, 9 February 2006 (UTC)
- As far as the chart...I'm not sure what the "tipping point" identifies and that needs clarification in the graph summary.--MONGO 20:04, 9 February 2006 (UTC)
Well I guess it is good that some debate is stirred. I reworked the terminus and mass balance section. The latter is more accurate though I do not feel its clarity much improved. Since mass balance is very distinct from terminus behavior, why are we going into the methods. I made some changes so you can evaluate but I would suggest removing mass balance discussion beyond the definition and as a driving force behind terminus behavior. Mass balance measurements is not simple nor is explaining it, particularly with the different methods used. As to equilibrium and disequilibrium I will take a stab at it. This is a concept that is mentioned, but until my publications this year not published. Indirectly identifying glaciers likely to disappear is the same thing. I just think that calling it what it is a system out of equilbrium is more scientifically appropriate. You can even identify specific dianostic features exhibited by such glaciers. Disequilibrium indicates a glacier that is not simply retreating, but is in the act of disappearing because it cannot retreat to a new point of equilibrium. The opposite of this is not an advance such as the Little Ice Age. That advance led to a new equilibrium position. In the case of the expansion of a mountain glacier system into and ice sheet, that would be a system in disequilibrium, until it expanded into a whole new realm. Peltoms 01:10, 10 February 2006 (UTC)
As to the tipping point. The negative slope decreases at that point, and this is also when retreat rates began to increase as mass balance was worse.Peltoms 01:10, 10 February 2006 (UTC)
- As far as what is in the summary of the graph indicating tipping point, what is the best wording that I can use to explain this?--MONGO 01:25, 10 February 2006 (UTC)
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- I haven't tried any regression or anything, but visually it sure looks like the curve has a negative inflection everywhere, not just at that one point. Lulu of the Lotus-Eaters 06:22, 10 February 2006 (UTC)
Trying to get it
Let me try again at the equilibrium/disequalibrium thing. I'm assuming that equilibrium means something other than stasis here... as in: there is a tendency for change to be self-limiting in certain cases.
So perhaps there's a period during with a fairly limited climate change (i.e. that doesn't cascade beyond a certain point). Glacier A will shrink to half it's size, but at a slowing rate of reduction, and stabilize at that size, despite the warmer temperature, over a few decades. So equilibrium forces still apply to A. In contrast, Glacier B will shrink at an increasing rate until it disappears. So B is in disequilibrium. Is this the right picture?
If I have it right, in my vague layperson way, how do we know whether a given glacier is more like A or more like B. During a period of observation, both shrink. Perhaps the inflection of the mass change is different: is that sufficient? Does the idea of disequilibrium depend on a particular climatological/glacialogical mathematic model? Is this consensus or speculation? Do we have specific equations? Are there broader factors that can help measure status (ambient temperature at site? precipitation rates? size of containing geological features? etc.) Lulu of the Lotus-Eaters 07:13, 10 February 2006 (UTC)
- Excellent point Lulu, you do not share the mental lethargy of the mythic lotus eaters. I think we can use your example in the article, so note its inclusion. Should we have pictures of two glaciers here one that is adjusting and one that is not or just refer to the pictures of said glaciers in other parts of the article. The data sources should not be at the top, nor are they sources, these are general methods, specific methods for each data source are contained in our links. We are asking the reader to read the most difficult and driest material first. I think they will get lost in the trees before seeing the forest. Peltoms 14:08, 10 February 2006 (UTC)
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- Thanks, Peltoms, for helping explain this. I'm so glad a modified version of my hypothetical seems usable... your clarification of ablation along the entire length as an indicator of disequilibrium helps clear it up in my mind too. I'm still a little curious about the why question: why do A and B behave differently? But maybe that's just what's observed rather than any simple equation I can wrap my mind around.
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- I'll defer to you as well in moving the data sources stuff back down (but it does seem like the tipping point chart best stays with that, as you've done). In terms of illustration, I think referring to examples already in the article is good: it's already very picture-heavy as articles go, so adding more brings it too close to being an image gallery, IMO. Lulu of the Lotus-Eaters 17:22, 10 February 2006 (UTC)
Equilibrium again
OK, my attempt. I said (or the peer rev) "If a glacier cannot achieve a point of equilibrium through retreat..." - what isn't made clear here (not sure where to say it) is that as the glacier retreats (uphill; to a colder region) it becomes stabalised, since melt decreases but I don't think that was fully grokked. So...
Glaciers sit on slopes; and air gets colder as you go upwards. So if the net balance at the glacier terminus is negative (net balance = +ppn -melt +movement-of-higher-ice-down) the terminus retreats upwards. Higher up, the air will be colder, so melt will decrease, and to first order all the other terms are the same, so the terminus will stabalise at a new, higher position (and conversely, if the balance is +ve at the terminus, it will grown downhill, melt will increase and it will again stabalise). These are all dynamic balances, in that one year is never quite like the last, and of course there is a seasonal cycle in all of this. That sort of assumes that the changes in imposed temperature are slow enough that the glacier has time to come into equilibrium - it can take ?years?decades? for it to adjust. If the T changes quickly, the glacier can go out of equilibrium, and then it retreats/advances "in seach of" the new equilibrium.
Hans Oerlemans lecture notes (http://www.phys.uu.nl/~oerlemns/Oerlemans-simple%20glacier%20models.pdf) are quite helpful. William M. Connolley 20:24, 10 February 2006 (UTC)
- I think that a lot of this depends on the altitude gain...my understanding is that for every 1,000 feet above the altitude of 2,000, the temperature on an average is 1 to 3 degrees F colder than at the 2,000 foot margin. So if we are talking about valley glaciers with limited slope, this may not apply.--MONGO 20:53, 10 February 2006 (UTC)
- Oh no, its the imperialists! I can't do those units. Very roughly, 100m is 1 oC (generally somewhat less than 1 oC). If the glacier has a small slope, then it will have to retreat a long way (horizontally) to recover a small vertical change, and thus be very sensitive to T changes (Hans's notes mention this explcitly). William M. Connolley 21:58, 10 February 2006 (UTC).
- Gotcha:)...no, your comment is correct I believe as an altitude increase may lead to stabilization (equilibrium), but aside from a few examples this isn't showing up in the data. Take the New Guinea info for instance and Kilimanjaro...the glaciers there have retreated to a status that is nearing being disqualified as being in the realm of a glacier...and are either simply disappearing or are now simply snowfields. Is that about what you mean?--MONGO 01:38, 11 February 2006 (UTC)
- Oh no, its the imperialists! I can't do those units. Very roughly, 100m is 1 oC (generally somewhat less than 1 oC). If the glacier has a small slope, then it will have to retreat a long way (horizontally) to recover a small vertical change, and thus be very sensitive to T changes (Hans's notes mention this explcitly). William M. Connolley 21:58, 10 February 2006 (UTC).
Advance and retreat
The article says:
- In historic times, glaciers grew during the Little Ice Age, a cool period from about 1650 to 1850. Subsequently, until about 1940, glaciers around the world retreated as the climate warmed. Glacial retreat declined and reversed, in many cases, from 1950 to 1980 as a slight global cooling occurred. However since 1980, glacial retreat has become increasingly rapid and ubiquitous,
This is definitely what many people would think. But if you look at the recent Oerlemans Science papar (discussed at http://www.realclimate.org/index.php?p=129; see last fig) the glacier derived temperature is close to constant from 1600 to 1850; which implies that the glacier obs used for that study don't show growth (when averaged). The dip after 1940, and strong retreat after, fits the fig though. William M. Connolley 20:09, 10 February 2006 (UTC).
We could endlessly debate the timing of the Little Ice Age. The points is that glaciers were expanded during this period. There are many advances dated during the 1650-1800 period and few retreats. The glaciers were already expanded and the advances may have not been large, but the number of glaciers that reached their LIA maximum outside of the 1650-1850 period is small. Peltoms 23:11, 12 February 2006 (UTC)
- You miss my point. I'm not talking about the timing, but about the "glacial advance". If they were, why doesn't it show up in the Oerlemans work? William M. Connolley 20:36, 17 February 2006 (UTC)
Unused reference
I was looking for a good place to put the following reference as it was unused after some recent changes. I'll leve the link here in case we can add it...make sure we put it in the right sequence if readded to the cited references section.Longitudinal profiles of glaciers--MONGO 10:28, 11 February 2006 (UTC)
- This is the first published observation that longitudinal thinning along the entire length of a glacier is an unstable mode of retreat.Peltoms 23:13, 12 February 2006 (UTC)
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- I'll add it back and link cite.
Where we stand
It appears we are near to winding things up here...so a few questions
- Have all the issues raised by the peer review been addressed:[1]
- Are we finalized on article content?
- What does the article lack or what does it not need?
--MONGO 06:06, 14 February 2006 (UTC)
- I made a bit of a start at it, but I think for a featured article, it would be nice to get all the references into the proper templates. See Wikipedia:Template messages/Sources of articles/Generic citations. The web references in particular take a bit of effort to pull out what's author, what's publisher, what's title, etc.; but I think it's worth it to have the references structured as data. Of course, in some cases, I'm not really sure which template to use, or how to assign the fields. But in general, I think it would be great to nominate this for FA. Lulu of the Lotus-Eaters 06:41, 14 February 2006 (UTC)
- Thanks for that link...looks like a lot of work...I was trying to just make the references section appear with minimized link crawl, to reduce the blue lined "glare" if for no other reason.--MONGO 06:45, 14 February 2006 (UTC)
- I guess it's just a difference in aesthetic judgement, but I really dislike having the link be a lonely and easy to mis-click "^" all by itself. Moreover, web accessibility guidelines (such as US Section 508 or W3C WCAG) definitely push for descriptive text to be included inside external links. Lulu of the Lotus-Eaters 07:14, 14 February 2006 (UTC)
- Then that'll work for me...and save a lot of typing too.--MONGO 07:33, 14 February 2006 (UTC)
- I apologize in advance if this is painfully pedantic. But just to clarify my accessibility standards comment, take a look at WCAG Guideline 13. Provide clear navigation mechanisms, especially 13.1 Clearly identify the target of each link. I usually don't do this properly when I'm working quickly or in discussions; but it's actually a really good idea when you think about vision-impared or other text-oriented readers an article. Lulu of the Lotus-Eaters 07:49, 14 February 2006 (UTC)
- Okay, do many of the cited references need better source titles so a person knows everything up front...I'm getting confused...should we just simply state as the built in link something like one states e.g. Graph of glacial retreat, or should we get really descriptive and state author, title, etc.?--MONGO 08:26, 14 February 2006 (UTC)
- Nevermind, I see what you're doing now...--MONGO 08:40, 14 February 2006 (UTC)
- (edit conflict... but just for posterity) I think filling in as much of the "web reference" template as possible is useful; but as you notice, it's a bit of a PITA to do so... usually it means following the link to find much of the information. It's not really an accessibility issue, as such, but imagine if someone prints off the article: all that author/publisher/year/etc. is nice to have on the printout. I've started, and I'll chip away at it. Of course, if anyone else wants to do any, I'm very happy for that. But y'know, there's always room for getting better; the refs aren't broken as is, just less than the very best possible. Lulu of the Lotus-Eaters 08:43, 14 February 2006 (UTC)
- Oh, but you're doing great! Yeah, will help out...I think #13 is down already...Nasa Images...I'll get busy soon as you're done having fun.--MONGO 08:48, 14 February 2006 (UTC)
- Bedtime for me (4 a.m. EST), have at it :-). Lulu of the Lotus-Eaters 08:54, 14 February 2006 (UTC)
- Oh, but you're doing great! Yeah, will help out...I think #13 is down already...Nasa Images...I'll get busy soon as you're done having fun.--MONGO 08:48, 14 February 2006 (UTC)
- (edit conflict... but just for posterity) I think filling in as much of the "web reference" template as possible is useful; but as you notice, it's a bit of a PITA to do so... usually it means following the link to find much of the information. It's not really an accessibility issue, as such, but imagine if someone prints off the article: all that author/publisher/year/etc. is nice to have on the printout. I've started, and I'll chip away at it. Of course, if anyone else wants to do any, I'm very happy for that. But y'know, there's always room for getting better; the refs aren't broken as is, just less than the very best possible. Lulu of the Lotus-Eaters 08:43, 14 February 2006 (UTC)
- I apologize in advance if this is painfully pedantic. But just to clarify my accessibility standards comment, take a look at WCAG Guideline 13. Provide clear navigation mechanisms, especially 13.1 Clearly identify the target of each link. I usually don't do this properly when I'm working quickly or in discussions; but it's actually a really good idea when you think about vision-impared or other text-oriented readers an article. Lulu of the Lotus-Eaters 07:49, 14 February 2006 (UTC)
- Then that'll work for me...and save a lot of typing too.--MONGO 07:33, 14 February 2006 (UTC)
- I guess it's just a difference in aesthetic judgement, but I really dislike having the link be a lonely and easy to mis-click "^" all by itself. Moreover, web accessibility guidelines (such as US Section 508 or W3C WCAG) definitely push for descriptive text to be included inside external links. Lulu of the Lotus-Eaters 07:14, 14 February 2006 (UTC)
- Thanks for that link...looks like a lot of work...I was trying to just make the references section appear with minimized link crawl, to reduce the blue lined "glare" if for no other reason.--MONGO 06:45, 14 February 2006 (UTC)
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- I think Peltoms wishes to edit my draft of "Data sources", and I would welcome that. He has been tolerant of my edits of his words; he (or anyone) is welcome to a crack at mine. Also, one reviewer suggested putting some general comments or an introduction immediately after the "Data sources" heading. I have that on my to do list, but lacked inspiration on my last attempt. I'll try again tomorrow. Do we want some sort of summing up or conclusion? Thank you for keeping this moving. Walter Siegmund (talk) 06:51, 14 February 2006 (UTC)
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- I looked at Peltoms edits of "Data sources". (They were made on February 10 but I missed them because he wasn't logged in.) Anyhow, it is very much improved. I went over it again and hopefully didn't mess up the content too much. One thing I don't understand is why laser altimetry isn't the preferred method of measuring mass balance. My guess is that it is expensive, and I put that in the article, but it would be good to either confirm that or correct that comment. --Walter Siegmund (talk) 04:05, 15 February 2006 (UTC)
- Looks fine...I think if we add much more they'll dink us on the article length though.--MONGO 04:09, 15 February 2006 (UTC)
- I agree. I don't think I increased the length overall. I know that I deleted one sentence in the "Dating the moraines" section that I didn't think was necessary. (talk) 05:43, 15 February 2006 (UTC)
- Looks fine...I think if we add much more they'll dink us on the article length though.--MONGO 04:09, 15 February 2006 (UTC)
- I looked at Peltoms edits of "Data sources". (They were made on February 10 but I missed them because he wasn't logged in.) Anyhow, it is very much improved. I went over it again and hopefully didn't mess up the content too much. One thing I don't understand is why laser altimetry isn't the preferred method of measuring mass balance. My guess is that it is expensive, and I put that in the article, but it would be good to either confirm that or correct that comment. --Walter Siegmund (talk) 04:05, 15 February 2006 (UTC)
More on citations
On another topic, I moved some of the references into templates. I've got to applaud Lulu of the Lotus-Eaters and MONGO. That is a LOT of work. But, I have a question. I wonder why items 24, 31 and 35, citations of the journals Science and Journal of Geophysical Research, use the template Web reference instead of Journal reference or Cite journal? What am I missing? Thank you, Walter Siegmund (talk) 05:43, 15 February 2006 (UTC)
- Those were my additions and I probably messed them up...working on these footnotes this way...they look great in the end, but I feel like throwing my computer out the window...I'll get them straightened out later...thanks for pointing them out.--MONGO 05:50, 15 February 2006 (UTC)
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- I don't mind changing them (although it won't be tonight), but I didn't want to do it if there wasn't agreement to do it. Also, I used Journal reference for some of my edits tonight, so I wanted make sure they were ok. Thank you for taking a look. Walter Siegmund (talk) 05:58, 15 February 2006 (UTC)
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- As I say above, I'm not sure in every case exactly which template to use. So if anything looks wrong, by all means please fix it. And I also thank MONGO hugely for doing so many of them (more than I did). But indeed, I think they look fabulous with all this citation detail fleshed out, rather than just the title of the link. Lulu of the Lotus-Eaters 06:08, 15 February 2006 (UTC)
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Ooops... as I think Walter was alluding to, apparently "Journal reference" is now deprecated, adn "cite journal" is preferred. See Template talk:Cite journal. Aaaghh. Just when I think I get the hang of something, it gets deprecated. Oh well, it's not really so bad: other than using more "standard" lowercase names for the fields, it's pretty much a superset of the old one; so switching this is both non-urgent, and should be pretty simple to do (much easier than changing a web reference to a journal reference, which I did a few of). Lulu of the Lotus-Eaters 09:11, 15 February 2006 (UTC)
- I do think the references look very good. They should be much easier to maintain than naked URLs. Thanks for all your work on this.
