Level 4 data (velocity point-measurements)

Page status: Draft
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

The number of velocity instruments (N_VEL_INSTRUMENT) is here for completeness, but the benchmarks examples will have measurements only from one instrument stored.

Short name	Standard name	Dimensions	Comments
TIME	time	TIME	Units in Days since 1950-01-01T00:00:00Z, time-centred. Provide "bounds" attribute to designate the variable containing the limits of each segment (see CF-compliant example).
N_VEL_COMPONENT	unique_identifier_for_each_velocity_component	N_VEL_COMPONENT	Maximum of 3 for u,v, w (east, north, up) velocities
Optional variables [math]\displaystyle{ \ddagger }[/math]
N_VEL_INSTRUMENT	unique_identifier_for_each_velocity_instrument	N_VEL_INSTRUMENT	Required only if storing multiple synchronized instruments in the same file

Variables

Short name	Standard name	Dimensions	Comment
EPSI	specific_turbulent_kinetic_energy_dissipation _in_water	TIME, N_VEL_COMPONENT, N_VEL_INSTRUMENT	Dissipation rate of turbulent kinetic energy per unit mass of water [W/kg] estimated from each velocity component.
EPSI_FINAL	specific_turbulent_kinetic_energy_dissipation _in_water	TIME, N_VEL_INSTRUMENT	Final dissipation rate of turbulent kinetic energy per unit mass of water. Typically the vertical component, unless anisotropy precludes from its use. } Return to: Level 3 spectra