Difference between revisions of "2242: Ground vs Air"

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==Explanation==
 
==Explanation==
{{incomplete|Created by a THICK FIRE. More on the generawl thickness of the "ground" especially on the oceans and at the thcikest parts. Needs a title text explanation and more about the actual data portrayed}}
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{{incomplete|Created by a THICK FIRE. More on the general thickness of the "ground" especially on the oceans and at the thcikest parts. Needs a title text explanation and more about the actual data portrayed}}
 +
This comic asks the question, which is thicker the ground or the air? Hence the title ''Ground vs Air''.
  
This is a map comparing the thickness of the ground, apparently referring to the {{w|lithosphere}}, and the thickness of the {{w|atmosphere}}. It shows where the lithosphere is thicker than 100 km, the boundary between Earths atmosphere and space.
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It depicts a map of the world comparing the thickness of the ground, which refers to the {{w|lithosphere}}, and the thickness of the air above it, which refers to the {{w|atmosphere}}. It shows where the lithosphere is thicker than 100 km by shading these areas gray. 100 km is the official boundary between {{w|Earths}} atmosphere and {{w|space}}, . This almost only occurs over continents, and certainly only where the continental plates are located (which can stretch into the shallow parts of the oceans). But there are several sections over oceans where the crust is thinner than 100 km.
  
 
[[Randall]] always uses the {{w|Kármán line}} (the altitude of 100 km ≈ 62 mi) as the boundary between Earth's atmosphere and space. He has previously mocked the alternative definition of the atmosphere boundary (at 80 km ≈ 50 mi) used by US Air Force and NASA in the title text [[1375: Astronaut Vandalism]]. That definition would of course have resulted in a significantly different picture where the ''air'' is thicker than the ''ground'' only inside small areas around mid-ocean ridges.
 
[[Randall]] always uses the {{w|Kármán line}} (the altitude of 100 km ≈ 62 mi) as the boundary between Earth's atmosphere and space. He has previously mocked the alternative definition of the atmosphere boundary (at 80 km ≈ 50 mi) used by US Air Force and NASA in the title text [[1375: Astronaut Vandalism]]. That definition would of course have resulted in a significantly different picture where the ''air'' is thicker than the ''ground'' only inside small areas around mid-ocean ridges.
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In an inserted figure Randall defines four layers. At the top is {{w|space}} (vacuum), and then the atmosphere goes to the ground, where [[Cueball]] is standing (obviously not to scale). Also the oceans have been indicated in this drawing. Beneath the surface is the lithosphere, and beneath this is the {{w|Asthenosphere}} which is the highly viscous region of the {{w|upper mantle}} of the Earth. The two thicknesses compared are indicated by arrows going from space to surface and from surface to Asthenosphere. And between them is a double line with a questions mark on it.
  
 
The title text referrers to the ancient four {{w|classical element}}s earth, water, air, fire. The lithosphere, or ground, is earth, the oceans is water, the atmosphere is air, and fire would thus be the various magma layers underneath the crust down to the center of the core. See [[913: Core]]. The water layer on Earth is never more than 11 km deep at the {{w|Mariana Trench}}, and thus cannot compare to the thickness of the atmosphere or the lithosphere. Whereas there is fire all the way into the core so this layer is either 6000 km thick, or 12000 km, depending if Randall would look at the depth to the center or to the entire diameter of Earth. In either case it would always be much thicker than the roughly 100 km or the other two layers.
 
The title text referrers to the ancient four {{w|classical element}}s earth, water, air, fire. The lithosphere, or ground, is earth, the oceans is water, the atmosphere is air, and fire would thus be the various magma layers underneath the crust down to the center of the core. See [[913: Core]]. The water layer on Earth is never more than 11 km deep at the {{w|Mariana Trench}}, and thus cannot compare to the thickness of the atmosphere or the lithosphere. Whereas there is fire all the way into the core so this layer is either 6000 km thick, or 12000 km, depending if Randall would look at the depth to the center or to the entire diameter of Earth. In either case it would always be much thicker than the roughly 100 km or the other two layers.

Revision as of 10:55, 17 December 2019

Ground vs Air
Water is thinner than both, and fire is *definitely* thicker.
Title text: Water is thinner than both, and fire is *definitely* thicker.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a THICK FIRE. More on the general thickness of the "ground" especially on the oceans and at the thcikest parts. Needs a title text explanation and more about the actual data portrayed
If you can address this issue, please edit the page! Thanks.

This comic asks the question, which is thicker the ground or the air? Hence the title Ground vs Air.

It depicts a map of the world comparing the thickness of the ground, which refers to the lithosphere, and the thickness of the air above it, which refers to the atmosphere. It shows where the lithosphere is thicker than 100 km by shading these areas gray. 100 km is the official boundary between Earths atmosphere and space, . This almost only occurs over continents, and certainly only where the continental plates are located (which can stretch into the shallow parts of the oceans). But there are several sections over oceans where the crust is thinner than 100 km.

Randall always uses the Kármán line (the altitude of 100 km ≈ 62 mi) as the boundary between Earth's atmosphere and space. He has previously mocked the alternative definition of the atmosphere boundary (at 80 km ≈ 50 mi) used by US Air Force and NASA in the title text 1375: Astronaut Vandalism. That definition would of course have resulted in a significantly different picture where the air is thicker than the ground only inside small areas around mid-ocean ridges.