- I wouldn't worry about Journal reference v. Cite journal. A robot will make the change if necessary. BTW, I asked at Journal reference why Wikipedia:Template messages/Sources of articles/Generic citations listed Journal reference. Walter Siegmund (talk) 14:11, 15 February 2006 (UTC)
In terms of laser altimetry it works over big smooth ice sheets over a span of time, but for small glaciers which such dramatic topography it is not efficient. It is costly too to fly an entire glacier creating the map on the correct date each year.Peltoms 16:57, 15 February 2006 (UTC)
- Thanks for the explanation. That is a big help! Walter Siegmund (talk) 18:59, 15 February 2006 (UTC)
In terms of the references what is the preference particular journals or online sources. I know plenty of journal refernces that can replace the online sources we have. I did not do this because most people have no access to them, but if they are online too that is accessible.Peltoms 17:00, 15 February 2006 (UTC)
- Wikipedia:Reliable_sources#Cite_peer-reviewed_scientific_journals_and_check_community_consensus seems to clearly indicate that peer-reviewed scientific journals are preferred sources for scientific articles. The editors of global warming have a clear preference for journal articles.
- Personally, I think it is important to have both sorts of sources since not all readers have subscription access to online journals, but, equally important, not all readers will have good access to web sources, e.g., if they are reading a paper or CD copy of the article. I'd hate to see a web source replaced by a subscription only journal article, but if the journal article could be cited also, that would be splendid. But these are just my own thoughts, not a Wikipedia guideline. Walter Siegmund (talk) 18:59, 15 February 2006 (UTC)
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- FWIW, there's no reason multiple versions can't be indicated in the same footnote, if needed. So a particular note could say: "{{cite journal ...}} (for an online draft, see {{Web reference ... }})". Of course, doing such extra work is distinctly non-urgent after all the work of getting the full refs up in the first place :-). Lulu of the Lotus-Eaters 19:03, 15 February 2006 (UTC)
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- Journal refs are clearly best, except that many people can't access them :-). What I've done elsewhere is to link to the "official" ref (say, science or nature or...) and also link to the authors pdf available online, where it is. William M. Connolley 21:49, 15 February 2006 (UTC).
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Tipping point again (and graphic formats)
I'm still a little concerned about the tipping point arrow in the glacier mass balance chart. The chart is great, but the meaning of that pointer is not discussed in the article (and I don't really understand the explanation on the talk page, since there seems to be a generally negative inflection to the curve).
I wonder if editors are strongly attached to that pointer; I'm inclined to think it would be better without that side issue. Or maybe an explanation of why the arrow points exactly there would show why it's important to include. I could touch up the JPG file to erase that arrow, but better might be if Peltoms could export the original format without it. I presume the original vector image would make it easier to erase an element like that.
Oh... also on those lines, both of the graphs are really in the wrong format. JPG is only the right thing for continuous tone images like photos. Either PNG, or even SVG, would be better for a chart/graph. It looks like very low JPG compression was used, but I can still see some slight compression artifacts. Lulu of the Lotus-Eaters 19:16, 15 February 2006 (UTC)
- I'm not keen on "tipping point": its an over-used and under-explained concept in general. I'd rather it wasn't there, unless justified (by, say, the WGMS reports). In certain situations, for an individual glacier, there could perhaps be a point at which (perhaps ice-albedo feedback) knocks it over some threshold. But in general, since glaciers have a strong negative feedback (retreat uphill) available, there is no tipping point. At least as far as I'm aware. If it is to stay, it needs a good justification. William M. Connolley 21:47, 15 February 2006 (UTC).
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- I converted the image to PNG and manually whited-out the "tipping-point" thing. However, if Peltoms can provide me with the vector original image, I can do a better job with this. Once I zoomed in a bunch to paint the pixels, I could definitely see a lot of compression artifacts from the JPG version. Lulu of the Lotus-Eaters 02:08, 16 February 2006 (UTC)
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- I'm not seeing this uphill negative aspect reflected in the data as compared to overall genral retreat. While it has been observed and reported, it is not apparently universal and may be more commonplace in the most southern and northern latitudes, leaving mid latitude glaciers without a point at which they can reestablish equilibrium. I am also finding the explanation of the tipping point ambiguous.--MONGO 22:06, 15 February 2006 (UTC)
The tipping point seems to be a sticking point just as the description of the 1000 year termperature records hockey stick description. The WGMS is a reporting agency not so much an analysis agency. However, the change in mass balance and terminus behavior at the noted moment in time, tipping point, has been noted by many authors Dyugerov and Meier, myself, Cogley, Thompson, Haeberli etc., as a significant change in the overall health of glaciers globally. Connolley is not correct in stating that there is typically not a tipping point or threshold beyond which a glacier cannot recover. In fact these thresholds have been noted for many glaciers and in reports referred to in this article. In general the conclusion is that the glaciers in location x are simply not likely to survive. I strongly recommend that we make note of the important change in slope that has led to the increase in glacier retreat, which I called the tipping point. If you wish to label it as simply increased negative balance trend, fine.Peltoms 15:55, 16 February 2006 (UTC)
Confusing
I find this second paragraph from the section "Dynamics" confusing: A glacier tends to reestablish equilibrium through retreat, losing the highest ablating low elevation terminus areas. Since higher elevations are cooler than lower ones, the disappearance of the lowest portion of the glacier reduces overall ablation, thereby reestablishing equilibrium if the glacier is not in disequilbrium. If a glacier cannot retreat to a point where accumulation and ablation are balanced, it is in disequilibrium with the climate system. Such a glacier will melt away with a continuation of this climate.
"Highest ablating low elevation terminus zone"...needs a conversion into something that can be more easily understood by those unfamiliar with this evidence. The second sentence is confusing me as well and I think it needs to be clarified or at least simplified. We also need to attribute the glacier mass graph and disclose where that came from and what the data is based on. Just a few thoughts.--MONGO 01:39, 16 February 2006 (UTC)
I tried to clarify the aforementioned paragraphPeltoms 16:57, 16 February 2006 (UTC)
- Thanks, it reads a lot easier now.--MONGO 18:54, 16 February 2006 (UTC)
Holocene glacial retreat
I stubbed Holocene glacial retreat pursuant to the discussion above. I added enough low quality verbage that it is unlikely to be deleted. I don't know much about the topic, except that plenty of information is available and that it was responsible for forming or modifying much of the modern landscale in northern North America and Europe. Should it be linked to this article right away. Or would it be better to wait for meaningful content? Best wishes, Walter Siegmund (talk) 19:59, 17 February 2006 (UTC)
Punchlist
Please add items below...
- MONGO thinks that we might be asked to shorten the article (see my talk page). I don't mind moving the Data sources section into a new article (Glacier metrology?) if people think that would improve this one. Should we do it now? Walter Siegmund (talk) 07:37, 18 February 2006 (UTC)
- I'll defer to the people who actually know this stuff for real judgement, but one option if the page is to be refactored is simply to make obviously child names, e.g. Glacier retreat (data sources). That's used a number of places, and it makes sense to me if a topic really is directly in support of the parent topic, but not so much as to warrant disrupting overall flow of the parent. Lulu of the Lotus-Eaters 08:34, 18 February 2006 (UTC)
- It bugs me a bit that the article just ends. Should there be some sort of summing up, perhaps? Walter Siegmund (talk) 07:37, 18 February 2006 (UTC)
- I originally had a summary subheading, but couldn't figure out a way to tie all the parts together...it's probably not that hard to do...I'll have a shot at it...edit it mercilessly.--MONGO 09:05, 18 February 2006 (UTC)
- Thank you for doing this. Walter Siegmund (talk) 05:43, 20 February 2006 (UTC)
- I originally had a summary subheading, but couldn't figure out a way to tie all the parts together...it's probably not that hard to do...I'll have a shot at it...edit it mercilessly.--MONGO 09:05, 18 February 2006 (UTC)
- Are we comfortable with the objectivity of the article? People have pointed to the advancing glaciers of Norway and New Zealand to argue against the ubiquity of glacier retreat. Is that argument notable enough to mention in the article? Walter Siegmund (talk) 07:37, 18 February 2006 (UTC)
- How about these link for New Zealand:[2] dated 2/16/06 [3]--MONGO 09:55, 18 February 2006 (UTC)
- Those seem notable enough to me for inclusion. Thank you for finding them. Walter Siegmund (talk) 00:22, 19 February 2006 (UTC)
- How about these link for New Zealand:[2] dated 2/16/06 [3]--MONGO 09:55, 18 February 2006 (UTC)
- People have argued that the observed glacier retreat is unrelated to anthropogenic effects. We don't say much about this, but maybe we should cut it further? It seems to me that arguments about anthropogenic climate change are best handled at global warming.
