Property talk:P2044

Documentation

elevation above sea level
height of the item (geographical object) as measured relative to sea level

Description

altura del elemento en relación al nivel del mar (es) – (Please translate this into English.)

Represents

height above mean sea level (Q6452016)

Data type

Quantity

Template parameter

"elevation_m" and "elevation_ft" in en:template:infobox settlement

Domain

According to this template: geographic location (Q2221906) (place)

According to statements in the property:
geographic entity (Q27096213) or object (Q488383)

When possible, data should only be stored as statements

Allowed values

According to this template: height in meters or feet

According to statements in the property:
−160,000 ≤ 𝓧 ≤ 100,000

When possible, data should only be stored as statements

Allowed units

metre (Q11573), kilometre (Q828224), foot (Q3710) or nautical mile (Q93318)

Example

Maïdo (Q3303392) → 2,205 metre
Badwater Basin (Q799720) → −279 foot
Bern Airport (Q619845) → 510 metre
Baranagar (Q712504) → 12 metre
Olympus Mons (Q520) → 21,229 metre
Inaccessible Island (Q914225) → 0 metre
Inaccessible Island (Q914225) → 511 metre

Source

external reference, Wikipedia list article (either infobox or source) (note: this information should be moved to a property statement; use property source website for the property (P1896))

Tracking: same

no label (Q32085169)

Tracking: differences

no label (Q21158631)

Tracking: usage

Category:Pages using Wikidata property P2044 (Q20989797)

Tracking: local yes, WD no

Category:Elevation above sea level not in Wikidata, but available on Wikipedia (Q21158632)

determination method (P459) values[edit]

This is a list of values used with the qualifier determination method (P459)

Manually update list

This list is periodically updated by a bot. Manual changes to the list will be removed on the next update!

WDQS | PetScan | TABernacle | Find images | Recent changes

#	qid	label	count	instance of	subclass of
1	Q1398875	Normalhöhennull	717	stream gauge sea level zero-level elevation
2	Q268449	Normalnull	349	stream gauge sea level zero-level elevation height reference system
3	Q23202	metres above the Adriatic	239	stream gauge zero-level elevation sea level
4	Q694278	Metres above the Sea	114	stream gauge zero-level elevation
5	Q27700527	NGF - IGN69	25	geodetic reference system
6	Q10566338	Hong Kong Principal Datum	18
7	Q791801	estimation	9	process	finding technique procedure reasoning
8	Q3393392	highest point	8		maximum landform point geographic entity
9	Q816425	surveying	7	activity academic discipline	technique
10	Q16619392	National Aerial Orthophotography Plan	7	project procedure technique
11	Q6452016	height above mean sea level	6		altitude elevation
12	Q39825	census	5	recurring event specialty field of study	source of information population estimation data set census
13	Q12453	measurement	5	academic major	estimation
14	Q10578722	maximum	4	sourcing circumstance Wikipedia article covering multiple topics	extremity maxima and minima operation result
15	Q216526	topographic map	4	type of map	map
16	Q5727902	circa	4	sourcing circumstance
17	Q125465	sea level	3	zero-level elevation	zero-level elevation water level
18	Q37113960	estimate	3	sourcing circumstance technique	value
19	Q187631	mathematical interpolation	3	mathematical model	algorithm
20	Q10585806	minimum	2	sourcing circumstance	maxima and minima extremity
21	Q2796622	mean	2	type of statistic umbrella term sourcing circumstance	central tendency
22	Q202785	average	2		measured quantity value central tendency
23	Q39875001	measure	2		quality
24	Q18822	Global Positioning System	2	radionavigation-satellite service global navigation satellite system	avionics Positioning system
25	Q4271952	Amsterdam Ordnance Datum	2	sea level stream gauge zero-level elevation
26	Q1378197	European Terrestrial Reference System 1989	1	geodetic reference system spatial reference system
27	Q37221	diameter	1		line segment physical quantity length geometric property
28	Q112058035	GPS telemetry	1		telemetry
29	Q1024499	Conductivity, temperature, depth	1	measuring instrument technical standard
30	Q12013	Google Maps	1	website digital map web application web mapping
31	Q108473834	minimum legal water level	1		water level minimum
32	Q108473830	maximum legal water level	1		water level maximum
33	Q7053896	North American Vertical Datum of 1988	1	height reference system
34	Q483130	geographic information system	1	academic discipline specialty field of study	application information system technique
35	Q19033	arithmetic mean	1	type of statistic	mean Pythagorean mean generalized mean weighted mean quasi-arithmetic mean
36	Q93344	trigonometric function	1		transcendental function periodic function elementary function
37	Q965136	Shuttle Radar Topography Mission	1	space mission space instrument	digital elevation model
38	Q8084	trigonometry	1	area of mathematics	geometry
39	Q66010986	Earth Gravitational Model 1996	1	version, edition or translation	geopotential model
40	Q2658976	Barometrische Höhenmessung	1
41	Q6130762	Sociedad Asturiana de Estudios Económicos e Industriales	1	public enterprise
42	Q178954	Istituto geografico militare	1	national mapping agency institute
43	Q2924304	multibeam echosounder	1		sonar
44	Q31087168	European Vertical Reference System	1	height reference system
45	Q28652667	Geodätischen Grundnetzpunkt	1
46	Q108584697	direct measurement	1		measurement

