Level 4 data (velocity profilers)
| Page status: Ready for review | |
|---|---|
| Author(s): | Cynthia |
| Reviewer(s): | |
| Comment: | |
This will dictate the data required at the final processing level, where we store the estimated dissipation estimates [math]\displaystyle{ \varepsilon }[/math] along with quality metrics.
Only a few attributes for each variable are listed since the page's purpose is to describe the information layout within each NetCDF file. Please refer to the complete list for the additional attributes related to each variable (e.g., units, bounds, cell_methods).
Dimensions
| Short name | Standard name | Dimensions | Comments |
|---|---|---|---|
| TIME | time | TIME | Units in Days since 1950-01-01T00:00:00Z. Provide bounds attribute to designate the variable containing the limits of each segment (see CF-compliant example). |
| Z_DIST | distance_from_sensor_along_vertical | Z_DIST | bin centre distance (in meters) from the transducer along the instrument's vertical axis |
| N_BEAM | unique_identifier_for_each_beam | N_BEAM | Array of 1 to number of beams (3 to 5 typically) |
Variables
| Short name | Standard name | Dimensions | Comment |
|---|---|---|---|
| EPSI | specific_turbulent_kinetic_energy_dissipation
_in_sea_water |
TIME, Z_DIST, N_BEAM | Dissipation rate of turbulent kinetic energy per unit mass of water [W/kg] estimated from individual beams. |
| EPSI_FINAL | specific_turbulent_kinetic_energy_dissipation
_in_sea_water |
TIME, Z_DIST | Final (beam-averaged) dissipation rate of turbulent kinetic energy per unit mass of water [W/kg]. best to state cell_methods attribute to indicate what was averaged e.g., "cell_methods= N_BEAM:mean" for averages across beams. |
| C2 | constant_used_in_the_second_order_structure_function | Scalar [1 value] | This constant appears when estimating the dissipation rate of turbulent kinetic energy from the regression coefficients. provide link to equation |
| Quality-control metrics | |||
| EPSI_FLAGS | specific_turbulent_kinetic_energy_dissipation_
in_sea_water_status_flag |
TIME, Z_DIST, N_BEAM | To be linked, when boolean flags defined |
| EPSI_CI_HIGH | specific_turbulent_kinetic_energy_dissipation_
in_sea_water_high_confidence_limit |
TIME, Z_DIST, N_BEAM | Specify how error was computed. |
| EPSI_CI_LOW | specific_turbulent_kinetic_energy_dissipation_
in_sea_water_low_confidence_limit |
TIME, Z_DIST, N_BEAM | Specify how error was computed. |
| R_MAX | max-mum_separation_distance_for_DLL_regression | TIME, Z_DIST, N_BEAM | help! |
| REGRESSION_COEFF_A0 | structure_function_regression_intercept | TIME, Z_DIST, N_BEAM | help! |
| REGRESSION_COEFF_A1 | structure_function_regression_coefficient for_r^2/3 | TIME, Z_DIST, N_BEAM | help! |
| REGRESSION_R2 | regression_goodness_of_fit_adjusted_for_number_of_terms | TIME, Z_DIST, N_BEAM | help! |
| REGRESSION_N | structure_function_regression_number_of_observations | TIME, Z_DIST, N_BEAM | Note the CF-compliant standard name modifier "number_of_observations" |
| Optional dimensions for 5-beam ADCP | |||
| Enter variables here or create a footnote (note that N_BEAM disappears as a dimension for the 5th beam) | TIME, R_DIST5 | ||
|
[math]\displaystyle{ \dagger\dagger }[/math] Variable required only when measuring in bursts e.g., 18 min of continuous measurements every hour. | |||
Group attributes (metadata)
This section describes attributes that may provide additional information about how the data was processed and manipulated at this stage.
| Attribute name | Purpose | Suggested content |
|---|---|---|
| processing_level | Boilerplate about the content of the NetCDF group. |
|
| dll_fitting_method | statistical technique used for fitting the spectra. | Examples include:
???? |
| comment (optional) | Any additional information pertinent to other users who test their algorithms against the file. |
Return to Level 3 structure function
Go back to the beginning Dataset requirements for ADCP structure function