- I 100% agree that the anthropogenic issues really have no need for discussion here. Global warming is obviously one of the major causes of the pattern of glacier retreat (changes in precipiation patterns, etc. may act as intermediate causes, of course). But even if human "greenhouse gas" emissions were irrelevant and it is all part of some inevitable natural cycle, the glacier retreat itself is the same. (yeah, the prior thing is a stupid petroleum industry story, unfit for telling children at night... but we need not get into that here). Lulu of the Lotus-Eaters 08:34, 18 February 2006 (UTC)
- I looked long and hard for citable web based evidence of glacier advance...I came up with not much more than new stories that lacked a primary contact that seemed sufficient. I do remember stumbling into rock glaciers in Colorado and elsewhere that had only recently been discovered. The one at the base of the east flank of Longs Peak is apparently a thousand feet thick..supposedly. I walked right by it twice and it didn't look like a glacier to me, but that is what they say, that thousands of people had been within and on top of a rock glacier and didn't even know it. [4] The comment that the Glacier on Mt. St Helens was brought up as being in a state of advance, but I can't find any literature to prove it, and the recent resurgence of the volcanic activity there has actually spilt the glacier in two. Looks like I need to do some more research. There is no hurry on getting this to feature status...if we can improve it, then I am for that.--MONGO 09:05, 18 February 2006 (UTC)
- The 1980 eruption of Mt. Saint Helens left a large crater with a north-facing breach. A glacier fed by avalanches from the remaining crater walls developed in this new crater. The renewed activity dating from 2004 has melted and buried part of the glacier. I don't think this example is relevant to the article topic. Its growth was due to the appearance of a favorable site that was not already filled with a glacier.[5] Walter Siegmund (talk) 00:22, 19 February 2006 (UTC)
- The Africa section reads, in part, with regard to Kilimanjaro, "other factors besides global warming may be responsible...", but goes on to cite climate change effects. Isn't global warming merely a convenient term for anthropogenic climate change? Walter Siegmund (talk) 07:37, 18 February 2006 (UTC)
- I would think here that the indirect effects aren't "global warming" per se. By analogy, the desertification of the sahara is hardly a matter of temperature change as such, but rather a loss of precipitation. Quite likely, the precipiation patterns are connected by several steps to overall warming, but presumably global cooling would also reduce precipitation in some other locations too, no? I don't think we should over-claim where we do not need to. Lulu of the Lotus-Eaters 08:34, 18 February 2006 (UTC)
- Yeah, please feel free to reword that...I stumbled on the reduced precipitation on Kilimanjaro, and the citation that is also a cuase of glacier retreat there, kind of late in the game, but felt it should be noted.--MONGO 09:05, 18 February 2006 (UTC)
I as someone very familar with all the glacier terminus research, this article deals with if very fairly. We have not ignored advances, in the Norway section etc. if glaciers were advancing this is so noted. The fact is that as of the last decade it is hard to find even 1% of the worlds glacier advancing, thus a fair reading on the topic will give little space to them. We have noted correctly that glacier retreat is due to global warming, and not gone past that point, which is fine. I must say we have commented time and again on glacier retreat without going into the details of it for particular glaciers, these details would obscure the facts. I thus must point out that the added section on Kilimanjaro is not appropriate. We are giving a detailed look here and not elsewhere, secondly you have misread the research. I have worked closely in the past with Kaser and Hardy two of the authors of the cited papers, and neither would agree with your statement. It is clear that ablation used to occur via sublimation only on Kili but now occurs via actual melting producing meltwater, due to higher temps. Of course reduced ppt can and does play a role. For this reason I am removing the Kilimanjaro paragraph. I could write a chapter on the reasons for retreat for each glacier in each section and on no glaciers is it all about temperature rise.Peltoms 13:40, 20 February 2006 (UTC)
- Thank you for giving this a careful read. What should we do about de Freitas? I'm assuming that you don't think his views are notable (WP:N) enough to warrant comment, e.g., "It's an environmental condition that attracts attention, but to link it to global warming is such a leap that is shows what I would consider a naive or simple understanding of events." [6] It may give this view undeserved prominence to quote Scientific American or another other reference indicating that de Freitas' views have little support in the scientific community and that he was an editor of Climate Research a minor journal that subsequently disavowed his editorial work (publishing a flawed paper by Willie Soon and Sallie Baliunas) amid three resignations from its editorial board? [7][8] Is it a good idea to confront this issue directly or to dismiss it implicitly by not talking about it? What does WP:NPOV require in this case? Google finds 696 instances of "de Freitas" "global warming". [9] I looked at Global warming controversy; it does not discuss de Freitas or Soon and Baliunas. I don't think we should duplicate any part of the global warming controversy article. But, I wonder if it suffices to mention that there are those who deny that recent warming is largely human-caused and link to global warming controversy. Walter Siegmund (talk) 21:44, 20 February 2006 (UTC)
- As I mentioned, I looked long and hard for any evidence that could be easily linked via the web for an argument that the cause may be changes in weather patterns, or anything else other than global warming. I recognize that changing weather patterns=global warming for the most part. My addition to Mount Kilimanjaro was for this explicit purpose...to play devil's advocate, and it is not unlikely due to my laymans knowledge that I misinterpreted the evidence I cited. Kilimanjaro is an easy target for information because there is a lot of it out there, hence the lack of cross examination for all the glaciers worldwide. I also added the information on the Franz Josef glacier in New Zealand, how that was expanding and that it was attributable to increased snowfall and a cooler summer due to el nino. We were asked to examine the glaciers in places like New Zealand and Norway as they were minor examples of glacier advance. My attempts were just to try and make sure we are following a NPOV argument and not a POV one. That is critically important in this endeavour.--MONGO 01:37, 21 February 2006 (UTC)
Glaciers care more than just about temperature, we have noted key advancing glaciers that in fact reflect the fact that increases in winter snowfall or a change in terminus dynamics can lead to advance. What is amazing is how dominant retreat is, given the importance of other factors. That indicates that around the world the temperature signal dwarfs everything else. I do not think we need to go into the global warming controversy. We can just point out as we do that global warming is driving the retreat.Peltoms 11:52, 21 February 2006 (UTC)
- I have to agree...I have looked really hard for reliable witness to demonstrate the opposite of the bulk of our findings and there simply isn't any that is worth mentioning. I wish there was to be quite honest, as these changes are rather alarming to say the least. We need to find more in regrads to Asia...I have looked with little success...do we have a reference for some of the information in the Asia section? I found only one substantive link that was web based...if there is written evidence, it would be nice to be able to cite it and put the reference in the cited references at bottom. I'll look more tonight for information on Asia.--MONGO 14:09, 21 February 2006 (UTC)
I added a bit on the Himalaya. The source documents for this research are available from the United Nations.Peltoms 16:58, 21 February 2006 (UTC)
Reorganization of article
I would like to propose the following reordering of the material in the article.
- Move Greenland to the end of the Arctic Ocean section and rename that section Arctic
- Put Antarctica after Arctic
This would place the introductory remarks of the Greenland section, a description of the vast polar and subpolar ice sheets, near the Antarctica section to which they also pertain. Currently, Greenland is between the mostly temperate mountain and valley glaciers of Europe and North America and the tropical and subtropical mountain glaciers of Africa, Asia and Oceania. It seems to me that it is better grouped with the Arctic islands and Antarctica at the end of the article. While Greenland does extend as far south as 60 degrees N, it is mostly above the Arctic Circle, so it is fair to call it Arctic, or so I would think. I put Antarctica at the very end so that there is a rough progression in the article from small mountain glaciers to enormous continent-scale ice sheets.Walter Siegmund (talk) 05:43, 20 February 2006 (UTC)
- Okay, sounds good.--MONGO 07:42, 20 February 2006 (UTC)
- Done, relocated cited references as well.--MONGO 08:04, 20 February 2006 (UTC)
- Good work on the summary I added a bit of detail, and took out one sentence so the length remains unchanged. The Alaska section looks just a bit long, so I will look to shorten thatPeltoms 13:49, 20 February 2006 (UTC)
Nominated
I nominated the article for Featured Status...links to watch: Wikipedia:Featured article candidates/Glacier retreat and Wikipedia:Featured article candidates--MONGO 08:10, 21 February 2006 (UTC)
Graphs
We need to better illustrate the graphs...as asked in the nomination process:what do the red and black dots represent and where was the information that the graphs demostrate come from. I'll try and research more on it tonight. I thnk we need to trim the Alaska section significantly...I hate to lose data, but I'm for the creation of a daughter article that just discusses Alaska and a summary of the information here, with a few examples. The rest of the sections seem fine, and I'll continue to try and locate more on Asia.--MONGO 03:31, 22 February 2006 (UTC)
- I created a slightly touched up version of the alpine retreat from data Peltoms provided me (I now have the glacier retreat data too... and will try to create a tweaked version of that chart). But I cannot provide citation information for the data itself. Hopefully Peltoms will add the complete citation to the charts. The red and black dots look fairly obvious to me, but if I can get the graph created afresh, I'll add more explicit caption as to the meaning (years, a range of data or confidence interval for the single-year data, a single average for cummulative). Lulu of the Lotus-Eaters 04:06, 22 February 2006 (UTC)
I shortened Alaska some and Asia looks good in its length now I think. I have much more I could add to any of the sections. But I think the balance is good. The mass balance graph has been changed and I am sure Lulu of the Lotus-Eaters will make further improvements to it.
- Actually, I'm afraid I probably won't do so. I got a large chunk of raw data from Peltoms, but exactly how the charts are derived from the data is not entirely obvious to me once I looked at the spreadsheet. So I think I'm just going to leave the mass balance chart as-is. Or maybe just add a slight extra caption in a bitmap editor, rather than try to re-export from the source data. However, we definitely want to clarify the citation/source of the data. Lulu of the Lotus-Eaters 18:19, 22 February 2006 (UTC)
- Yeah, we'll have to I'm afraid...Peltoms...can you summarize it in a sentence? here and then we can try and disseminate it into the text of the image?--MONGO 20:23, 22 February 2006 (UTC)
- The reference is accurate and the image caption is concise. I do not think anything needs to be added to the mass balance graph. Note the lack of detail explaining the year notations on photographs for comparison.Peltoms 13:19, 23 February 2006 (UTC)
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- Yes, I agree. The mass balance chart is now well annotated, with a good citation. Can we provide similar information for the Alpine one? Thanks. Lulu of the Lotus-Eaters 21:48, 23 February 2006 (UTC)
- I think the article reads so much better after all of the edits. I still do not see how the mass balance methods section helps the article overall. Do any of you see it as important. Peltoms 16:33, 24 February 2006 (UTC)
- I started the mass balance methods section because I thought it was an exception to much of the rest of research related to global warming, e.g., oxygen isotope ratios, climate models, etc., in that the techniques are straightforward and easily grasped, for the most part, by the nontechnical reader. I was especially intrigued that useful data can be obtained by emplacing poles in ice or by pushing probes in snow. Also, I'm hoping to get some pictures this summer of annual layers on crevasse walls. Often, it is hard to illustrate scientific data acquisition, and again, I thought this was an exceptional example. That said, I think it is important to focus on Peltoms point of whether this section helps the article overall. I would not object if others prefer moving it into a subarticle. Walter Siegmund (talk) 18:56, 24 February 2006 (UTC)
- Are we talking about the entire dynamics section...leaving just a couple of sentences to summarize and then linking to a subarticle?--MONGO 19:30, 24 February 2006 (UTC)
Theory to top
One of the FA nomination commentors suggests a reorganization where the "data sources" material moves near "dynamics" to group the theoretical stuff together near the top. I had made the same change earlier, but deferred to one of you experts on reverting it. However, as the article has progressed, I continue to think that organization makes better sense. Dry and theoretical is exactly what I want at the start, as a reader :-). As is, reading the theoretical material means reading a bit at the top, then jumping to the very bottom for the rest.
What do other editors think? Would you object to me putting it back this way? I'm not sure what the section would be called, maybe "Theoretical background" or something like that. Or maybe something with the word "Glaciology" in it. Lulu of the Lotus-Eaters 08:46, 23 February 2006 (UTC)
- Thats fine...don't forget the citations replacement in order....:-(...it's a pain.--MONGO 08:54, 23 February 2006 (UTC)
- How about dynamics of glacial mass balance?--MONGO 08:55, 23 February 2006 (UTC)
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- I wonder if we'd be better going to m:cite.php referencing? For example, here's a rather trivial article that I put in the new ultra-hip referencing style into: [10] Lulu of the Lotus-Eaters 09:50, 23 February 2006 (UTC)
The dynamics sectiion is not about glacier mass balance so that is not appropriate. I do not agree with moving the dry stuff to the top, because I think most readers are not like you and want the meat first, but I will defer. I would suggest as I have before that we define mass balance well as we have, but not explain how to measure it, it is off topic and complicated and we can create an article for that after. I have completed more mass balance measurements on more glaciers than anyone in the world, and yet still think it should not steal any focus here from terminus. Peltoms 13:23, 23 February 2006 (UTC)
In all honesty..my belief is that a lot of the "dry stuff should have just a very brief one paragraph overview and be sent to a "daughter article" that is linked to this one. I guess I've learned enough about the terminus and mass balance discussion that I prefer the meat of the factual evidence first, but I went and changed it anyway. I think I'm just partial to the pictures so I prefer to see that closer to the top and put the mass balance and terminus sections all at the bottom.--MONGO 13:59, 23 February 2006 (UTC)
- I did a fair bit of editing assuming that mass balance, equilibrium and disequilibrium were defined near the beginning of the article. So I would object to a reorganization that meant having to revisit those edits. Also, I wonder if the first occurrances of these terms should be in bold-face to make it easier for the reader to look them up if he/she skipped the dry sections on the first read?
I changed the description of the climate of Africa to tropical and subtropical from temperate. I'm sure that is correct, but it's read that way for a long time. Walter Siegmund (talk) 17:22, 23 February 2006 (UTC)
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- I haven't (yet) seen exactly who made which change, but glancing at the article, I think it definitely reads better with the first section having:
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- 1 Glacier dynamics
- 1.1 Data sources
- 1.2 Mass balance
- 1.3 Terminus location
- 1 Glacier dynamics
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- And the data from individual continents following that. That said, I would certainly not object to having much of that material split off into a daughter article, and just give a brief pointer to what readers will find in that daughter. But the pointer itself should still be in that top section. And certainly the stuff on (dis)equilibrium should stay in the main text (though a more extensive explanation might be added to the daughter; but what we have now is about the right length for this main article). Lulu of the Lotus-Eaters 19:26, 23 February 2006 (UTC)
References again
I'm kinda not so happy of the notion of using php.cite style. Writing the references inline on occurence indeed groups them where needed, but disrupts the appearance of paragraphs in the edit window. On the other hand, maintaining the order or references and notes seems like a real PITA.