This property is being used by:

Please notify projects that use this property before big changes (renaming, deletion, merge with another property, etc.)

Determination of level[edit]

Statements using that properties have to mention the reference point. I propose to use determination method (P459) as qualifier in order to provide that information. A constraint about the use of the qualifier is added but the list of values for that constraint should be provided.

I propose to use the reference points of the different countries (at least in Europe) as value for the qualifiers. Snipre (talk) 09:00, 10 September 2015 (UTC)[reply]

You already added it as a constraint, but failed to provide a single sample or valid statement .. not really optimal as approach. --- Jura 09:05, 10 September 2015 (UTC)[reply]

@Jura1: Please read until the end my comment: I did a proposition for qualifier value. And if I didn't fill the template it is just because I preferred to have some debate about what kind of value can be used because if the property for the qualifier is really well suited for the current case, the type of the value is more difficult to define. Next time try to be a little more helping by doing some proposition a little more constructive. Snipre (talk) 17:43, 10 September 2015 (UTC)[reply]

I think this should be changed back from “elevation above sea level” to more general “height”, with a qualifier to specify what the height is relative to (there’s no single “sea level”, dewiki lists 28 different standards). I proposed a new property for this qualifier, but I guess determination method (P459) could be used too. —Galaktos (talk) 10:33, 10 September 2015 (UTC)[reply]

Just wondering, how many dewiki elevations are not measured by the national standard (points on borders excluded)? --- Jura 10:55, 10 September 2015 (UTC)[reply]

I’m not an expert, but from reading dewiki it seems that Germany switched from Normalnull (Q268449) to Normalhöhennull (Q1398875) (which is apparently “the basis of” United European Levelling Net (Q15852105) in Germany) in 1992 (after the reunification; Eastern Germany apparently used something called SNN56/Höhennull, which doesn’t even have its own Wikidata item).

Most newly published maps are based on NHN, but apparently that conversion isn’t finished yet.

Anyways, it seems heights in dewiki templates usually include the reference height as HÖHE-BEZUG parameter (see full list of supported references on de:Vorlage:Höhe#Parameter, „2. Parameter“). —Galaktos (talk) 11:23, 10 September 2015 (UTC)[reply]

So try to be more constructive: Do we want to specify the origin by using as value for the qualifier

the place defined as the reference point (Marseille for France, Ajaccio for Corse, Ostende for Belgium, Chiyoda for Japan,...)
the national norm/reference used to describe the way to define the level (LN02 for Switzerland and Liechtenstein, Naparima 1955 for Trinidad and Tobago,...)

or something different ? Snipre (talk) 17:43, 10 September 2015 (UTC)[reply]

Whatever the source says, right? I suspect this will usually be a national norm/reference (if the source is some official publication), but generally it’s not Wikidata’s task to reinterpret a height given relative to some norm as relative to some reference point, or vice versa. Wikidata just states what’s in the reference. —Galaktos (talk) 22:19, 10 September 2015 (UTC)[reply]

The source is always important but the question is to know if we want to increase the data available in Wikidata in order to perform comparison for example. The source will provide that kind of information but when someone wants to do the comparison, he woudln't have the time to read all references to extract that information. The idea of this qualifier is to standardize the way this information is stored in Wikidata. Snipre (talk) 19:39, 13 September 2015 (UTC)[reply]

Well, again, I don’t think it’s Wikidata’s goal to standardize the content of the information stored – it only makes it accessible in a common format. For the same reason, we support non-Gregorian calendars, and allow non-SI units for quantities, even though we could convert these too.

