Hi All, For reference, a measurement usually referred to as surface air temperature is a measurement taken at about 2 meters height above the surface (of the earth or ocean). It has a standard name "air_temperature" (which also applies to temperatures higher up in the atmosphere). To precisely specify the height above the surface at which the surface air temperature is measured, a scalar coordinate is defined with standard_name "height", with the value set to the actual height of measurement (usually 2 meters, as noted above). Note that this near-surface air temperature is different from "surface_temperature" which is the temperature of the surface itself.
Something similar is done for surface wind speed measurements, but the height is typically 10 meters, not 2 meters. In both cases, no special standard name is defined for these near-surface measurements. best regards, Karl On 9/12/19 9:13 AM, Nan Galbraith wrote: > Hi all - > > I'd like to second (or third ... ) the request for new standard names for > sea_water_practical_salinity_at_sea_floor and > sea_water_temperature_at_sea_floor. > > In the OceanSITES project, we deploy CTDs on mooring anchors, and it > would be good > to be able to find these records, among all the water temperature and > practical salinity > data sets on our servers. We supply a measurement depth, but it isn't > useful for this > search, since the water depth isn't mandatory in our format spec. > > These records are not exactly on the sea floor, but within a few > meters; do we need to > apply some limit to the distance? I'm thinking about the various > sea_surface_temperature > variants, surface_skin and surface_subskin, but I'm assuming this > isn't needed for sea > floor measurements. > > Thanks - Nan > > > On 9/10/19 1:59 PM, Lowry, Roy K. wrote: >> Hi again, >> >> I place great weight on the phrase 'where appropriate'. If a model >> works out electrical conductivity and then uses the PSS-78 algorithms >> to compute the salinity then using 'practical salinity' would be >> appropriate, but these are far from the norm!!! It's observational >> measurements where we really need to be careful about the types of >> salinity, but I've yet to see a measurements data set where bottom >> salinities are tagged differently from the salinities measured >> elsewhere in the water column. Consequently I don't see the need for >> the new name. >> >> Cheers, Roy. >> >> I have now retired but will continue to be active through an Emeritus >> Fellowship using this e-mail address. >> >> >> ------------------------------------------------------------------------ >> *From:* Andrew Barna <aba...@ucsd.edu> >> *Sent:* 10 September 2019 18:47 >> *Subject:* Re: [CF-metadata] new variable name request >> Thanks Roy, >> >> All the existing “sea_water_salinity” names have the sentence "The >> more precise standard names should be used where appropriate for both >> modelled and observed salinities.” So it think it was worth the ask >> if they know. >> >> -Barna >> >> > On 2019-09-10, at 07:42, Lowry, Roy K. <r...@bodc.ac.uk> wrote: >> > >> > Dear Barna, >> > >> > Perhaps the existing Standard Name would suffice for Cathy's needs >> as she is labelling model output and the models in my experience do >> not work to a specific measurement scale. This is because boundary >> condition and assimilation data sets can include measurements of more >> than one type in order to provide adequate coverage. >> > >> > Cheers, Roy. >> > >> > >> > From: CF-metadata <cf-metadata-boun...@cgd.ucar.edu> on behalf of >> Andrew Barna <aba...@ucsd.edu> >> > Sent: 10 September 2019 18:23 >> > Subject: Re: [CF-metadata] new variable name request >> > >> > Hi Cathy, >> > >> > There is already the name `sea_water_salinity_at_sea_floor` in the >> CF standard name list. However, if you know the scale you are >> calculating, a new name should be added to indicate this: >> > sea_water_practical_salinity_at_sea_floor if using PSS-78 >> > or >> > sea_water_absolute_salinity_at_sea_floor if using TEOS-10 >> > >> > I can come up with some definitions if you would like to have >> either of these proposed to the list. >> > -Barna >> > >> > >> > > On 2019-09-10, at 07:04, Cathy Smith <cathy.sm...@noaa.gov> wrote: >> > > >> > > Thanks. I will use that variable. >> > > >> > > I also calculated salinity of the ocean floor. Same question. >> > > >> > > Cathy >> > > >> > > On 9/9/19 3:44 PM, Andrew Barna wrote: >> > >> Hi Cathy, >> > >> >> > >> There is the name `sea_water_potential_temperature_at_sea_floor` >> with the following definition: >> > >> Potential temperature is the temperature a parcel of air or sea >> water would have if moved adiabatically to sea level pressure. The >> potential temperature at the sea floor is that adjacent to the ocean >> bottom, which would be the deepest grid cell in an ocean model. >> > >> >> > >> From what I can tell, there is no “in situ” sea water >> temperature name at the sea floor. I’d suggest the following name for >> this parameter with canonical units K: >> > >> `sea_water_temperature_at_sea_floor` >> > >> >> > >> Here is a possible definition basically modifying the above to >> remove the “potential” parts: >> > >> >> > >> Sea water temperature is the in situ temperature of the sea >> water. The temperature at the sea floor is that adjacent to the ocean >> bottom, which would be the deepest grid cell in an ocean model. >> > >> >> > >> There should probably also be a modification of the existing >> sea_water_temperature definition to include this new name if it is >> accepted: >> > >> >> > >> The sentence: >> > >> "There are standard names for sea_surface_temperature, >> sea_surface_skin_temperature, sea_surface_subskin_temperature and >> sea_surface_foundation_temperature which can be used to describe data >> located at the specified surfaces.” >> > >> >> > >> Should be changed to: >> > >> >> > >> "There are standard names for sea_surface_temperature, >> sea_surface_skin_temperature, sea_surface_subskin_temperature, >> sea_surface_foundation_temperature, and >> sea_water_temperature_at_sea_floor which can be used to describe data >> located at the specified surfaces.” >> > >> >> > >> -Barna >> > >> >> > >>> On 2019-09-09, at 11:23, Cathy Smith <cathy.sm...@noaa.gov> wrote: >> > >>> >> > >>> All >> > >>> >> > >>> I have a new variable request; bottom temperature. It is the >> temperature of the ocean floor (or the last level of a multi level >> ocean dataset). I searched and was unable to find it or a variable >> with "bottom" or synomyn as a level. I welcome being pointed out >> where I missed it. >> > >>> >> > >>> It is an important variable for fish and aquatic populations >> near coasts (or very shallow oceans). >> > >>> >> > >>> http://glossary.ametsoc.org/wiki/Bottom_temperature >> > >>> >> > >>> https://www.frontiersin.org/articles/10.3389/fmars.2019.00030/full >> > >>> >> >> > _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
