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It seems like the link to the Magnetic field article should go to the Earth's magnetic field article, which is more specific and pertinent. From there, if you really just want to know about magnetic fields, it's linked.
The following part of the article contains several strange facts that need to be cheked.
Telluric currents will move between each half of the terrestrial globe at all times. Telluric currents move equator-ward (daytime) and pole-ward (nighttime).
The field varies in time and over the frequency range 0.001 to 5 Hz (Krasnogorskaja & Remizov, 1975). Electric potential gradients caused by telluric currents are of the order of 0.2 to 1000 volts per metre. (Krasnogorskaja and Remizov, 1975; Vanjan, 1975). At any location, the current density is a direct function of the interhemispheric currents and their potential gradients. It has been estimated that telluric currents overall during twelve hours in one hemisphere are in range of 100 to 1000 amperes. This intensity of telluric currents is sufficient to drive the air movements that create atmospheric electricity, from the global fair weather charge accumulator to thunderstorm bases.
If the currents variate daily they have a frequency of 1/24/3600 Hz = 0.0000115 Hz.
The potential gradients seems to be way to high 0.2 V/m is 200 V/km enough to run normal lamps from the potential differance over 1000 m. 1000 V/m is even enough to give a dangerous voltage between your feet. I have heard of 10 V/km during solar eruptions.
The sentence "It has been estimated that telluric currents overall during twelve hours in one hemisphere are in range of 100 to 1000 amperes." gives no meaning current does not accumulate over time, they are measured at any given moment. To me the numbers seams ridicules low, could It be per km?
As I understands it so are telluric currents not the source of air movements and thunderstorms. The article on Atmospheric electricity does not mention it more than under "se also".
I don't know where to find Krasnogorskaja & Remizov, 1975, if some one has know pleas check the facts. I will remove the section since at least some of the statements are wrong. Pleas reinsert it when we are sure of the correct numbers.
The article contradicts itself, describing the currents moving near the surface only in two places and through the "mantle":
"...and travel over large areas at or near the surface of the Earth."
"Telluric currents are phenomena observed in the Earth's crust and mantle."
"Telluric currents flow in the surface layers of the earth."
What does this mean -- clarify -- was there some ground transmission method that was used during sunspots or whatever? Why wasn't it used all the time? How did the telegraph system switch from using wires to the ground when needed?
"Utilization of these electromagnetic effects has been reported in the United States as far back as 1859. United States telegraph lines were operated by such natural induced currents (during geomagnetic disturbances)." —The preceding unsigned comment was added by 18.104.22.168 (talk) 10:35, 23 December 2006 (UTC).
Seems to be a power source -- see Earth battery -- I am removing reference to geomagnetic disturbances and reworking a bit. Correct if inaccurate.
Earth batteries were used, but more commonly artificial telluric currents were induced by single wire telegraphs using the earth as a return path to complete the circuit. This system halved the wire needed, but was vulnerable to crosstalk and remote eavesdropping. Enon (talk) 02:10, 11 August 2010 (UTC)
After mentioning magnetosphere and lightning, needs to mention what human activities create currents. —The preceding unsigned comment was added by 22.214.171.124 (talk) 10:57, 23 December 2006 (UTC).
A Living Earth?
Let us suppose for a moment that everything is interconnected, that the structure of the smallest item can be a model for the largest. For example, just as the human body has an intricate network of nerves that are not only sensitive to external stimuli, but are also tuned to the events that happen within the body, the same might be said concerning the magnetic 'structures' of the Earth and the Universe as a whole. In other words, that each living organism is a universe within itself. And concerning Earth: perhaps it's time we started considering Earth as a living entity :itself, reacting to both internal and external stimuli as theories about Telluric Currents :suggests. If we can learn to see Earth from this perspective, then perhaps we can have a greater :understanding of ourselves and the Universe.
As for humanity's influence upon Earth's Telluric Currents, Global Warming, the hole in Earth's Ozone Layer and the increase in natural disasters(eruptions of seemingly dormant volcanos, earthquakes, flooding, droughts, etc.) seems to suggest that this might be the case.126.96.36.199 14:20, 16 July 2007 (UTC)
Please read WP:SOAP. This page is for discussing improvements to the article, and I cannot see how anything you have said could result in an improvement to this article. SHEFFIELDSTEELTALK 17:13, 16 April 2008 (UTC)
Include Patents later
The United States Patent office has a division classification for geophysical electrical measuring devices of the telluric type [class 324/349] (including magneto-telluric types [class 324/350]). Other patents have utilized the earth's current outside this classification, also.
