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Good articleJet stream has been listed as one of the Natural sciences good articles under the good article criteria. If you can improve it further, please do so. If it no longer meets these criteria, you can reassess it.
Article milestones
DateProcessResult
May 13, 2008Good article nomineeListed

Discovered by Thaddeus Lowe?

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The article about Thaddeus Lowe says:

Thaddeus Sobieski Constantine (alt. Coulincourt) Lowe (1832–1913) was an American engineer. He was exactly 29 when he proposed the idea of observation balloons during the American Civil War. During the Civil War, he became the commander of the United States' First Balloon Corps division. He flew the Intrepid, one of six hot air balloons used during the Civil War in addition to the Enterprise. While doing so, he was captured as a spy in North Carolina. He later used his knowledge of balloons to discover the jet stream.

Actually I doubt that... - Alureiter 18:14, 11 November 2005 (UTC)[reply]

Child, you cut me to the Quick!

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A quote from the Wizard of Oz just before he took off in a balloon.

I never realized this question about Lowe and the Jet stream existed. In the biographies of Lowe, he is spoken of as having recognized a high wind above winds that always blew to the East. In his Cincinnati to Unionville South Carolina balloon flight, he flew a high wind, in excess of 18,000 feet, to that spot. If that's not the Jet Stream, then I'll redact. Maybe somebody named it "Jet Stream" later on. The best of aviators of the day, 1857-1859, realized that a transatlantic flight could be made by this wind, even though it was never accomplished. Lowe's subsequent period of Civil War ballooning had nothing to do with Jet Stream flight. Add to that, the best scientists from the Smithsonian, including Lowe's mentor Prof. Joseph Henry, were sold on Lowe's meteorological calculations, some of the earliest ever documented. I remain yours truly, editor of the Thaddeus Lowe article--Magi Media (talk) 01:15, 25 May 2008 (UTC)[reply]

Ooishi and Esperanto?

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The article says that Ooishi's work on the Jet Stream "went largely unnoticed outside of Japan as he chose to write in the international language of Esperanto which was little read in scientific circles."

And Japanese *was* widely read in scientific circles in the 1920s??? The way the matter is phrased to me seems boardering on being non-neutral towards Esperanto...

I don't think so - it would be true if he wrote it in any other language than those commonly used in international science circles (French and German for that era, I think, although I am very much uncertain of that). It's not a comment on Esperanto, it's a comment on the language used not being a language commonly used in scientific papers of the era. 69.162.59.13 14:31, 27 February 2006 (UTC)[reply]
In my rewrite I've addressed this. Esperanto was preferred by scientists like Ooishi whose native languages were unlikely to be read by Europeans. Unfortunately, the Europeans didn't get the message. ;-) After WW2 English became the scientific language of choice. --Dhartung | Talk 22:24, 7 June 2006 (UTC)[reply]

Fire balloons

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The article says:

"It was however utilised during World War II by the Japanese military in the fire balloon attacks on the American mainland (see below)."

But there is nothing below on the fire bombs :( 129.241.11.199 14:26, 17 March 2006 (UTC)[reply]

This is now hyperlinked to the article fire balloon Ma.rkus.nl 16:01, 21 August 2006 (UTC)[reply]

Factual error about Wiley Post

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"During World War II the American aviator Wiley Post.."

Wiley Post died in 1935. WWII started in 1939 and the U.S. entered the war in 1941. Clearly either the timeframe is wrong or it was not done by Wiley Post. MichaelSH 04:27, 27 May 2006 (UTC)[reply]

It's incorrect to write this as a competition between Ooishi and Post. Not even Ooishi fully understood what he had discovered, and the paper that was already linked to as the source did not overstate this, but its description here did. I've used that source to write a fuller history of the process of discovery that gives due credit to others including the German who first coined the term. --Dhartung | Talk 22:22, 7 June 2006 (UTC)[reply]
Thanks for clearing this up. The article now makes sense. MichaelSH 23:48, 10 June 2006 (UTC)[reply]

Fastest speed

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According to Guinness World Records 2006, a jet stream speed of 656 km/h (408 mph) was measured above South Uist December 13, 1967. More on the subject here.

The link cited is broken. Is the Guinness book a reliable source? if so can the article be revised, please? Jet stream of 300 mph has been reported on BBC TV news as causing prolonged periods of stormy weather in the UK, Jan-Feb 2014.Vernon White . . . Talk 00:53, 11 February 2014 (UTC)[reply]

Here's an another link on the subject with more details --Anshelm '77 (talk) 13:16, 4 July 2015 (UTC)[reply]

Tailwind caused a stall

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My comment refers to the Jet Stream article found at http://en.wikipedia.org/wiki/Jet_stream. The text in question is quoted here:

“A 1943 Royal Air Force raid on Gironde, France, encountered tailwinds that sped them to their target, but returning the same headwinds, estimated at 380 km/h, caused their aircraft to stall, and the crews were forced to parachute into occupied Vichy France, where they were captured.”

I’m having trouble with the suggestion that the same headwinds, on the return trip, caused the aircraft to stall. Airplanes fly within the air mass and as such have air speeds. It really doesn’t matter which direction the air mass is moving, the aircraft is transiting that air mass at an airspeed that will allow it to continue flying. If they somehow tried t slow the aircraft’s airspeed to provide a given ground speed, then it would be possible to slow the aircraft (airspeed) sufficiently to allow it to stall (a pretty dumb thing to do).

There is a phenomenon encountered by airplanes approaching airports for landing (low altitude, slow airspeed, & perhaps hanging numerous lift/drag devices such as flaps and landing gear) in which a headwind quickly changes to a tailwind effectively causing the airspeed to drop to critical levels (and possible the aircraft to crash). This “wind shear” effectively steals the lift from the wings and unless the pilot can return the airspeed to flying speed quickly, they will likely crash.