I wonder what editors would think of using Harvard style referencing. We could list all the citations in a sensible alphabetic order by author (I know some web references are hard to say who's author; but I think we can find something), and not worry about the correspondence order between notes and references. For a simple sandbox example, if you haven't used this, see: User talk:Lulu of the Lotus-Eaters/Ref practice. If the idea flies with other editors, I'll do the work of transforming these... it's pretty straightforward compared to the much greater effort of putting everything into the reference templates (which we would still keep). Lulu of the Lotus-Eaters 20:00, 23 February 2006 (UTC)
- Harvard is my personal pref William M. Connolley 20:57, 23 February 2006 (UTC)
Child article
Reflecting what seems to be general consensus, I spun off a child/sibling article Glacier dynamics. I believe I left in about as much as we need for this article, but please feel free to improve. Also, if you think the child needs better context or an altered lead, I appreciate your help. I think it mostly works though.
Also notice that I implemented that Harvard referencing in the child, which I think looks nice. Lulu of the Lotus-Eaters 21:09, 24 February 2006 (UTC)
- I've moved this to Glacier mass balance following discussion on the child page. Hope thats OK, can be undone if not. William M. Connolley 22:57, 24 February 2006 (UTC)
Questions posted to my talk page
Reposting this from my usertalk and I can both answer them here (as can anyone else) and in my usertalk.
For its FAC, I am starting a fact/reference check on Glacier retreat. As the proponent, may I posted questions here on your talk page? I'll assume you said 'yes' and begin (you can move this conversion to the FAC page or other talk page if you like):
- First, I am glad you (or someone) created a section on Glacier mass balance, it was slow going with that data sources section. Unfortunately, this alteration messed up the references. If you don't have a problem with it I will re-format them to the new m:Cite/Cite.php system so they will order themselves.
- In "Alps" the 1995-2000 edition of something (a report?) is referred to and its results given but I cannot find the reference. Is it on the WGMS website? --maclean25 02:38, 25 February 2006 (UTC)
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- I corrected or at least made the link more direct...one must open a pfd doc to examine the evidence and I can't direct link it since it is a doc that must be saved to your computer.--MONGO 05:52, 25 February 2006 (UTC)
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- User:Lulu of the Lotus-Eaters is to be credited with creating the Glacier mass balance article...otherwise I did little editing in the mass balance section in this article, maybe a little copyediting but that is all. As far as using m:Cite/Cite.php for the references...that is fine with me, but at least two editors above have indicated they may prefer Harvard style referencing instead. I'll look at the "Alps" comment and citation.--MONGO 03:28, 25 February 2006 (UTC)
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- Yeah... having successfully used the Harvard refs in the Glacier mass balance article, I now feel fairly strongly that Harvard is more maintainable than m:Cite/Cite.php for the style of bibliographic references we use. If we used actual comments in footnotes I might feel otherwise, but for simple citations, inline cite.php can look awkward when editing. Lulu of the Lotus-Eaters 03:36, 25 February 2006 (UTC)
- Is there a BOT someone runs that can be used to do this conversion, at least in the section at the end of the article under cited references? --MONGO 03:39, 25 February 2006 (UTC)
- Ah... my kingdom for a bot! That was much more work than I had hoped. But I don't think a bot could have done it, since the old ref names are mostly not the same as the author name that I wanted to use in the link; it took some judgement cite-by-cite. Still, I think this is quite pretty. Lulu of the Lotus-Eaters 05:00, 25 February 2006 (UTC)
- Excellent work there Lulu...I must admit, it was going to be several days before I had the energy to devote to the conversion and I appreciate all your hard work!--MONGO 07:43, 25 February 2006 (UTC)
- Ah... my kingdom for a bot! That was much more work than I had hoped. But I don't think a bot could have done it, since the old ref names are mostly not the same as the author name that I wanted to use in the link; it took some judgement cite-by-cite. Still, I think this is quite pretty. Lulu of the Lotus-Eaters 05:00, 25 February 2006 (UTC)
- Is there a BOT someone runs that can be used to do this conversion, at least in the section at the end of the article under cited references? --MONGO 03:39, 25 February 2006 (UTC)
- Yeah... having successfully used the Harvard refs in the Glacier mass balance article, I now feel fairly strongly that Harvard is more maintainable than m:Cite/Cite.php for the style of bibliographic references we use. If we used actual comments in footnotes I might feel otherwise, but for simple citations, inline cite.php can look awkward when editing. Lulu of the Lotus-Eaters 03:36, 25 February 2006 (UTC)
- "By 1999, a full 96% of these glaciers were found to be retreating" does not the reference say 89% retreating and 96% not advancing?
- Providing a reference for confirmation/further reading of the "In 1892, a similar dam burst thereby releasing some 200,000 m³ (260,000 yd³) of water from the lake of the Glacier de Tête Rousse, and killing 200 people in Saint Gervais." would be useful. --maclean25
- I have now added a cite that supports this comment--MONGO 07:59, 25 February 2006 (UTC)
- Ok, that reference answers a lot of questions I had. Once I made the connection between User:Peltoms and Mauri S. Pelto, Director NCGCP, things started to make more sense. I was getting really confused because I could not figure out how the stated info in this article was being drawn from the sources. For instance, where in the FLUCTUATIONS OF GLACIERS 1995–2000 report is the "In Switzerland 103 of 110 glaciers examined were retreating...." paragraph coming from? Then I saw that actually came from Peltoms' own article at NORTH CASCADE GLACIER CLIMATE PROJECT where he makes the connection (even though I still don't see where - what pages - it is coming from in the report). We are really lucky to get such an expert working on Wikipedia. I have the same problem with other sources such as Norway's and Sweden's, in that I cannot figure out how the graphs(?) translate in those numbers. Could someone please explain how to do this (or provide a link to a brief tutorial)?
- The online version of the reference (SFIoTZ) seems to be dead. --maclean25
- Now fixed...the Glacier cited can also be linked off the list I cited, leading to an image of the glacier.--MONGO 20:02, 25 February 2006 (UTC)
- "The Snows of Kilimanjaro may be gone in less than 30 years." -- I don't get it, is this a pun?
- In "Alaska ", "...when comparing the periods from 1950 to 1995 (-0.7 m (2.3 ft)/yr) and 1995 to 2001 (-1.8 m (5.9 ft)/yr).(Arendt, et alia)" -- I got -0.52 m/yr from the reference, not -0.7m/yr.
- "Of 2000 glaciers observed, 99% are retreating." where does this come from? It mentions a 2005 aerial survey of Alaskan coastal glaciers but I cannot find it is the references, only mentions of it like in [11] and [12]
- "A report from March 2005 indicated that there is almost no remaining glacial ice..." -what report? the Guardian article?
- I think the "NASA. Melting Snows of Kilimanjaro" online reference went dead.
- What is the purpose of the (Thompson, et alia) reference?
- I believe the Kilimanjaro paragraph has potential for more discussion on what is driving the recession. Consider [13] for future editing. Also, consider referencing the 75% recession claim to [14] --maclean25
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- Snows of Kilimanjaro was just an attempt at prose in regards to Ernest Hemingway's book written in the late 1930's that is somewhat highly regarded...do you think it is inappropriate?--MONGO 07:09, 26 February 2006 (UTC)
- I have commenced a complete rewrite of the Alaska section and will address your concerns on the Kilimanjaro section shortly.--MONGO 08:12, 26 February 2006 (UTC)
- The Thompson , et alia reference pertains the the sentence immediately before the reference.
- We already did look at increased solar radiation as a result of the glacier retreat on Kilimanjaro and this was dismissed as the same thing as climate change...or global warming essentially.--MONGO 08:47, 26 February 2006 (UTC)
- This link [15] is helpful and looking at how to incorporate it.--MONGO 09:01, 26 February 2006 (UTC)
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- "In examining 612 glaciers in China, 50% were found to be retreating in 1970..." - this appears to have come from page 56, but is the 50% figure stated in the article correct? Please confirm.
- "Gangotri Glacier, which is one of the primary sources of water for the Ganges River, has been retreating 30 m (100 ft)/yr since the year 2000." - Page two of the ref says 30 m in 1998, but page 30 gives a more an average of 34 m/yr between 1970-1996.
- Seems to be conflicting sources: the ref does indeed say "20 glacial lakes in Nepal and 24 in Bhutan have become potentially dangerous" but the previous reference says on page 26 that "26 lakes in Nepal were identified as potentially dangerous lake". No big deal, just interesting.
- "Chacaltaya Glacier in Bolivia ... between 0.6 (1.9 ft) and 1.4 m (4.6 ft) of ice was lost per year" the ref says "water", not ice. I'm still new at this, is there a difference?
- yes, ice has a different density than water so a change of one foot in ice thickness is 0.9 feet in water equivalent lost thicknessPeltoms 02:46, 28 February 2006 (UTC)
- Where (or which page) of the ref does this statement come from: "between 1977 and 1983, a glacial retreat of 7% occurred.(USGS4)"? --maclean25
- I corrected the 612 glaciers for China to include the years between 1950 and 1970. For South America, I wasn't able to find the number 7% between 1977 and 1983, but it may be derived from the data and graphs on this page in the same article: [16]. I am not sure if the terms ice and water are completely interchangeable, I'll defer that to one of the other editors here. I can add that 34% figure, 1970-1996 for Gangotri Glacier.--MONGO 13:37, 27 February 2006 (UTC) Know they are not interchangable, though the can be quickly converted again ice has a different density than water so a change of one foot in ice thickness is 0.9 feet in water equivalent lost thicknessPeltoms 02:46, 28 February 2006 (UTC)
- "...1939 and 1962.(Allison and Peterson)" does not seem to connect to the notes at the bottom of the page (sp?).
- "The Larsen Ice Shelf lost 2,500 square kilometers (965 miles²) of its area from 1995 to 2001." I was unable to confirm this with any sources but found more detailed breakdown of the retreat here and here for 1995 + 1998 events.
- The Larsen broke up in two blocks: Larsen A, then L-B. See [17] (a bit crappy, but confirms the 2000 km2) for the L-A. This has some info etc. For L-B [18] would do. William M. Connolley 20:14, 2 March 2006 (UTC)
- "It has also accelerated from 20 m (65 ft)/day to 32 m (104 ft)/day.(Howat)" - but Howat ref says "the Helheim glacier has sped up from around 70 feet per day to nearly 110 feet per day"
- Concerning the last two sections, there are a few claims that may need some backing:
- "In Norway, the Alps and the Pacific Northwest of North America the impact on hydropower is substantial." might need backing
- "glaciologists and those in related professions have been informing the scientific community ..."
- "Glaciologists agree that the current trend of rapid retreat is likely to continue ..." -maclean25 19:21, 2 March 2006 (UTC)
- Maclean25, I've temporarily moved a copy of this article to my userspace for major overhaul. I will still address any concerns you have but in the newer version I am working on...User:MONGO/gr thanks for all your questions as they have made the article better.--MONGO 12:49, 3 March 2006 (UTC)
Footnote names
I have tried to use academic-style last names for footnote/endnote links, rather than simply mneumonic values. So I recently changed "MSPelto" to "Pelto5". Normally, in academic notes, you'd indicate year for multiple sources from same author: "Jones 1987", "Jones 1995a", "Jones 1995b". Unfortunately, however, for many of the web sources the year is unclear to me. Rather than append a letter for disambiguation, I used a number. "Jonesa" might read like an actual name (and "Jones a" looks odd to me); or more concretely, "Peltoa" and "Peltob" look plausible as names, so I made them "Pelto1", "Pelto2", etc. In a number of cases, the "author" of a citation is an organization, in those cases I use the capitalized acronym of the organization (whether or not it normally goes by an acronym): e.g. "USGS". Lulu of the Lotus-Eaters 18:28, 25 February 2006 (UTC)
- Thanks for that, it's still a little Greek to me, so I'll try and make sure I read the Harvard style footnoting for future referencing.--MONGO 19:52, 25 February 2006 (UTC)
The first sentence
Currently the first sentence of the article reads: "Glacier retreat is one of the most important topics in the field of glaciology. Worldwide there has been..."
However, Wikipedia:Guide to writing better articles#The first sentence tells us to make the opening sentence "give a concise, conceptually sound definition that puts the article in context."
To improve on the current opening, how does this sound: "Glacier retreat is the process by which glaciers lose volume or surface area due to a lower level of accumulation than ablation of precipitation. It is one of the most important topics in the field of glaciology which has recorded a general, worldwide, reduction in size of glaciers. This has been especially pronounced in Himalayas, Alps..." What are your thoughts? --maclean25 19:57, 2 March 2006 (UTC)
- Take a look at the first couple of lines now and let me know what you think.--MONGO 08:40, 6 March 2006 (UTC)
A map
You guys can probably find a good way to use this.
