View source for Talk:Noctilucent cloud

{{merged-from|Polar mesospheric clouds|19 December 2021}}
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==A note==
I added a link to a photograph of NLCs from Punta Arenas, maybe the only one image of a southern NLC taken from ground available on the net (also it's my first contribution to wikipedia :) -- nherm
*Thanks, Nherm, and welcome to Wikipedia. You should think about creating a userpage for yourself. I hope to see more contributions! [[User:Denni|Denni]][[User_talk:Denni|<span style="color:#228822;">&#9775;</span>]] 02:53, 2005 August 10 (UTC)

== Influence of Spaceflight ==
It is mentioned in the main article that Manned Spaceflight is a contributing factor to the appearance of NLCs. Can someone please provide a reference for this conjecture? It is my understanding that at 82km altitude the intense UV-radiation from the sun dissociates water molecules very quickly. With half-life times of mere hours, its a little curious how these can be a contributing factor. [[User:Albester|Albester]] 18:14, 18 May 2006 (UTC)

Not sure how to indent a reply here (and the main article isn't editable by AC like me), but it looks like shuttle exhaust is more closely related to PMC/PMSE:

Stevens, M.H. et al., Antarctic mesospheric clouds formed from Space Shuttle exhaust, <i>Geo. Res. Lett.</i>, <b>32</b>, 2005.

Are you sure that the half-life is "mere hours" at the mesopause? The clouds are an almost permanent fixture in the polar summer, so I have a hard time believing that there's that much water being transported to that altitude. Also, here's a citation for the anthropogenic change "attribution needed":

Thomas, G., Are Noctilucent Clouds Harbingers of Global Change in the Middle Atmosphere?, <i>Adv. Spc. Res.</i>, <b>32</b>, 1737&ndash;1746, 2003.  <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/69.91.134.125|69.91.134.125]] ([[User talk:69.91.134.125|talk]]) 19:16, 8 November 2007 (UTC)</small><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->

Noctilucent Clouds in Popular Culture:

Also title of a song by [[Jim Cole]] and title of song by [[The Chromatics]]

== Padmasambhava ==
This is pure nonsense but I believe that noctilucent clouds are physical manifestations of planetary wisdom (composed of frozen mist, illuminating the night, closest to empty space, poorly understood, and able to subsist at altitudes other clouds can't cut it at.  Keep up the good work brothers!
--[[Special:Contributions/68.56.0.116|68.56.0.116]] ([[User talk:68.56.0.116|talk]]) 14:44, 11 December 2007 (UTC)

== When & where ==

Does anybody know at which time of day, relative to sunset/sunrise, can noctilucent clouds be seen and on which latitudes? It would be nice to have graph displaying this in the article. --[[Special:Contributions/83.131.82.102|83.131.82.102]] ([[User talk:83.131.82.102|talk]]) 11:38, 9 March 2008 (UTC)

I don't know if any of this might help http://www.netweather.tv/forum/index.php?showtopic=46972  <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/92.21.136.202|92.21.136.202]] ([[User talk:92.21.136.202|talk]]) 19:55, 18 June 2009 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->
also 
http://spaceweather.com/archive.php?view=1&day=18&month=06&year=2009

== What the article needs for GA ==
*Convert templates for all units (mi to km, C to F)
*Either the creation of new articles where there are red wikilinks, or their removal
*Nbsps between numbers and their noun
That's the short list.  [[User:Thegreatdr|Thegreatdr]] ([[User talk:Thegreatdr|talk]]) 17:18, 7 October 2008 (UTC)
:Wow, great job on the article, Reyk!  This one could be on the fast track to [[WP:FA]]!  One minor quibble with Thegreatdr, redlinks are a good thing, not a bad thing.  While it would be ideal for someone to make them into articles, they should not be removed if an article could be created in the future, they should be kept.  It is not a GA, or even an FA, disqualifier.
::Thanks. I think the only red link remaining is the one for [[Otto Jesse]]; I'd start an article on him myslef beause he seems a notable person, but I can't find anything about him besides what's already in this atricle. Aside from that, all of Thegreatdr's suggestion have been taken care of, and I believe the [[Wikipedia:What_is_a_good_article%3F|good article criteria]] are met, so I'm off to nominate it now. I think it's still miles away from FA standard and probably not the kind of topic that ''becomes'' an FA anyway, but thanks for saying so. Thank you both for your help. [[User:Reyk|<span style="color:maroon;">'''Reyk'''</span>]] [[User talk:Reyk|'''<sub style="color:blue;">YO!</sub>''']] 01:23, 9 October 2008 (UTC)
:::See [[spoo]] (a former featured article).  NOTHING is too obscure for FA :) -<b>[[User:Runningonbrains|<span style="color:black;">Running</span>]][[WP:METEO|<span style="color:blue;">On</span>]][[User talk: Runningonbrains|<span style="color:green;">Brains</span>]]</b> 15:23, 9 October 2008 (UTC)
::::I have seen redlinks become a hindrance for FAC (see tropical cyclone).  In that article's case, it was because the red links for possible subarticles could have been (and were) used to help shorten the article, which was (and still is) large.  [[User:Thegreatdr|Thegreatdr]] ([[User talk:Thegreatdr|talk]]) 14:17, 8 April 2009 (UTC)
{{Talk:Noctilucent cloud/GA1}}

