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Data Submission Manual
Submit DataData ReportingTemplatesCategoryTrace GasesVOCNMHClevel2    October 1, 2020

The example template given below contains the metadata fields that are commonly included when reporting data related to this specific template. Some of these metadata elements may not be relevant for your data reporting, like AIRS station ID for stations outside North America or the various QA measure data when there is no QA measure for the data. Such metadata elements could be let out. If you want to include additional metadata elements that are not given in the example template, there is a complete list here.  In case of any doubt about such additional metadata, please consult the EBAS team!


Template for submission of NMHC data - Level 2

This template should be used for submitting measurement data of NMHC. Hydrocarbons are measured by a variety of methods and instruments, including automated monitors in the field (online methods) and manual based canister sampling in the field followed by subsequent analyses in the lab (offline methods). For instruments that measure both NMHC and OVOC, such as PTR-MS, you should use the single template that is most suited and not split the data into two.  Please be aware of the points to note in the list below.

Points to note

Clicking on a specific line in the example template will provide a detailed explanation and possible options for each of the metadata elements. Please contact ebas@nilu in case of broken links etc.

  • The term “Instrument (like in “instrument name” ) refers to the instrument in the field. Thus, for offline data this refers to the sampling equipment whereas for online data it refers to the monitor. Multiple names are separated by plus signs (‘+’).
  • The term “analytical instrument” refers to the to analyse instrument used in the lab for offline data. This metadata element is not used for online data.
  • The standard unit of NMHC data is pmol/mol.
  • For offline data the starttime and endtime should be set to the sampling period. These data would normally have irregular timing and a time interval set to 0.
  • In the example, the detection limit equals 3 times the precision. If you wish to report a detection limit as a fixed value, specify the value in the variable section, Detection limit=<value unit>. If this is the case, remember to change the Detection limit expl.
  • Please use the following links for detailed information about metadata elements reffering to analytical measurement information (for reporting offline data): Analytical measurement technique, Analytical laboratory code, Analytical instrument name, Analytical instrument manufacturer, Analytical instrument model, Analytical instrument serial number
  • QA measures: Can be set in the file global metadata (as the example below). This way it applies to all variables in the file. It could also be overridden for each variable by specifying the metadata in the VNAME lines of the nasa ames file, see this example. In addition, empty metadata values ("tag=") are interpreted as "metadata element not reported". This is used e.g. when resetting the metadata elements for one variable (when it was set to any value in the file global metadata).

Downloading template as text file

You could download the template and start to modify the text with your own metadata. Due to limitations of the online portal we could not provide files with the .nas file extension. So please download the text file and edit, and remember to use the .nas file-extension when you create your datafile: 



* To validate the file, please use the EBAS Submission Tool

Flags commonly used with this format:

Group 0: Valid data

Flag Validity Description
000 V Valid measurement

Group 1: Exception flags for accepted, irregular data

Flag Validity Description
147 V Below theoretical detection limit or formal Q/A limit, but a value has been measured and reported and is considered valid

Group 5: Chemical problem

Flag Validity Description
559 V Unspecified contamination or local influence, but considered valid

Group 6: Mechanical or instrument problem

Flag Validity Description
653 V Sampling period shorter than normal, considered representative. Observed values reported
654 V Sampling period longer than normal, considered representative. Observed values reported

Group 9: Missing flags

Flag Validity Description
999 M Missing measurement, unspecified reason

Template for Data Submission (example for online NMHC data):

