Talk:Numerical weather prediction

message: The information from this page needs to be merged with another recently created Numerical Weather Prediction page
Numerical Weather Prediction
: Done. nick 15:42, 11 May 2005 (UTC)
thread_title:  Possible merger 

message: ...it needs inline citations.  Thegreatdr (talk) 19:18, 13 January 2008 (UTC)
thread_title:  If the article is ever to go to GAC... 

message: Both this article and the "Atmospheric model" article contain a section "Global models" which is a list of models.  Theses are similar but look to have diverged a little. Not nice. So I suggest that this list be maintained in just one article (not both), and that the other article contains a cross-reference (e.g. wikilink) to that first article. If that is the right way to go, my guess is that this (NWP) article might be the better home, as some models are (presumably) more than just atmospheric. Feline Hymnic (talk) 23:30, 1 January 2009 (UTC)
replies: text: If there is no difference between the Atmospheric model article and this article, the better idea would be to suggest their merger, making Atmospheric model a redirect to this article.  That would require a vote amongst the editors, and some time.  Thegreatdr (talk) 23:35, 1 January 2009 (UTC)
replies: text: But aren't they different (although overlapping) topics? "Atmospheric model" is, presumably, just about the atmosphere, whereas NWP is more general and would include other coupled systems (e.g. oceans), wouldn't it? So wouldn't it be better to keep them separate (although well-defined, and well-focussed on their respective primary topics)? Feline Hymnic (talk) 23:53, 1 January 2009 (UTC)
replies: text: That would certainly be easier.  If kept separate, the list of forecast models could disappear from this article.  Thegreatdr (talk) 00:00, 2 January 2009 (UTC)
thread_title:  Global models (list) 

message: We're down to two sections which remain reference-less, and a few other passages which need refs.  Some external links likely need to be weeded out.  Other than a little more content, significant progress has been made improving this article during this past week, and I can see GAN on the horizon.  Thegreatdr (talk) 18:49, 1 January 2011 (UTC)
replies: text: For the initialization section, do we need to write about individual objective analysis techniques, such as successive correction, optimal interpolation, or the 3D/4D variational assimilation methods? Titoxd(?!? - cool stuff) 20:50, 2 January 2011 (UTC)
replies: text:   For FA, maybe.  For GA, probably not.  Really, all that stuff should be gone into detail within the article about objective analysis techniques (if wikipedia has one).  Thegreatdr (talk) 20:56, 2 January 2011 (UTC)
replies: text: Interestingly, wikipedia does not have an objective analysis article.  There is definitely room for one as a subarticle to this article, as well as any article while requires mention of providing initializations for computer programs.  Barnes interpolation is the closest article I could find which addresses this issue.  Thegreatdr (talk) 23:52, 2 January 2011 (UTC)

text: Oh, I didn't see that one. I don't think that an additional citation in the lede is necessary. Titoxd(?!? - cool stuff) 21:23, 2 January 2011 (UTC)
replies: text:  Referencing for the current content of this article is finally done (I think).  Whenever we are comfortable with its content, we should be able to GAN it.  Thegreatdr (talk) 01:10, 3 January 2011 (UTC)
replies: text:  I'm happy with it. One question, though: How much history of climate models should we mention here? We have a Global climate model, and I'm not sure how much should go here instead of there. Titoxd(?!? - cool stuff) 02:13, 3 January 2011 (UTC)
replies: text:   This is the parent article of that one.  A simple summary should suffice, an additional line or two.  We already have one line about it.  It actually may not be a bad idea to mention air quality models too, if the info could be found.  I don't think hydological modeling has reached this point...though last I heard, it's on the cusp of it. Thegreatdr (talk) 06:04, 3 January 2011 (UTC)
replies: text:  But are the latter two really "weather" models? They are fluid dynamics models, certainly, but those seem too far detached from weather forecasting to be in this article, IMO. Titoxd(?!? - cool stuff) 06:25, 3 January 2011 (UTC)

text: I believe that's the biggest problem with ECMWF images...copyright.  I swapped it out for an image which was previously further down the article, which might be better suited within the lead.  Thegreatdr (talk) 15:26, 6 January 2011 (UTC)
thread_title:  Progress so far 

message: So what is left to do before a GAN/FAC run? Titoxd(?!? - cool stuff) 04:46, 12 January 2011 (UTC)
replies: text: I don't know.  I think we responded to Feline's useful input.  Bitewise, we've quadrupled the size of the article since we began.  I significantly improved one of the subarticles, sea surface temperature, over the weekend, and tried to make the barotropic model wikilink/subarticle more understandable.  We could probably safely GAN this now.  Any other input?  Thegreatdr (talk) 09:50, 12 January 2011 (UTC)
replies: text:  I posted the GAN. I think that we could probably try our luck at FAC as soon as the GAN is complete, assuming everything goes well. Titoxd(?!? - cool stuff) 00:21, 13 January 2011 (UTC)

text:  look at that spike Titoxd(?!? - cool stuff) 09:56, 13 January 2011 (UTC)
thread_title:  What's left? 

