Talk:Weather radar

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WikiProject Meteorology (Rated C-class, High-importance)
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WikiProject Meteorology (Rated C-class, High-importance)
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Not finished?[edit]

Sorry but the article is not finished yet but the structure is:

  • Historical facts.
  • Description of what is specific to weather radar compared to other radars.
  • Products available with the data obtained
  • Limitations of weather data

To my knowledge, an encyclopedic article should explain the ins and outs of a subject not only light talk.

Pierre_cb 02:37 GMT 2006-05-15

Sounds like a good outline plan. My main motivation for tagging the article with "cleanup" was:
  • Formulas are presented without proper description and derivation. It is e.g. impossible to determine what P_r,\ P_t,\ G,\ \sigma etc. stands for.
  • Engeneering rule of thumbs and examples, like e.g: "of 300 m and beam width of 1 degree, this gives a scanned volume of 0,001 km3 at 10 km range and of the order of one kilometer3 at 200 km", should be moved into separate "examples" subsection, since they provide little general insight into the underlying principles of weather radars. --Fredrik Orderud 18:01, 15 May 2006 (UTC)
Good points, the P_r,\ P_t,\ G,\ \sigma comes from the radar article and I assumed wrongly that it would be obvious. So I will restate them as I did in other equations.
As for the "rules of thumbs", that you mention, they probably lack context For instance, the example you mention about the scanned volume is very important as the radar beam sample on different size volumes with distance which affect the average of the return. I wanted the reader to have an idea already but I should probably elaborate. Maybe I should transfert it to the last section on limitations where I will detail the hypothesis and limitations of weather data.
If you have more suggestions, don't hesitate. Pierre_cb 20:32 GMT 2006-05-15

I hope someone nominates this as a FAC[edit]

Bravo to the editors of this article. I hope someone meeting the criteria can nominate this article for Wikipedia:Featured article candidates.

I have a lay understanding on the subject matter as an Air Force Veteran but I am far from a subject matter expert, and was thrilled to see an article balance the science and math so well without making the article completely unapproachable to the rest of us.

It seems that so many science articles get hijacked by subject matter experts who transform the article into a post-graduate level thesis, and which can only be understood by their academic or professional peers. These contributors often scoff at criticisms that their articles need to be made more approachable to the everyday user.

This article on the other hand appears to be very comprehensive, sacrificing none of the science while making it a joy to read for those seeking every day knowledge on a matter that affects all of our lives. Tolstoy143 - "Quos vult perdere dementat" (talk) 13:12, 28 January 2009 (UTC)

Completion[edit]

My input for the article is now complete. I've tried to be as Wiki as I know. If anyone has comments on the material or layout, I would like to hear them.

Pierre_cb 14:41 GMT 2006-05-17

To do[edit]

  • The history section should be converted to prose-style, as opposed to a list of events.
  • Where possible, use non-technical language.

Runningonbrains 21:24, 2 September 2006 (UTC)

Question: How do you talk about a technical subject without using well explained technical terms? Looking for seeing that. Pierre cb 11:43, 4 September 2006 (UTC)
We had the same problem in the extratropical cyclone article. I'd mention a simple description of the technical terms, when and where they are first used. Thegreatdr 23:59, 9 December 2006 (UTC)
Well, the problem comes when technical terms aren't explained, and compounded when poor writing confuses even technical readers. I'm working on fixing these kinds of problems with this article; I'll ask some particular technical questions so we can clear things up. -- Beland 02:51, 2 January 2007 (UTC)

Frequencies[edit]

What frequencies bands do weather radars use? S-band links to this article, for example. -- Beland 22:12, 17 December 2006 (UTC)

Weather radar uses wavelenghts that are typically 10 times the diameters of the targets in order to obey the Rayleight law. That means centimetric wavelengths and usually 1 to 10 cm. The shorter the wavenlength the more attenuation, so 10 cm (S-band) is favored but its cost is greater so 5 cm C-band is often used. 3 cm X-band is used only in very short distance radars and 1 cm Ka band (corrected from L-Band) only for research of drizzle and fog. All this is mentionned in the article, in particular in the "Principles of radar in meteorology" section. Pierre cb 04:48, 18 December 2006 (UTC)
Interesting. I'll add your explanation to the article. Thanks! -- Beland 02:19, 2 January 2007 (UTC)
In frequencies bands, L Band is between 15-30 cm not 1 cm. — Preceding unsigned comment added by Jhawri (talkcontribs) 19:03, 5 February 2012 (UTC)
Sorry, the old definition of the 1 cm wavelenght band was L-Band. It is now Ka band. I have corrected in the above comment. Pierre cb (talk) 04:44, 17 February 2012 (UTC)

Pulse volume formula[edit]

  • It looks like the beam width "theta" is supposed to be the diameter of the cross-section of a beam which is assumed to be circular? Is that an accurate assumption?
  • Is the radius "r" supposed to be the calculated from the beginning, middle, or end of the pulse? Is the h*r^2*theta^2 formula approximate or exact?

-- Beland 03:10, 2 January 2007 (UTC)

The volume calculation is equivalent of calculating the volume of a slice of a think sphere skin. This is an approximation of the real volume at distance "r" from the radar since a real radar beam is very complexe and the volume is really a truncated cone, not a circular slice. le formula assume that "r^2 \theta^2" to be the area of the sphere intercepted by the angle \theta from one side to the other of the beam center where energy falls by half. "r" is usually taken at a distance where r>>h. Since h is about 200 meters in weather radars, "r" can be using beginning, middle or end of pulse distance with little difference if at 10 km of more. I will add information on that in the text. Pierre cb 02:03, 12 April 2007 (UTC)


It's a fairly complete article[edit]

...but it will get more attention both within wikipedia and the meteorology project if it achieves GA. We can't begin to consider it for GA without inline references, roughly one per paragraph or important fact, regardless of content. Make it so, and it will be nominated. Right now, it wouldn't have enough references to pass. Thegreatdr 14:56, 22 June 2007 (UTC)

Good stuff, but the equations absolutely have to go if this is to appeal to a general audience. --Beaker342 04:18, 21 September 2007 (UTC)

Urban Spike?[edit]

In the section 'Solutions For Now And The Future', the image on the left has something labeled an 'urban spike', but this term is not mentioned anywhere in the article. What is it? PolarisSLBM 17:05, 18 August 2007 (UTC)

Reflection of the radar beam on buildings. I will define in the text, thanks for mentionning. Pierre cb 19:16, 18 August 2007 (UTC)

Dual polarization credited with saving many lives[edit]

I don't think that dual polarization helped as much as the news article claimed, but that the author saw that the radar was recently upgraded and came to the conclusion that the upgrade helped a lot. Dual polarization is only really useful in finding a TDS, but by that time it's too late to issue a timely warning. What do you guys think? Michael73072 (talk) 12:41, 1 March 2014 (UTC)

I agree with you, dual polarization is much more important for precipitation types (snow, rain, hail, etc...). When the tornado debris are dense enough to be seen on radar, the tornado has touch down for a while. I removed the comment in the article as it is not a NOAA claim. Pierre cb (talk) 14:01, 1 March 2014 (UTC)