84 1001
Schmidbauer, Norbert; Someone, Else
NO01L, Norwegian Institute for Air Research, NILU, , Instituttveien 18, , N-2027, Kjeller, Norway
Solberg, Sverre
1 1
2015 01 01 2016 01 24
days from file reference point
1 1 1 1 1 1 1 1 1 1 1 1 1
9999.999999 999999.999 99999.999 99999.999 9.999 99999.999 99999.999 99999.999 9.999 99999.999 999999.999 99999.999 9.999
end_time of measurement, days from the file reference point
ethane, pmol/mol, Detection limit=
ethane, pmol/mol, Statistics=expanded uncertainty 2sigma
ethane, pmol/mol, Statistics=precision
numflag, no unit
propane, pmol/mol, Detection limit=
propane, pmol/mol, Statistics=expanded uncertainty 2sigma
propane, pmol/mol, Statistics=precision
numflag, no unit
n-butane, pmol/mol, Detection limit=
n-butane, pmol/mol, Statistics=expanded uncertainty 2sigma
n-butane, pmol/mol, Statistics=precision
numflag, no unit
Data definition:                         EBAS_1.1
Set type code:                           TU
Timezone:                                UTC
File name:                               NO0042G.20150101000000.20160124000000.online_gc.NMHC.air.1y.2h.NO01L_Medusa-9.NO01L_AGAGE.lev2.nas
Startdate:                               20150101000000
Revision date:                           20160124000000
Version:                                 1
Version description:                     initial revision, manually inspected
Data level:                              2
Period code:                             1y
Resolution code:                         2h
Sample duration:                         40mn
Orig. time res.:                         40mn
Station code:                            NO0042G
Platform code:                           NO0042S
Station name:                            Zeppelin mountain (Ny-Ålesund)
Station WDCA-ID:                         GAWANO__ZEP
Station GAW-ID:                          ZEP
Station GAW-Name:                        Zeppelin Atmospheric Observatory
Station land use:                        Arctic tundra
Station setting:                         Global
Station GAW type:                        G
Station WMO region:                      6
Station latitude:                        78.906667
Station longitude:                       11.888333
Station altitude:                        474.0m
Measurement altitude:                    474.0m
Measurement height:                      10.0m
Component:                               NMHC
Unit:                                    pmol/mol
Matrix:                                  air
Instrument type:                         online_gc
Laboratory code:                         NO01L
Instrument name:                         Medusa-9
Instrument manufacturer:                 AGAGE+Agilent+Agilent
Instrument model:                        MEDUSA+6890N+5975B
Instrument serial number:                70810508
Method ref:                              NO01L_AGAGE
Standard method:                         SOP=ACTRIS_VOC_2014 
Calibration scale:                       NPL
Calibration standard ID:                 Manufacturer Linde; Batch 1234567
Secondary standard ID:                   Manufacturer Linde; Batch 123489
Inlet type:                              Hat or hood
Inlet description:                       Downward facing with hood
Detection limit expl.:                   Detection limit equals 3 times the precision 
Measurement uncertainty expl.:           "Includes reproducibility (precision) + systematic errors (accuracy). Ref:" 
Zero/negative values code:               Zero/negative possible
Zero/negative values:                    Zero and neg. values may appear due to statistical variations at very low concentrations
QA1 measure ID:                          ACTRIS-VOC-1
QA1 date:                                20120515
QA1 document URL:                        "" 
Originator:                              Schmidbauer, Norbert,, Norwegian Institute for Air Research, NILU, Atmosphere and Climate Department, Instituttveien 18,, N-2027, Kjeller, Norway
Originator:                              Someone, Else,, Some nice Institute, WOW, Super interesting division, Street18,, X-9999, Paradise, Noway
Submitter:                               Solberg, Sverre,, Norwegian Institute for Air Research, NILU, Atmosphere and Climate Department, Instituttveien 18,, N-2027, Kjeller, Norway
Acknowledgement:                         Request acknowledgement details from data originator
Comment:                                 Preconcentration MEDUSA, o3 removed, nodryer, 3-hourly calibration interval
starttime endtime ethane ethane_ac ethane_pr numflag_ethane propane propane_ac propane_pr numflag_propane n-butane n-butane_ac n-butane_pr numflag_n-butane
0.000000 0.027778 1567.223 700.879 402.144 0.000 213.512 130.085 52.924 0.000 1567.223 700.879 402.144 0.000
0.083333 0.111111 999999.999 99999.999 99999.999 0.999 99999.999 99999.999 99999.999 0.999 99999.999 999999.999 99999.999 0.999
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