Parameters¶
About Parameters¶
The CCHDO works frequently with many parameters common in hydrography. Provided here is a description of many common parameters encountered in exchange files.
Warning
This list may not contain every parameter which may be encountered in an exchange file. CCHDO is working on providing a machine readable list of ALL parameters which may be encountered in all files. This list will include parameters which CCHDO lacks a description for (known unknown parameters).
Until that time, parameters may appear in exchange formats from the CCHDO which are not documented here. No undocumented parameter or field will cause data integrity or usefulness issues (i.e. all undocumented parameters may be safely ignored).
Definitions¶
Provided with each parameter is a set of information in a table, the information included in that table should be interpreted as follows:
- Units:
These are the common units encountered for this parameter as it will appear in the exchange document itself. The special units of “None” means the field will be either blank or contain only whitespace.
- Data Type:
Specifies the allowed type of data in the data records for this parameter. There are three types of data, string (str), integers (int), and decimal. String data types may be any printing character except a comma
,which is the field seperator. Integer data types may only contain numbers without a decimal point, quality flags are usually integers. Decimal data types may be any real number (including an integer) and may include decimal point, the precision is not specified.
- Quality Flags:
Specifies which set of quality flag definitions should be used to interpret a quality flag column for this parameter (if present). Current quality flags are: bottle, water, ctd. See the Quality Codes section for more information
- Alternate Units:
Some parameters might have alternate units which might also be in data files.
- Error Column Label:
A parameter might contain an error or uncertanty value associated with it. The column which contains the error/uncertanty values for this parameter will have the name listed in this field.
Unlisted Parameters¶
Otherwise valid exchange files which contain parameters, units, or parameter/unit pairs that are not listed in the Common Parameters list SHALL NOT cause the file to be invalid so long as the rest of the specification is adhered to.
Pass Through¶
Authors of software which read and write exchange files SHOULD pass though unlisted parameters, units, parameter/unit pairs, and the associated data columns.
Note
This section is intended for software which is used in data management, it does not impose a requirement on authors only wishing to do analysis.
Parameters with Unknown Units¶
Sometimes data may have units which are not known.
For this reason, any parameter, including ones not yet listed in the table
bellow, MAY have the unit of ARBITRARY in the unit line.
Warning
Parameters with ARBITRARY units are NOT comparable with other
ARBITRARY parameters, including those with the same parameter name.
Common Parameters¶
This section was generated automatically from a
machine readable list of parameters,
there is also a
validation schema for the
parameters json.
EXPOCODE¶
Units |
None |
Data Type |
string |
The expedition code, assigned by the CCHDO or generated by the user. Used as the unique identifier for the cruise. Usual generation formula is ICES 4 character platform code then the cruise depature date in YYYYMMDD format. The underscore _ character may also be present.
Warning
EXPOCODE does not have woce quality codes. EXPOCODE_FLAG_W should not appear in data file Parameter and Unit Lines.
SECT_ID¶
Units |
None |
Data Type |
string |
If a repeat of a WOCE section, this is the WHP section identifier. Examples include: A12, A13.5, P02.
Warning
SECT_ID does not have woce quality codes. SECT_ID_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
There may be inconsisntency in the how line numbers are represented. For example, P02 might be present as P2, these represent the same SECT_ID. Two digit zero padded line numbers are the canonical representation, please inform the CCHDO if non zero padded line numbers are encountered.
STNNBR¶
Units |
None |
Data Type |
string |
The originator’s station identifier. Allowed characters are U+0030 to U+0039, U+0041 to U+005A, U+0061 to U+007A, and U+005F (0-9, a-z, A-Z, and _)
Warning
STNNBR does not have woce quality codes. STNNBR_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
Numeric-only station identifiers are preferred by many data users, but provision for non numeric station identifiers is retained to maintain compatibility with WOCE records.
CASTNO¶
Units |
None |
Data Type |
integer |
The originator’s cast number.
Warning
CASTNO does not have woce quality codes. CASTNO_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
Where cast number is unknown a default value of 1 MAY be inserted by data processors.