Even if the 1943 flight encountered such a wind shear at altitude, it should not have caused the aircraft to stall and the crew to abandon it. Altitude is your friend in these situations and the 1943 flight should have been able to trade altitude for airspeed sufficient to maintain controlled flight.

If I missed the point of the article, I apologize in advance. Please accept these thoughts in the spirit in which they were intended.

Thank you for an excellent article. — Preceding unsigned comment added by 70.188.252.180 (talk)

Removed the text since no citation was added, and the statement does sound quite unlikely to me. Kumiankka 22:12, 30 March 2007 (UTC)[reply]
The statement comes from the article on Ooishi in the External links section:
Flohn (1992, p. 13) [Oral history memoir]
An English bomber squadron encountered NNE headwinds of 380 km h−1 (~106 m s−1) on return from a raid over Gironde (west coast of France) in 1943. Crews parachute from stalled aircraft and are captured by German Army.
The source cited is a German memoir Flohn, H., 1992: Meteorologie im Übergang Erfahrungen und Errinerungern (1931–1991). Ferd Dümmlers, 81 pp. It is only a report, but it was included in the overview used to rewrite this article, so I thought it significant. Flohn being a meteorologist and not an aerospace engineer I don't think we can determine whether it's realistic or not, but it is sourced. --Dhartung | Talk 01:42, 31 March 2007 (UTC)[reply]
Wow. I'm surprised to see this aviation myth has even made it into print. The only logical explanation I can think of is them having run out of fuel if the headwind slowed their return enough, however it's not our place to speculate on that since that would be original research. However I suggest leaving the statement out as exceptional claims require exceptional sources (WP:CITE) Thanks for clarifying the matter :) Kumiankka 22:16, 4 April 2007 (UTC)[reply]
Keep in mind this may just be a mistranslation. I think "stalled" just as well implies the simpler case, that they ran out of fuel. The relevant point is that they encountered the extreme headwinds found only at those altitudes. Anyway, this has to have been documented elsewhere, so maybe we can find a better source. --Dhartung | Talk 05:29, 5 April 2007 (UTC)[reply]
I posted a question at the military aviation task force. Maybe somebody there has a suggestion. --Dhartung | Talk 05:40, 5 April 2007 (UTC)[reply]
I remember a TV program that talked about B-29 crews discovering that they were flying in very strong winds. The bomb sight calculated the wind from aircraft airspeed and an optical fix (a fixed point) on the ground. The reported wind speed was off the scale and the crew abandoned the mission. Fortunately they had an intelligence office on-board to vouch for the crew. The result was that the B-20 couldn't use this bomb sight for accurate bombing and was obliged to 'carpet' bomb. More on the subject here

The very first paragraph states, "Jet streams are fast flowing, relatively narrow air currents found in the atmosphere at around 11 kilometres (36,000 ft) above the surface of the Earth, just under the tropopause. They form at the boundaries of adjacent air masses with significant differences in temperature, such as of the polar region and the warmer air to the south. The jet stream is mainly found in the stratosphere."

Since the stratosphere is found above the tropopause and not just under it, where exactly is the jet stream found?!

This has been fixed. Thegreatdr (talk) 20:02, 8 May 2008 (UTC)[reply]

See also BOAC Flight 911

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  • BOAC flight 911 crashed after hitting severe Lee Wave Clear-air turbulence near Mt Fuji. This was a very sad accident. Clear-air turbulence is also encountered around jet streams, but this was not the case for Flight 911 (at just 4,900M) and so I have removed this link.--JollyTom 09:04, 24 August 2007 (UTC)

Like Birds?

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"In the Northern Hemisphere the streams are most commonly found between latitudes 30°N and 70°N for the polar jet stream (pilots remember that like birds they go north in the summer and south in the winter),"

What are we talking about here, do pilots go north in the summer and south in the winter, or does the jet stream. In my experiance the jetstream drops further to the south during the winter and gets pushed higher to the north during the summer. I could be... and probobly am... wrong though.

I worded the passage more appropriately. It was stated opposite to reality. Thegreatdr (talk) 20:01, 8 May 2008 (UTC)[reply]

Is there a way to harness energy from the Jet Stream to ease the strain?

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Harnessing energy from the constant currents of Jet Streams may be a solution to some of Human energy concerns. Perhaps there is a way to create nanotech instruments that can capture the currents power in the Tropopause. Sort of like Dams. —Preceding unsigned comment added by Mahovictor (talkcontribs) 04:56, 3 December 2007 (UTC)[reply]

I have added a section concerning this possibility. Thegreatdr (talk) 21:26, 8 May 2008 (UTC)[reply]

Do any birds/insects/creatures use the jet stream besides us? —Preceding unsigned comment added by 67.164.65.21 (talk) 03:17, 12 February 2008 (UTC)[reply]

The only means of doing this will always involve a tether: strong enough to withstand many tonnes of drag-force, but light enough (over 10's of km of [oblique] length) not to bring the whole thing down. The tethers (thousands of them to be practical) also must not pose an aeronautical hazard. These pose obstacles that would be practicably insurmountable. Furthermore, the jet streams are neither stable in horizontal or vertical position, nor strength. All those aerial wind-farms' kites could come crashing down with no wind to keep them lofted. JohndanR (talk) 18:33, 20 October 2020 (UTC)[reply]

Jetstream direction

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This article says jet streams flow from east to west. Other web pages dealing with jet streams say the opposite, that the winds flow from west to east.

