#Edit this page Wikipedia (en) copyright Wikipedia Atom feed Talk:Lightning From Wikipedia, the free encyclopedia Jump to: navigation, search This is the talk page for discussing improvements to the Lightning article. * This is not a forum for general discussion of the article's subject. * Put new text under old text. Click here to start a new topic. * Please sign and date your posts by typing four tildes (~~~~). * New to Wikipedia? Welcome! Ask questions, get answers. * Be polite, and welcoming to new users * Assume good faith * Avoid personal attacks * For disputes, seek dispute resolution Article policies * No original research * Neutral point of view * Verifiability __________________________________________________ Search archives Former good article nominee Lightning was one of the good article nominees, but did not meet the good article criteria at the time. There are suggestions below for improving the article. Once these issues have been addressed, the article can be renominated. Editors may also seek a reassessment of the decision if they believe there was a mistake. Article milestones Date Process Result October 31, 2005 Peer review Reviewed October 16, 2006 Good article nominee Not listed Current Status: Former good article nominee This article is of interest to multiple WikiProjects. Click [show] for further details. WikiProject Physics (Rated B-class, Mid-importance) PhysicsWikipedia:WikiProject PhysicsTemplate:WikiProject Physicsphysics articles WikiProject icon Portal icon Physics portal * v * t * e This article is within the scope of WikiProject Physics, a collaborative effort to improve the coverage of Physics on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks. B-Class article B This article has been rated as B-Class on the project's quality scale. Mid This article has been rated as Mid-importance on the project's importance scale. WikiProject Severe weather (Rated C-class, Top-importance) Severe weatherWikipedia:WikiProject Severe weatherTemplate:WikiProject Severe weathersevere weather articles WikiProject icon Portal icon Weather portal * v * t * e This article is within the scope of WikiProject Severe weather, a collaborative effort to improve the coverage of severe weather on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks. C-Class article C This article has been rated as C-Class on the project's quality scale. Top This article has been rated as Top-importance on the project's importance scale. Crystal 128 energy.png Information from Lightning (or a previous version of it) is being actively used in the pool of 'Did you know?' facts on the Energy Portal. Article Creation and Improvement Drive Lightning was the Article Collaboration and Improvement Drive for the week starting Wednesday, 24 June 2009. For more details, see the Article Collaboration and Improvement Drive history. Archives Archive 1 Archive 2 ______________________ Search Threads older than 100 days may be archived by MiszaBot I. Please add new comments at the bottom of this page Contents * 1 I am this article's reckoning + 1.1 Section to be merged (if useful) o 1.1.1 "A typical lightning strike" * 2 Simply Summary for all questions regarding direction of flow of cahrges * 3 Flash * 4 Proposal to Merge Articles * 5 Dark Lightning * 6 Reworking this article with regards to Cloud to Ground lightning formation + 6.1 Terminology of Lightning - Word choice makes a difference, please observe * 7 Sections 1, 2 & 3 Cleanup, Revisions & Additions [edit] I am this article's reckoning There's so much clutter that the only way to save this article is to [DEL: burn it to the ground :DEL] split most of its content into daughter articles per Wikipedia:Summary style. I also intend to clarify the roles of the Thunderbolt and Lightning strike articles. More to come! Melchoir (talk) 08:32, 9 August 2012 (UTC) I've done a precis of the lead - only a draft but I think it's at least readable. Of course if you/others change the article then the lead will need revisiting. Good luck Chiswick Chap (talk) 13:11, 23 September 2012 (UTC) [edit] Section to be merged (if useful) The following section was tagged as disputed and overlapping too much with the rest of the article. I've therefore moved it here. If you find anything in it you want to merge into other sections of the article, please go ahead and do that. Chiswick Chap (talk) 19:11, 23 September 2012 (UTC) [edit] "A typical lightning strike" This article's factual accuracy is disputed. Please help to ensure that disputed statements are reliably sourced. See the relevant discussion on the talk page. (August 2012) This section duplicates, in whole or part, the scope of other article(s) or section(s). Please discuss this issue on the talk page and conform with Wikipedia's Manual of Style by replacing the section with a link and a summary of the repeated material, or by spinning off the repeated text into an article in its own right. Animation, based on high speed photography, depicting cloud to cloud lightning in Toulouse, France. The turbulent rising moist warm air flow combined with rain drops