Talk:Salinity

earlier comments
Is the technical term really halinity? The halogens make up a portion of salinity. Similarily, chlorinity is not a technical term for salinity, but is a portion of the salinity. :Piyrwq 00:51, 10 August 2005 (UTC)
 * Actually, there is no consistency (as near as I can tell) in use of this term, in the main because there are lots more "oceanographers" out there than limnologists. The term is real, but education being what it is these days in the US, I would not be surprised if few have encountered it. Chlorinity is a technical term regularly used for "salinity", the latter having been defined to obscurity by oceanographers. - Marshman 04:24, 10 August 2005 (UTC)

salinity of sea water
I WORK IN A WATER LABORATORY IN A SEA WATER INJECTION FACILITY. THE SALINITY METER I USE SHOWS SALINITY IN PERCENTAGE. WHAT DOES IT ACTUALLY MEAN? DOES 35% SALINITY MEAN THAT THERE IS 35 GRAMS OF SALT IN 100 GRAM WATER?
 * The measurement "parts per thousand or ppt or o/oo" is a ratio just as is percentage (or parts per hundred or %). So, the answer is yes, that is sort of what it means: 35 grams in 100 grams of the solution. Seawater has a salinity of around 3.4 or 3.5%. If your meter is reading 35% that is an awful lot of salt (imagine a container that is 1 part salt in 2 parts water!). (Which is to say, "No, your meter is not telling you that there are 35 grams of salt in 100 grams of your water", but rather that there are 35 parts-per-thousand grams of salt in a thousand parts/ grams of your water.  Very different!!!  Please forgive me for clarifying here. KDS4444 (talk) 21:50, 5 August 2017 (UTC))  I suspect it should be reading 3.5% or is reading 35 o/oo - Marshman 19:18, 11 January 2006 (UTC)


 * The meter probably measures conductivity and is calibrated using some reference solutions such that the 35 reading corresponds to 32.4356 g of KCl at 15°C in a 1 kg solution. Maybe see http://www.toptotop.org/climate/psu.php or http://www.osil.co.uk/web/osil/osil.nsf/(AllbyUnid)/28E889A530E6694A80256D2B0031C90F?opendocument 139.70.10.66 19:33, 11 January 2006 (UTC)
 * Yes, 1 kg being 1000 parts solution, so reading not in percent - Marshman

The ppt markings need to be made clearer. I thought it was a wacky percent sign from looking at the chart. Night Gyr (talk/Oy) 15:36, 24 January 2007 (UTC)

The unit of measure is still confusing. I came here from the saline water article, where there is a very clear definition of salinity, but then they go on to use "NaCl, wt%" as the measuring unit for salinity in a chart, so i just wanted to know if it meant weight of salt over weight of water, or weight of salt over weight of the saline solution (as a whole)... and then i get here and they say that salinity is grams of salt over kilograms of sea water... i can work with the mixing of grams and kilograms, but why bring "sea water" into the equation??? What is the international definition of "sea water"? I assume they meant "pure water" or "fresh water" because if not, then the salinity of pure water is a negative value around "-35ppt" because pure water has no salt and sea water has around 35ppt... and still i don't know if the divider is the weight of just the water or the whole saline solution. — Preceding unsigned comment added by 186.61.149.137 (talk) 21:03, 11 March 2019 (UTC)

salt water
Can anyone tell me why humans can't drink salt water?
 * Have a look at the seawater article. Cheers, --Plumbago 09:33, 26 September 2006 (UTC)

source of salinity
My daughter asked me why the oceans are so salty.

This page doesn't say why. Can someone add this to the page please? —The preceding unsigned comment was added by 203.38.122.195 (talk) 21:03, 27 February 2007 (UTC).