This should be fixed now. Thegreatdr (talk) 21:40, 8 May 2008 (UTC)[reply]

Tropical or subtropical

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The article says "Northern Hemisphere (stream is) between latitude 20°N and 50°N for the subtropical (sic)". Should that last word be subtropical or tropical without the prefix "sub"? Moriori 02:27, Apr 9, 2004 (UTC)

Subtropical. Sorry for the very long delay. I'm surprised no one answered you sooner. Thegreatdr (talk) 17:06, 8 May 2008 (UTC)[reply]

Wiley Post

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article states that jet streams were discovered during WW II by Wiley Post. He actually died in 1935, but did discover them.

A user has corrected the discoverer. It was not him. Thegreatdr (talk) 17:10, 8 May 2008 (UTC)[reply]

ECMWF data

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I'm a bit puzzled as to how the page text and piccies fit in with pix like http://www.ecmwf.int/research/era/ERA-40_Atlas/images/full/D25_XS_DJF.gif. Obviously thats a long-term mean and doesn't take account of meandering, but... there is really only one jet per hemisphere... they are clearly far more than a few km wide... and so on William M. Connolley (talk) 20:11, 11 May 2008 (UTC)[reply]

If you average it out like that over 3 months, yeah, only one wind maximum shows up, and it is broad. That doesn't mean there's only one jet per hemisphere though and that it is a thousand or so km/miles wide. Of the sources I looked through (let alone personal experience) there are at least 2 main jet streams much of the time...the polar and subtropical...and usually the subtropical is only present in a couple pieces. The polar is prone to splitting into 2 or more pieces from time to time, in unphased flow. That graphic might be useful for the climate article though, if it were in the public domain (which it likely is not, being that the ECMWF is the source). Thegreatdr (talk) 21:10, 11 May 2008 (UTC)[reply]

GA nomination on hold

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GA review (see here for criteria)
  1. It is reasonably well written.
    a (prose): b (MoS):
  2. It is factually accurate and verifiable.
    a (references): b (citations to reliable sources): c (OR):
  3. It is broad in its coverage.
    a (major aspects): b (focused):
  4. It follows the neutral point of view policy.
    Fair representation without bias:
  5. It is stable.
    No edit wars etc.:
  6. It is illustrated by images, where possible and appropriate.
    a (images are tagged and non-free images have fair use rationales): b (appropriate use with suitable captions):
  7. Overall:
    Pass/Fail:

Overall, the article is almost there. Here's the things I saw:

  • There is a mention of the tropopause twice in the first paragraph of the lede. It is a little bit redundant to say the same thing twice—can it be condensed somehow?  Done Thegreatdr (talk) 12:46, 13 May 2008 (UTC)[reply]
  • In the Discovery section: what is a pilot balloon? A dirigible, or just a hot-air balloon?  Done Thegreatdr (talk) 12:54, 13 May 2008 (UTC)[reply]
  • A bit more detail about Rossby waves (e.g. that they're created by the Coriolis effect) would be helpful in the Description section. An extra short sentence or two would suffice.  Done Thegreatdr (talk) 13:08, 13 May 2008 (UTC)[reply]
  • "The CAT is strongest on the cold air side of the jet,[7] usually next to or just below the axis of the jet." - I'm confused by "below" here. Does that mean towards the equator? (I guess it makes sense for the Northern Hemisphere, but the directional analogy breaks down for the Southern Hemisphere.)
  • In the Cause section, the relationship between temperature and pressure is a bit diffuse for non-technical readers. However, I'm not sure whether that should be explained in depth in this article, or if that explanation belongs in another article. Maybe saying "If two air masses of different temperatures and densities meet, the resulting pressure difference (which causes wind) is highest within the transition zone." would be sufficient.
  • (Not for GA) - the atmospheric parcel description could be made more engaging by adding a picture of a control volume surrounding the atmospheric parcel.
  • What are the effects of El Niño / La Niña associated with the jet stream outside North America? (This is the primary reason I put the article on hold)
    • I found a reference mentioning that ENSO combined with PDO phase affects the jet stream over Europe. I also found a reference regarding El Nino and South America. North America definitely seems to be influenced most from ENSO, since it lies immediately downstream of the warming/cooling signals seen in the tropical Pacific and since it impacts during the Northern Hemisphere cold season. In searches for Australia, ENSO influences to not extend to the jet stream. Thegreatdr (talk) 14:42, 13 May 2008 (UTC)[reply]
  • A few more links in the ENSO section would work (e.g. Gulf coast, Southeast, Rockies, Sierra Nevada, etc.) I didn't do these because I'm running a bit out of time to review the article. Done Thegreatdr (talk) 13:20, 13 May 2008 (UTC)[reply]
  • Ref #2 needs to be formatted similar to the rest of them (and needs an accessdate too).
  • Fill out the work parameter for Ref #19, so people can know it comes from the AOML FAQ.  Done Thegreatdr (talk) 13:24, 13 May 2008 (UTC)[reply]

Again, it shouldn't require that much work to get the article to GA status. Titoxd(?!? - cool stuff) 23:51, 12 May 2008 (UTC)[reply]

Looks good. The only thing that I see now is that since the Forecasting section was split off, it is now a little bit short. Would it be appropriate to mention troughs and ridges in this section, or not? Titoxd(?!? - cool stuff) 20:56, 13 May 2008 (UTC)[reply]
I moved the short section to description. It looked out of place where it was initially anyhow. See if that looks better. Thegreatdr (talk) 21:03, 13 May 2008 (UTC)[reply]
Added refs for CAT mishaps. Thegreatdr (talk) 21:31, 13 May 2008 (UTC)[reply]
You edit-conflicted me when I was doing that, heh. It looks really good now, so I'll promote it. Titoxd(?!? - cool stuff) 21:33, 13 May 2008 (UTC)[reply]


Alternative JET STREAM theory

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The jet stream is caused by the rotation of the earth moving faster then the static air above the lower atmosphere]

There is a intermediate layer of stationary air [fisenne zone?] with sufficient viscosity to interact with the lower atmosphere. Simple inertia of this layer translates to an apparent high speed wind from the ground viewpoint. Theoretically, wind speed ranges from zero at the north and south poles to a thousand miles/hr at the equator. In fact, the strong heat thermals at the lower latitudes eliminate the static air. It is at the higher latitudes that the constant dynamic interaction of the lower atmosphere and the static air. creates the configuration called the jet stream.


