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| == Minimum and desirable data set ==
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| <div class="mw-collapsible" id="dataset" data-collapsetext="Collapse" data-expandtext="Expand">
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| * The absolute minimum signals and information required to estimate the rate of dissipation of kinetic energy consists of:
| | Level 1 data refers to the full resolution data in physical units, e.g. the regularly sampled time series of [[Convert the shear probe data|converted shear probe data]]. If needed, a transfer function for shear is given. Below, a table with parameters included in the level 1 data set is compiled. The data are stored as a NetCDF group with the name "L1_converted". |
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| :* a sampled shear-probe signal,
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| :* a means of determining the speed of flow past the shear probe, and
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| :* a means to estimate the temperature of the fluid so that you can determine its kinematic viscosity.
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| The sampling rate of the shear-probe signal should exceed significantly (by a factor of 2 to 4) the value of 150U, where
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| U is the speed of the flow past the shear-probe. This speed is often called the speed of profiling, even when the probe is fixed in space and the current causes fluid to flow past the shear probe. The value of 150 cpm equals the spatial resolution of the commonly used shear probe.
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| * The desirable data set
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| A far more desirable, but not absolutely necessary, set of data consists of the following.
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| :* Two or more shear probes for measurement redundancy.
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| :* Vibration sensors or accelerometers that are sensitive to the directions of sensitivity of the shear probes.
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| :* An accurate thermometer.
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| :* A pressure transducer.
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| :* A signal that can be used to estimate the speed of flow past the shear probe.
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| :* Pitch and roll sensors.
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| Most commonly available instruments carry two shear probes that are frequently oriented so that they measure orthogonal components of the shear and, thus, provide two independent estimates of the rate of dissipation that you should agree statistically.
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| </div>
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| == Level 1 data (shear probes) ==
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| Level 1 data refers to the full resolution data in physical units, e.g. the regularly sampled time series of [[Convert the shear probe data|converted shear probe data]]. If needed, a transfer function for shear is given. Below, a table with parameters included in the level 1 data set is compiled. The parameter names and definitions fit the [[NetCDF parameter]] attributes. | |
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| In the standard names, "sea_water" can be replaced with "water" if working in freshwater environments. This is specified in some entries below but not all. | | In the standard names, "sea_water" can be replaced with "water" if working in freshwater environments. This is specified in some entries below but not all. |
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| | | =Dimensions= |
| <div class="mw-collapsible" id="raw" data-collapsetext="Collapse" data-expandtext="Expand"> | | <div class="mw-collapsible mw-expand" data-collapsetext="Collapse" data-expandtext="Expand"> |
| | | <br> |
| '''Dimensions'''
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| {| class="wikitable sortable" | | {| class="wikitable sortable" |
| ! Dimension short name | | ! Dimension !! Description |
| ! description | |
| |-
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| | TIME
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| | Time axis for the microstructure sampling rate
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| |- | | |- |
| | TIME_CTD | | | TIME || length of the record from turbulence (fast) data channels |
| | Time axis for the CTD sampling rate. | |
| |- | | |- |
| | TIME_*** | | | TIME_*** <math>^a</math> || length of the record from slow data channels (if different from fast) |
| | Time axis for the *** sensor sampling rate | |
| |- | | |- |
| |N_SHEAR_SENSORS | | |N_SHEAR_SENSORS ||number of shear channels (shear sensors) |
| |number of shear channel | |
| |- | | |- |
| |N_***_SENSORS | | |N_***_SENSORS <math>^b</math> ||number of *** channel (sensors) |
| |number of *** channel (e.g., N_VIB_SENSORS, N_ACC_SENSORS) | |
| |- | | |- |
| |} | | |} |
| | <math>^a</math> Typically TIME is assumed for the fast-sampled microstructure channels. Use, e.g., TIME_SLOW or TIME_CTD for slower sampled channels such as CTD and tilt sensors. If the application requires different time stamps for different sensors, this can be utilized like TIME_PITCH, TIME_ACC etc. |
| | <br> |
| | <math>^b</math> Please use these examples for related sensors:<br> |
| | N_VIB_SENSORS for vibration (piezo-acceleration) sensors, <br> |
| | N_ACC_SENSORS for vibration acceleration sensors, <br> |
| | N_GRADT_SENSORS for thermistors, <br> |
| | N_GRADC_SENSORS for microconductivity sensors. <br> |
| | </div> |
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| | =Variables= |
| | <div class="mw-collapsible mw-expand" data-collapsetext="Collapse" data-expandtext="Expand"> |
| | <br> |
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| '''Required Variables'''
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| {| class="wikitable sortable" | | {| class="wikitable sortable" |
| |- | | |- |
| ! Parameter Name !! Standard Name !! Units of measurement !! dimension | | ! Variable Name !! Req.<math>^a</math> !! Standard Name !! Unit !! Dimensions |
| |- | | |- |
| | TIME || time || Days since YYYY-MM-DDT00:00:00Z || TIME | | | TIME || R || time || [http://cfconventions.org/cf-conventions/cf-conventions CF-Convention]<math>^b</math> || TIME |
| |- | | |- |