== Noctilucent Clouds versus Polar Mesospheric Clouds ==

I'd like to suggest that the search for polar mesospheric clouds not be automatically redirected to noctilucent clouds. Though the same tenuous ice crystal layer in the mesophere produces both physical phenomena, noctilucent clouds are the phenomena observed from the ground and polar mesospheric clouds are the scattering layer observed by satellite and LIDAR instrumentation. It is a subtle, but important distinction. I created a new article called [[Polar Mesospheric Clouds]] last night and would appreciate help writing and editing it.<small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Rss100001|Rss100001]] ([[User talk:Rss100001|talk]] • [[Special:Contributions/Rss100001|contribs]]) </span></small><!-- Template:Unsigned -->
:I agree with the new redirects. Good job on the new article, although it needs some [[WP:RS|reliable sources]]. -<b>[[User:Runningonbrains|<span style="color:black;">Running</span><span style="color:blue;">On</span><span style="color:green;">Brains</span>]]<sup>([[User talk:Runningonbrains|talk page]])</sup></b> 19:59, 10 June 2009 (UTC)
::On second thought, as it seems the consensus is that these are the same phenomenon, why should it not all appear in the same article? -<b>[[User:Runningonbrains|<span style="color:black;">Running</span><span style="color:blue;">On</span><span style="color:green;">Brains</span>]]<sup>([[User talk:Runningonbrains|talk page]])</sup></b> 20:07, 10 June 2009 (UTC)

==Noctilucent Cloud and Solar Minimum? ==

http://spaceweather.com/archive.php?view=1&day=18&month=06&year=2009

http://www.newscientist.com/article/dn17234-mysterious-nightshining-clouds-may-peak-this-year.html  <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/81.132.14.185|81.132.14.185]] ([[User talk:81.132.14.185|talk]]) 07:44, 19 June 2009 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->

I suggest including a reference to increased prevalence of noctilucent clouds during solar minima in the article, since there is considerably more evidence for this than for increased prevalence due to climate change.  Not to discount that possibility as well, of course, but having every imaginable kind of aberration that occurs being attributed to climate change is getting a little tedious and is damaging the credibility of climatology.   

[[User:TwoGunChuck|TwoGunChuck]] ([[User talk:TwoGunChuck|talk]]) 18:09, 12 August 2009 (UTC)

== Photos ==

Two photos in different sections are near-duplicates. Remove one?
[[User:Cognita|Cognita]] ([[User talk:Cognita|talk]]) 05:54, 30 June 2009 (UTC)

==First observation==
The first observation statement (first in section '''Discovery and investigation'''):
:''Noctilucent clouds were first observed in 1885, two years after the 1883 eruption of Krakatoa.[4]''
is extremely unlikely! [http://www.nytimes.com/2007/04/24/science/24cloud.html?_r=3&scp=3&sq=noctilucent%20cloud&st=cse&oref=slogin&oref=slogin The source] says:
:''A British <u>sky watcher</u> named Thomas William Backhouse was <u>perhaps</u> the first to notice the <u>odd blue wisps</u> in 1885, and many scientists thought that the phenomenon was an atmospheric effect caused by ash thrown up by the gigantic volcanic eruption of Krakatoa in Indonesia two years earlier.''
(my underlinings indicating the invalid citation usage) but living in Sweden and ''accidentally'' observing them every other summer, I think we should disregard that statement as speculative nonsense. It's infinitely more likely some Scandinavian, some Russian or Canadian scientist noted them much earlier. ... said: [[User:Rursus|Rursus]] ([[User talk:Rursus|bork²]]) 13:30, 14 July 2009 (UTC)

: What is the basis for claiming that these clouds weren't observed before 1885??? To the ordinary observer, they appear as normal clouds, albiet faint and silvery in the late evening and early morning. We only regard them as unusual today because we have instruments to measure their extreme height. So prior to the late 19th century, most scientific observers would have found them indistinguishable from late night cirrus clouds. This section of the article seems like the laziest kind of conjecture...
::Do you mean, "Why does that article claim they were only discovered in 1885"? That's easy: it's because that is what all the sources say. I have been scrupulous in recording only what can be attributed to reliable secondary sources, and no more- and that claim is attributed to two separate sources. [[User:Reyk|<span style="color:maroon;">'''Reyk'''</span>]] [[User talk:Reyk|'''<sub style="color:blue;">YO!</sub>''']] 02:44, 20 July 2010 (UTC)