There’s also the question of what level to convert to? How do you choose the “standard” sea level when there are lots of different standards (map for Europe), most of which probably don’t even cover the entire globe?

For simple uses, like “what’s the highest mountain in Chile?”, I don’t think a conversion is necessary – it’s fine if the reference level is just ignored, since the difference between object heights is probably much larger than the difference between the reference heights. But for those uses that do care about the exact value, we need to have the correct, unadulterated value. —Galaktos (talk) 11:11, 14 September 2015 (UTC)[reply]

I think we have a problem of understanding: the idea is not to do any conversion, the idea is to give an additional information about the reference used in the definition of the elevation in order to inform the reader that one meter above the sea in Spain isn't the same value in France. The difference is often small but can reach more than one meter depending the countries. If I compare the Mont-Blanc in France with the Mount Vesuvius in Italy, I can't use raw data, but I theoretically have to correct the values because the references are not the same. By indicating with a qualifier the reference for each elevation, we can call the attention of the data user to the reference difference. This is not a critical point but this is a typical information which adds value in a database because you can perform some correction automatically like the one we are doing by indicating the calendar with the date.

If we want to do that kind of addition we have to provide some "standard" in order to help people to structure similar data. If someone provides as qualifier of the Mont-Blanc elevation the reference point = 7th arrondissement of Marseille (Q259408) (place where the Marseille marigraph is located) and another one add Marseille marigraph (Q3296411) for the Mont Ventoux, it is impossible for the system to deduce that both elevations have the same reference. So the standardization here is just to indicate what kind of data (location, item representing the measure instrument, the legal text defining the instrument as reference for a country,...) the contributor has to provide. Nothing more, nothing less. Snipre (talk) 13:53, 14 September 2015 (UTC)[reply]

Oh, I see the misunderstanding now. Thank you. However, I think I don’t understand the situation in other countries yet.

In Germany, the reference is Normalhöhennull (Q1398875), which is an imagined, quasi-geoid reference surface. All heights above NHN are vertical distances to that virtual plane. It has a reference point in Neue St.-Alexander-Kirche (Q1533101) (a church somewhere in northeastern Germany), but heights aren’t relative to that reference point; they’re relative to the plane described by NHN. In Germany, it seems clear to me that the item for the qualifier would be Normalhöhennull (Q1398875), not one of its reference points. And I would have assumed that other countries have a similar reference plane that should be used.

I don’t know if it works the same way in France, though. There seems to be some EU thing, United European Levelling Net (Q15852105), but both items you mentioned seem to be something different, and less suitable for being the qualifier item. (I thought “Marseille marigraph” sounded promising until I looked up what a “marigraph” is :) ) So I’m not sure now how we should proceed… —Galaktos (talk) 14:16, 14 September 2015 (UTC)[reply]

Altitude[edit]

Bonjour, comment peut-on faire pour gérer l'altitude maximum et minimum pour les communes, nouvelles propriétés, lower and upperbound ou qualificateurs (lesquels) ... ? Merci à vous.----Pinof (talk) 21:25, 13 September 2015 (UTC)[reply]

@Pinof: C'est un problème récurrent: plusieurs propriétés spécialisées ou une propriété avec des qualificatifs ? Il n'y a pas de réponse définitive sur la question. Le plus simple est de proposer les 2 propriétés altitude max et altitude min et de voir ensuite ce que la communauté décide. Les propositions doivent faites en utilisant le modèle Property documentation (voir template:Property documentation) et sur la page suivante Wikidata:Property_proposal/Place#General. Snipre (talk) 09:50, 14 September 2015 (UTC)[reply]

Altitude of a city?[edit]

A bot has started to import the elevation of cities from the infoboxes in the English WP (see e.g. [[1]]). However, a city may cover several km² and include hills and valleys, so instead of a rather arbitrary mean value (is it a mean value over the whole area, the value at the "city center") we'd either need a new datatype "number range", or two new properties "maximum elevation" and "minimum elevation", or would need some good example how to encode this information with qualifiers. Ahoerstemeier (talk) 21:07, 27 September 2015 (UTC)[reply]