and ice crystals rising and falling though different temperature zones and electrical fields typical of cumulonimbus clouds may cause different parts of the cloud to accumulate an excess of positive or negative charge. Usually the top of the cloud which may be as cold as -40°C (-40°F) is composed of small ice crystals charged positively with the middle of the cloud charged negative with a possible small zone at the base of the cloud of positive charge. A large accumulation of charge gives rise to strong electrical fields in the clouds and induces fields on the ground of the opposite polarity. Electric fields accelerate charged particles. +--------------------------------------------------------------------- -------------------------------+this is decent, but technical issues, particularly at the end.... no "fields are induced", rather the negative charged bottom induces a positive charge on the earth's surfaces... which establishes an electric field. I've addressed this in my changes in the new Cloud to Ground layout. Borealdreams (talk) 08:29, 20 January 2013 (UTC) Air is a great insulator but when this potential difference between either parts of a cloud charged differently or the cloud and ground exceed the local dielectric strength of air (about 2 to 3,000,000 volts/m (2 to 3 MV/m) a inside cloud (IC), cloud to cloud (CC), or cloud to ground (CG), a massive flow of electrons in a lightning stroke may be initiated. Paths in the air with higher electric fields or lower dielectric strength cause the electrons in a lightning strike to go though a tortuous path in the air, changing directions slightly or significantly every few centimeters or inches. +--------------------------------------------------------------------- -------------------------------+again technical wording issues... it's much more complex than this... you don't address the "pooling" process of the iconic channel that forms the stepped leaders. it's not just exceeding resistance of air... it does this over short distance, which you talk about in the second half. "stroke" is a technical term, not used correctly here... need to establish the ionic channel first. I've addresses this as well. Borealdreams (talk) 08:29, 20 January 2013 (UTC) Each major stroke of a lightning strike is usually about 50 m (150 ft) long and lasts about 1 to 2 microseconds with a pause of about 50 microseconds as more charge is accumulated before resuming another stroke in a slightly or significantly different direction. The front of a lightning strike is called a stepped leader and may split into many different paths--not all of them reach the ground giving rise to the phrase: forked lightning. The part of the stroke that reaches the ground nearly always carries most of the charge and is seen as the lightning bolt as electrons rush to the newly found highly conductive ionized air and low resistance path. In a typical cloud-to-ground strike, electrons descend from cloud base to ground.^[dubious - discuss] +--------------------------------------------------------------------- -------------------------------+again wording issues.... you're talking about the "legs" between pools of the ionic channel. "stroke" is the overall channel, once attachment & discharge occurs. Outside of the given numbers and time, which are correct, this is very poorly written as it confuses different parts of the process. addressed below Borealdreams (talk) 08:29, 20 January 2013 (UTC) Just before the strike leader reaches the ground, the charge in the step leader induces a huge electric potential in objects connected to the ground (some 10's of million volts), that brings up spikes of positive charge flow from high sharp objects, lightning rods, people, trees, etc., connected to the ground or water. After the descending and rising charge paths meet, massive amounts of charge flow in the 1 to 4 cm (.5 to 1.5 in) thick ionized channel of air centered in a lightning bolt channel--this massive flow of charged particles heats the air and gives the brightest part of a lightning strike. The stepped leader of a bolt of lightning may take on average about 20 milliseconds to reach the ground. Occasionally much longer lightning strokes occur which take more time. Once the downward and upward current flow impulses meet--a few metres or tens of metres above earth--a much more conductive connection is established between the cloud and the ground and the front edge of the return stroke electrons zip from the cloud at about 0.3-0.5 times the speed of light, c, on the highly ionized lightning stepped leader stroke path. Return currents may continue for several microseconds with three or more repeat strokes common. Subsequent lightning strokes following the ionized lightning channel are initiated by dart leaders.