Dragons flight 10:01, 4 March 2006 (UTC)
- Whoa...now that's is nice...I'll see if I can fit it somewhere on the newer version of the article. How'd you do that...what software are you using?--MONGO 11:44, 4 March 2006 (UTC)
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- Matlab and Adobe Illustrator. Dragons flight 20:55, 4 March 2006 (UTC)
- Nice map, but where's Antartica? It's kinda relevant... – Doug Bell talk•contrib 12:17, 4 March 2006 (UTC)
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- As noted on the image description page, I limited it to sites that had been measured at least 5 times since 1970. According to Dyurgerov and Meier (2005), none of the glaciers on the margin of Anarctica have been measured more than 4 times since 1970. Dragons flight 20:55, 4 March 2006 (UTC)
- It is a beautiful map. It does combine the 1970's a period of positive mass balance and the period since of negative balances. Thus, it does not show the mass balance loss that has driven the retreat as well, but we already have a graph that does that. So we just need to point that out wherever it goes. Greenland and Antarctica are not present and that is ok because we do not know the mass balance of either over this time period. Peltoms 12:39, 4 March 2006 (UTC)
BTW. The existing chart of "Global Glacier Mass Balance" is mis-labelled now, within the image. The title is "Glacier Glacier Mass Balance"... I wonder if Peltoms can re-export the chart with that title fixed. Lulu of the Lotus-Eaters 19:42, 4 March 2006 (UTC)
Several comments (maybe should have added them here)
I added several comments to the FAC page. Maybe I should have added them here, but I got to the article from Wikipedia:Featured article candidates. – Doug Bell talk•contrib 12:20, 4 March 2006 (UTC)
- Doug good comments. I looked at the FAC page and other than one person the comments are generally good and we have addressed most of these. This article is not about the impact of glacier retreat. The ozone hole has nothing to do with glacier retreat. The impact of the retreat on ocean species is not something that is realistic to have identified nor is the retreat of the ice sheets significant enough at this time to have caused a discernible change. In my opinion we should not expand on the impacts as they differ from watershed to watershed. Peltoms 12:54, 4 March 2006 (UTC)
- A number of errors are creeping in as we try to further summarize material. From the advancing glacier statement to the surging glaciers being the ones advancing in Alaska. Keep up the good work of these edits. I will go through the whole article to make sure it is correct this weekend, and let you worry about it sounding good.Peltoms 13:07, 4 March 2006 (UTC)
- In an effort to just offer a passing comment on some of the issues raise in the FAC nomination, I have added a bit to sea level rise and a few areas and done a major reorganization of the article structure. I am in the middle of working on it in my userspace and hope to conclude over the weekend, so I ask that any alterations be made to this article and not my update, unless you see something terribly amiss...my altered article is located here...User:MONGO/gr if anyone wants to have a look...as I said, it still has a few areas I am working on.--MONGO 13:08, 4 March 2006 (UTC)
- Just please try not to lose the clean-up I did to this article in the new version. Just to be clear, by "I ask that any alterations be made to this article" you are talking about Glacier retreat, correct? – Doug Bell talk•contrib 13:23, 4 March 2006 (UTC)
- You can edit anywhere you like, but prefer it here in the Glacier retreat article space...if someone can fit and correctly label the map we have been offered into this article, that will guide me on where to place it in the version I am working on. If anyone doesn't like my version, I can scrap it. I have yet to address all the concerns brought up by yourself of Mclean on this talk page above, for as I said, I am mainly attempting a reorganization after at least 4 editors said they didn't like the current structure. Those are excellent points you brought up at the FAC page.--MONGO 13:32, 4 March 2006 (UTC)
- No problems...I know when I moved the article to my userspace and I can update it all there from the diffs...just open two browsers.--MONGO 13:36, 4 March 2006 (UTC)
- User:MONGO/gr is now a dead link. I had added some useful passing comments about sea level rise and found references...but it was dumb of me to move the article off the main page and edit it independently, so I deleted my page. Before I did, I replaced this article with mine and then reverted back to the regular version.--MONGO 09:00, 5 March 2006 (UTC)
Graph of advancing glaciers in Alps
This graph seems to present information that doesn't really match the overall conclusion that I get from reading the article. Looking at this graph, the current number of advancing glaciers looks pretty similar to a stable period that occurred around 50 years ago. The article is comparing the numbers to a period that, at least for the period covered by the graph, does not look typical, and provides no comparison to the earlier period. This discrepency actually casts some doubt in my mind regarding the analysis in the article. – Doug Bell talk•contrib 23:13, 4 March 2006 (UTC)
- The graph needs to go back to about the year 12,000 BCE to be useful in my opinion. This article covers from about the year 1850 so it should at least go back beyond that, but 1850 was the end of the little ice age and it would be nice to see evidence from thousands of years ago, alas, that may be very tough to come by.--MONGO 10:06, 5 March 2006 (UTC)
- Of course I agree with MONGO that it would be great to have a chart going back to 12,000 BCE, or even one to 1850, for that matter. Unfortunately, we have the data we have. Obviously, if the experts could infer data from earlier using other techniques (core samples? striations?), it would be lovely to present them; but I have no idea whether that's possible.
- That said, I think the chart shows more than Doug Bell suggests. If the climate were really stable, relatively long-term, presumably the lines would stay around 50% as a constant. What we see in the chart is numbers quite a bit below 50% for the early part of the century, followed by a brief decade or two of majority expansion (but from the reduced sizes reached in 1970-ish), with more uniform reduction of glaciers in the present than in any previously directly measured period. I don't think the moral someone should get from the article is that glacier retreat is a brand new and unprecedented phenomenon; obviously ice ages have ended before, accompanied by much larger glacier retreat (by much larger glaciers) than we have now. Still, I think it probably adds up to less glacier mass right now than at any time in the last 14,000 years (the article doesn't directly say that, but it seems likely, I think). Clearly, that's not entirely a question of anthropogenic effects, which seems to be the hot-button; but those are still significant. Lulu of the Lotus-Eaters 19:33, 5 March 2006 (UTC)
- I'm not sure I see why you say that you would expect the lines to stay around 50%. I suppose it would help to see data that shows how many glaciers are stable (i.e. neither advancing nor retreating) and how many retreating, but assuming that some percentage of them are stable, I would think that a period of stable glacial mass balance would have somewhat less than 50% of the glaciers advancing—perhaps significantly less. That said, my comments were in regards to the overall conclusion I get from the article that the period since 1980 has been an exceptional period of retreat, yet the graph appears to show that the number of advancing glaciers today is not unusual. It's hard to tell from the data presented, but since this graph was included, and I'm not doing independent research on the subject, I'm left to wonder about the discrepency between the graph and the discussion.
- That's very, very ballpark, of course. But if global glacier mass were constant, I would expect there to be approximately 50% advancing glaciers and 50% retreating glaciers. In any given yearly cycle, each individual glacier either advances or retreats, though possibly by a small enough amount as to be unimportant. The caveats are obvious, of course, if one big glacier retreats a whole lot, that might add up to the same mass as ten little glaciers advancing a little. The fact that in something like 70 of the last 80 years, more glaciers have retreated than advanced is interesting, especially since those years with more advancing glaciers show only a modest tilt in that direction, while right now virtually every glacier is retreating (at least in the Alps, which this chart summarizes).
- You're right that in the Alps, at least, the period since 1980 isn't so much different from the 1940s. Still, continuing retreat represents reduction from already reduced sizes. I think the summary in the lead that the whole period since 1850 has been one of overall glacier retreat is the main thing to come away with (even though this specific chart doesn't go back that far). There's been some acceleration of that since 1980 (probably largely due to anthopogenic effects), but the general trend is 150 years. Or more broadly, a looser general trend is about 14k years, but with century-long fluctuations within that tendency. At least that's the impression I come away with from the article... as a non-climatologist. Lulu of the Lotus-Eaters 23:40, 5 March 2006 (UTC)
- I'm not sure I see why you say that you would expect the lines to stay around 50%. I suppose it would help to see data that shows how many glaciers are stable (i.e. neither advancing nor retreating) and how many retreating, but assuming that some percentage of them are stable, I would think that a period of stable glacial mass balance would have somewhat less than 50% of the glaciers advancing—perhaps significantly less. That said, my comments were in regards to the overall conclusion I get from the article that the period since 1980 has been an exceptional period of retreat, yet the graph appears to show that the number of advancing glaciers today is not unusual. It's hard to tell from the data presented, but since this graph was included, and I'm not doing independent research on the subject, I'm left to wonder about the discrepency between the graph and the discussion.
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- It would not surprise me if the glacial mass is at a low point. However, if the overall trend over the last 14,000 years has been lower (and that's certainly the impression I'm left with), then I don't know how surprising it should be if the mass is at an all-time low at this point. Neither do I know from reading this article what percentage of glaciers have been advancing vs. stable vs. retreating over this period, so I'm just looking for the supporting evidence for the conclusion in the article that the percentage advancing today is exceptionally low. The only point I was making is an issue with the presentation of data that didn't seem to match the explanation—I'm not trying to provide my own explanation or interpretation.
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- Nah... I didn't mean you Doug. But on this talk page, and on the FA nomination, the idea of tying glacier retreat to global warming—and specifically to anthropogenic causes of global warming—has come up a few times. I am opposed to belaboring that connection within the article. This article shouldn't be a defence of the Kyoto Treaty (even if I myself support it; as probably do most of the actual climatologist here). I do think there's some merit in describing some negative consequences to humans of glacier retreat, simply because it motivates interest in the article; but certainly not in alarmist or political terms (nor do I think the excellent summary of those effects that MONGO wrote is guilty of those pitfalls). Lulu of the Lotus-Eaters 23:40, 5 March 2006 (UTC)
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I think the article has been very neutral and we have stuck to the facts, including talking about currently advancing glaciers and noting right from the start that the last century has two periods of widespread retreat and one of modest advance. The graph shows this. The point you are missing Doug and that Lotus Eater is seeing is that the number of advancing glaciers in the Alps as of this year is at an all time low for the data record. I could add other mountain ranges to show same thing, but that would clutter image. Now realize that the glaciers are in a less advanced position now as well, so to trigger further retreat takes even greater warming. The retreat phase is unprecedented as noted by many alpine glaciologist and others around the world as noted in our article. As far as going back in time. We could do that, but I do not see the point. The Holocene glacier history is known well enough to show a general retreat of glaciers from 14,000 BP to 9000 BP. The glaciers were at minimum sizes most likely comparable today from 9000 to 5000 BP than the neoglacial began and there have been several advances and retreats. To go through the various cycles would be confusing and defuse the point from the focus which is the current retreat. The current retreat has exposed in Canada the Alps, and Cascades several key remains indicating that this is the least ice in those areas in many thousands of years and the retreat is increasing not ending at this moment. Thus, we are not at the conclusion of the retreat cycle. That is why this article is crucial now. Peltoms 00:31, 6 March 2006 (UTC)
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- Well, I did write above: continuing retreat represents reduction from already reduced sizes, which would seem to be an endorsement of Peltoms observation :-). But in any case, I'm clearly in agreement with Peltoms points (I better be: he's an actual expert). I think that Doug Bell has a point here, a lay reader might need a little more help in interpreting just what the graph is showing. Maybe a few words taken from the discussion in this section could be recruited? Lulu of the Lotus-Eaters 03:29, 6 March 2006 (UTC)
- I agree that the article is very neutral, and my comment above was applauding that. I can see where maybe my comment could be interpretted as implying that the article wasn't based on science or wasn't neutral, but that is not at all what was meant. I think the article is quite good overall. My comments here were those of a layperson (albeit reasonably well read in scientific topics) reading the article. I was not disputing that the glaciers are in rapid retreat, but merely pointing out that the description in the article related to this graph does not appear to make a balanced comparison to the past represented. I trust what you say above to be true, and am only bringing this up as an issue because of the appearance. – Doug Bell talk•contrib 01:04, 6 March 2006 (UTC)
superscript references
I think the superscript references are a great improvement! These are better than numbers, and now do not interfer with the text as they are easier to read past. In fact, I like it so much I just created a new template {{ref_harv}} to support this style so that every reference doesn't require <sup></sup>. – Doug Bell talk•contrib 00:08, 5 March 2006 (UTC)
- I found it hard to read pass the plain text references too. I think the superscript solution is clever and a big improvement. Walter Siegmund (talk) 04:50, 5 March 2006 (UTC)
- Gee, that is why my version was such a mess as I hadn't removed the superscript notations....is the new harv cite now lsited as an alternative for those who may also wish to use this new template in other articles? If so, where?--MONGO 09:02, 5 March 2006 (UTC)
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- Well, if you looked at the template talk page, you could have answered that question for yourself. :-) See Template talk:Ref and Wikipedia:Template messages/Sources of articles. – Doug Bell talk•contrib 09:59, 5 March 2006 (UTC)
- Thanks..saw it after I made my commment and was too lazy to update myself.--MONGO 10:03, 5 March 2006 (UTC)
- Well, if you looked at the template talk page, you could have answered that question for yourself. :-) See Template talk:Ref and Wikipedia:Template messages/Sources of articles. – Doug Bell talk•contrib 09:59, 5 March 2006 (UTC)
Reorganization