BIOS_CASTID¶
Units |
None |
Data Type |
integer |
BIOS cast number.
Warning
BIOS_CASTID does not have woce quality codes. BIOS_CASTID_FLAG_W should not appear in data file Parameter and Unit Lines.
SAMPNO¶
Units |
None |
Data Type |
string |
The sample number. Often it is the rosette position, however, groups may use their own sampling identification scheme. Allowed characters are U+0030 to U+0039, U+0041 to U+005A, U+0061 to U+007A, and U+005F (0-9, a-z, A-Z, and _)
Warning
SAMPNO does not have woce quality codes. SAMPNO_FLAG_W should not appear in data file Parameter and Unit Lines.
Warning
The value may not be numeric, ensure that any software reading the file can handle UTF-8 data of the specified allowed code points.
GEOTR_EVENT¶
Units |
None |
Data Type |
integer |
The GEOTRACES Event number. Along with the GEOTRACES sample number, it is used by the GEOTRACES comunity for sample identification.
Warning
GEOTR_EVENT does not have woce quality codes. GEOTR_EVENT_FLAG_W should not appear in data file Parameter and Unit Lines.
GEOTR_SAMPNO¶
Units |
None |
Data Type |
integer |
The GEOTRACES Sample number. Along with the GEOTRACES Event number, it is used by the GEOTRACES comunity for sample identification.
Warning
GEOTR_SAMPNO does not have woce quality codes. GEOTR_SAMPNO_FLAG_W should not appear in data file Parameter and Unit Lines.
BIONBR¶
Units |
None |
Data Type |
string |
Warning
BIONBR does not have woce quality codes. BIONBR_FLAG_W should not appear in data file Parameter and Unit Lines.
BTLNBR¶
Units |
None |
Data Type |
string |
BTLNBR_FLAG_W Definitions |
The bottle identification number. This is intended to be a permanent, unique serial number fixed to the sampling device. It may also be the an identifier fixed for the duration of a single expedition. Allowed characters are U+0030 to U+0039, U+0041 to U+005A, U+0061 to U+007A, and U+005F (0-9, a-z, A-Z, and _)
Note
The bottle number MAY have quality flags.
Warning
The value may not be numeric, ensure that any software reading the file can handle UTF-8 data of the specified allowed code points.
DATE¶
Units |
None |
Data Type |
string |
The UTC date in zero padded YYYYMMDD format. The date reported is usually cast bottom for Bottle files and cast start for CTD files. Valid range for YYYY: 0001-9999. Valid range for MM: 01-12. Valid range for DD: 01-31 (depends on month and year). The format of dates corresponds to the C-strftime format of %Y%m%d.
The date should be read as a string, but be able to be cast unambiguously to an integer. To convert from integer representation, left pad zeros to match the date format description. For example, the integer 8020202 is the date 08020202 or Feb 2nd, 802. This is a very unlikely situation.
Warning
DATE does not have woce quality codes. DATE_FLAG_W should not appear in data file Parameter and Unit Lines.
TIME¶
Units |
None |
Data Type |
string |
The UTC time in zero padded hhmm format. A single time should be reported for each cast, usually the time at cast bottom (deepest) is used. The order of preference for the reported time is: cast bottom, cast start, cast end (i.e if cast bottom is not available, the cast start time should be used).
Valid range for hh: 00-24 Valid range for mm: 00-59 The format of times corresponds to the C-strftime format of %H%M.
The time should be read as a string, but be able to be cast unambiguously into an integer. To convert from an integer, left pad zeros to match the time format description.
Warning
TIME does not have woce quality codes. TIME_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
Times represented as integers will be present in netcdf files. Times in netcdf files will be anywhere from 1 to 4 digits. E.g. a time of 6 as in integer represents 6 minutes after midnight or 0006
Midnight is a special case in that it has two valid representations: 0000 and 2400. The date 20140202 at time 0000 is the same instant as the date 20140201 at time 2400. This corresponds to times allowed by ISO 8601.