^[1] +--------------------------------------------------------------------- -------------------------------+again, you're not fully understanding the processes. values are correct, but not understanding streamer formation, attachment, and the discharge process. addressed below Borealdreams (talk) 08:29, 20 January 2013 (UTC) The return stroke with its much larger current flow produces the highly visible intense main lightning strike as it heats and ionizes the surrounding air in the lightning channel to about 30,000 degrees C (54,000 degrees F). This fast and massively heated ionized air in the lightning channel "explodes" creating the shock waves that within a few yards decay to loud sound waves we hear as thunder. Thunder, under ideal conditions, can be heard from over 20 km or 12 miles away. The relatively slow speed of sound (~340 m/s) and the extended length (5-6 km) of a typical lightning strike extends the sound of thunder over several seconds. +--------------------------------------------------------------------- -------------------------------+decent attempt... technical wording consistency is needed. use of words like plasma would help. It would be better approached by explaining the Discharge process... as it cycles back & forth (I believe the average is about 7 times) and further describe this. A second paragraph about "thunder" would then be wise, showing it is a result of the cycling discharge process. Also note, "rumbling" is not necessarily from this discharge cycling, it has more to do with the 3D nature of the stroke channel in relation to the person hearing it.... the strike termination might be 1 mile away, but the origin in the cloud may be 5 miles away... so the shockwave generated at each portion of the stroke channel reaches the person at different times. Borealdreams (talk) 08:29, 20 January 2013 (UTC) Multiple return strokes over the highly conductive ionized channel to different local charge locations about 0.5 km (0.3 mi) away from the original sources in the cloud may be needed to establish a larger volume of charge equilibrium. Sometimes return strokes take long enough to recur that they cause the lightning to flicker. A typical lightning flash has four return strokes spaced a few tens of milliseconds apart but over 30 return strokes have been observed. Although resolvable with high speed photography and other instruments a typical lightning strike occurs much faster than the human eye can see it so it appears as a single bright flash of lightning lasting a few tenths of a second.^[2] +--------------------------------------------------------------------- -------------------------------+decent, but again technical wording is substituted with ambiguous words that sound better for reading. "four return strokes" can't you substitute this with "4 cycles"? And then you use "a typical lightning strike", "a typical lightning flash" interchangeably, when flash is a technical term (is it not the entire process?) and then use "bright flash" in a non technical manner to describe it. See again, word choice matters. Borealdreams (talk) 08:29, 20 January 2013 (UTC) Dependent on the location and time of year about 5 to 10% of lightning is positive lightning that originates mainly in the "anvil" of cumulonimbus clouds near the top of the typical thunderstorm, where a high positive charge (electron deficient) often resides. "Positive lightning" that forms in this region has a descending stepped leader that will carry an apparent positive charge as electrons rush to the top of the cloud leaving positive charged molecules behind. When this "positive pulse" reaches the ground electrons will flow from the ground to cloud--the opposite of the usual electron flow. Positive lightning is particularly dangerous since it originates in the upper levels of a storm cloud several kilometers higher than a typical lightning strike.^[3] +--------------------------------------------------------------------- -------------------------------+I don't know if I'd try to describe the process again, other than noting it comes from higher in the cloud, is a much rarer occurrence, "charge" flow happens in the opposite direction as negative lightning. And although positive lightning is far more dangerous, and you mention this, but why just because it comes from higher is it more dangerous??? Borealdreams (talk) 08:29, 20 January 2013 (UTC) The amount of air the strike must "burn through" to reach the ground requires a much stronger electric field. The current flow is typically much stronger than a negative strike. Its flash duration is longer, and its peak charge and potential can be ten times greater than a negative strike; as much as 300,000 amperes and well over several billion volts. Positive lightning, though typically rarer, can be the dominate type of cloud-to-ground (CG) lightning during the winter months and in the last stages of a thunderstorm. Positive lightning typically strikes at the edge of a storm but can strike up to 10 km (6 mi) from a storm. The positively charged upper parts of the cumulonimbus cloud has been identified as a major source of the recently discovered sprites, elves, blue flashes and other lightning like phenomena observed well above the clouds, 30 to 95 km (20 to 60 mi) in altitude, well above the parent thunderstorm clouds which typically stop at about 15 km. High speed photographs of a lightning storm show the step wise development of lightning strikes.