Netcdf meta data (shear probes): Difference between revisions

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! Parameter Name !! Description
! Attribute Name !! Description !! Convention
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| fft_length_sec ||  seconds
| fft_length_sec ||  Length of the Fast Fourier transform segments in seconds || ATOMIX
|-
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| diss_length_sec  || seconds
| diss_length_sec  || Dissipation estimate data length in seconds || ATOMIX
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|-
| overlap_sec ||  (for diss_length_sec) seconds
| overlap_sec ||  Length of overlap (in seconds) in diss_length_sec || ATOMIX
|-
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| f_AA ||  Hz, the anti-aliasing frequency.
| f_AA ||  The anti-aliasing frequency in Hz || ATOMIX
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| FOM_limit ||  non-dimensional, if absent the FOM QC-flag is not set. Typically, 1.15. It can be as large as 1.4.
| FOM_limit ||  Figure of merit limit for quality assurance. Typically between 1.15 and 1.4. || ATOMIX
|-
|-
| diss_ratio_limit ||  non-dimensional, if absent the dissipation ration QC-flag is not set. Typically, 2.77.
| diss_ratio_limit ||  The limit to identify anomalously large disagreement between dissipation estimates from probes. The magnitude of the difference of the natural logarithm of two dissipation estimates should be smaller than diss_ratio_limit <math>\times \sigma_{\ln \varepsilon}</math>. Typically, 2.77
|-
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| despike_shear_fraction_limit ||  non-dimensional, if absent the de-spike fraction QC-flag is not set. Typically, 0.05.
| despike_shear_fraction_limit ||  non-dimensional, if absent the de-spike fraction QC-flag is not set. Typically, 0.05.

Revision as of 19:39, 24 May 2024


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


Attibute Name Description Convention
title A comprehensive title for the dataset including the time and location aspect CF, ACDD
authors A list of authors ATOMIX
summary An abstract describing the dataset ACCD
comment Supplementary technical details about the collecting and processing of the dataset CF, ACDD
platform_type The platform from which the data are collected, e.g., sub-surface mooring, research vessel, sub-surface glider ACDD
source The instrument used for collecting the data. For example, vertical microstructure profiler, VMP2000 SN009 CF, ACDD
date_created The date on which the data were created, yyyy-mm-ddTHH:MM:SSZ ACDD
date_modified The date on which the data were last modified, yyyy-mm-ddTHH:MM:SSZ ACDD
time_reference_year Year for time reference ATOMIX
time_coverage_start Time of the first data point in the dataset, yyyy-mm-ddTHH:MM:SSZ ACDD
time_coverage_end Time of thelast data point in the dataset, yyyy-mm-ddTHH:MM:SSZ ACDD
geospatial_lat_min Southern bound of data, decimal degrees, negative for South ACDD
geospatial_lat_max Northern bound of data, decimal degrees, negative for South ACDD
geospatial_lon_min Western bound of data, decimal degrees, negative for West ACDD
geospatial_lon_max Eastern bound of data, decimal degrees, negative for West ACDD
fs_fast Sampling frequency for fast (turbulence) channels ATOMIX
fs_slow [math]\displaystyle{ ^a }[/math] Sampling frequency for slow channels (if exists). Alternative names could be, e.g., fs_CTD ATOMIX
profiling_direction Direction along which the section was collected, e.g., horizontal, vertical, or glide ATOMIX
fft_length Length of the Fast Fourier transform segments (in data points; note, fft_lengths_sec in seconds is optional) ATOMIX
diss_length Length of data (in data points) used for each dissipation estimate ATOMIX
overlap Length of overlap (in data points) in diss_length ATOMIX
goodman Flag for the vibration coherent noise removal using the Goodman algorithm. 0=not applied; 1=applied ATOMIX
HP_cut The high-pass filter cutoff frequency in Hz. Can be zero for no filtering. ATOMIX
conventions A comma-separated list of the conventions that are followed by the dataset. e.g., CF-1.6, ACDD-1.3, ATOMIX CF, ACDD
history Provides an audit trail for modifications to the original data; e.g., Version 1 CF, ACDD

It is highly recommended to duplicate relevant attributes at the corresponding group level. Attributes not listed in the Climate and Forecast (CF) and the Attribute Convention for Data Discovery (ACDD) standards are labeled as ATOMIX.

Optional Metadata


Attribute Name Description Convention
fft_length_sec Length of the Fast Fourier transform segments in seconds ATOMIX
diss_length_sec Dissipation estimate data length in seconds ATOMIX
overlap_sec Length of overlap (in seconds) in diss_length_sec ATOMIX
f_AA The anti-aliasing frequency in Hz ATOMIX
FOM_limit Figure of merit limit for quality assurance. Typically between 1.15 and 1.4. ATOMIX
diss_ratio_limit The limit to identify anomalously large disagreement between dissipation estimates from probes. The magnitude of the difference of the natural logarithm of two dissipation estimates should be smaller than diss_ratio_limit [math]\displaystyle{ \times \sigma_{\ln \varepsilon} }[/math]. 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 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
license the URL to a standard or specific license,

e.g, http://creativecommons.org/licenses/by/4.0/, Freely Distributed, or None

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