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Documentation of the U.S. Geological Survey Oceanographic Time-Series Measurement Database

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Appendix 1. File naming convention

The filenames in this database have a lot of information encoded in them. The Woods Hole Coastal and Marine Science Center (WHCMSC) uses a different naming system than the Pacific Coastal and Marine Science Center (PCMSC) does; both systems are described in this appendix.

WHCMSC Network Common Data Form (NetCDF) filenames have the following form, in which square brackets [ ] indicate optional elements:


Sample filenames are,, and and

Descriptions of the NetDCF filename elements follow:

  • 999i or 9999i[i] represents the WHCMSC mooring number. The first three or four digits are a number assigned to a platform (mooring or tripod), roughly chronologically, as they are deployed. The next one or two digits identify the height of a sensor or instrument on the mooring or tripod, with number 1 at the top and numbers increasing with depth. The relevant depth is that of the measurement volume. In the case of multiple loggers at the same depth, an order is chosen by importance or to suit the investigator.
  • [A] represents an optional capital letter that identifies a temporal portion of the deployment. These letters are used when a mooring was redeployed but a new mooring number was not assigned, or when the dataset was broken into multiple time sections for processing.
  • bbbb represents one or more mostly lowercase letters that identify the measurements are contained in the dataset or identify the instrument type. The list of identifiers (table 1–1) has grown to identify more files as more instrument types have been used to collect data.
    - (a hyphen) separates the bbbb and ccc fields.
  • ccc represents the lowercase letters that identify processing stage. The “a” indicates a file that has passed the best basic version (BBV) review. “-cal” indicates some uncertainty or provisional status. The list of sensor codes and processing stages used in the names is shown in table 1–2.
  • [_dd] is an optional tag for other uses. For example, _d0, _d1, and _d2 are used to indicate relative positions of sensors attached to a single logger. During processing, this position may be used to differentiate data created with precruise or postcruise calibrations, or by omitting suspicious data from one of a benthic acoustic stress sensor’s (BASS's) four axes. This section is sometimes also used to indicate that the data were processed in more than one section.
  • ee represents the file type extension. The suffix ".nc" is typically used for files that have passed BBV review. Older netCDF files translated from data that were originally stored in Buoy Format often have ".cdf" extensions, but have been reviewed. In some cases, ".cdf" may be used to indicate provisional status.

Thus, a file named “” contains data collected from the fourth instrument from the top of platform 746. The “sc” indicates that the instrument acquiring the data was a SeaCAT and that the file contains temperature and conductivity data. The “-a” and “.nc” suffix both indicate the file is best basic version (BBV). The naming convention used for files in this database is diagrammed in figure 1–1 for the sample file Colors are used to help associate the fields with the codes and their descriptions. This nomenclature system has been used consistently since about 2000. The earliest files in the database may not have all the sections because fewer instrument types and processing options were available when they were created. For instance, the oldest files may have no instrument-type identifier in the name. The instrument identifiers in this example are a subset of those most commonly found; more complete lists of the instruments, processing levels and codes are shown in tables 1–1 and 1–2.

WHCMSC Nomenclature summary using as an example.

Figure 1-1: WHCMSC Nomenclature summary using as an example. ID, identifier; BBV, best basic version; NetCDF, Network Common Data Form.

There can be no confusion between a filename for data from of the tenth sensor on platform 991 (starts with 99110) and a file containing data from the first sensor on platform 1002 (starts with 10021) because there are no files in the mooring ID range of 100–199 that have more than nine sensors. There are some filenames with six leading digits to allow for four-digit platform IDs with 10 or more sensors.

Table 1-1: List of instrument codes employed in the NetCDF filenames.
[TRDI, Teledyne RD Instruments; ADCP, acoustic Doppler current profiler; ADV, acoustic Doppler velocimeter; ECO, Environmental Characterization Optics; PCADP, pulse-coherent acoustic Doppler profiler; BASS, benthic acoustic stress sensor; VACM, vector-averaging current meter; VMCM, vector-measuring current meter; MAVS, modular acoustic velocity sensor]

Code Description
abss Acoustic backscatter suspended sediment
advb Burst data from an ADV
advq Quality information associated with the processing of ADV data
advs Statistics data from an ADV
adwp Waves data from a TRDI ADCP
alm Airmar weather station
aqd SonTek Aquadopp current profiler
adwp, whp Waves data from a SonTek ADCP
arwp Waves data from a Nortek ADCP
att Attenuation data from a transmissometer
az Imagenex profiling sonar with rotating head
cs Conductivity and salinity data from a modified current meter
dcal dcal logger
dw RBR Virtuoso D|wave
ecp WET Labs ECO PAR
fan Imagenex imaging sonar
HFfan High-frequency imaging sonar
hlm Onset HOBO weather station
HRaqd High-resolution Aquadopp
hwl Onset HOBO U20
iq YSI/SonTek IQ
isus Satlantic ISUS
mc Sea-Bird MicroCAT
met Downeast buoy mounted weather station
ns Nortek Signature
obs Optical backscatter sensor
p Pressure data from any type of instrument
pcab Burst data from a PCADP
pcaq Quality information associated with processing of PCADP
pcas Statistics data from a PCADP
pen Imagenex profiling sonar
psd Pressure standard deviation calculated from burst BASS data from a MIDAS logger
pt Pressure and temperature data from a modified current meter
rcm Aanderra rotor current meter
rst, solot RBR solo temperature
rwl RBR solo water level
sc Sea-Bird SeaCAT
sg Sea-Bird Seagauge
v TRDI Sentinel V
var Variances and covariances calculated from burst BASS data from a MIDAS logger
vec Nortek Vector
wh TRDI WorkHorse ADCP

Table 1-2: Codes used to indicate processing level in NetCDF files.
[BBV, best basic version]

Processing level code Description
a1h Hour-averaged
alp 6-hour low pass filtered
cal Calibrated, or translated into scientific units, implies provisional status
all An aggregation in time
e Edited
terp Interpolated
lp Low-pass filtered BBV
q Fully processed and reviewed but of questionable quality
trm Trimmed
clk Clock fixed

PCMSC NetCDF filenames have the following form:, as in the sample filename

The filename includes the following elements:

  • EEE is the three character experiment identifier (ID), such as “ELW” for Elwha River;
  • YY is the second two digits of the year in which the experiment was conducted;
  • SSS is a site ID (We can use this to identify different platforms at a site, such as “B1T” for tripod at site B1 and “B1M” for mooring at Site B1. We can also use this for multiple deployments at the same site within a given year, such as “IT1” and “IT2.”);
  • Ii is the two digit relative height on platform (Usage is like that of the WHCMSC, but 01 is highest.); and
  • bbbb, ccc and ee follow the conventions used in WHCMSC files.

The naming convention used for PCMSC NetCDF files in this database is diagrammed in figure 1–2 for the sample file Colors are used to help associate the fields with the codes and their descriptions. There is no master list of PCMSC experiment and site identifiers; they are documented in the reports that describes the research programs.

Experiment ID Year Site ID Relative height on Platform Instrument ID Version File extension
CHC China Camp
14 The experiment happened in 2014
01 This was the highest instrument
vecs Nortek Vector, statistics
-cal provisional
nc BBV reviewed NetCDF

Figure 1-2: PCMSC nomenclature summary using as an example. ID, identifier; BBV, best basic version; NetCDF, Network Common Data Form.

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