^[4] Stages of a thunderstorm's life. Most lightning usually occurs in the mature stage with positive lightning possible in the dissipating stage. An average bolt of negative lightning carries an electric current of about 30,000 to 100,000 amperes (30-100 kA) at a voltage of over a billion volts. The current in a lightning strike can raise the temperature of sand high enough to fuse the silica in it into glass channels known as fulgurites, which are normally hollow and can sometimes extend as much as several meters into the ground. Water in trees can be heated enough to cause them to explode and/or set the tree on fire--a leading cause of forest fires.^[5]^[6] +--------------------------------------------------------------------- -------------------------------+ the above are properties of lightning, which I agree are not addressed very well anywhere in the wikisphere but are important. these should be in their own section imho. Borealdreams (talk) 08:29, 20 January 2013 (UTC) The most lightning deaths occur to people exposed in an open field or on water where they are the highest local object and most likely to attract a lightning strike. Lightning hitting a tree with people under it is the second leading cause of lightning deaths. Isolated trees are typically the highest object around and attract lightning--the danger in a forest of trees is reduced. The safest places to be if lightning threatens are inside a building with metal plumbing and wiring which conduct the electricity away from you, or inside a metal-bodied and metal-roofed vehicle which acts as a faraday cage. Cars are usually safe because lightning induced current and voltage stay outside the metal surrounding the typical passenger compartment and do not penetrate inside--the skin effect that makes Faraday cages work. The rubber tires on a motorcycle, etc. or the fabric topped convertible offer no protection. If Lightning Roars Stay Indoors.^[7] +--------------------------------------------------------------------- -------------------------------+ this does not even address step potential, which kills more than direct lightning strikes themselves. do any of these sources dissect whether it was direct strike or step potential? Borealdreams (talk) 08:29, 20 January 2013 (UTC) The average peak power output of a single lightning stroke is about one trillion watts -- one terawatt (10^12 W), and the stroke lasts for about 30 to 90 microseconds. Most of the energy is dissipated in creating the ionized air channel and thunder.^[8] +--------------------------------------------------------------------- -------------------------------+ could be added to the "lightning properties" section. Also, "in creating the ionized air channel and thunder".... technically not right.... the stroke channel has already been created in the stepped leader formation. Thunder is the result of cycling discharge, so this does not dissipate energy, the discharge process DOES. The values are probabaly correct, but the understanding/description is not. Borealdreams (talk) 08:29, 20 January 2013 (UTC) * overall a decent attempt, but too many technical wording issues Borealdreams (talk) 08:29, 20 January 2013 (UTC) [edit] Simply Summary for all questions regarding direction of flow of cahrges Thunder can be caused either with 1."cloud positive and earth negative" 2."cloud negative and earth positive" 3."cloud positive and cloud negative" Most common are 1 and 3. the occurrence of 2 is very rare. The rest regarding direction of flow of charges and ions follows just like in a Cathode_ray_tube -- Preceding unsigned comment added by Gsravan4 (talk o contribs) 17:55, 24 August 2012 (UTC) +--------------------------------------------------------------------- -------------------------------+"Thunder" is caused by the collapsing ionic channel [plasma] during lightning discharge. All those choices are related to lightning, not thunder. "Current flows" is not correct either, as it flows back and forth in every lightning event, cycling.... and that is why lightning is described more in agreement with alternating current, than direct current.... so your relationships are off again, so I don't know if it has any similarities to cathode ray tube. Borealdreams (talk) 08:44, 20 January 2013 (UTC) [edit] Flash Is Flash and Lighning the same? -- Preceding unsigned comment added by 91.17.255.110 (talk) 22:26, 3 November 2012 (UTC) No. Spirit469 (talk) 03:53, 3 January 2013 (UTC) +--------------------------------------------------------------------- -------------------------------+ not very helpful of an answer. :( there are words used by the general public to describe lightning, and then there are specific uses of the words used in the discussion of lightning from a scientific standpoint to describe the different processes.... unfortunately, they are often used interchangeably without understanding of their differences. I have thought about putting together a glossary of terminology related to lightning, but it quickly got ix-nayed when I proposed it for an AfC. Borealdreams (talk) 08:50, 20 January 2013 (UTC) [edit] Proposal to Merge Articles This is messy, and the topic has branched into 3 different pages. I propose to merge content from 2 pages, Lightning strike and Thunderbolt, into this one. After that, we can work on improving the overall quality of our coverage of this topic, and clean up the sources. Spirit469 (talk) 08:57, 3 January 2013 (UTC) Disagree - cleanup and maybe split. the Thunderbolt is based on a theological reference of which all others are derived.