Level 4 data (shear probes)

From Atomix

Level 4 data include the final dissipation estimates as time series, as well as indicators for the quality and accuracy of the estimates and additional derived parameters. Each dissipation estimate in level 4 corresponds to a spectrum in the level 3 data. Consequently, the level 3 and 4 TIME dimensions are the same. Parameter EPSI_FINAL is the final dissipation rate estimate, averaged of the selected estimates (using the QC flags) at that depth.


Dimensions


Dimension short name description
TIME_SPECTRA length of the record of average times of spectral segments
N_SHEAR_SENSORS number of shear channels (shear sensors)

Required Variables


Parameter Name Standard Name Units of measurement dimensions
TIME time CF-Conventions compatible offset[math]\displaystyle{ ^c }[/math] TIME_SPECTRA
SECTION_NUMBER - TIME_SPECTRA
PSPD_REL flow_past_sensor m s-1 TIME_SPECTRA
EPSI specific_turbulent_kinetic_energy_dissipation_in_water W kg-1 [TIME_SPECTRA, N_SHEAR_SENSORS]
EPSI_FINAL specific_turbulent_kinetic_energy_dissipation_in_water W kg-1 TIME_SPECTRA
KMAX maximum_wavenumber_used_for_estimating_ turbulent_kinetic_energy_dissipation cpm [TIME_SPECTRA, N_SHEAR_SENSORS]
EPSI_FLAGS [math]\displaystyle{ ^a }[/math] dissipation_qc_flags - [TIME_SPECTRA, N_SHEAR_SENSORS]
METHOD [math]\displaystyle{ ^b }[/math] method_used_for_estimating_ turbulent_kinetic_energy_dissipation - [TIME_SPECTRA, N_SHEAR_SENSORS]

[math]\displaystyle{ ^a }[/math] Quality control coding for the final dissipation estimate.

[math]\displaystyle{ ^b }[/math] METHOD=0 for spectral integration, METHOD=1 for fitting to the inertial subrange.

[math]\displaystyle{ ^c }[/math] i.e. "Days since YYYY-MM-DDT00:00:00Z"

Optional Level 4 Variables


Parameter Name Standard Name Units of measurement dimension
PRES water_pressure dbar TIME_SPECTRA
KVISC kinematic_viscosity_of_water m2 s-1 TIME_SPECTRA
FOM figure_of_merit - [TIME_SPECTRA, N_SHEAR_SENSORS]
MAD mean_absolute_deviation - [TIME_SPECTRA, N_SHEAR_SENSORS]
VAR_RESOLVED variance_resolved - [TIME_SPECTRA, N_SHEAR_SENSORS]
KMIN minimum_wavenumber_used_for_estimating_ turbulent_kinetic_energy_dissipation cpm [TIME_SPECTRA, N_SHEAR_SENSORS]
EPSI_STD expected_standard_deviation_of_the_ logarithm_of_the_dissipation_estimate - [TIME_SPECTRA, N_SHEAR_SENSORS]



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