Note:The tremendous power of the jet stream in an easterly direction cannot be fully explained in any other way: yet the powerless static air relies upon the earth's lower atmosphere to provide the apparent power.


My belief differs from conventional meteorology: but I am willing to bet a buck or two that I am correct. Submitted by Charles Fisenne 516-223-8899 2732 Park Ave. Baldwin N.Y. 11510 Replies welcome cfisenne@verizon.net —Preceding unsigned comment added by 72.89.100.3 (talk) 21:01, 6 January 2009 (UTC)[reply]

There are locations in the tropics that launch upper air balloons...which typically burst towards the 10 hPa level...or 100000 feet. Measured winds rarely reach 200 knots (370 km/h; 230 mph), let alone higher, and close to 40000 feet up that occurs offshore Japan and the eastern portion of North America (higher than jet level winds trail off.) I think the measured wind record aloft is on the order of 250 knots (290 mph). If what you are saying were true, those kinds of winds would have been measured as long as 60 years ago (if below 100k feet) or been detected in the drift of rockets/shuttles that have been launched since the 1930s. It's not a good idea to throw addresses or phone numbers on any of these pages, since there are copies of these pages kept (theoretically) forever. Thegreatdr (talk) 22:00, 6 January 2009 (UTC)[reply]

Left me scratching my head

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The article states:

"They are thought to be caused by a combination of atmospheric heating (by solar radiation and/or internal heat) and a planet's rotation on its own axis."

But if the jet stream moves in this direction, it would be moving faster than the earth is rotating. The article could use more depth on the jet stream cause? Ann arbor street (talk) 15:09, 8 June 2009 (UTC)[reply]

It is a combination of overturning (caused by heating) leading to polewards motion in the upper levels which then accelerates the air (by coriolis forces). The jet streams are the fastest bit of this; past that, it breaks up into instability William M. Connolley (talk) 20:03, 26 September 2009 (UTC)[reply]
I've just re-written the important bit, though I left a lot of (probably rather dubious) stuff behind William M. Connolley (talk) 20:46, 26 September 2009 (UTC)[reply]

I disagree with Boris over this [1] (we can leave the Coriolis aside for the moment). The fundamental *cause* is solar heating. Thunderstorms are just one mechanism - they might even be the most important, I don't know - but they aren't the cause William M. Connolley (talk) 08:16, 27 September 2009 (UTC)[reply]

The original wording was "Tropical air heated by solar radiation..." which is wrong; heating of the air by absorption of solar radiation is small, and tropical air is heated mainly by sensible and latent heat fluxes. Introducing the idea that the ultimate heat source is the sun would be fine. Short Brigade Harvester Boris (talk) 14:24, 27 September 2009 (UTC)[reply]
OK, I left out some of the connecting words of course... it is heated by solar radiation, but that radiation goes via the ground, mostly. Also, of course, there is the element of organisation: a lot of the ground is heated, but ascent only occurs in a limited zone William M. Connolley (talk) 18:19, 27 September 2009 (UTC)[reply]

polar night jet

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A small number of articles talk about a "polar night jet". This seems to be an additional type of jet which seems to be higher (stratosphere?) than the normal jet stream and to occur only in winter months in the relevant hemisphere (hence "polar night"). Should information on this topic be a different article or in a subsection of this article? Feline Hymnic (talk) 23:24, 25 September 2009 (UTC)[reply]

I've begun a section within this article. But I noticed that two sources, both cited in my new text, give very different values for the height: "80,000 feet" (BBC source) and "30 miles" (Alaska source). That seems to be a factor of two difference and clearly incompatible. Any experts out there able to resolve this? Feline Hymnic (talk) 17:52, 26 September 2009 (UTC)[reply]
You might find the pix at http://www.ecmwf.int/research/era/ERA-40/ERA-40_Atlas/docs/section_D25/parameter_zmzwsp.html help (in particular [2] for NH winter and [3] for SH winter). Mind you, those are zonally averaged. The SH winter max appears to be at about 2 hPa, and the NH above 1 hPa. 80,000 feet ~ 30km ~ 10 hPa, and 30 miles ~ 50 km ~ 1 hPa. So thats one down to the beeb. But Ian James's "Introduction to circulating atmospheres" (conveniently available from google books [4] (fig 9.5) would put the core at 0.1 hPa it looks to me, ~60 km William M. Connolley (talk) 19:59, 26 September 2009 (UTC)[reply]

Incidentally, I'm not really sure about the "polar jet" stuff in the article. Can you see the polar jet in, e.g., this [5]? William M. Connolley (talk) 20:23, 26 September 2009 (UTC)[reply]