--Degen Earthfast (talk) 21:38, 5 January 2013 (UTC) Lightning strike could perhaps be merged here although it's pretty long - this article doesn't talk about strikes much at all, suprisingly. Thunderbolt should stay where it is, as it's more about the symbolic depcition of lightning than the actual phenomenon. --Wtshymanski (talk) 14:50, 9 January 2013 (UTC) I also agree that maybe lightning strike could be merged with this lightning article. The thunderbolt article appears to be at least partly non-meteorologically based, so I would leave that article separate (with appropriate links between that article & this lightning article here of course). Guy1890 (talk) 07:20, 27 January 2013 (UTC) * Agree with merge completely. Utter redundancy between the three. Shadowjams (talk) 18:39, 29 January 2013 (UTC) * Disagree with merge for good reasons Can we hold off on the across the board merge, noting the revisions, edits & additions I have made to the lightning page??? I believe "lightning strike" has a stand alone place now as a significant factor when it comes to man, man-made objects and CG/GC lightning to Earth, however it is a subset of the overall phenomenon of lightning itself. I have removed many instances of the word "strike" erroneously used to describe the overall event of a lightning "flash", and see the importance of maintaining this to differentiate between much more common IC & CC lightning and ground based interaction of CG/GC where the word "strike" has contextual meaning. Overall, just looking at "Lightning Strike" briefly, it is in pretty good shape, and could use some minor revisions allowing for it to maintain its stand alone status. Thanks! Borealdreams (talk) 18:39, 15 March 2013 (UTC) [edit] Dark Lightning https://www.youtube.com/watch?v=OBOolkHVG_Q . Just want to share this. Could be merged into the article as subsection. --McZusatz (talk) 19:38, 7 January 2013 (UTC) [edit] Reworking this article with regards to Cloud to Ground lightning formation Lightning#Development_of_Cloud_to_Ground_Lightning - There was decent info in here originally, but much was missing, and technical wording, as pertains to the study of lightning was inserted and maintained....words do have specific meanings, so please refrain from using editorial license in word choice for readability. I really don't want to get involved with other aspects of this page, however I know with a high level of accuracy from direct experience with the subject matter and an extensive amount of research into it. Thanks & more than willing to debate on technical merits. PS there are some minor typos, etc., but I don't have time to address right now, but soon will. Borealdreams (talk) 07:25, 20 January 2013 (UTC) The section is a good start, but it really needs more references to reliable secondary sources. Titoxd^(?!? - cool stuff) 18:01, 20 January 2013 (UTC) Thank you, & I agree. I wrote/edited it last night off the cuff, but I know it is "source-able", given it is technically accurate & I'm open to anyone interested in assisting. My comfort level (technically) is only in Cloud to Ground, channel formation & the process of a "bolt of lightning", but that carries thru to all the other types as well. I'm going to add in the next section, "A Glossary of Lightning Related Terminology"... that is partial, but also accurate. I believe, with following these "standards" instead of using "editorial license for word choice", it can greatly improve the quality of this article. Borealdreams (talk) 19:55, 20 January 2013 (UTC) [edit] Terminology of Lightning - Word choice makes a difference, please observe This is a glossary to help readers AND editors of Wikipedia understand the complexities of lightning important to the field of lightning protection systems. I welcome additions, corrections, etc., it's a work in progress, but it's important given so many technical words are ambiguous with general words associated with lightning. :) Borealdreams (talk) 20:12, 20 January 2013 (UTC) * Air Terminal - A class of devices of various manufacturing and design whose primary function is to be the preferred termination point of a lightning stroke. Lightning rods are an air terminal. * Atmospheric Transient - The spatial neutralization of charges on the cloud and ground surfaces during a lightning discharge results in a near instantaneous collapse of the slowly developed, previously existent electric field. This rapid variation in the electric field inducts a momentary electric current in any conductive object within this space, that can travel outward far beyond where the