Netcdf meta data (shear probes)

From Atomix
Revision as of 18:16, 22 November 2023 by PeterHoltermann (talk | contribs)


Below we list the metadata required in a NetCDF data file, as well as the optional meta data we highly recommend that are included with the data set.

The parameter names should be used as listed (attention to underscores). The descriptions are example text or several options that are available for that parameter.


Required Metadata


Parameter Name Description
title E.g., Vertical micostructure profiler data from cruise XXX
authors Names of authors
summary An abstract describing the dataset
comment Supplementary technical details about the collecting and processing of the dataset
platform_type The platform from which the data are collected. From the SeaVoX Platform Categories (L06) list,

e.g. sub-surface mooring, research vessel, sub-surface glider

source The instrument used for collecting the data. For example, vertical microstructure profiler, VMP2000 SN009.
date_created The date on which the data was created, yyyy-mm-ddTHH:MM:SSZ
date_update The date on which the data was last modified, yyyy-mm-ddTHH:MM:SSZ
time_reference_year Year for time reference
time_coverage_start Time of the first data point in the dataset, yyyy-mm-ddTHH:MM:SSZ
time_coverage_end Time of thelast data point in the dataset, yyyy-mm-ddTHH:MM:SSZ
geospatial_lat_min Southern bound of data, decimal degrees, negative for South
geospatial_lat_max Northern bound of data, decimal degrees, negative for South
geospatial_lon_min Western bound of data, decimal degrees, negative for West
geospatial_lon_max Eastern bound of data, decimal degrees, negative for West
fs_fast Sampling frequency for fast (turbulence) channels
fs_slow [math]\displaystyle{ ^a }[/math] Sampling frequency for slow channels (if exist)
profiling_direction E.g., horizontal, vertical, or glide
fft_length Length of the Fast Fourier transform segments (in data points; note, fft_lengths_sec in seconds is optional)
diss_length Length of data (in data points) used for each dissipation estimate
overlap Length of overlap (in data points) in diss_length
goodman Vibration coherent noise removal using the Goodman algorithm. 0=not applied; 1=applied
HP_cut The high-pass filter cutoff frequency in Hz. Can be zero for no filtering.
conventions A comma-separated list of the conventions that are followed by the dataset. e.g., CF-1.6, ACDD-1.3, ATOMIX
history Provides an audit trail for modifications to the original data; e.g., Version 1
data_mode D (D)elayed

[math]\displaystyle{ ^a }[/math] or fast_ctd or similar if such records are included

Optional Metadata


Parameter Name Description
fft_length_sec seconds
diss_length_sec seconds
overlap_sec (for diss_length_sec) seconds
f_AA Hz, the anti-aliasing frequency.
FOM_limit non-dimensional, if absent the FOM QC-flag is not set. Typically, 1.15.
diss_ratio_limit non-dimensional, if absent the dissipation ration QC-flag is not set. Typically, 2.77.
despike_shear_fraction_limit non-dimensional, if absent the de-spike fraction QC-flag is not set. Typically, 0.05.
despike_shear_iterations_limit non-dimensional, if absent the de-spike iteration passes QC-flag is not set. Typically 8.
variance_resolved_limit threshold for the minimum percent of variance resolved in a shear spectrum. Typically 50%.
spectral_model e.g., Nasmyth, Lueck or Panchev-Kesich
spectrum_std statistical uncertainty (standard deviation) of the natural logarithm of spectrum of shear
num_vibration_goodman number of vibration or acceleration time series used to clean the shear spectrum
f_limit upper limit to exclude frequencies that have contaminations. Typically infinity.
fit_2_isr dissipation threshold to use the method of fitting to the inertial subrange. Typically 10-5 W/kg.
eps_remove_top_meters if applicable, upper meters removed from dissipation estimates (e.g., because of ship)
area e.g., Arctic Ocean, Barents Sea
geospatial_vertical_min 0
geospatial_vertical_max in m
geospatial_vertical_positive down, up
institution e.g. University of Bergen
principal_investigator Name of Principal Investigator
contact email address of corresponding author (usually principal investigator)
project_name name of project for which the data was collected
cruise name of cruise from which the data was collected
vessel name of vessel from which the data was collected
source From the SeaVoX Platform Categories vocabulary (L06) list, e.g. “subsurface mooring”, ”ship”, ""sub-surface gliders"", ""autonomous underwater vehicle"" (CF)
references key references
keywords relevant keywords describing data e.g. shear probes
creator_name name of person who generated the file
creator_email email address of person who generated the file
creator_url website address of the creator
acknowledgement acknowledgements for this data. e.g. this could include crew of ship or funders
station_name name of station

return to Dataset requirements for shear probes