message: Do we go for the bronze star? Titoxd(?!? - cool stuff) 02:15, 18 January 2011 (UTC)
replies: text: We could.  I wish others from the project would have helped out.  Oh well.  Did you want to go through a peer review first, or is that unnecessary?  Thegreatdr (talk) 23:25, 23 January 2011 (UTC)
thread_title:  So we have the [[WP:GA|green plus sign]] 

message: * A reviewer in the FAC asked for links to prognostic chart and spaghetti diagram. While the first one probably doesn't have enough content to have a separate article, the second one could be made into a stub with a picture rather easily. Titoxd(?!? - cool stuff) 19:51, 13 February 2011 (UTC)
thread_title:  Random to-do's 

message: The following sentence in the lead raises some questions in my mind:
: ...the chaotic nature of the partial differential equations that govern the atmosphere...
First, the use of the word 'govern' here seems odd. I would think that the equations model the behavior of the atmosphere, rather than govern it. Second, are the equations themselves chaotic, or is it the fact that any small imprecision in the input causes a chaotic variation in the output? Thank you.—RJH (talk) 20:16, 21 February 2011 (UTC)
replies: text: You're right, govern was inappropriate there.  Otherwise, both issues you mention cause the errors within forecast guidance to grow with time...initial uncertainty and the solutions from the partial differential equations, where various assumptions are made.  Some studies indicate that with increasing resolution, the "assumptions" made in the forecast guidance (the statistically-based model parameterizations) also introduce increasing amounts of error.  Thegreatdr (talk) 20:25, 21 February 2011 (UTC)

text: (edit conflict) Well, in respect to the first point, "governing equations" in engineering and science is the term used to describe the model used to simulate some process. That should probably be reworded since it's a bit jargony. As for chaos, it's both: the second part (infinitesimal imprecisions in the input resulting in large, finite changes in the output) is essentially the definition of a chaotic process, so the equations themselves are said to be chaotic. Titoxd(?!? - cool stuff) 20:26, 21 February 2011 (UTC)
replies: text:  Okay, thank you.—RJH (talk) 20:43, 21 February 2011 (UTC)
replies: text: "Governing equations" is correct; see e.g.. Also it is indeed the chaotic nature of the coupled equations that causes error in the initial conditions to grow. The system is chaotic regardless of the magnitude of the initial error. Short Brigade Harvester Boris (talk) 21:07, 21 February 2011 (UTC)
thread_title:  Question about a sentence in the lead 

message: Congratulations! Good work! Nageh (talk) 17:21, 3 April 2011 (UTC)
replies: text: The link you were posting does not even mention anything about numerical weather prediction. It's a general timeline about U.S. history. Titoxd(?!? - cool stuff) 02:01, 10 August 2011 (UTC)

text: Just the US History here, too. Nageh (talk) 13:17, 10 August 2011 (UTC)
thread_title:  FA promotion 

message: It is impossible to solve these equations exactly, and small errors grow with time (doubling about every five days).
And yet we can predict to a tenth of a degree the temperature in 80 or 90 years. Imagine that.  — Preceding unsigned comment added by 24.250.206.199 (talk) 04:58, 10 August 2011 (UTC)
replies: text: The temperature in 80 or 90 years is a matter of climate, which can, in some respects, be interpreted more accurately decades in advance than weather can be predicted 24 hours out. The weather is different from city to city, usually street to street, and very often from house to house; it tells us things like the transient temperature, weather conditions at a specific point (whether it's raining, snowing, overcast, clear, etc). Climate is much more broad, and isn't so much a matter of trying to pinpoint where it'll rain next as looking back in the past, figuring out what's going on now, and (largely) extrapolating it well into the future. Juliancolton (talk) 13:10, 10 August 2011 (UTC)
thread_title:  And yet... 

message: "height or pressure" you mean "height AND pressure" right?  — Preceding unsigned comment added by Odarcan (talk • contribs) 21:56, 10 August 2011 (UTC)
thread_title:  the pic on the right 

message: Milutin Milanković should be mentioned in this article because he initiated numerical modeling of the climate.--Свифт (talk) 09:21, 4 April 2012 (UTC)
thread_title: Numerical modeling

message: I understand that data assimilation is a major component of NWP.  But contrast the state of this NWP article (very good) and the DA article (distinctly less good).  Could some of the NWP-knowledgable editors turn their attention to the DA article, please?  Feline Hymnic (talk) 00:19, 19 October 2013 (UTC)
thread_title:  Data assimilation? 

message: /there are some semantic issues though/
The probability of the occurrence of a weather phenomenon (e.g. precipitation)
is the expected value (of that phenomenon occurring) 
of a large number of virtual outcomes,
for certain periods of time (quanta of time)
and the amount of a specific measurable effect of that weather phenomenon (over a threshold)
over each unit of time.  — Preceding unsigned comment added by 2.84.222.127 (talk) 19:27, 16 August 2015 (UTC)
thread_title:  Older definition of weather prediction 

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thread_title:  External links modified 

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thread_title:  External links modified 

message: *Numerous unsourced statements, including an entire section
*Grammatical errors throughout
*References are outdated in some areas
*Some sections are in need of an update material/coverage-wise as well
:* Surely something has happened since the 1990s that can be added to the history section
:* I see plenty of new scholarly sources out about this topic
I am listing this article at WP:FARGIVEN due to its numerous issues. NoahTalk 23:01, 4 December 2021 (UTC)
replies: text: Likely copyright violation detected. Needs further checks. NoahTalk 23:05, 4 December 2021 (UTC)
thread_title:  [[WP:URFA/2020]]