Thanks. The ECMWF pictures are certainly colourful. But taking the perspective of a lay, non-meteorological, reader, what do they mean? I've tried to assemble the text from cited sources in a way that I (a non-met. person) could follow. But it could certainly do with revision, not least the apparent contradiction in altitudes. I get the feeling that the ordinary "polar jet" is reasonably tightly constrained in altitude to the tropopause (I think I now know roughly what that might be) which is itself reasonably tightly constrained in altitude (albeit varying with latitiude as per the picture in this article.) By contrast might the "polar night jet" appear at more or less any altitude (more or less unconstrained) in the stratosphere? Help, I'm struggling! Feline Hymnic (talk) 20:33, 26 September 2009 (UTC)[reply]
I don't think this is easy. The article sez Polar jet streams are typically located near the 250 hPa (7.38 inHg) pressure level, or 7 kilometres (4.3 mi) to 12 kilometres (7.5 mi) above sea level, while the weaker subtropical jet streams are much higher, between 10 kilometres (6.2 mi) and 16 kilometres (9.9 mi) above sea level. but the "much stronger" polar jets are very hard to reconcile with, e.g. [6] which is at their supposed strongest height of 250 hPa. But since the article links the PJ to the mostly-mythical Ferrel cell this isn't too surprising. This [7] makes it clear that the polar night jet is quite deep and doesn't have an easily-identifiable single altitude. Though those are both 40-year averages; a single year or day might well look different William M. Connolley (talk) 21:06, 26 September 2009 (UTC)[reply]

A decade+ later, and the 2:1 height discrepancy is still unexplained, standing out like a sore thumb to this reader. Frankly, I find the first two references extremely weak (brief mentions in the popular press), and in the third it's a barely off-hand comment in an article on a different topic. Surely better references are available ... and if not, the section should be deleted. (Not me tonight.) Paleolith (talk) 23:20, 27 January 2024 (UTC)[reply]

Planets

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Lede sez "Jet streams, or just jets in context, are fast flowing, narrow air currents found in the atmosphere of planets at the tropopause, the transition between the troposphere (where temperature decreases with height) and the stratosphere (where temperature increases with height)." (emphasis added) Which planets other than Earth have a troposphere with a stratosphere above? Since the lapse rate reversal in the stratosphere is mainly caused by ozone absorption of UV, I'm curious as to whether this generalizes to other planets. Short Brigade Harvester Boris (talk) 21:05, 26 September 2009 (UTC)[reply]

upper-level and lower-level

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Having done a little recent editing in an attempt to improve the article, it still doesn't seem right to me (a non-met. person who is trying to gain an understanding of the topic). I think that one of the problems is that it still lacks some structure and, indeed, focus; and that one of the reasons for this is that it has (I think) ended up covering two different topics without realising it. The major topic seems to be "jet streams" (global weather systems? polar and subtropical? Ooishi (1920s)? WW2? commercial aircraft? etc.) The other seems to be more localised phenomena (barrier jet? African, Australian winds? etc.) My guess is that these two topics are really largely different (perhaps a little overlap) but that happen to share a common name "jet".

Might it help it if we consider splitting this article into two separate ones? Presumably the global weather article (polar, subtropical etc.) would retain the title "jet stream". What might the other be called?

Just a thought. Feline Hymnic (talk) 20:22, 27 September 2009 (UTC)[reply]

A jet is just a maximum of wind. It could be low level or upper level. Since both are considered jets, they both belong in the article, even if they're caused by different processes. Thegreatdr (talk) 13:45, 24 October 2009 (UTC)[reply]
Indeed. And thanks for your reply. I think the distinction, now becoming clearer (to me as a non-met. lay-reader), is a terminological one, between 'jet stream' and 'jet'. It seems that the term 'jet stream' specifically refers to the polar and sub-tropical jets (maybe also other upper-level jets, perhaps?) whereas 'jet' is a more general term describing both the principle of all jets and as a over-arching term to accommodate the known instances (both upper-level 'jet streams' and the various lower-level phenomena).
Try skim-reading the article, without getting too immersed in detail, and at each paragraph ask the question: Is what is being described in this paragraph a 'jet-stream' (global polar/sub-tropical etc.) or one of the other 'jets'?. This distinction isn't always clear; it is for that reason I'm proposing a split of the article. (Of course, if we can make this single article clearer to the lay-reader, that would be fine.) Feline Hymnic (talk) 16:09, 24 October 2009 (UTC)[reply]

The term "Coastal Low-Level Jets"[8] does not seem to be covered in the article. Here are some general scientific sources : Global Climatology of the Coastal Low-Level Wind Jets using different Reanalysis, Global View of Coastal Low-Level Wind Jets, Mesoscale modeling of coastal low-level jets. There are also several site-specific sources. TGCP (talk) 21:52, 29 August 2020 (UTC)[reply]

Origin of the name "jet stream"

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Jet streams may have been known for a long time, but I'd always understood that the term "jet stream" was only coined in the 1950s when jet passenger aircraft flying at altitudes of 30,000ft and higher started to encounter them regularly on the trans-Atlantic crossing. Can anyone shed some light on this? --Recoloniser (talk) 11:52, 3 January 2010 (UTC)[reply]

The answer is in the first numbered subsection "Discovery". (Jetstram translates litarally from "Strahlströmung"). Interestingly, German Wikipedia says the term Jetstream dates from 1944. Marc1966 (talk) 09:47, 22 February 2010 (UTC)[reply]

What is the 2nd reason for narrow jets

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Jet stream#Cause says "There are two factors that contribute to this sharpness of the jets. One is the tendency for developing cyclonic disturbances in midlatitudes to form fronts — sharp localized gradients in temperature." but doesn't say what the 2nd factor is (or provide a source). Rod57 (talk) 18:58, 10 January 2010 (UTC)[reply]

The article was rearranged 2 years ago after GA passage. The second factor is still there, it was just not labeled as such. I added in the wording to clarify the situation. Thegreatdr (talk) 04:27, 17 April 2010 (UTC)[reply]

First discovery?

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The article credits a Japanese scientist for first noticing the phenomenon, but this evening's PBS NewsHour has a piece that makes it earlier and links it to following the spectacular sunsets that followed the Krakatoa explosion in 1883. They interviewed a person who had written a book about this.