field collapsed, causing damage to any electrical equipment incapable of handling the surge. * Attachment - The process by which any downward leader "connects" to any available upward streamer. This process is not fully understood, but much research is dedicated to understanding it more fully. * Conductor - Any [generally] metallic object that can be energized to transfer electricity. Wires are primary examples of conductors, however under lightning conditions many objects; rocks, wood, can conduct the discharge as well. * Cloud-to-Ground (CG) - The primary form of lightning that effects mankind and enormous resources are both dedicated & spent in designing a protection from its effects. Ground-to-Cloud is also possible, but the process is similar to CG. Detailed discussion are probably not needed, given it is almost a reversal of CG. * Discharge - The neutralization of two oppositely charged areas when a conductive pathway has been established between them. On the small scale it is called a spark, on the large it is what we commonly know as lightning. In relation to lightning, the conductive pathway through the air is an invisible channel composed of ions, a form of plasma. * Dissipation - The act of dispersing a concentrated substance, i.e., smoke, heat, charge. It is often used interchangeably in contradiction to itself within LPS discussions. + Dissipate a strike termination - Providing a direct path to ground where the enormous amount of energy can be dispersed to earth in a very short period of time. (Air to the ground)... ground grids & ground rods provide a contact to the "dirt" of the earth... the larger the surface area, the lower the effective resistance. Although, too much can be "wasteful" as each has a zone of influence & they may overlap, reducing their cost to effect efficiency. + Dissipation of surface charge - The slow release of induced charge on a surface through point ionization in an electric field. (Ground to air) * Earth Current Transient - The surface charge that rushes through the Earth towards the termination point during the lightning discharge, commonly referred to as ground current, results in electric field fluctuation across any buried conductors; cables, wires or metallic pipes. As with atmospheric transients, these voltage surges can cause damages to unprotected electrical devices attached to either end of the subsurface conductors. The ground current that occurs during the discharge process is responsible for more injuries or death than direct lightning strikes themselves.^[9] * Flash - Total discharge of a Cloud-to-Ground lightning event, often composed of multiple strokes that may complete equalization at different physical locations.^[10] * Flash Density - Scientific recording of lightning strokes & flashes using satellites and ground based detectors. * Franklin System - A common name in the industry for a lightning protection system using lightning rods for air terminals. * Ground - As relates to electrical conductor's interface to Earth through an electrode. * Ground Rise Potential - When lightning terminates to earth it creates a spike in the empirical value of the local electric potential of the earth. This mechanism can have adverse effects on facilities that are physically far apart, with separated ground systems but are interconnected via signal and/or power cables. The spike in electric potential on the earth caused by lightning strike to one facility will cause the voltage potential the ground system to spike as well. Since the ground system of one facility is connected indirectly to the other facility's ground system through the signal and/or power wires, electricity will naturally flow from one ground system to the other in an attempt to equalize the electric potentials. The electric transient current flow through the unintended paths of the signal and/or power wires may cause damage to the electrical equipment along the way.^[11] Its affect may be referred to as earth potential rise and is similar in nature to man-made hazards (fault current) common to electrical substations. * Induction - The principle based on Faraday's Law of Induction that a conductor exposed to a moving magnetic field will experience voltage of varying but predictable degrees. In LPS, this may be the result of an atmospheric Electro-Magnetic Pulse (EMP) generated by a lightning flash or ground current passing by long lengths of conductors and creating a transient voltage, commonly referred to as a surge. * Isokeraunic Number - A mapping system similar to a topographic map used to represent the average number of strikes a given area, not a specific object, will receive in a year. The Democratic Republic of the Congo is the worldwide leader of strikes per area, in the United States, central Florida has the highest probability for lightning terminations.