I have completely reorganized the page to eliminate the original outline I created when this thing got started. As can be observed, I broke glaciated areas down into Tropical, Mid latitude (with eastern and western hemisphere subsections for evenness) and Polar main sections rather than breaking it into continent and mountain chains. I added brief intros into each section that should be adequate. I have also attempted to address each major point brought up by several editors in the FAC process and on the discussion page of this article. My changes are not, of course written in stone, but I personally think it looks better this way. Some tweaking and word play is still needed, a through copyedit to examine missing commas and spelling errors would be good yet and, well, this article is still under construction. We still need to identify the surging glaciers in Patagonia as that was brought up and I haven't addressed it yet. It may be easiest to open two browers and compare the edit before I started this as shown here in this imbedded link with the version I now have completed with this edit. I also added a passing comment about sea level rise (which I think belongs elsewhere, but other commentors felt differently) and an appropriate citation.--MONGO 10:37, 6 March 2006 (UTC)
- Personally, I like the organization by lattitude much better than the organization by continent. Lulu of the Lotus-Eaters 21:47, 6 March 2006 (UTC)
- I added fairly extensive comments on the new organization and content to the FAC page. I added them there since some of the issues are the same as the previous comment I left on that page. – Doug Bell talk•contrib 22:00, 6 March 2006 (UTC)
- I saw that...left you a message on your talk page. I for one am not infavor of splitting it into a northern and southern hemisphere as this will create a huge inbalance of the sections...there simply aren't many mid latitude glaciers in the southern hemisphere. I addressed a number of issues that you had left previously but since I don't agree with all the issues you have, I am not going to address all of them.--MONGO 01:58, 7 March 2006 (UTC)
FAC nomination
I've noticed that the FAC nomination has grown rather complex; and since it was made, we've done quite a bit of reorganization (as well as smaller fixes)... some, but not all, in response to the FAC comments. I wonder if there's any appropriate way to "re-nominate" the article. Or maybe just put all the older FAC comments into an archive or subsection. I'm just thinking that it's a bit hard to tell now which issues have been addressed, which deliberately not addressed, which still problems, etc. I can sort of make my own judgements about those, but someone stumbling along the FAC, who hasn't seen the article history, will probably be bewildered. Lulu of the Lotus-Eaters 03:20, 7 March 2006 (UTC)
- Most of the issues that have been brought up by the commentators have now been addressed. I just looked over some of Doug Bell's advice and made some minor adjustments. The FAC process is supposed to be a helpful process that is engineered to help all the editors involved to "fix" the areas of weakness. From my standpoint, some FA items are just opinions, and not based on any set standard, but almost all of them have been excellent. The level of correction needed to address individualized concerns is also a matter of POV. I use them as a guide and do not necessarily do everything that is requested. As what happened with a previous article I worked on to get it to FA, the commentators actually made substantive edits that assisted me, and thankfully, this has happened here. I find that the best thing to do is if see something broke, then fix it...especially if all we are talking about are very minor alterations to sentence structure. The article is too unstable at present to be a FA...and stability is crucial for FA status. Let's give it a couple of weeks as I still have a few things to do of a minor note.--MONGO 03:35, 7 March 2006 (UTC)
I have gone through the entire article and can vouch that it is scientifically sound through and through. It reads very well I like the new organization. I also want to point out that I have never worked with such an editing team. You collectively bring an amazing attention to detail and an ability to clarify material, and to learn and assimilate material in an area that you are not experts in. I look forward to seeing what other changes will come. Is there any weakness scientifically in your mind? I will add a section on the Alaskan glacier tidewater cycle to the Taku Glacier article so that it does not take more space here.Peltoms 15:43, 7 March 2006 (UTC)
- That's very kind and I thank you. Lulu, Wsiegmund, yourself have added most of the scientific data which made the article. Excellent comments by editors mclean25, Doug Bell, WorldTraveller, Lupo and a few others also demonstrate the best of Wikipedia by their very through analysis of the weak points of the article. I believe that the majority of their comments have now been addressed. Doug Bell even created a new template for the citations that automagically make the citations superscript small within the article text, eliminating the need to tediously go to every citation and type <sup></sup>...that was a big help and makes it easier to edit this article. Bell also asked we explain Glacial Lake Outburst Flood (GLOF) and this may need to be made in a sub article, but a passing explanation needs to be addressed here. We have also been asked to briefly mention in more detail a few surging glaciers and the mechanisms behind that...and mention the few advancing glaciers such as in Patagonia (Perito Merino) I believe as one example. As spin offs from this, Glacier mass balance looks good and we could also work a lot more on Holocene glacial retreat as that was asked to be explained. I think a bit more tweaking to give the article better readablity between some areas that have a lot of facts and figures is needed, and slowly I think this is happening. In a couple of weeks, once we have all reached an agreement that the article is the best we can do, then I'll invite the previous commentators to look it over again, and we will renominate the article. I am however, in complete agreement with you...I would rather have it be a very good article with excellent references and facts and figures, than have it be a featured article in which we would lose any of this information. If anything, this longish article could even be expanded...no mention of Sierra Nevada glaciers is even made and that is an oversight...see this reference [19]. No mention of the glaciers in east Asia is found such as in Kamchatka. Aside from a few minor improvements and some grammar issues in a few points, I think we are pretty close.--MONGO 20:49, 7 March 2006 (UTC)
- While I concur with MONGO in thanking the wonderful work of Peltoms, Wseigmund, mcclean25, Doug Bell, WorldTraveller, Lupo (and also William M. Connolley; and anyone both of us may have forgotten), he gives me too much credit. I contributed to some wording and organization (and to the biggish reference project), but really can't claim any credit for the core scientific data provided by the experts. I tend to agree with MONGO that providing a depth of information is more important than whether it meets FA status per se; in either case we benefit from the FA nomination comments, and readability continues to improve. 23:29, 7 March 2006 (UTC)
- Give me and others a couple of days to make some tweaks and I'll ask al the commentators again how they feel now that a lot of their comments have been addressed.--MONGO 20:55, 7 March 2006 (UTC)
- I just created a stub article that can be expanded Glacial Lake Outburst Flood...it has a few links to get us started.--MONGO 21:29, 7 March 2006 (UTC)
- I find it hard to distinguish between GLOF and a Jokulhlaup. I did work on that page. We should definetly stay away from surging glacier mechanism discussion. It is neither simple, nor consistent nor completely identified in various cases. We have avoided using surging glaciers in our discussion of glaciers, since the dynamics would confuse the issue. Peltoms 17:04, 8 March 2006 (UTC)
- I think I kept surging glacier discussion out, may have made it look that way with the discussion about perito merino glacier...do you think we should also not detail a GLOF as much as I did or maybe move the discussion elsewhere? I'll be glad to do either if you think it distracts from the article.--MONGO 21:35, 8 March 2006 (UTC)
- I find it hard to distinguish between GLOF and a Jokulhlaup. I did work on that page. We should definetly stay away from surging glacier mechanism discussion. It is neither simple, nor consistent nor completely identified in various cases. We have avoided using surging glaciers in our discussion of glaciers, since the dynamics would confuse the issue. Peltoms 17:04, 8 March 2006 (UTC)
I think mentioning GLOF's is an important potential consequence of glacier retreat and deserves mention. Surging on the other hand is not. Peltoms 00:19, 9 March 2006 (UTC)
why?
Why doens't this article have a critiscms? or alternative viewpoints section like most other articles do?--205.188.116.66 23:13, 9 March 2006 (UTC)
- Can you be more specific? This article does not purport to show a viewpoint, but rather simply discuss current research, so it would be helpful if you could provide an example of what you mean. – Doug Bell talk•contrib 23:18, 9 March 2006 (UTC)
Well, you could try Michael Crichton for a very readable array of criticisms. Naturally his criticisms are themselves open to criticism, et cetera, but one thing they definitely do have in their favour is that they point out the religious-belief status of global warming and the problems with that. Have a look at http://www.crichton-official.com/speeches/index.html. Wikipedia would need harder scientific references than this, though. (Ryancolm)
- Criticism cruft. This article is about data. There is no alternative viewpoint. It mentions both retreat of glaciers and (the relatively fewer cases) where they are advancing. I don't understand what the alternative viewpoint would be. That they aren't retreating? Let's find the viewpoint before including it rather than assuming everything has to be rebutted. savidan(talk) (e@) 18:16, 18 April 2006 (UTC)
Some more comments
Hopefully this is the right place for these comments:
- The term "staking terminus location" needs to be defined.
- Working on these, slow but sure and will add to article text and will leave cites here to refer back to later when making corrections to article. Staking is used to measure movement and loss of thickness apparently.[20]--MONGO 03:26, 10 March 2006 (UTC)
- My suggestion is in the next thread below...a summary and maybe a new section here with a link to an expanded subarticle.--MONGO 10:36, 10 March 2006 (UTC)
- The term "surging" is used in the discussion of Alaskan glaciers without definition:
- "Even the surging glaciers are retreating."
- "There are many surging glaciers throughout Alaska whose terminal locations are due partially to climate and partially to surging behavior."
- I think our resident glaciologist did not want to go into a lot of detail on surging glaciers but I'll look for a brief cite that will explain the term. They apparently have nothing to do with warming or cooling but may be mistaken.--MONGO 03:26, 10 March 2006 (UTC)
- "Since 1912, the glacier cover on the summit of Kilimanjaro has apparently retreated 75%, and just from the period of 1984 to 1998, one section of the glacier atop the mountain receded 300 m (984 ft)."
It would be great if the percentage retreat represented by the 300 m figure could be provided to allow a relative comparison between the 75% and the 300 m. - "Since 1912, the glacier cover on the summit of Kilimanjaro has apparently retreated 75%" and two sentences later "Over the past century, the ice cap volume on Kilimanjaro has dropped by more than 80%." I think only one of these statements is needed, or perhaps since the first is talking about area and the second about volume they should be combined.
- I'll combine them and clarify.--MONGO 03:26, 10 March 2006 (UTC)
- "Early 20th century visitors to Chamonix, France remember the Bossons Glacier coming almost as far as the nearest roadway, but it has since lost 1,200 m (3,900 ft) of its length."
I'm not sure what the actual reference regarding this glacier says, so I was unsure how to rephrase it, but I don't think stating what visitors remember is the best phrasing. I suggest changing it to something like
"The Bossons Glacier in Chamonix, France has retreated 1,200 m (3,900 ft) since the early 20th century."
or if necessary for accuracy
"The Bossons Glacier in Chamonix, France has retreated 1,200 m (3,900 ft) from extents observed in the early 20th century."- Fixed now.--MONGO 04:20, 10 March 2006 (UTC)
- "As of 2005, 67% of the North Cascade glaciers observed are in disequilibrium and will not survive the continuation of the present climate."
This statement is saying two things, and I just want to make sure that's what is intended. It says that 67% of the North Cascade glaciers observed are in disequilibrium, and that all of the glaciers in disequilibrium will continue in disequilibrium until they melt away. In other words, no North Cascade glaciers in disequilibrium will stablize, but 33% of the North Cascade glaciers observed are not in disequilibrium.- Basically, we'll rephrase this, about 2/3 of the glaciers are in disequilibrium and are doomed. Though almost all the glaciers are in retreat, some will reestablish equilibrium once they reach a point where the gain/loss ratio is even.--MONGO 03:26, 10 March 2006 (UTC)
- "The 70 km (43 mile) long Fedchenko Glacier, which is the largest in Tajikistan, lost 1.4% of its length, or 1 km (0.6 mile), 2 km³ (2.61 yds³) of its mass, and the glaciated area was reduced by 11 km² (4.24 mile²) during the 1900s. Similarly, the neighboring Skogatch Glacier lost 8% of its total mass between the years 1969 and 1986."
I added the 1.4% for the length loss of the Fedchenko Glacier, but it would be nice have the % mass loss for this glacier to compare to the % mass loss provided from the Skogatch Glacier.- Will work on it, but was just utilizing the reference that we have and it seems to be one of the few relaiable ones that could be found off the web.--MONGO 04:20, 10 March 2006 (UTC)
- Icy Bay: need to identify where this is.
- The advance of Taku Glacier has averaged a rate of 17 m (55 ft) per year.
This needs to state the time period for this average.- Done, from the references, 1988-2005--MONGO 08:35, 10 March 2006 (UTC)
- "Jakobshavns Isbrae in west Greenland, a major outlet glacier of the Greenland Ice Sheet, is the fastest moving glacier in the world. It had been moving continuously at speeds of over 24 m (78 ft) per day with a stable terminus since at least since the year 1950." and later in the same paragraph, "Portions of the main trunk of Kangerdlugssuaq that were flowing at 15 m (49 ft) per day from 1988 to 2001, were measured to be flowing at 40 m (131 ft) per day in the summer of 2005."
Seems to contradict the claim of Jakobshavns Isbrae being the faster moving glacier in the world.- Reworded this section so as to make the understanding that the latter is a record of just one summer, while the former is over a period of 50 years.--MONGO 04:41, 10 March 2006 (UTC)
- "There are 32 glaciers that were measured to have have advanced, however these glaciers showed only a modest advance averaging 300 meters (984 ft) per glacier, which is miniscule compared to the massive retreat observed."
Given the characterizations of the advances as "modest" and "miniscule" and the characterization of the retreat as "massive" it would be useful to include the average retreat per glacier to support the comparison.
– Doug Bell talk•contrib 15:18, 9 March 2006 (UTC)
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- Done...added a reference as well.--MONGO 08:22, 10 March 2006 (UTC)
One more comment:
- "Also of great importance is the recent substantial retreat and acceleration since 1995 of a number of key outlet glaciers of the Greenland and West Antarctica ice sheets that may foreshadow a rise in sea level."
It's not clear what 'acceleration' is referring to. It could be acceleration of flow rate, or acceleration of rate of retreat. – Doug Bell talk•contrib 02:45, 10 March 2006 (UTC)- I'll have to defer that one to Peltoms as I really am not sure how to reword it.--MONGO 08:56, 10 March 2006 (UTC)
It is both velocity and retreat rate but velocity in particular. With these large floating ice tongues retreat is not as good a measure over short time periodsPeltoms 13:22, 10 March 2006 (UTC)
Proposed addition
I propose a brief summary of this and a new subarticle and hope Peltoms will chime in with his thoughts and of course corrections. I have provided one link for the information but hopefully we can find more...
Photography is one of the easiest methods to visually demonstrate the retreat of glaciers. With the earliest images of glaciers dating from the mid 19th-century, visual evidence of glacial changes have been documented on certain glaciers over a long period of time. Photographs of glaciers in the Alps and North American dating before 1890 and compared to photographs taken 100 years later, repeatedly demonstrate the retreat of glaciers. More recent photographs from the mid 20th-century from such locations as the Himalayas and compared to photographs taken since 2000, provide a reliable reference on the issue of glacier retreat. Modern photographic techniques such as repeat photography can be done from the ground, from aircraft and from space.
