User talk:Pierre cb

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Category: Cloud-to-cloud lightning[edit]

How did you infer it for File:120516-N-UM734-1066 (7243619354).jpg? Incnis Mrsi (talk) 17:13, 9 February 2018 (UTC)

  • There is no indication that the lightning is touching the surface of the sea. So it cannot be cloud-to-ground.
  • The source is somehere above the ship structure but is not visible as one can juge by the brightness there and the branching of the lightning to the left.
  • One can see that the lightning extend well beyond the generating cloud laterally too. So it cannot be in-cloud lightning.
  • The description of the image says that the lightning is "over the amphibious assault ship USS Kearsarge".
Unless you have more information than the image can provide, cloud-to-clouds is the best that can be inferred.

Pierre cb (talk) 18:21, 9 February 2018 (UTC)

The surface of the sea? Should it, really, if the ship itself is a decent conductor? Incnis Mrsi (talk) 18:23, 9 February 2018 (UTC)
  • @Incnis Mrsi: This has nothing to do with the conducting property of the ship (which are good) compared to the sea. The lightning is clearly heading away from the ship: look at the branches that diverge toward the left. There is no indication that the ship was touched in the description ... "over the amphibious assault ship USS Kearsarge". Pierre cb (talk) 18:29, 9 February 2018 (UTC)
Unsure what means you are in meteorology, but “lightning is heading away” is not a serious description. A lightning connects two spatial regions having a high voltage between them. It may have branches, and some of them have direction far from vertical (look at File:CG lightning strike.JPG for example). The “branches that diverge toward the left” lead to a cloud under a high voltage. The other end of the lightning is obscured by interposing ship structures and may lie out of the frame even if the lightning strikes the ship. Conducting properties of the ship, indeed, are very important because a lightning strike doesn’t cause significant damage, or even observable effects, on thick metal-grade conductors (unlike such materials as carbon fibre). Hence, I suggest to leave the navy image in Lightning although will not wage a war over it. Incnis Mrsi (talk) 19:12, 9 February 2018 (UTC)
@Incnis Mrsi: The category "Lightning" is a mother category and should be kept empty, all images transferred toward sub-categories, otherwise it will be overflowing in no time. You may not like my vocabulary but it is adapted to the description, maybe would have like that I use "leads" instead of "branches" but I will not rewrite here all the theory of lightning propagation. Cloud-to-cloud category is the best with the indications available on the photo, as I said in my first intervention. One cannot deduce more than the image shows and its description says. Pierre cb (talk) 20:00, 9 February 2018 (UTC)
I have created a new category to satisfy you : Category:Lightning at sea. Pierre cb (talk) 20:07, 9 February 2018 (UTC)