| | SHEAR || sea_water_velocity_shear<br /> (or water_velocity_shear) || s-1 || [TIME, N_SHEAR_SENSORS] | | | SHEAR || R || [sea]<math>^c</math>_water_velocity_shear || s-1 || TIME, N_SHEAR_SENSORS |
| |}
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| '''Optional Level 1 Variables'''
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| {| class="wikitable sortable"
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| |- | | |- |
| ! Parameter Name !! Standard Name !! Units of measurement !! dimension
| | | PSPD_REL || HR|| platform_speed_wrt_[sea]<math>^c</math>_water || m s-1 || TIME |
| |- | | |- |
| | PSPD_REL || platform_speed_wrt_sea_water || m s-1 || TIME (or TIME_SLOW or TIME_CTD) | | | VIB || HR || platform_vibration || - || TIME, N_VIB_SENSORS |
| |- | | |- |
| | VIB || platform_vibration || NA || [TIME_VIB, N_VIB_SENSORS] | | | PRES || HR || [sea]<math>^c</math>_water_pressure|| dbar || TIME |
| |- | | |- |
| | ACC || platform_acceleration || m s-2 || [TIME_ACCEL, N_ACC_SENSORS] | | | TEMP || HR || [sea]<math>^c</math>_water_temperature || degree_Celsius || TIME, N_T_SENSORS |
| |- | | |- |
| | TEMP || sea_water_temperature<br /> (water_temperature) || degree_Celsius || [TIME_CTD, N_T_SENSORS | | | ACC || O || platform_acceleration || m s-2 || TIME, N_ACC_SENSORS |
| |- | | |- |
| | CNCD || sea_water_electrical_conductivity<br /> (water_electrical_conductivity) || S m-1 || [TIME_CTD, N_C_SENSORS] | | | CNDC || O || [sea]<math>^c</math>_water_electrical_conductivity || S m-1 || TIME_CTD, N_C_SENSORS |
| |- | | |- |
| | GRADT || temperature_gradient || || [TIME, N_GRADT_SENSORS] | | | GRADT || O || derivative_of_[sea]<math>^c</math>_water_temperature_wrt_<math>^{*d}</math>|| degree_Celcius m-1 || TIME, N_GRADT_SENSORS |
| |- | | |- |
| | GRADC || conductivity_gradient || || [TIME, N_GRADC_SENSORS] | | | GRADC || O || derivative_of_[sea]<math>^c</math>_water_conductivity_wrt_<math>^{*d}</math> || - || TIME, N_GRADC_SENSORS |
| |- | | |- |
| | PITCH || platform_pitch_angle || degree || TIME (or TIME_SLOW or TIME_CTD) | | | PITCH || O || platform_pitch_angle || degree || TIME |
| |- | | |- |
| | ROLL || platform_roll_angle || degree || TIME (or TIME_SLOW or TIME_CTD) | | | ROLL || O || platform_roll_angle || degree || TIME |
| |} | | |} |
| | | <math>^a</math>: Code for the requirement of variable, R: Required, HR: Highly recommended, O: Optional |
| | <br><math>^b</math>: Unit and offset need to be compatible with the Climate and Forecast (CF)-convention |
| | <br><math>^c</math>: User can choose between water or sea_water depending on the environment |
| | <br><math>^d</math>: wrt_x or wrt_s; spatial derivative. Typically derived from the rate of change of temperature and divided by the profiling speed. |
| </div> | | </div> |
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| ------ | | ------ |
| return to [[Dataset requirements for shear probes]]. | | return to [[Dataset requirements for shear probes]] <br> |
| | | go to next: [[Level 2 data (shear probes)| Level 2 data]]. |
| <div class="mw-collapsible mw-collapsed" id="archive" data-collapsetext="Collapse archive" data-expandtext="Expand archive">
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| Numbers in the last column indicate:
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| : required=1 are the absolute minimum parameter required for a data set
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| : required=2 are preferred/recommended parameter
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| : required=3 are optional parameter
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| {| class="wikitable sortable"
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| |-
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| ! Parameter Name !! CF parameter !! Standard Name !! Units of measurement !! dimension !! required
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| |-
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| | TIME || 1 || time || days since YYYY-MM-DDT00:00:00Z || TIME || 1
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| |-
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| | SHEAR || 0 || water_velocity_shear || s-1 || [TIME, N_SHEAR_SENSORS] || 1
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| |-
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| | PRES || 1<br /> 0|| sea_water_pressure<br /> water_pressure || dbar || TIME_CTD || 1,2
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| |-
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| | VIB || 0 || platform_vibration || NA || [TIME_VIB, N_VIB_SENSORS] || 2
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| |-
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| | ACC || 0 || platform_acceleration || m s-2 || [TIME_ACCEL, n_acc_sensors] || 2
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| |-
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| | TEMP || 1<br /> (0) || sea_water_temperature<br /> (water_temperature) || degree_Celsius || [TIME_CTD,n_T_sensors] || 2
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| |-
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| | CNCD || 1<br /> (0) || sea_water_electrical_conductivity<br /> (water_electrical_conductivity) || S m-1 || [TIME_CNCD,n_C_sensors] || 2
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| |-
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| | GRADT || || temperature_gradient || || [TIME_GRADT, n_gradT_sensors] || 3
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| |-
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| | GRADC || || conductivity_gradient || || [TIME_GRADC, n_gradC_sensors] || 3
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| |-
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| | PITCH || 1 || platform_pitch_angle || degree || [TIME_PITCH] || 2
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| |-
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| | ROLL || 1 || platform_roll_angle || degree || [TIME_ROLL] || 2
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| |}
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| </div>
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| [[Category: Shear probes]] | | [[Category: Shear probes]] |
Level 1 data refers to the full resolution data in physical units, e.g. the regularly sampled time series of converted shear probe data. If needed, a transfer function for shear is given. Below, a table with parameters included in the level 1 data set is compiled. The data are stored as a NetCDF group with the name "L1_converted".