Use BTL_TIME to report the time of individual bottle closures.
Warning
Time is not a required parameter! If time is not present, then the temporal resolution of the data is reduced to a 24 hour period. It is the responsibility of the user of the data to omit files/casts which do not meet their temporal resolution requirements.
LATITUDE¶
Units |
None |
Data Type |
decimal |
The latitude as a signed decimal number. By convention, is positive in the northern hemisphere and negative in the southern hemisphere. Positive values do not include a + character (U+002B), negative values are prefixed with a - character (U+002D).
Warning
LATITUDE does not have woce quality codes. LATITUDE_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
Only one latitude SHOULD be reported for a cast, typically this is the ship possition when the cast is at the bottom (deepest), but this is not guaranteed.
Use BTL_LAT to include positions of individual bottle closures.
Warning
Since this parameter has no units, the positive in the northern hemisphere and negative in the southern hemisphere MUST be strcitly adhered to.
The geographic coordinate system is not currently reported.
LONGITUDE¶
Units |
None |
Data Type |
decimal |
The longitude as a signed decimal number. By convention, is positive in the eastern hemisphere and negative in the western hemisphere. Positive values do not include a + character (U+002B), negative values are prefixed with a - character (U+002D).
Warning
LONGITUDE does not have woce quality codes. LONGITUDE_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
Only one longitude SHOULD be reported for a cast, typically this is the ship possition when the cast is at the bottom (deepest), but this is not guaranteed.
Use BTL_LON to include positions of individual bottle closures.
The longitudes of -180 and 180 describe the same meridian.
Warning
Since this parameter has no units, the positive in the eastern hemisphere and negative in the western hemisphere convention MUST be strcitly adhered to.
The geographic coordinate system is not currently reported.
DEPTH¶
Units |
METERS |
Data Type |
decimal |
The reported depth to the bottom. Corrected depths are preferred to uncorrected depths.
Warning
DEPTH does not have woce quality codes. DEPTH_FLAG_W should not appear in data file Parameter and Unit Lines.
Note
Documentation should be provided describing how the depth was calculated/corrected, typically in the comment fields.
Warning
This is NOT the depth of bottle closures.
CTDPRS¶
Units |
DBAR |
Data Type |
decimal |
CTDPRS_FLAG_W Definitions |
The corrected pressure as measured by the CTD.
Note
Typically does not have quality flags.
CTDRAW¶
Units |
DBAR |
Data Type |
decimal |
CTDRAW_FLAG_W Definitions |
The uncorrected pressure as measured by the CTD.
Note
Typically does not have quality flags.
CTDTMP¶
Units |
ITS-90 |
Data Type |
decimal |
CTDTMP_FLAG_W Definitions |
|
Alternate Units |
IPTS-68,DEG C |
The corrected temperature as measured by the CTD.
Note
Typically does not have quality flags.
CTDSAL¶
Units |
PSS-78 |
Data Type |
decimal |
CTDSAL_FLAG_W Definitions |
The corrected salinity as measured (calculated) by the CTD.
SALNTY¶
Units |
PSS-78 |
Data Type |
decimal |
SALNTY_FLAG_W Definitions |
The salinity measured from a bottle sample.
CTDOXY¶
Units |
UMOL/KG |
Data Type |
decimal |
CTDOXY_FLAG_W Definitions |
|
Alternate Units |
ML/L |
The corrected oxygen measured by the CTD.
NITRAT¶
Units |
UMOL/KG |
Data Type |
decimal |
NITRAT_FLAG_W Definitions |
The chemical formula for the nitrate anion is NO3-.
NITRIT¶
Units |
UMOL/KG |
Data Type |
decimal |
NITRIT_FLAG_W Definitions |
The chemical formula for the nitrite anion is NO2-.
TRITER¶
Units |
TU |
Data Type |
decimal |
Warning
TRITER does not have woce quality codes. TRITER_FLAG_W should not appear in data file Parameter and Unit Lines.