The earlier methods of simply measuring the length and width of a glacier, are now complemented by advances in techniques and technology. *This ablation section is mass balance not terminus change that is why it was removed.Peltoms 13:27, 10 March 2006 (UTC) Using another technique known as aerial mapping, large areas of glaciated regions can be examined from aircraft. Repeating aerial mapping surveys over identical glaciers over time allows glaciologists to photograph and map large areas. Global positioning mapping permits precise measurements of the area of a glacier to be measured. Laser altimetry is a method employed both on the ground and from aircraft. Flying over a glacier at a fixed altitude and route, laser measurements are made which determine the altitude of a glacier. Changes in altitude over time is recorded as alterations to the glacier thickness. Satellite imagery is employed to measure large glaciated regions and repeated frequently to measure alterations. --MONGO 10:31, 10 March 2006 (UTC)
- The ice radar is also not used for terminus work-there is alot of technology used on glaciers and most is not for terminus measurement which is the simplest-thus I would steer clear.Peltoms 13:27, 10 March 2006 (UTC)[22]
- What about just expanding the Glaciology article, instead of the more narrow subject of how the advance and retreat of glaciers is measured? It could talk about all the different technologies employed and the goals of the research. – Doug Bell talk•contrib 18:00, 10 March 2006 (UTC)
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- I can agree with that...this article is long enough anyway. A subarticle discussing the methodology used to measure glacier retreat might not be a bad idea also. What this article still needs is a bit more prose in between all the facts and figures, but I'm taking abreak from this article for about a week until I come up with some new ideas.--MONGO 06:09, 14 March 2006 (UTC)
Need footnote and citations
I am taking a look at this article, which a quick scan through looks quite good. However, I noticed one sentence in the "Glacier mass balance impact on terminus behavior" section that could use a footnote with some citations, to mention what/where some of these glaciers are:
- "There are current advancing glaciers, but all are advancing at modest rates, suggesting that they are not far from equilibrium."
Also, it could be reworded, to something such as:
- "Currently, there are some advancing glaciers, all of which are advancing at modest rates. This suggests that they are not far from equilibrium."
The word *all* might be problematic too. Are you sure that they *all* are advancing at modest rates? This probably needs to be cited, especially if using the word *all*. Also, can you quantify what you mean by modest rates? -Aude (talk | contribs) 15:37, 24 March 2006 (UTC)
- Thanks. I think it may be off of one of the cites in vicinity to that sentence...but I'll check it out tonight. I believe what is trying to be stated there is that of the glaciers are that are advancing, all of them are doing so only moderately, indicating they are nearing equilibrium. Yes, we need to qualify what a moderate rate is as well. Thanks for the comments and don't hesitate to correct whatever you think needs fixing...I saw that Walter corrected some outrageous typos I made from a few hours ago.--MONGO 16:22, 24 March 2006 (UTC)
- I'm not quite accustomed to the referencing format in the article, but I found an article that discusses Hubbard Glacier advancing:
- Trabant, D.C., R.S. March, and D.S. Thomas (2003, January). Hubbard Glacier, Alaska: Growing and Advancing in Spite of Global Climate Change and the 1986 and 2002 Russell Lake Outburst Floods. Fact Sheet 001—03. USGS.
- This reference might be helpful to backup the sentence about advancing glaciers. -Aude (talk | contribs) 04:11, 30 March 2006 (UTC)
- I'm not quite accustomed to the referencing format in the article, but I found an article that discusses Hubbard Glacier advancing:
The name of the article
I saw this article was up at FAC. I supported it, but said that I had one concern: this is not an article about glacial retreat. It is an article about "glacial retreat over the last 150 years". Glacial retreat is different; it is conceptual, and there have been many examples of glacial retreat (and indeed glacial advance) throughout geological time, although obviously the ones in the holocene are the best known. A new article, detailing the mechanisms, processes and some examples of glacial retreat ought to be created at Glacier retreat (or as a redirect to Glacial retreat); this article should be moved to (something like) "Post-Industrial Revolution glacier rereat". What do others think? Batmanand | Talk 12:43, 29 March 2006 (UTC)
- I'll try and locate the thread that discusses the title. Peltoms is the "resident" glaciologist that worked on this article a lot. He defined "Glacial retreat" as the end of the ice ages...in other words, essentially the period also know as the Holocene glacial retreat. This article discusses Glaciers...as in more isolated smaller masses of glaciers that are not even necessarily remnants of the last ice ages, as many of the glaciers now retreating actually developed during the Little Ice Age. It doesn't actually fit into a Post-Industrial period as that is still ongoing and the industrial age only really just started at about the same time as the end of the little ice age...in other words, (I am not sure on this) there isn't much dtat to support evidence that the coal buring that became big in the early to mid 18th century actually hastened the retreat of glaciers...Glacier retreat is the term used by glaciologists for the period since 1850, generally. I orginally had the article titled as Glacial recession...but I agreed to change it as the other major contributors correctly commented that this is incorrect since we do not discuss the period that that tile would need to incorpoarte in text...the holocene period from 12 thousand until maybe 3 thousand years ago. We did spinoff Glacier mass balance Glacial Lake Outburst Flood and Holocene glacial retreat, all created as byproducts of this effort, with the latter in a riugh state but correctly titled to discuss other periods. See also small stub Pinedale glaciation. I appreciate your imput and let me know if I can clarify this any more for you.--MONGO 13:02, 29 March 2006 (UTC)
- That previous thread about the title is here in case you'd like a read of the discussion then.--MONGO 13:04, 29 March 2006 (UTC)
- My concern was that this article is time-set in that it talks solely about post-1850 glacial retreat, not about glacial retreat as a concept. I know that "Post Industrial Revolution Glacial Retreat" is not ideal; how about "Post-1850 glacial retreat" or something like that? It is the time-specific nature of the article that worries me, not whether it is called "Glacial retreat" or "Glacier retreat" or whatever, which was the subject of the poll in the archive that you linked me to (thanks for that btw). Batmanand | Talk 13:31, 29 March 2006 (UTC)
- I am not personally against an article title change. Again...we don't discuss Glacial as this is a different issue, we discuss the retreat of Glaciers. Glacial is a process...I recognize you don't have all the time in the world for this, but you should check out the link I provided above and read from there through a few other threads after that which explain why the title is what it is. I can also ask that we both see if Peltoms or a few of the other contributors chime in...again, a title change is not out of the question, but there would be numerous double redirects caused by this and I don't think the titles of things such as Post 1850 glacial retreat will be an oft googled query for information that this article provides...I'm not tryng to be obtuse, just trying to explain that Glacial means a lot of things whereby Glaciers is about just that...glaciers. I hope Peltoms can clarify this and I'll email him to let him know we are discussing this issue.--MONGO 13:44, 29 March 2006 (UTC)
- That sounds fine. The input of relevant editors would be more than welcome. Just to clarify: I am sure there are very good reasons for calling it "Glacier retreat" as opposed to "Glacial retreat". I am just asking if anyone minds moving the article to a name that better reflects how time-specific this article is right now. Batmanand | Talk 14:39, 29 March 2006 (UTC)
- I am not personally against an article title change. Again...we don't discuss Glacial as this is a different issue, we discuss the retreat of Glaciers. Glacial is a process...I recognize you don't have all the time in the world for this, but you should check out the link I provided above and read from there through a few other threads after that which explain why the title is what it is. I can also ask that we both see if Peltoms or a few of the other contributors chime in...again, a title change is not out of the question, but there would be numerous double redirects caused by this and I don't think the titles of things such as Post 1850 glacial retreat will be an oft googled query for information that this article provides...I'm not tryng to be obtuse, just trying to explain that Glacial means a lot of things whereby Glaciers is about just that...glaciers. I hope Peltoms can clarify this and I'll email him to let him know we are discussing this issue.--MONGO 13:44, 29 March 2006 (UTC)
- My concern was that this article is time-set in that it talks solely about post-1850 glacial retreat, not about glacial retreat as a concept. I know that "Post Industrial Revolution Glacial Retreat" is not ideal; how about "Post-1850 glacial retreat" or something like that? It is the time-specific nature of the article that worries me, not whether it is called "Glacial retreat" or "Glacier retreat" or whatever, which was the subject of the poll in the archive that you linked me to (thanks for that btw). Batmanand | Talk 13:31, 29 March 2006 (UTC)
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- What about making "Glacier retreat" a disambiguation page that links to "Glacier retreat since 1850", and also to "Holocene glacier retreat", "Glacier mass balance" and maybe a few other related articles? Lulu of the Lotus-Eaters 20:30, 29 March 2006 (UTC)
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- My edit a few days ago had similar concerns in mind. The Little Ice Age was cool relative to present, but was *little* and there have been much colder periods, for example when the Laurentide ice sheet covered major portions of North America. It also would be helpful to have a separate article on glacial recession, as opposed to glacier advance or glacial advance, that discusses the processes and mechanisms of glacier retreat. -Aude (talk | contribs) 20:49, 29 March 2006 (UTC)
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- Another distinction that can be made is between glacier retreat and ice sheet retreat (e.g. retreat of the Laurentide ice sheet).-Aude (talk | contribs) 20:58, 29 March 2006 (UTC)
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Ice sheets are glaciers on a larger scale. The vast majority of this article discusses individual glaciers as even the ice sheet of Greenland is only affected on it's outflow glaciers for the most part. If anything, Lulu has a decent suggestion, but I might as well withdraw the nomination until the title is stabilized.--MONGO 21:22, 29 March 2006 (UTC)
Uh, the current name "The Retreat of Glaciers Since 1850" doesn't meet the naming standards. It should be "Retreat of glaciers since 1850". See WP:NAME. —Doug Bell talk•contrib 02:49, 30 March 2006 (UTC)
- Doug Bell is quite correct here. The capitalization is definitely wrong. Not sure about the lead article, but I think it probably sounds better as Doug suggests, without the "The". Lulu of the Lotus-Eaters 02:54, 30 March 2006 (UTC)
- Omitting the lead article is point number 1.9 in the naming convention and is discussed in detail at Wikipedia:Naming conventions (definite and indefinite articles at beginning of name). —Doug Bell talk•contrib 07:41, 1 April 2006 (UTC)
- Thanks for being bold and implementing my suggestion. Batmanand | Talk 06:31, 30 March 2006 (UTC)
Glacier surging
I just added {{citeneeded}} to the first paragraph in Glacier_retreat#Western_hemisphere, where it states "Even the surging glaciers are retreating." I flagged this not so much that a citation is needed (though would be nice), but I'm not sure what you mean or imply here with that statement. I just found a recently created article on glacier surging which needs expansion. It's important to note that glacier surging is a process, largely independent of climatic influences, and that it is cyclical. Glaciers that exhibit surging behavior will go through a surging phase, will then experience a quiescent phase where they retreat substantially (the surge puts them out of equilibrium/balance) to return towards equilibrium. For surging glaciers in Alaska (Bering Glacier, for example [23] has experienced six surges in the past century), they go through the cycle on a fairly rapid timescale (geologically speaking). For surging glaciers in Svalbard and the Canadian Arctic islands, the cycle is much more drawn out over hundreds of years (due to the much lower amounts of precipitation). Thus, some glaciers in these regions may be undergoing major retreat currently, but the cause could be much more nuanced and be due to a combination of factors (mostly surging, but also climate). Thus, where it says "Even the surging glaciers are retreating.", it makes no sense to me. Surging (surge-type) glaciers do retreat (for reasons totally independent of climatic factors), in between the surge events. -Aude (talk | contribs) 21:22, 29 March 2006 (UTC)
- I was a bit apprehensive to work on this as Peltoms had mentioned that we shouldn't go into a lot of detail about the surging aspects of glaciers. I added a brief couple of sentences in the alaska section of the article if you care to have a look and let me know what you think.--MONGO 10:23, 1 April 2006 (UTC)
The point is true that surging glaciers have advance and retreat phases, the former shorter than the latter, but you can look beyond the phases for the trend, and what we see is surging glaciers retreating overall with the cycle imposed upon this retreat. It is not as straightforward which is why I suggested we avoid it. The same goes for large tidewater glaciers in Alaska, we mention several that are advancing, but this is the result of long term dynamic changes that I have explained at the Taku Glacier article.Peltoms 12:29, 2 April 2006 (UTC)
Bullets in refs
An editor recently added them. Contrary to his/her edit comment, I think the references look worse with the bullets. Maybe I just like the look of traditional academic articles, which wouldn't use that typography. But they feel like a gratuitous element to me... especially since the reference name is itself bolded and superscripted, given a good visual guide to where each one starts. Then again, I generally think too many WP articles use bullets too often. On the other hand, this is certainly not something to edit war over. Any other opinions? Lulu of the Lotus-Eaters 22:40, 31 March 2006 (UTC)
- I guess I am indifferent...either looks fine, although by bulleting the cited references it maintains congruity with the general references and the additional reading section...but those two sections probably should have bullets since they are listed in a different style(?).--MONGO 02:05, 1 April 2006 (UTC)
Some comments
The article is really tight now, much harder to find nits in it now. ;-) However, I did find a few, and made a few small copy edit corrections in the process (these are up to the "Polar regions" section, I'll review the rest later today):
- In the intro it states "The recent substantial retreat and acceleration since 1995 of a number of key outlet glaciers...". I know I mentioned this before, but I still don't find it to be clear what 'acceleration' is refering to. It seems to mean the acceleration of the flow of the glacier, but it could also mean the acceleration of the rate of retreat. I would attempt to reword it, except that I'm still not clear on which it is.