There's some disagreement about whether this article (and some others) should contain a list of patents. Rather than edit war, it'd be better for the involved editors to discuss the matter here, and for other editors to offer input. I'm not offering an opinion at this time, but I note that WP:LISTS provides some guidelines on the subject, and that another editor has stated that WP:NOT#DIRECTORY applies. SHEFFIELDSTEELTALK 20:18, 16 April 2008 (UTC)
Editors seem not to want to discuss this .. just do do what they want. Disgusting! J. D. Redding
Patents are a very poor form of external link to add. They are often irrelevant to the article, reading them—should anyone do so—sheds little light on the subject matter, and more often than not, they form no more than an end-of-article linkfarm. — BillCtalk 22:39, 16 April 2008 (UTC)
Are you serious? I hope not. Do you know anything about relevant patents on this or many other topics? How many patents have you really read?
So the marconi patents or edison patents are irrelevant to marconi and edison respectively?
Many great engineers and scientists have patents. I would take thier patented works and own words over many other words about them. such as I would rather see Van de graff's and Enrico Fermi's own words over many other people views of them. J. D. Redding 02:47, 17 April 2008 (UTC)
How does WP:PSTS apply to this? I would characterise a patent as a reliable source, but also a primary source. What is the significance of a given patent? Is it notable? In many ways, that depends on who has obtained a license to exploit the patent commercially. To know this, we need a reliable secondary source to interpret the primary source - something we should not attempt to do ourselves. Just throwing this into the mix. SHEFFIELDSTEELTALK 12:58, 17 April 2008 (UTC)
Many patents are secondary sources themselves. They make make analytic or synthetic claims over the topic they cover [citing previous work]. J. D. Redding 16:51, 17 April 2008 (UTC)
I haven't been involved with this particular article, so I won't comment on the specific patents in question here. In general, though, I think that large lists of patents are generally not appropriate in Wikipedia articles. It's OK to cite a patent as a reference for a specific statement or paragraph within the article. Otherwise, patents should be carefully selected to be historically or technically significant, and should be directly relevant to the topic of the article. Wikipedia is not a patent directory, so even relevant and significant patents should be kept to a limited number except in unusual cases. I agree with BillC that patents are often (but not always) poor external links, and that they often shed little light on the subject. I have read many patents and have one myself, so I know how to read them. Readers without experience with them are likely to find them less useful, however.--Srleffler (talk) 20:19, 17 April 2008 (UTC)
Patents are not reliable sources for anything other than that a patent exists. It is not appropriate to add patents, especially long lists of patents, to articles such as generalised science articles such as this one. An appropriate place to add a patent link would be in an article about an invention: for example, Rudolf Diesel invented the diesel engine in 1892; a single link to his patent is entirely fitting in that article. — BillCtalk 00:44, 18 April 2008 (UTC)
Everybody seems to be in agreement about removing the patents from this page except for User:Reddi. The proper course of action is to say that consensus has been reached and close the matter. ScienceApologist (talk) 01:10, 18 April 2008 (UTC)
BillC: Your first sentence is a bit too narrow. Patents are particularly useful as a source for who invented something and when. They can be useful as sources for detailed information about an invention. I agree their use as sources is limited, however.--Srleffler (talk) 06:10, 18 April 2008 (UTC)
If the patent includes scientific research references in the prior art section ... can that be used? Any response appreciated. J. D. Redding 18:31, 18 April 2008 (UTC)
Your point is a fair one: a patent is a good source for the description of an invention. It is however, as we almost all agree, a poor source for assertions about science. — BillCtalk 17:30, 18 April 2008 (UTC)
Editors should include patents in article over people?
Editors should include patents in article over devices?
Editors should include patents in article over scientific concepts?
I would take the above to mean yes on 1 and 2 and no on 3. Is that right?
I doubt there is ever a requirement that editors should include a patent (or patents) in any article. However, for an invention, a patent can be useful in describing the invention and citing its date. I feel however that care should be exercised here. Many inventions are not the work of a single individual or single patent: television, for example, was a series of improvements upon a basic idea; it would be difficult and probably misleading to the reader for an editor cherry-pick individual patents. In articles about individuals, the case is less clear. Many inventors were prolific recipients of patents and to attempt list them all would create an unusable linkfarm. Even single patents are probably not very edifying about their inventors. In the final case, articles about scientific concepts, patents are near to useless: they are simply not reliable sources for science that is better reported elsewhere, e.g. in books. A patent for a radio receiver in an article about atmospheric electricity tells us nothing about atmospheric electricity, let alone very reliably. There are better sources.
So to reply to your question, I would give my answers as 1: usually not; 2: maybe, if appropriate; 3: almost certainly not. And to add to that, I'll say a list of patents is a bad idea under any circumstances. No-one will ever read them all, even if they are relevant. Regards, — BillCtalk 20:24, 18 April 2008 (UTC)
Over time (been several years now), I have seen several pages talking about the telluric currents and the patents. They should be reincluded. --J. D. Redding 04:35, 23 August 2011 (UTC)