NEONER¶
Units |
NMOL/KG |
Data Type |
decimal |
Warning
NEONER does not have woce quality codes. NEONER_FLAG_W should not appear in data file Parameter and Unit Lines.
CCL4ER¶
Units |
None |
Data Type |
string |
Warning
CCL4ER does not have woce quality codes. CCL4ER_FLAG_W should not appear in data file Parameter and Unit Lines.
PAR¶
Units |
None |
Data Type |
decimal |
PAR_FLAG_W Definitions |
PAR/Irradiance, Biospherical/Licor
Note
From SBE .cnv files, no units
CTDBEAMCP¶
Units |
/METER |
Data Type |
decimal |
CTDBEAMCP_FLAG_W Definitions |
Radiative flux is the sum of shortwave and longwave radiative fluxes. In accordance with common usage in geophysical disciplines, “flux” implies per unit area, called “flux density” in physics. The volume scattering/absorption/attenuation coefficient is the fractional change of radiative flux per unit path length due to the stated process. Coefficients with canonical units of m2 s-1 i.e. multiplied by density have standard names with specific_ instead of volume_. The scattering/absorption/attenuation coefficient is assumed to be an integral over all wavelengths, unless a coordinate of radiation_wavelength is included to specify the wavelength. Attenuation is the sum of absorption and scattering. Attenuation is sometimes called “extinction”. Beam attenuation refers to the decrease of radiative flux along the direction of the incident path. It is distinguished from attenuation of the downwelling component of radiative flux from any incident direction, also called “diffuse” attenuation. Corrected for pure water attendance means the attenuation coefficient has been adjusted/calibrated to remove the influence of absorption/scattering from the water itself.
I129ER¶
Units |
None |
Data Type |
string |
Warning
I129ER does not have woce quality codes. I129ER_FLAG_W should not appear in data file Parameter and Unit Lines.
TOT_CHL_A¶
Units |
MG/M^3 |
Data Type |
decimal |
TOT_CHL_A_FLAG_W Definitions |
Total chlorophyll a measured using HPLC
SeaBass Description:HPLC DV_Chl_a + MV_Chl_a + Chlide_a + Chl_a_allom + Chl_a_prime
Note
A different measurement than CHLORA
TOT_CHL_C¶
Units |
MG/M^3 |
Data Type |
decimal |
TOT_CHL_C_FLAG_W Definitions |
HPLC chl_c1 + chl_c2 (chl_c1c2) + chl_c3
ALPHA-BETA-CAR¶
Units |
MG/M^3 |
Data Type |
decimal |
ALPHA-BETA-CAR_FLAG_W Definitions |
HPLC Alpha (Beta,epsilon) + Beta (Beta,beta) Carotenes
BUT-FUCO¶
Units |
MG/M^3 |
Data Type |
decimal |
BUT-FUCO_FLAG_W Definitions |
HPLC 19’-Butanoyloxyfucoxanthin
HEX-FUCO¶
Units |
MG/M^3 |
Data Type |
decimal |
HEX-FUCO_FLAG_W Definitions |
HPLC 19’-Hexanoyloxyfucoxanthin
BTL_LAT¶
Units |
None |
Data Type |
decimal |
Warning
BTL_LAT does not have woce quality codes. BTL_LAT_FLAG_W should not appear in data file Parameter and Unit Lines.
CTDNOBS¶
Units |
None |
Data Type |
integer |
The number of discrete observations from which the values of another data variable have been derived
Warning
CTDNOBS does not have woce quality codes. CTDNOBS_FLAG_W should not appear in data file Parameter and Unit Lines.
CTDETIME¶
Units |
SECONDS |
Data Type |
decimal |
The elapsed time of CTD pressure bin
Warning
CTDETIME does not have woce quality codes. CTDETIME_FLAG_W should not appear in data file Parameter and Unit Lines.
THETA¶
Units |
DEG C |
Data Type |
decimal |
THETA_FLAG_W Definitions |
|
Alternate Units |
ITS-90,IPTS-68 |
Note
Typically does not have quality flags.