It is probably worthwhile looking into this. Bill Jefferys (talk) 22:57, 16 April 2010 (UTC)[reply]

Looks like someone just added it. Thegreatdr (talk) 04:28, 17 April 2010 (UTC)[reply]

Origin of the term

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A number of pop and news articles say something to the effect that Seilkopf invented the term "jet stream", and this claim found its way into wikipedia. Notice that the cite given (on the left pane) says nothing like this. Early German books typically write about Seilkopf's term, like, " 'Strahlströmung', English term 'jet stream'". The modern German synonym is "Starhlstrom".

By the way, please do not remove red linking from articles: a red link is useful: it brings an attention to the fact that an article is missing.

P.S. This leaves the issue open: who actually was first to use the English term "jet stream": was it just a translation of the German term or was introduced independently?

P.P.S. I understand that this may look like nitpicking, but for me it looks rather weird that a German is credited with coining an English word. It could make sense if the word was "international", e.g., "Agoraphobia" or directly borrowed, like Blitzkrieg, but here we have that a German term was translated, not borrowed. Therefore I rephrased the text in a more cautious way.

Jet streak

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Various articles refer to something called a "jet streak". This would appear to be some sort of component within a jet stream that moves even faster. Somewhere within Wikipedia we could do with a description of a "jet streak". Should it be a separate article or a section within this article? ANy volunteers? Feline Hymnic (talk) 23:02, 18 June 2010 (UTC)[reply]

A jet streak is an absolute wind maximum within the jet stream. If someone wished to start an article on it, I wouldn't mind. If you'd like to, be bold and do so. Thegreatdr (talk) 17:21, 20 June 2010 (UTC)[reply]

I came here to ask about what a jet streak is. NWS has an old, poorly maintained article [9] that I cannot understand. It would great if this topic were even mentioned in this article, but I think it deserves its own section. JKeck (talk) 14:35, 21 January 2021 (UTC)[reply]

Air needs to catch up?

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The introduction includes "Thus there is a tendency for air at higher levels of the atmosphere to "slip" and fall behind the speed of the air below. This results in a pressure buildup behind the "slipped" air, and so some air will have to catch up by moving in the same general direction as the planet's rotation (west to east on Earth)"

This makes no sense to me - on the face of it there is no obvious reason why a band of air in the upper atmosphere should not travel more slowly than the air above it. Surely the reason that the jet streams travel faster than the air below them is much more to do with equatorial air moving polewards while maintaining its angular momentum? In any case the statement needs a citation. —Preceding unsigned comment added by Majurawombat (talkcontribs) 04:45, 17 October 2010 (UTC)[reply]

Is AIUr Relevant?

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The first line of the article states: "Jet streams are fast flowing, narrow air currents found in the atmospheres of some planets, including Earth. "

Do planets other than Earth have air?

If not should the word air be either replaced to use some other generic term such as as "fluid"?

Or if air is a requirement for a jetstream, then perhaps the first like could become something like: "Jet streams are fast flowing, narrow air currents found in the atmospheres of Earth , and possibly some other planets."

I'm not a chemist, physicist or astronomer, but I was under the impression that air was pretty much taken to be the the stuff that surrouds us on Earth and that it was not known to be present elsewhere. — Preceding unsigned comment added by 14.2.35.175 (talk) 06:04, 24 June 2012 (UTC)[reply]

Cause or effect

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There is a tendency for the jet stream to be designated the cause or controller of surface weather. Should it be placed more as a consequence of the interaction between high pressure cells? In which case it is more of an indicator of surface weather. I am reminded of the ping-pong ball suspended on a vertical air stream. And also the air bubbles and debris gathered into a line on the surface between ebbing and flowing masses of water in a tidal estuary. 81.156.103.21 (talk) 10:52, 3 July 2012 (UTC)Jon Horridge[reply]

North American animation

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It seems a shame that the main animation in the lead shows jet streams over North America only. Span (talk) 22:12, 11 July 2012 (UTC)[reply]


Agreed. It would also be nice to have a bit more research/info on jet streams in the southern hemisphere. Latitude distribution, effects, map, and so on. FF FridayFields (talk) 03:32, 22 June 2015 (UTC)[reply]

a comment

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"aerial superhighway" that's not a "highway" — Preceding unsigned comment added by Guesters (talkcontribs) 18:42, 22 September 2012 (UTC)[reply]


Revisiting the "Alternative Jet Stream Theory" inquiry above

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Starting with the "Alternative Jet Stream Theory" heading above, and several other comments since then, I would like to add my concern about the stated origins or causes of the 4 main upper air Jet Streams (two in the northern hemisphere and two in the south). In both the opening remarks of the article, and under the heading "Cause" (subheading: "Other planets"), jet streams are said to be caused on other planets by "internal heating" - presumably nuclear reactions. The problem with this statement is that internal heating would cause the poles of the other (gas giant) planets to be as hot as their equators (compare with the sun). Thus the other statement, in the first section of "Cause", that the jet streams are the simple consequence of the equator being hotter than the poles, cannot be correct. Or, at least, there is an unexplained contradiction here.

Furthermore Uranus is unique among the planets because its axis of rotation is tilted sideways, nearly into the plane of its revolution about the Sun. Its north and south poles therefore lie where most other planets have their equators. Yet the winds at the equator are retrograde, which means that they blow in the reverse direction to the planetary rotation. Wind speeds increase with the distance from the equator, reaching zero values near ±20° latitude, where the troposphere's temperature minimum is located. Closer to the poles, the winds shift to a prograde direction, flowing with Uranus's rotation. Wind speeds continue to increase reaching maxima at ±60° latitude before falling to zero at the poles. (Words copied and pasted from the Wikipedia article on Uranus)

This could have been a reasonably close description of the earth’s upper air winds, which implies that it highly unlikely that it is primarily solar insolation, and the consequent differences in temperature between the equator and the poles that cause the major features of the airflow in a planet’s atmosphere. Internal heating will also not explain Uranian weather, as explained above.

