General description

The station header includes, in the first lines, mandatory information like the time-series or trajectory identifier, date, time, location, list of observed parameters and units. The environmental information on the observations archived either behind " *DC= " (for Data collection), other relevant information behind "*DM=" (for Data Management) or "COMMENT" is optional.

• The four first observed parameters are the reference parameter for the time series:
  • YEAR : Year (YYYY)
  • MNTH : Month (MM)
  • DAYX : Day within month (DD)
  • TIME : Time within day (HH24MISS)
  • for trajectories 2 additionnal parameters are added:
    • LATX : latitude in decimal degrees
    • LONX: Longitude in decimal degrees
• BP = Beginning Position
• SL = string length
• MAND = Mandatory if X in the column
• NP = number of observed parameters incl. the reference (pressure)
• NCO = number of comment lines in the header

LINE	FIELD Access to codification	DESCRIPTION	BP	SL	TYPE	MAND
1	start character	'*'	1	1	char	X
	reference	MEDATLAS ref.(cruise+station+cast)	2	18	char	X
	key word	'Data Type='	21	10	char	X
	data type	SeaDataNet C77 vocabulary list	31	3	char	X
2	date	'*DATE='DDMMYYYY	1	14	char	X
	time	'TIME='HHMN	16	9	char	X
	latitude N/S	'LAT='N or S	26	5	char	X
	lat. degrees	latitude degrees (0 to 90)	31	2	char	X
	lat. minutes	latitude minutes.hundredth	34	5	char	X
	longitude E/W	'LON=', E or W	40	5	char	X
	long. degrees	longitude degrees (0 to 180)	45	3	char	X
	long. minutes	minutes.hundredth	49	5	char	X
	key word	'DEPTH='	55	6	char	X
	bottom depth	bottom depth in metres (nothing if unknown)	61	6	num
	key word	'QC='	68	3	char	X
	time flag	QC flag on date and time	71	1	num	X
	lat. flag	QC flag on latitude	72	1	num	X
	long. flag	QC flag on longitude	73	1	num	X
	depth flag	QC flag on bottom depth	74	1	num	X
3	key word	'*NB PARAMETERS= '	1	15	char	X
	nb. of columns	number of measured parameters (NP)	16	2	num	X
	key word	'RECORD LINES='	19	13	char	X
	number of lines	number of observation records (NL)	32	5	num	X
3+1to 3+NP	1st character	*	1	1	char	X
	code param. p	Code for parameter p	2	4	char	X
	parameter p	parameter full name (P09 def.)	7	30	char	X
	unit param. p	('IS/P09 unit')	37	30	char	X
	key word	'def.='	68	5	char	X
	default val.	string of '9'.string of '9' same format as the parameter p	73	nlen(np)	num	X
4+NP	key word	'*GLOBAL PROFILE QUALITY FLAG='	1	29	char	X
	profile QC	global quality flag for the profile	30	1	num	X
	key word	'GLOBAL PARAMETERS QC FLAGS='	32	27	char	X
	profile QC	global quality flags for the NP parameter	50	NP	num	X
5+NP	key word + collect hist.1	'*DC HISTORY=' method or instrument used when the data was collected	1	80	char	X
6+NP	collect hist.2	'*'continuation	1	80	char	X
7+NP	key word + data manag.. hist.1	'*DM HISTORY=', data management history	1	80	char	X
8+NP	archv. hist.2	'*'continuation	1	80	char	X
9+NPto 8+NP+NCO	key word	'*COMMENT'	1	8	char	X
	comment	'*'comment line 1	1	80	char	X
	comment	'*'comment line n	1	80	char
9+NP+NCO	key word + surface obs. 1	'*SURFACE SAMPLES=', samples	1	80	char	X
10+NP+NCO	surface obs. 2	'*'continuation	1	80	char	X

Specific information for SeaDataNet

A set of ‘special’ mandatory comment lines that must appear at the end of the station header comments. Their function is to map the text strings used to label the data columns to standardized SeaDataNet concepts, which is necessary if data files from different sources are to be combined in a meaningful way.

The comment must contains the following consecutive lines: *SDN_parameter_mapping

This is followed by a line for each parameter column, including the primary variable, made up from three parts, each tagged to look like an XML element:

• subject element: This contains the MEDATLAS parameter code prefixed by the text ‘SDN:LOCAL:’ to encode it as a SeaDataNet URN
• object element This contains the URN to a concept from the SeaDataNet P01 vocabulary which contains over 37,000 terms)
• units element This contains a URN for the storage units used IN THE MEDATLAS FILE for the data column in the SeaDataNet P06 vocabulary

Examples of valid data column semantic descriptions:

*<subject>SDN:LOCAL:YEAR</subject><object>SDN:P01::YEARXXXX</object><units>SDN:P06::UUUU</units>
*<subject>SDN:LOCAL:MNTH</subject><object>SDN:P01::MNTHXXXX</object><units>SDN:P06::UUUU</units>
*<subject>SDN:LOCAL:DAYX</subject><object>SDN:P01::DAYXXXXX</object><units>SDN:P06::UUUU</units>
*<subject>SDN:LOCAL:TIME</subject><object>SDN:P01::AHMSAA01</object><units>SDN:P06::UHMS</units>
*<subject>SDN:LOCAL:HCSP</subject><object>SDN:P01::LCSAZZ01</object><units>SDN:P06::UVAA</units>
*<subject>SDN:LOCAL:HCDT</subject><object>SDN:P01::LCDAZZ01</object><units>SDN:P06::UAAA</units>
*<subject>SDN:LOCAL:EWCT</subject><object>SDN:P01::LCEWZZ01</object><units>SDN:P06::UVAA</units>

*EDMO_CODE = EDMO identifier of the data centre managing the CDI

*LOCAL_CDI_ID = local identifier of the station

To guarantee the iniquity of the LOCAL_CDI_ID, the local identifier of the station must be a concatenation of the MEDATLAS cruise reference code, 5 last characters of the station code and station data type.