- In the "Glacier mass balance impact on terminus behavior" section it states "...it is in disequilibrium with the climate and will melt away without a colder climate." I suppose I could have been bold, because I believe that the correct statement is: "...it is in disequilibrium with the climate and will melt away without a colder climate or an increase in accumulation." However, that wording didn't sound terrific. Perhaps better is "...or an increase in snowfall." or "...or an increase in frozen precipitation." For now I left it alone and just commented here.
- In the "Western hemisphere" section it has the sentence: "The advance of Taku Glacier averaged a retreat rate of 17 m (55 ft) per year between 1988 and 2005." I'm pretty sure this should instead say "The advance of Taku Glacier averaged 17 m (55 ft) per year between 1988 and 2005." However, this seemed to be such an obvious misstatement given all the review this article has had that I had to wonder if I'm just misinterpreting it.
—Doug Bell talk•contrib 23:30, 31 March 2006 (UTC)
- I believe I adjusted the three points you made here...I am also looking at this recent work which discusses the increase in interior precipitation in the inland sections of Greenland and the acceleration of outflow glaciers...not sure where I am going to put that in the article, though.--MONGO 02:51, 1 April 2006 (UTC)
I only found one more comment from the "Polar regions" section to the end of the article:
- In the "Polar regions" section it states "The most dramatic example of glacial retreat...". Given the extended discussion on the naming of the article, I just wanted to make sure that "glacial retreat" is intended here instead of "glacier retreat".
This certainly gets my support for a FAC now. Previously, I was able to find at least a dozen issues on each pass through the article, most of them more significant that any of the four I found on this pass.
—Doug Bell talk•contrib 07:09, 1 April 2006 (UTC)
- The current name of the article is not a positive step for the audience finding this article via google etc. The key words are Glacier Retreat, to put a time frame on it we should say Recent Glacier Retreat, naming wise maybe Glacier Retreat with global warming, we are very focussed on the recent and to a less extent since 1850. The article is quite comprehensive for the present and only moderately so for the last 150 years. In terms of the ice dynamics in Greenland, we talk about the acceleration already which is related to terminus behavior. The increase in snowfall is not related to glacier terminus behavior at this point.Peltoms 12:21, 2 April 2006 (UTC)
As to the Taku Glacier, Doug is correct. I suspect someone slipped the retreat in figuring it was missing. However, since this is one of the glaciers I work on and have published terminus changes for the glacier, I can attest it is advancing. Albeit the rate of advance has diminished of late for the first time in over a century. This is explained on the Taku Glacier page.Peltoms 12:25, 2 April 2006 (UTC)
I'll make the corrects you both mention and have asked Peltoms what the best google queried words to link to this article may be...I can create a redirect page that will link any gogle query, be it glacier retreat, recent retreat of glaciers, etc...and it will bring them right here.--MONGO 17:48, 2 April 2006 (UTC)
Kilimanjaro
For a school project I once had on the retreat of glaciers in Africa, I uploaded two images of Kilimanjaro; one from 1993, and one from 2000. They show the rapid retreat of the glaciers, and I think this article would benefit from them. Jon Harald Søby 07:38, 4 April 2006 (UTC)
- These are images of snow cover on Kilimanjaro. The glaciers, which occur only at summit, are not appreciably resolved in either image. Dragons flight 11:58, 4 April 2006 (UTC)
- Yes, I saw these images and I think I uploaded them to commons. I had them on the page mistakenly and by accident also thinking that they demostrated glacier retreat, when in fact the show the changes in snow cover from one year to the next. But even so, the images are both from the month of February and so show a dramatic change over 7 years, or at least they compare one year that had a lot of snow with one that didn't.--MONGO 12:52, 4 April 2006 (UTC)
- I didn't know they were already uploaded so I'll have to get to commons and ask that mine that I uploaded be deleted.--MONGO 12:55, 4 April 2006 (UTC)
- Nice pictures but I agree with Dragonsflight they showing nothing other than a change in snowcover albeit large and partly due to glacier retreat between two February'sPeltoms 12:53, 5 April 2006 (UTC)
Beefart offers a personal observation: I was a member of an expedition to Kilimanjaro mounted by the University of Cape Town Mountain and Ski Club in about 1972. We spent a week at the summit and climbed most of the important glaciers. Some of the walls of ice we climbed at that time simply do not exist today. I have photographs of the team at the summit of Kili, clearly showing walls of ice three or four metres high in the near background (10 to 20m distant). Today no such walls of ice are to be seen within a bull's roar of the summit.... 203.57.208.94 12:44, 18 April 2006 (UTC)
- If you have images you would like to allow Wikipedia to use and don't know how to upload them, contact me on my usertalk [24]. Any images of glacier changes in Kilimanjaro would be most welcome.--MONGO 13:00, 18 April 2006 (UTC)
Missing perspective: current period of retreat in an historical context?
Hi everyone, first off let me congratulate you for the excellent article, and all of the hard work that is obvious in reading it. For a climate change neophyte, this was very informative stuff.
However I can't help but think that a key perspective that is missing here is this: how does the current period of retreat (1850 - present) fit into the overall climate history of the planet? Other than a passing mention of the Little Ice Age (1550 - 1850), there is no discussion of what I'm guessing is a long history of dramatic glacial change, with periods of both advance and retreat.
I'd like to know more about that history. How much do we know about the overall glacial cycle? What are the primary reasons for changes from advance to retreat, and vice versa? Have there been any significant periods of equilibrium, and what caused that to happen? And what are some of the various views about where this current period of retreat might fall within the overall cycle? I would think the potential implications of the answers to those questions would be profound, and would be particularly noteworthy given the global warming controversy.
Just my two cents. --Gordon Jones 05:15, 18 April 2006 (UTC)
- This article addresses only the time period of 1850 and later. I draws no conclusions from previous periods and is essentially a "current events" topic (geologically speaking). We deliberately did not discuss global warming as that is an area unto itself. Essentially, the glaciers today are at close to an all time ebb from the end of the last ice age.--MONGO 09:33, 18 April 2006 (UTC)
References format
Remember, nobody owns any particular article. Cite.php references are demonstrably better than the old, deprecated reference styles like {{ref}} and {{ref harv}}. In addition, this is the only article I've ever seen formatted like this, which is bad from a user viewpoint because it isn't consistent. --Cyde Weys 09:58, 18 April 2006 (UTC)
- NO and you certainly don't either...but of course...unilaterally, you alter the harvard style that was worked on by others. It passed easily through FA votes...where was this style that you say was better voted on? I never saw a vote. Who determined that your style is better? I expect to know how this can't be viewed as a unilateral and overly bold action on your part...and now you even reverted back. Explain yourself.--MONGO 10:06, 18 April 2006 (UTC)
- I got news for you...this style you think is "better" [25] is awful in the editing window...it takes up too much space in the text of the article as compared to this. Who decided to do these "updates" to the references style...where was this voted on?--MONGO 10:10, 18 April 2006 (UTC)
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- Clyde is plainly and wholly wrong here. Harvard referencing is not deprecated; there are advantages and disadvantages of harvard vs. m:cite.php, that largely depend on the specific subject area and article organization. All of the principal authors of this article discussed this (all of us quite aware of the option of m:cite.php), and came to the conclusion that Harvard was the best choice here. Moreover, we spent a whole lot of work doing the references. A strong consensus was reached.
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- Of course this doesn't mean that we own the article, nor that a decision that was made will never change. But what it does mean is that any change to reference style needs a good and thorough discussion on the talk page before any change is made, and proof that a different consensus now exists. Lulu of the Lotus-Eaters 16:02, 18 April 2006 (UTC)
First of all, FA really has nothing to do with references styles. And of course I can alter anything that was worked on by others, this is Wikipedia, the free encyclopedia that anyone can edit. Here's a quote that's on every edit page: If you don't want your writing to be edited mercilessly or redistributed by others, do not submit it. And this action is far from unilateral, we've been working on cleaning up references for several weeks now. And this style is demonstrably better. It actually decreases the overall article length by a bit and solves the problems of mismatched refs, orphaned refs or notes, out of order refs and notes, etc. And adding a reference is now as simple as adding it inline with the article text; you don't have to edit two places to add a reference. Cite.php is the wave of the future. It wasn't really ever "voted on" — the older reference templates simply became deprecated when it was unveiled. --Cyde Weys 10:14, 18 April 2006 (UTC)
- I'm not sure how to respond to this. Okay, I'll be my usual blunt self....substantive changes are usually discussed first....assume that some did not know that this "wave of the future" had happened...and please do explain how "Cite.php is demonstrably better"...for I seem to miss how the editing window is more manageable when much of it is taken up by reference within the article text. The harvard style was perferred by most that worked on this article as it is alphabetical.--MONGO 10:37, 18 April 2006 (UTC)
It passed easily through FA votes... that's great, but it's meaningless. The article still looks the same from the outside with either format. Anything that can be done with the idiosyncratic metatemplate-based citation methods can be done using the <ref> tags with less maintenance and at a lesser server expense. This could end up at WP:LAME. — Apr. 18, '06 [10:15] <freakofnurxture|talk>
- No, it's not meaningless...unless you are here to do something other than write an ecyclopedia--MONGO 10:37, 18 April 2006 (UTC)
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- I agree that the FA status of the article is not really relevant to the style of citations. Peer reviewers usually look at the quality of the cites, not the referencing style. However, I disagree with the statement that the "The article still looks the same from the outside with either format.". One style ( cite.php ) gives numbered citations that are ordered by their first appearance in the text. The other (harvard) gives named citations and orders them alphabetically.
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- Personally, I agree with Cydes argument that the being consistent is important. On the other hand I can see one advantage of the citations the way they are currently set up. Seeing a citation such as an author name or BBC helps one know the type of citation to expect. Those familiar with the topic will recognise the authors name and may well know (or guess) the source being referenced. When I read papers seeing the name is often enough to know which paper is being cited. However, wikipedia is aimed at non experts so I think this advantage is probably quite moot in given that audience. With respect to the references being listed alphabetically, I see no advantage for this format over a numerical ordering. Each reference is hyperlinked so to find the references is easy whether going from references to text or the other way. The advantages of an alphabetical listing are primarily for a paper only article. Consequently, this should only be of concern if we envisage that users will be printing these articles to read later. They may well be doing this, especially if they are of FA quality and can be used in a school class.
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- With respect to the editing window, I feel it is better for an editor to see the content of the reference while editing the text rather than having to scroll down to the bottom. This is especially important when editing a 'section' of an article as it is not possible to scroll to the references in such a mode. While I agree the readability is not great in the editing window its advantages (context) out weight this problem. Plus, the preview option allows for readability.
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- Thanks Daycd for discussing this. Your points are very reasonable. As I say above (or maybe on Clyde's talk page), changing consensus is quite conceivable, it's just acting unilaterally that is bad manners (especially given the large amount of work earlier editors have done, and the fact we previously discussed and reached consensus on the exact issue).
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- As to alphabetical: Don't you ever print off a a good WP article to read on the train, in the path, or to give to people as photocopy? I do those things, and in that context, hyperlinks aren't so useful. OTOH, alphabetical citations are really great for that. Moreover, while I'm not in the same ballpark as an expert in this topic (even though it piqued my interest, and I am a major editor), I am expert in some other areas. If I read something in my area, an inline reference to a particular author name gives me a pretty good sense of what that citation is about. Seeing: Some argue Foos are Bars.(Butler) tells me a lot. Seeing Some argue Foos are Bazes.[27] tells me much less (until I flip through the pages, or scroll down to the note).
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- I think m:cite.php is absolutely the bees knees for genuine footnotes. That is, notes that actually contain discussion of the concept outside the mainflow, and may or may not also include citation references. For that, the natural order really is the same as the order the article flows in. m:cite.php still has some issues when you used named references, but rearrange content: the full annotation that had occurred first might now be non-first. That's a hassle, and not entirely painless to track down in a long article. But overall, for footnotes per se, m:cite.php is the best choice.
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- What we have in this article is not really footnotes though. It's citations. That's a somewhat different concept. Yes, we use a particular reference to support a particular statement in the body text, but the references taken as a whole are also a sort of bibliography for the article. And we include little or no editorial annotation of the provided citations, just the citation details. For that, Harvard works out better. In fact, being old fashioned, I was never all that excited about superscripting them as opposed to simple parentheses; but that's just typography (and moreover, I happily bowed to the consensus that disagreed with me). Lulu of the Lotus-Eaters 17:25, 18 April 2006 (UTC)
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Using cite.php makes the encyclopedia better by making referencing easier and standardized. 24.91.16.229 11:13, 18 April 2006 (UTC)
- I understand uniformity and the server lag issue...this article was preferred rto be in the Harvard style due to the scientific nature of the artical. We believed that the references in an alphabetical senquence at the end was more professional looking. We did harvard referencing after first using ref|note style for these reasons.--MONGO 11:46, 18 April 2006 (UTC)
Thanks
Hey, guys, thanks for bailing me out. I was reverting a long string of vandalism and I also, without noticing it, reverted across some vandal's deletion. The upshot of this was that I lost a whole pile of stuff. Whilst trying to fix the huge mess I'd made, other editors rushed right in and fixed it up before I could shake a stick at it. This is a very well-maintained page by the look of your speed and accuracy. Thanks again and keep up the good work. — Dave 14:47, 18 April 2006 (UTC)