== [[:File:Helkivad ööpilved Kuresoo kohal.jpg ]] to appear as POTD soon ==
Hello! This is a note to let the editors of this article know that [[:File:Helkivad ööpilved Kuresoo kohal.jpg ]] will be appearing as [[Wikipedia:picture of the day|picture of the day]] on March 22, 2012. You can view and edit the POTD blurb at [[Template:POTD/2012-03-22]]. If this article needs any attention or maintenance, it would be preferable if that could be done before its appearance on the [[Main Page]] so Wikipedia doesn't look bad. :) Thanks! ~[[User:AstroHurricane001|<span style="color:blue;">AH1</span>]]&nbsp;<sup>(''[[User_talk:AstroHurricane001|discuss]]!'')</sup> 01:48, 22 March 2012 (UTC) <!-- substituted from [[Template:UpcomingPOTD]] -->
{{POTD/2012-03-22}}
**Nice! Thanks for the heads up. [[User:Reyk|<span style="color:maroon;">'''Reyk'''</span>]] [[User talk:Reyk|'''<sub style="color:blue;">YO!</sub>''']] 04:15, 22 March 2012 (UTC)

== New source ==

A recent article I found on science daily, referencing a NASA report where the investigators/authors believe that 3 things are needed to form NLCs are cold temps, water vapor and space dust. Here is the citation info copied from the sciencedaily page:
NASA/Goddard Space Flight Center. "Appearance of night-shining clouds has increased." ScienceDaily. ScienceDaily, 11 April 2014. <www.sciencedaily.com/releases/2014/04/140411091939.htm>.  Just passing this along. [[User:Accidental contributor|Accidental contributor]] ([[User talk:Accidental contributor|talk]]) 06:10, 7 May 2014 (UTC)
*Thanks, nice find! [[User:Reyk|<span style="color:maroon;">'''Reyk'''</span>]] [[User talk:Reyk|'''<sub style="color:blue;">YO!</sub>''']] 06:14, 7 May 2014 (UTC)

== Links to anthropogenic global warming ==

A Wikipedia editor had provided a link to a site by the Australian Government Antarctic Division (http://www.antarctica.gov.au/about-antarctica/environment/atmosphere/noctilucent-clouds).  I removed the link because within the story itself the same comment was only provided as conjecture with no source data to back it up.  To whit, the article stated "It has been alternatively claimed that the appearance of noctilucent clouds is the earliest evidence of anthropogenic climate change." This was the identical text within the Wikipedia entry and with no source links or evidence to back up the claim.  These clouds have been observed since the 19th century, before the time that industrialization could have been claimed to cause anthropogenic global warming.  As was stated above in the talk section, they were not recorded before because up until that time there was no reason to suspect these clouds were different than normal cirrus clouds other than in luminosity.  This does not mean they did not exist prior to 1885, just as we cannot say atoms did not exist prior to the 19th century just because we did not have the means or science to measure or even theorize them.  <small><span class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Herefordnuthouse|Herefordnuthouse]] ([[User talk:Herefordnuthouse|talk]] • [[Special:Contributions/Herefordnuthouse|contribs]]) 15:03, 31 May 2014 (UTC)</span></small>
:I provided more substantial citations.--[[User:Smkolins|Smkolins]] ([[User talk:Smkolins|talk]]) 17:17, 31 May 2014 (UTC)

== Merge [[Polar mesospheric clouds]] into Noctilucent cloud ==

Basically the same subject. [[User:Pierre cb|Pierre cb]] ([[User talk:Pierre cb|talk]]) 13:36, 1 August 2021 (UTC)
:i agree , and i found it odd that both wiki and cloudatlas list 3 genus of clouds that exist above Tropospheric level , but wiki for some reason splits noctilucent clouds as 2 and merge the 2 Stratospheric clouds into one

:wiki: 1 stratospheric cloud | 2 mesospheric clouds
:cloudatlas:2 stratospheric clouds | 1 mesospheric cloud

:however the noctilucent clouds have 5 different (species,types,viarients?) it seems [[User:Joshoctober16|Joshoctober16]] ([[User talk:Joshoctober16|talk]]) 02:50, 4 August 2021 (UTC)
*I agree. A merge sounds like a good idea. [[User:Reyk|<b style="color: Maroon;">Reyk</b>]] <sub>[[User talk:Reyk|<b style="color: Blue;">YO!</b>]]</sub> 09:22, 4 August 2021 (UTC)
:{{merge done}} [[User:Klbrain|Klbrain]] ([[User talk:Klbrain|talk]]) 22:03, 19 December 2021 (UTC)

== GA concerns ==

I am concerned that this article no longer meets the [[WP:GA?|good article criteria]] due to uncited text, particularily in the "Description from satellites" section. Is anyone willing to address this concern, or should this go to [[WP:GAR]]? [[User:Z1720|Z1720]] ([[User talk:Z1720|talk]]) 02:47, 27 October 2024 (UTC)

==GA Reassessment==
{{Wikipedia:Good article reassessment/Noctilucent cloud/1}}