In the standard names, "sea_water" can be replaced with "water" if working in freshwater environments. This is specified in some entries below but not all.
Dimensions
| Dimension |
Description
|
| TIME |
length of the record from turbulence (fast) data channels
|
| TIME_*** [math]\displaystyle{ ^a }[/math] |
length of the record from slow data channels (if different from fast)
|
| N_SHEAR_SENSORS |
number of shear channels (shear sensors)
|
| N_***_SENSORS [math]\displaystyle{ ^b }[/math] |
number of *** channel (sensors)
|
[math]\displaystyle{ ^a }[/math] Typically TIME is assumed for the fast-sampled microstructure channels. Use, e.g., TIME_SLOW or TIME_CTD for slower sampled channels such as CTD and tilt sensors. If the application requires different time stamps for different sensors, this can be utilized like TIME_PITCH, TIME_ACC etc.
[math]\displaystyle{ ^b }[/math] Please use these examples for related sensors:
N_VIB_SENSORS for vibration (piezo-acceleration) sensors,
N_ACC_SENSORS for vibration acceleration sensors,
N_GRADT_SENSORS for thermistors,
N_GRADC_SENSORS for microconductivity sensors.
Variables
| Variable Name |
Req.[math]\displaystyle{ ^a }[/math] |
Standard Name |
Unit |
Dimensions
|
| TIME |
R |
time |
CF-Convention[math]\displaystyle{ ^b }[/math] |
TIME
|
| SHEAR |
R |
[sea][math]\displaystyle{ ^c }[/math]_water_velocity_shear |
s-1 |
TIME, N_SHEAR_SENSORS
|
| PSPD_REL |
HR |
platform_speed_wrt_[sea][math]\displaystyle{ ^c }[/math]_water |
m s-1 |
TIME
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| VIB |
HR |
platform_vibration |
- |
TIME, N_VIB_SENSORS
|
| PRES |
HR |
[sea][math]\displaystyle{ ^c }[/math]_water_pressure |
dbar |
TIME
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| TEMP |
HR |
[sea][math]\displaystyle{ ^c }[/math]_water_temperature |
degree_Celsius |
TIME, N_T_SENSORS
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| ACC |
O |
platform_acceleration |
m s-2 |
TIME, N_ACC_SENSORS
|
| CNDC |
O |
[sea][math]\displaystyle{ ^c }[/math]_water_electrical_conductivity |
S m-1 |
TIME_CTD, N_C_SENSORS
|
| GRADT |
O |
derivative_of_[sea][math]\displaystyle{ ^c }[/math]_water_temperature_wrt_[math]\displaystyle{ ^{*d} }[/math] |
degree_Celcius m-1 |
TIME, N_GRADT_SENSORS
|
| GRADC |
O |
derivative_of_[sea][math]\displaystyle{ ^c }[/math]_water_conductivity_wrt_[math]\displaystyle{ ^{*d} }[/math] |
- |
TIME, N_GRADC_SENSORS
|
| PITCH |
O |
platform_pitch_angle |
degree |
TIME
|
| ROLL |
O |
platform_roll_angle |
degree |
TIME
|
[math]\displaystyle{ ^a }[/math]: Code for the requirement of variable, R: Required, HR: Highly recommended, O: Optional
[math]\displaystyle{ ^b }[/math]: Unit and offset need to be compatible with the Climate and Forecast (CF)-convention
[math]\displaystyle{ ^c }[/math]: User can choose between water or sea_water depending on the environment
[math]\displaystyle{ ^d }[/math]: wrt_x or wrt_s; spatial derivative. Typically derived from the rate of change of temperature and divided by the profiling speed.
return to Dataset requirements for shear probes
go to next: Level 2 data.
