NetCDF synoptic data at multiple locations
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Short Description
Synoptic data for multiple locations are described. A few examples for typical variables are shown.
Additional Descriptions
- NetCDF multiple locations: coordinates as well as coordinate transformation for multiple locations.
- NetCDF time coordinate: coordinate variable time.
- NetCDF vertical coordinate: time and space dependent vertical coordinate variable.
Version Discrete Sampling Geometry timeSeriesProfile
Data for several individual locations are stored in a netCDF file in accordance with the concept of a Discrete Sampling Geometry with featureType=timeSeriesProfile. An example (output from NCDUMP) for geometry as well as data is shown in .
Data without Z-Dependence
Water level typically depends on time and location. But it is independent from the z-coordinate. Water level is therefore a good example for a geophysical variable without z-dependence.
float Mesh0_node_Wasserstand_2d(nMesh0_data_time, nMesh0_node) ;
- :long_name = "Wasserstand [ node ]" ;
- :units = "m" ;
- :name_id = 3 ;
- :_FillValue = 1.e+31f ;
- :ancillary_variables = "Mesh0_node_Gesamtwassertiefe_2d" ;
- :cell_measures = "area: Mesh0_node_Wasserflaeche_2d" ;
- :cell_methods = "nMesh0_data_time: point nMesh0_node: mean" ;
- :comment = "ancillary variables may be used ..." ;
- :coordinates = "Mesh0_node_lon Mesh0_node_lat Mesh0_node_x Mesh0_node_y Mesh0_node_long_name" ;
- :grid_mapping = "Mesh0_crs" ;
- :standard_name = "sea_surface_height" ;
Remarks:
- Invalid data may be present (see _FillValue).
- Auxiliary variable (see ancillary_variables) Mesh0_node_Gesamtwassertiefe_2d may be used during processing (data analysis and visualization) to neglect data for locations with very shallow water.
- Water level is synoptic and (in our case) an area mean value (see cell_methods).
- Variable Mesh0_node_Wasserflaeche_2d contains the relevant area for area mean values.
- Label coordinate variable Mesh0_node_long_name can be used for selection of locations (see coordinates).
Data with Z-Dependence
Salinity typically depends on time, location and depth. In our case the z-coordinate reflects the center of water mass for the respective volume. Salinity is therefore a good example for a geophysical variable with z-dependence.
float Mesh0_node_Salzgehalt_2d(nMesh0_data_time, nMesh0_layer_2d, nMesh0_node) ;
- :long_name = "Salzgehalt [ node ]" ;
- :units = "1e-3" ;
- :name_id = 5 ;
- :_FillValue = 1.e+31f ;
- :ancillary_variables = "Mesh0_node_Gesamtwassertiefe_2d" ;
- :cell_measures = "volume: Mesh0_node_Wasservolumen_2d area: Mesh0_node_Wasserflaeche_2d" ;
- :cell_methods = "nMesh0_data_time: point nMesh0_layer_2d: mean nMesh0_node: mean" ;
- :comment = "ancillary variables may be used ..." ;
- :coordinates = "Mesh0_node_lon Mesh0_node_lat Mesh0_node_x Mesh0_node_y Mesh0_node_z_node_2d Mesh0_node_long_name" ;
- :grid_mapping = "Mesh0_crs" ;
- :standard_name = "sea_water_salinity" ;
Remarks:
- Invalid data may be present (see _FillValue).
- Auxiliary variable (see ancillary_variables) Mesh0_node_Gesamtwassertiefe_2d may be used during processing (data analysis and visualization) to neglect data for locations with very shallow water.
- Salinity is synoptic and (in our case) an volume mean value (see cell_methods).
- Variable Mesh0_node_Wasservolumen_2d contains the relevant volume for volume mean values.
- With additional help of Mesh0_node_Wasserflaeche_2d exact values for salt mass per area can be derived.
- Label coordinate variable Mesh0_node_long_name can be used for selection of locations (see coordinates).
Data for several Fractions
Suspended sediment concentration typically depends on time, location and depth. Also different sediment fractions nMesh0_suspension_classes can be available. In our case the z-coordinate reflects the center of water mass for the respective volume. Suspended sediment concentration is therefore a good example for a geophysical variable with dependence on a label coordinate variable for one or more fractions.
float Mesh0_node_Schwebstoffgehalt_2d(nMesh0_data_time, nMesh0_suspension_classes, nMesh0_layer_2d, nMesh0_node) ;
- :long_name = "Schwebstoffgehalt [ node ]" ;
- :units = "kg m-3" ;
- :name_id = 7 ;
- :_FillValue = 1.e+31f ;
- :ancillary_variables = "Mesh0_node_Gesamtwassertiefe_2d" ;
- :cell_measures = "volume: Mesh0_node_Wasservolumen_2d area: Mesh0_node_Wasserflaeche_2d" ;
- :cell_methods = "nMesh0_data_time: point nMesh0_suspension_classes: point nMesh0_layer_2d: mean nMesh0_node: mean" ;
- :comment = "ancillary variables may be used ..." ;
- :coordinates = "Mesh0_node_lon Mesh0_node_lat Mesh0_node_x Mesh0_node_y Mesh0_node_z_node_2d Mesh0_node_long_name Mesh0_Schwebstoffklassen_2d" ;
- :grid_mapping = "Mesh0_crs" ;
- :standard_name = "concentration_of_suspended_matter_in_sea_water" ;
Remarks:
- Invalid data may be present (see _FillValue).
- Auxiliary variable (see ancillary_variables) Mesh0_node_Gesamtwassertiefe_2d may be used during processing (data analysis and visualization) to neglect data for locations with very shallow water.
- Suspended sediment concentration is synoptic and (in our case) an volume mean value (see cell_methods).
- Variable Mesh0_node_Wasservolumen_2d contains the relevant volume for volume mean values.
- With additional help of Mesh0_node_Wasserflaeche_2d exact values for suspended sediment mass per area can be derived.
- Label coordinate variable Mesh0_node_long_name can be used for selection of locations (see coordinates).
- Label coordinate variable Mesh0_Schwebstoffklassen_2d can be used for selection of fractions (see coordinates).
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