I am not a meteorologist, but have been doing some reading on the subject, and coming up against the same problem in all the texts I have consulted. I am therefore going to stick my neck out, and join some of the other commentators on this Talk page, and suggest that it is simply the earth’s (or other planet’s) rotation on its axis that accounts for most of the atmospheric circulation. If air at the equator is centrifuged away from the surface it will start moving round a greater circumference than at the surface and therefore seem to move “retrogradely”, or in a westward direction. At the tropopause it will spread north and southwards, but as it does so it will start going round ever decreasing circles (lines of latitude) and therefore gain ground-speed in an eastward direction (compare with Uranus’ atmosphere). If traced on a map these high level winds follow tracks that curve clockwise in the northern hemisphere and counter-clockwise in the south. They are prevented from returning to the equator by the continuous outflow of high altitude air from the equatorial region. Thus there is a build up of high altitude air moving in an eastward direction at high velocity: i.e. the '’subtropical jet streams’’ at about 30° N and S, associated with the subtropical high pressure zones at ground level around the globe.

I think I have said enough for an amateur on this subject. (Continuing in the same vein it is possible to explain most of the main features of the earth's air circulation - e.g. the equator-ward polar easterlies, the mid-latitudinal westerlies, etc.) If what I have said above is physical nonsense then any further elaboration is going to be pure absurdity. I have only put it out there because I think the explanation for the jet streams, presented in the article, does not take into account the airflow patterns that have been discovered on the other planets, where the difference in solar heating of the equatorial regions exceeding that of the poles does not apply. Heating from within the planet is clearly not the driving force either. The only thing that all the planets have in common and could be responsible the similarities in weather patterns is their rotation on their axes. Whether or not this provides a complete and satisfactory explanation of the jet streams on earth and the other planets should be acknowledged as a possibility, or a reason given why it is an absurd idea, and that the cause of the jet streams is still enigmatic. Oggmus (talk) 14:19, 9 November 2014 (UTC)[reply]

Jet stream over the UK

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It's only in the summer months that it's been consistently displaced to the south since 2007, and only in the vicinity of the UK (Eastern Europe has seen abnormally warm summers since those in the UK deteriorated). The article says the English Channel, but at times it's been down over the Bay of Biscay or even Iberia when it "normally" (pre 2007) would be north of Scotland. I've seen claims that melting Arctic ice is behind this, but that doesn't explain why it suddenly started in 2007. There was a run of unusually poor UK summers in the mid-1980s as well, but that only lasted 3 or 4 years. It did seem to be righting itself in June and July 2014, before suddenly going back to the post-2007 position in August (and remaining there during summer 2015 so far). One or two years of this would be normal climate variability, but eight does not seem right.

In winter the North Atlantic Oscillation is the key, and perhaps should be mentioned in the article. Since the 2007 summer shift it's varied in winter, unusually negative in 2009-2011 and very positive since late 2013. Walshie79 (talk) 23:32, 28 July 2015 (UTC)[reply]

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Polar night jet

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The section seems to contradict itself. For example, the first sentence says it only occurs in the winter; the second sentence says that it occurs at a higher altitude in the winter than in the summer. Is the polar night jet a separate phenomenon from the all-year polar jet, or a variation of it? ZFT (talk) 04:47, 18 December 2016 (UTC)[reply]

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Description Section

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In the article I read:

"Rossby waves are caused by changes in the Coriolis effect with latitude.[citation needed] Shortwave troughs, are smaller scale waves superimposed on the Rossby waves, with a scale of 1,000 to 4,000 kilometres (620–2,490 mi) long,[1] that move along through the flow pattern around large scale, or longwave, "ridges" and "troughs" within Rossby waves.[2]"

This text raises questions with me as to what the author(s) mean(s) to say exactly, and I suggest it be rewritten.

"Rossby waves are caused by changes in the Coriolis effect with latitude.[citation needed]"

  • Clear enough, in my view.

"Shortwave troughs, are smaller scale waves superimposed on the Rossby waves, with a scale of 1,000 to 4,000 kilometres (620–2,490 mi) long,[3] that move along through the flow pattern around large scale, or longwave, "ridges" and "troughs" within Rossby waves.[4]"

  • Which waves have a scale of 1000 to 4000 km, the Rossby waves or the short waves?
  • Are the "large scale, or longwave, "ridges" and "troughs"" components / parts of the Rossby waves, or are they distinct from (and superimposed on) Rossby waves?
  • I.e. is a three-way division of 1) Rossby waves, 2) large scale, or long wave, "ridges" and "troughs", and 3) shortwave troughs, with successive or recursive superimposition, meant here?

If my understanding is right, I would suggest the following wording.

"Rossby waves are caused by changes in the Coriolis effect with latitude.[citation needed] Superimposed on the Rossby waves can be shortwave troughs, which are smaller waves with a scale of 1,000 to 4,000 kilometres (620–2,490 mi) long,[5] and which move along through the flow pattern around the large scale, or longwave, "ridges" and "troughs" that constitute the Rossby waves.[6]"Redav (talk) 16:15, 22 November 2018 (UTC)[reply]

References

  1. ^ Glossary of Meteorology. Cyclone wave. Archived 26 October 2006 at the Wayback Machine Retrieved on 13 May 2008.
  2. ^ Glossary of Meteorology. Short wave. Archived 9 June 2009 at the Wayback Machine Retrieved on 13 May 2008.
  3. ^ Glossary of Meteorology. Cyclone wave. Archived 26 October 2006 at the Wayback Machine Retrieved on 13 May 2008.
  4. ^ Glossary of Meteorology. Short wave. Archived 9 June 2009 at the Wayback Machine Retrieved on 13 May 2008.
  5. ^ Glossary of Meteorology. Cyclone wave. Archived 26 October 2006 at the Wayback Machine Retrieved on 13 May 2008.
  6. ^ Glossary of Meteorology. Short wave. Archived 9 June 2009 at the Wayback Machine Retrieved on 13 May 2008.