[1] * Lightning - In the industry, used commonly to discuss Cloud-to-Ground or Ground-to-Cloud strokes and flashes. Lightning protection systems are mostly used to protect physical structures on the Earth's surface, therefore discussion of other lightning forms, i.e., Cloud-to-Cloud or sprites are often not relevant. Airplanes and avionics being the notable exception. * Lightning ElectroMagnetic Pulse (LEMP) - The lightning stroke channel, with its very high magnitude currents that rapidly change direction in a very short period of time, is a concentrated, mainly linear flow of electrons similar to a high voltage transmission line. The near instantaneous dynamics results in a circular electric field being generated that follows the "right-hand rule", propagating outward from all the flash channels that can induce transients on any conductors it passes. [link to IEC:2010 62305-1 3.34] * Lightning Protection System - LPS for short, this covers all forms of systems used to protect structures and property. It is not exclusive to lightning rod systems only, and covers surge protection devices, grounding, charge transfer systems, etc. [link to IEC:2010 62305-1 3.41-2] * potential - The difference in oppositely charged areas across a space. Akin to a battery. Not to be confused with probabilities. * rolling sphere model - A "theory" derived through scientific research and trial & error, that appears to model effectively the behavior of lightning in the areas of termination. It is used to design lightning protection systems, of all forms, to protect buildings and property. Due to infinite variety of protected structures and the nature of lightning itself, the rolling sphere model has alluded the abilities of researchers to prove indisputably, however it is the accepted standard used in the industry for designing LPS^[12]. The Rolling Sphere Method is a geo-spacial representation used to model years of trial and error applications of air terminals as the preferred collection point. An expansion of the original concepts studied by Frankilin, the standards exemplified by the RSM are as equally based in scientific understanding of lightning as they are to outside influences such as insurance industry concerns about lightning-caused damages.^[13] * stepped leader, downward - It is an invisible channel composed of ions that forms from the clouds going towards the earth. Its intensity determines ultimately its route, however it acts relatively predictably by shooting out in one direction, pooling, shooting out again, 2nd pool, shooting out again, pool, repeat in so it takes on the appearance of steps. For simplicities' sake, it can be thought of as a wire hanging from the clouds, but not touching the earth. It is "searching" for a upward streamer, and once a connection is made, the flash is initiated. * streamer, upward - This is an ion channel that forms from the ground up, similar to Downward leader, however much smaller in size. It is often associated with originating from pointed objects that are exhibiting ionization, commonly referred to as st. elmo's fire. They are the "fingers" sticking into the air, hoping to make contact with a downward leader. Upon contact with a downward leader, a flash is initiated. * strike - Common nomenclature for a termination that consists of either strokes, flashes or both. * stroke - Electrical discharge components of a single lightning flash, it is characterized as a repetition of alternating upward and downward current flows until neutralization has occurred, and is responsible the visible pulsating effect seen in lightning.^[10] * surge protection device (SPD) - General & specific name for wide variety of products used to minimize the damage to electronics and electrical devices as a result of both direct termination and induced transient voltages within conductors. Lightning arrestors, data line protectors and transient voltage surge suppressors are all examples. * Termination - The physical location at which a lightning stroke makes contact with a solid object. Also referred to as a strike or lightning strike. * Thunderstorm - Is the atmospheric phenomena that is responsible for most Cloud-to-Ground lightning terminations. A thundercloud is a singular unit within the general thunderstorm system capable of producing lightning and is an understood reference point in scientific discussions. [edit] Sections 1, 2 & 3 Cleanup, Revisions & Additions I have done some major edits & cleanup of these 3 sections following Wikipedia:Be_bold's principle. Minus some minor typos, it is factually accurate, and there are a few "old lines" out of place that either need new homes for them found or removed all together. Please help me to source these changes versus reverting the edits, as they are out there and I will attempt to do so as well. I am working on reorganizing other areas as well, but running out of time. Thanks for your cooperation and input. :) Can someone add in a header note after the "contradictions/factual accuracy" drawing attention to revisions are currently under way, question accordingly. I know not how to do so. Borealdreams (talk) 18:22, 15 March 2013 (UTC) Cite error: There are tags on this page, but the references will not show without a {{Reflist}} template or a tag; see the help page. 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