In an inserted figure Randall defines four layers. At the top is space (vacuum), and then the atmosphere goes to the ground, where Cueball is standing (obviously not to scale). Also the oceans have been indicated in this drawing. Beneath the surface is the lithosphere, and beneath this is the Asthenosphere which is the highly viscous region of the upper mantle of the Earth. The two thicknesses compared are indicated by arrows going from space to surface and from surface to Asthenosphere. And between them is a double line with a questions mark on it.

The title text referrers to the ancient four classical elements earth, water, air, fire. The lithosphere, or ground, is earth, the oceans is water, the atmosphere is air, and fire would thus be the various magma layers underneath the crust down to the center of the core. See 913: Core. The water layer on Earth is never more than 11 km deep at the Mariana Trench, and thus cannot compare to the thickness of the atmosphere or the lithosphere. Whereas there is fire all the way into the core so this layer is either 6000 km thick, or 12000 km, depending if Randall would look at the depth to the center or to the entire diameter of Earth. In either case it would always be much thicker than the roughly 100 km or the other two layers.

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Caption above the comic]:
Which is thicker—the ground or the air?
[A Winkel tripel projection of the Earth. The map is mostly unlabeled, with only the outlines of the landmasses present. Various parts of the map are labelled with "Air" or "Ground." Areas marked as "Ground" are differentiated with gray shading.]
[A small diagram is present in the Pacific Ocean left of South America. The diagram depicts several labelled layers of Earth and its atmosphere, listed below. Cueball, a body of water, and several mountains are shown on the surface part of the diagram. Two arrows representing the thickness of the atmosphere and lithosphere are marked with a question mark.]
Space
Atmosphere
Lithosphere
Asthenosphere
[Gray text in the bottom right corner of the comic]:
Based mostly on Conrad and Lithgow-Bertelloni (2006) DOI.1029/2005GL025621


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Discussion

Wow; it took longer than I care to admit to realize 'thick' wasn't 'viscosity'...but 'altitude'. (i.e., height/thickness re: Kynde's comment) Elvenivle (talk) 01:08, 17 December 2019 (UTC)

Ohhhhhhhh! Sdkb (talk) 02:38, 17 December 2019 (UTC)
Not altitude, but height or thickness... --Kynde (talk) 11:03, 17 December 2019 (UTC)
^ Yes, that. Correction added; I meekly blame word choice on keyboard dead zones. Elvenivle (talk) 20:22, 17 December 2019 (UTC)

A link to the article is here: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2005GL025621. 162.158.186.192 01:12, 17 December 2019 (UTC)

It's probably worth mentioning in the explanation which map projection Randall chose to use for this comic from those listed in a previous comic about map projections. Ianrbibtitlht (talk) 02:22, 17 December 2019 (UTC)

And by these metrics, blood is even thinner than water... Template:unsignedip

But everything changed when the fire nation attacked 108.162.229.250 10:47, 17 December 2019 (UTC)

I assume ocean ridges have a very thin crust, meaning they get the ratio more towards air? I am not at all a geologist, so I ask this question, because ridges would intiutively appear to have a bigger crust, as they stand out from the ground. "That definition would, of course, have resulted in a significantly different picture where the air is thicker than the ground only inside small areas around mid-ocean ridges" should be explained by someone who knows why it is the case. --Lupo (talk) 14:26, 17 December 2019 (UTC)

Mid-ocean ridges can even be raised above the ocean surface--Iceland is actually the high point on one of them. In other places they're trenches, though. Since seafloor crust is spreading at those points, it's at its thinnest there on average. Nitpicking (talk) 02:08, 18 December 2019 (UTC)
Would you feel confident, adding that in a concise way to the explanation? I do not... But I am glad I learned something by that. That might also explain why these ocean ridges tend to be equipped with volcanoes. I thought the reasoning was the other way round: They are ridges due to their geothermal activity. --Lupo (talk) 07:27, 18 December 2019 (UTC)
I have done this! And added a bit more earth science knowledge besides. And while Iceland is the highest point on the ridge, I'm not sure I'd say it's actually because of the ridge - Iceland is a hot spot the same way Hawaii (which is not on a ridge) is.108.162.219.62 21:29, 30 January 2020 (UTC)

The current explanation seems to include water-thickness in with (either) air or ground thickness in discussing it in the initial transition from air to ground. Depends how you read it, which, but it easily reads as either. Maybe edit that aside out from that bit, then make sure that sliver of water is gone into later (...end of that para? ...footnote mention?) that sometimes the air ends at sea-level and ground starts after the depth of sea? 162.158.34.46 12:28, 18 December 2019 (UTC)

Just done what I think you asked for, as luck would have it. (And then redid it slightly to avoid adjectival and verb forms of "separate" appearing so close together.) 162.158.154.91 19:46, 18 December 2019 (UTC)

The current explanations refers to fire as being 12000km, I would rather go with the radius of 6000km. Makes more sense to me since we are on a sphere and not counting the crust thickness twice.108.162.216.52 17:52, 18 December 2019 (UTC)

Should we make a Comics with Citations category? Seems like it's warranted 141.101.69.53 19:21, 18 December 2019 (UTC)

XKCD is he only webcomic where mentioning the type of map projection in an explanation would not be needless pedantism. —Kazvorpal (talk) 18:52, 22 January 2020 (UTC)