Subtropical Jet section has major issues

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Unreadable typos and contradictory statements abound. I'll try to come back to fix it later when I'm more well versed on the subject, but if someone could get to it before then that would be excellent. — Preceding unsigned comment added by Conkaeso (talkcontribs) 01:43, 13 March 2019 (UTC)[reply]

Why do the jet streams go east?

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Cross section of the subtropical and polar jet streams by latitude

It's not clear from the article why the jet streams go eastward. The surface winds north of 60° go towards the west, and the high-altitude winds north of 35° also go towards the west, according to the article Atmospheric circulation. From the diagram I have put here, I suppose that the explanation is that the polar jet stream is basic'ly just westerly surface winds from the Ferrel cell which have risen to a high altitude, whereas in the case of the subtropical jet stream, it's westerly high-altitude winds from the Hadley cell. Is that the explanation? Why then are the jet streams so much faster than the winds they are derived from? Eric Kvaalen (talk) 12:32, 2 September 2019 (UTC)[reply]

why?...

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Why this current always runs in the direction from west to east? And why in recent years it is from the USA where thanks to the jet stream they always have mild summers and very snowy winters (long duration of snow cover is beneficial for underground water levels), and in Europe "thanks to" it always has hot summers way above the norm (droughts) starting from practically rainless months like March and April and warm rainy winters? I sense some weather machinations on the part of the US, who then push such "clogged" weather ("clogged" omega-shaped jet stream) eastward across the Atlantic and into Europe. 188.164.151.106 (talk) 13:26, 3 March 2022 (UTC)[reply]

Short lead

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This article has too short a prefatory lead for its good article status. If someone can invest some time and effort into expanding it so it adumbrates more of the content occurring in body, that would be very instructive from a reader's perspective. Thank you, MBlaze Lightning (talk) 09:51, 21 May 2023 (UTC)[reply]

I agree. Some broad numbers very early on would be very useful to help the reader build a mental image of what jet streams are. For example, the thing that makes jet streams notable is the high wind speeds, but it isn't until near the end of the 4th section (Description) that we get told what the typical and highest jet stream speeds are. Similarly for the dimensions of jet streams. At the start of the overview we get told heights, but no speeds. I think that something like the following needs to be in the lead or the Overview section. I hesitate to do it myself because I don't know much about this subject and am not sure how to deal with referencing.
"On Earth, jet streams occur between 7 to 16 kilometres (23,000 to 52,000 ft) above sea level. The width of a jet stream is typically a few hundred kilometres or miles and its vertical thickness often less than five kilometres (16,000 feet). The wind speeds often exceed 92 km/h (50 kn; 57 mph), and speeds of 400 km/h (220 kn; 250 mph) have been measured."
Macboff (talk) 12:28, 1 July 2024 (UTC)[reply]

Incorrect citation regarding Japanese biological warfare during ww2

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I've no idea how to edit so I'll just drop this here. The citation for Japanese ww2 biological warfare and cowpox production leads to an irrelevant list-style article about samurai warrior clans. 2604:3D09:3E7B:A600:40F:E464:1996:4594 (talk) 08:55, 14 December 2023 (UTC)[reply]

Link? Might be a usurped domain. Easy to fix once we figure out which it is. –Novem Linguae (talk) 09:23, 14 December 2023 (UTC)[reply]
Not usurped, but it's a website which seems to provide an infinite scroll of articles and the URL changes as one scrolls, so it's easy to grab an URL that doesn't work. One relevant article on that site is https://www.warhistoryonline.com/world-war-ii/operation-cherry-blossoms-at-night.html. However, that article mentions nothing about balloons -- it's about a potential (scrapped) biological attack using subs and gliders. Another article on the site, more likely the one intended as a reference, is https://www.warhistoryonline.com/world-war-ii/japan-set-us-west-coast-ablaze.html. There's a short paragraph about the possibility of using balloons to carry viruses, which was scrapped due to the danger of the balloons releasing their payload over Japan. The article seems sloppy -- that's where the mention of cowpox comes from, the author apparently not knowing the difference between smallpox and cowpox.
So I declare it an unreliable reference, and I will delete that part of the paragraph. The part about incendiary bombs is well known and much better documented, and is the main topic of the second link above, though surely there are much better refs. Including five sentences about the discarded idea of adding biological weapons to the balloons seems out of place in an article about jet streams.
The final two references are in Japanese and are not online, and appear to be linked to only the scrapping of the idea.
The remaining reference, about the incendiary balloon attacks, is OK, though its reference is an article by John McPhee in The New Yorker, which should probably be cited. I'll try to add it. Paleolith (talk) 00:13, 28 January 2024 (UTC)[reply]
I added the reference, and added a sentence derived from it.Paleolith (talk) 02:56, 28 January 2024 (UTC)[reply]

GA concerns

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I am concerned that this article no longer meets the good article criteria. Some of my concerns are outlined below:

  • There are several uncited paragraphs throughout the article, including entire paragraphs.
  • The lead does not summarise all major aspects of the article.

Is anyone interested in addressing the above concerns, or should this go to WP:GAR? Z1720 (talk) 02:45, 27 October 2024 (UTC)[reply]