I don’t think we need a new data type for this, since the current “Quantity” type already stores a mean value, lower limit, and upper limit (though lower and upper limit are presented in the UI as a single “±X” deviation – I’m not sure if it’s currently possible to store a datum where the value isn’t in the middle of lower and upper limit). —Galaktos (talk) 21:50, 27 September 2015 (UTC)[reply]

The “±X” is for precision of the number, which is not the range of the value. Jeblad (talk) 13:23, 7 November 2017 (UTC)[reply]

Cities do not have altitude. Cities have elevation. Airplanes have altitude. Openlywhite (talk) 01:19, 25 August 2022 (UTC)[reply]

P518 (applies to part)[edit]

I have used as value for this property for rivers the items Q1233637 (river mouth) and Q7376362 (river source). --Molarus 05:08, 6 January 2017 (UTC)[reply]

Flight Height?[edit]

Is this property intended to be used as the flight height of an airplane? As such, it is used by e.g. Q15901049, Q15623287 and Q890198. Steak (talk) 14:58, 16 April 2017 (UTC)[reply]

I just found Property:P2254, so using P2044 for airplanes is wrong. Steak (talk) 10:44, 21 April 2017 (UTC)[reply]

Truncated values[edit]

I'm seeing 57 instances of elevation above sea level (P2044) set to -32768 metres. As that is the largest negative signed 16-bit integer, I'm guessing that whatever automated system is adding these truncated values is using just 16 bits for its integers. Could somebody have a word with User:Mr.Ibrahembot and anybody else who is screwing up these entries before we get any more garbage added, please? Also the reference added in each case says nothing that I can see about elevation above sea level, so I can see no means to supply a corrected value. Ping User:Mr. Ibrahem in case the bot notification doesn't get through.

If I'm wrong and this property is somehow constrained in its most negative value by design, then perhaps that is the issue that needs to be addressed. Either way, it makes the data with this property unreliable for use elsewhere, especially with a false sourcing claim. --RexxS (talk) 20:07, 28 October 2018 (UTC)[reply]

The bot User:Mr.Ibrahembot, doesn't work with these property any more. --Mr. Ibrahem (talk) 09:26, 30 October 2018 (UTC)[reply]

Qualifier constraint additions[edit]

I've added coordinate location (P625), OS grid reference (P613) and location (P276) as permissible qualifiers for statements, so as to enable the precise location for a spot height to be specified within the statement, per Q111669233#P2044. --Tagishsimon (talk) 21:22, 20 April 2022 (UTC)[reply]

Range constraint violation[edit]

I'm curious why apply a value of 200 kilometres generates a range constraint violation. The constraint is -160000 to 100000, and the accepted units include kilometers, so this seems...broken? My use cases are like Tsyklon-2 (Q367286), where the target orbit needs to be indicated, and there is no better property than this one since we don't have one for average orbital altitude. — Huntster (t @ c) 04:21, 17 October 2023 (UTC)[reply]

Do you have a concrete example? I don’t see usage of this property either in the page history of Tsyklon-2 (Q367286) or in the latest 500 edits made by you. —Tacsipacsi (talk) 18:29, 17 October 2023 (UTC)[reply]

@Tacsipacsi, look under payload mass, as a subproperty. — Huntster (t @ c) 21:35, 17 October 2023 (UTC)[reply]

@Huntster: I see. However, I have no idea why this happens. Maybe you could ask at Wikidata:Report a technical problem. (By the way, it’s called a qualifier, not a subproperty.) —Tacsipacsi (talk) 07:34, 18 October 2023 (UTC)[reply]

Property talk:P2044

Documentation

determination method (P459) values[edit]

Contents

Determination of level[edit]

Altitude[edit]

Altitude of a city?[edit]

P518 (applies to part)[edit]

Flight Height?[edit]

Truncated values[edit]

Qualifier constraint additions[edit]

Range constraint violation[edit]

Navigation menu

Property talk:P2044

Documentation

determination method (P459) values[edit]

Determination of level[edit]

Altitude[edit]

Altitude of a city?[edit]

P518 (applies to part)[edit]

Flight Height?[edit]

Truncated values[edit]

Qualifier constraint additions[edit]

Range constraint violation[edit]

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