Example of a valid LOCAL_CDI_ID lines:

*LOCAL_CDI_ID = FI35199758001_00483_D01

Optional linkage to external resources may also be added that provide links to web resources related to the data in the file.

Example of linkage to external resources:

Link to the xml description of the CDI:

*<sdn_reference xlink:href="http://seadatanet.maris2.nl/v_cdi_v3/print_xml.asp?edmo=486&identifier=FI35199758001_04830_D01" xlink:role="isDescribedBy" xlink:type="SDN:L23::CDI"/>

Time series reference

String of 18 characters (no blank character allowed)

Example : FI3519975800100483

• cruise reference (13 characters) : FI35199758001
• station number (5 characters) : 00483

• BP = Beginning Position
• SL = string length

FIELD Access to codification	DESCRIPTION	BP	SL	TYPE	MAND.
cruise reference	Cruise reference to which the station belongs	1	13	char	X
station number	station reference	4	5	char	X

Detailed information

First character of the header lines

All lines begin with the character " * ".

Latitude and Longitude

In order to avoid ambiguity, N/S and E/W are specified for latitude and longitude instead of signs.

Missing information

Missing time should be assigned to '9999' and "TIME IS UNKNOWN" added in comment line.

Other missing information (when optional) in character strings: 'X' as many times as the missing string length or 'UNKNOWN' or ‘9’ for numerical values (like bottom depth).

Parameters List

The first observed parameter is the reference, which for vertical profiles must be the pressure in decibar.

The list of each observed parameter (pressure,temperature, salinity, nutrients) include the parameter code, name, unit (IS, P09) and default value. A different unit corresponds to a different parameter code.

History and information on the data processing

In order to maintain some flexibility with the format and not to loose existing complementary information on the data processing, meteorological observations etc. not taken into account in the format, three specific fields terminate each header profile:

*DC HISTORY for the information linked to the data collection at sea (like instrument, calibration)

*DM HISTORY for the information linked to the data management and archiving (like the source latitude if the sign or the value has been changed)

*COMMENT for all optional data and meta data like the end location of the time series, any meteorological relevant data. The number of comment lines is not limited.

For the time series, 5 lines must be added in the comment lines of the header :

LINE	FIELD Access to codification	DESCRIPTION	BP	SL	TYPE	MAND
1	key word	'*ADDITIONNAL INFORMATION - TIME SERIES	1	38	char	X
2	key word	'*EDATE=''	1	7	date	X
	end date	End date of the time serie : format DDMMYYYY	8	8	char	X
	key word	'ETIME='	17	6	char	X
	end time	End time of the time serie : format HHMN	23	4	time	X
	key word	'ELAT='	28	5	char	X
	end latitude	End latitude of the time serie : N(or S)DD MM.99	33	9	lat.	X
	key word	'ELON='	43	5	char	X
	end longitude	End longitude of the time serie : E(or W)DDD MM.99	48	10	long.	X
	key word	'EDEPTH='	59	7	char	X
	end depth	End bottom depth of the time serie	66	6	num
	key word	'QC='	73	3	char	X
	time flag	QC flag on end date and end time	76	1	num	X
	lat. flag	QC flag on end latitude	77	1	num	X
	long. flag	QC flag on end longitude	78	1	num	X
	depth flag	QC flag on end bottom depth	79	1	num	X
3	key word	'*SENSOR DEPTH='	1	14	char	X
	sensor depth	Nominal sensor depth in meters	15	5	num	X
	key word	'(metre)'	21	7	char	X
	key word	'DISTANCE TO BOTTOM='	40	19	char	X
	dist. bottom	Distance to bottom in meters	59	5	num
	key word	'(metre)'	65	7	char
	key word	'QC='	73	3	char	X
	depth flag	QC flag on sensor depth	76	1	num	X
	dist. flag	QC flag on distance to bottom	77	1	num	X
4	key word	'*DURATION='	1	10	char	X
	duration	Time serie duration in days	11	5	num
	key word	(day)	17	5	char
	key word	QC=	73	3	char	X
	duration flag	QC flag on the duration of the time serie	76	1	char	X
5	key word	'*SAMPLING RATE='	1	15	char	X
	samp. rate	Sampling rate in seconds	16	5	num
	key word	(second)	22	8	char
	key word	'MAGNETIC DECLINATION='	40	21	char	X
	mag. decl.	Magnetic declination in degrees (format 99.9), default value = -999	61	4	num	X
	key word	(degree)	66	8	char	X

Last line

The last line begins with the character " * " and the parameter P09 codes as titles of the columns of observations. They should be in the same order than in the detailed description of the measured parameters.