They are saline because of freshwater run off. This brings dissolved minerals to the sea. Subduction of the seabed removes the minerals and this is why the oceans have a salinity of approximately 35. I read about this hypothesis in Bill Brysons "A short history of nearly everything". The reason I am at this article is to find out if Wikipedia has a standard unit for reporting salinity? I am used to reporting it as a unitless ratio, is this the case for wikipedia?Celticbattlepants 01:55, 21 June 2007 (UTC)

salinity has NO unit
The practical salinity scale was defined as a conductivity ratio, NOT redefined in practical salinity units. So all salinity values should be given without any physical unit. For some more in depth explanation of that, see e.g. http://www.oceanographers.net/forums/showthread.php?t=902 —Preceding unsigned comment added by Prieni (talk • contribs) 13:52, 26 September 2007 (UTC)

I am a process engineer. I find that use of absolute units is very much easier. For quantities use of mass is most helpful. In the case of salinity this would best be expressed in mass of salt / unit volume of water or unit mass of water. In this way any required calculations are much easier than starting from things such as conductivity ratio. The reason I suspect that conductivity ratio is used is that it is easier to measure in a lab. However such figures really need to be cross referenced to absolute units to make use of them. Jerry 88.209.72.163 (talk) 11:00, 10 December 2008 (UTC)

There is a mixture of references to g/L and g/Kg without explanation. I realise there is no difference for most practical purposes. The headline definition and the assertion the the measure is dimensionless imply that Kg is technically correct. Obviously L is also used. — Preceding unsigned comment added by Tesspub (talk • contribs) 09:46, 27 November 2018 (UTC)

Hypersaline
Hypersaline redirects here but is not mentioned. Are the terms hypersaline and hyperhaline synonyms? Hypersaline gets 50 times as many hits on google as hyperhaline, so I think that it should at least get a mention as an alternative. Mikenorton (talk) 21:35, 30 March 2008 (UTC)

Link on algorithms
It was not my intention to create a spam link. I now know that this link does not fit the standards of Wikipedia. I just thought these information for converting different entities could be helpful. What about the link http://www.code10.info/index.php?view=category&id=54%3Acat_coding_algorithms_seawater&option=com_content&Itemid=56. Would this fit? Bye, Jan. —Preceding unsigned comment added by Boolstring; (talk • contribs) 09:41, 25 January 2009 (UTC)

New graphic from Aquarius satellite
There's a new world map of oceanic salinity available from NASA's Aquarius mission at this link (not yet uploaded to Wikimedia Commons). See this article. Spikebrennan (talk) 15:26, 27 September 2011 (UTC)

PSU not motivated in the article
The "practical salinity unit" is effectively not motivated in the article since it completely lacks any reference to physical salinity. The statement "It is not the case that a salinity of 35 exactly equals 35 grams of salt per liter of solution." only says that PSU is not equal to grams per liter. But without any hint, how much salt content equals a given PSU value, the use of PSU in the article is completely meaningless. A conversion table between PSU and g/l would be useful, but it seems that even Google doesn't find any conversion table.--SiriusB (talk) 14:33, 17 July 2013 (UTC)

Extensive plagiarism
There is a large overlap between this article and R. Manivanan, Water Quality Modeling: Rivers, Streams, and Estuaries, 2008. At first, I deleted the common text from this article, assuming that Wikipedia had plagiarized Manivanan. But Manivanan was apparently published in 2008, and our content dates from before then. Also, footnotes were progressively added to the Wikipedia text, with Manivanan sharing footnotes which weren't in the original version of the Wikipedia text. So it looks as though Manivanan may have plagiarized Wikipedia. There may be other explanations, but at this point, it looks as though Wikipedia is not the plagiarizer. --Macrakis (talk) 03:40, 30 July 2013 (UTC)

blood, Dead Sea, requested additions
salinity of human blood 9 ppt see Saline. Facts to add: Salinity of Dead Sea, Great Salt Lake. GangofOne (talk) 21:52, 3 August 2015 (UTC),

ppt normally stands for parts per trillion, recommend to not use ppt for thousands fractions
In the vast majority of scientific fields, as well as other areas, "ppt" stands for "parts per trillion", i.e. not "parts per thousand". Even the wiki-page on Parts-per notation boldly states that ppt should not be used for parts per thousand:

"One part per thousand should generally be spelled out in full and not as "ppt" (which is usually understood to represent "parts per trillion")."

The page also informs the reader that oceanography is one of the few fields where ppt is used for parts per thousand. However, most Wikipedia readers are not oceanographers, for this reason it might be good to obey the recommendations in the "parts per notation" page and not use ppt for thousandth notation, instead write it in full or use more common notations, e.g. per mille (‰).

EV1TE (talk) 23:25, 5 May 2018 (UTC)


 * I went ahead and fixed it. It actually took me a while to understand what these "parts per trillion" were intended to mean!
 * David Marjanović (talk) 13:36, 23 September 2021 (UTC)