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NetCDF Synoptische Daten im unstrukturierten Gitter

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Version vom 10. September 2010, 11:59 Uhr von imported>Lang Guenther (→‎Knoten)

Kurze Beschreibung

Synoptische Daten für alle staggered data Positionen eines (klassischen) unstrukturierten Gitters, welches typischer Weise aus Drei- und Vierecken aufgebaut ist.

Weitere Beschreibungen

Dimensionen

Informationen für das HN-Verfahren

Kennzeichnung offener und geschlossener Kanten

Kennzeichnung von Positionen für die Randwertsteuerung

Text fehlt noch.

Datenkompression

Auf Grund der Verwendung von z-Schichten sind, z. B. über jedem Polygon, in Abhängigkeit von der Wassertiefe unterschiedlich viele (aktive) Berechnungszellen vorhanden. Zur Reduktion der Größe der Ergebnisdatensätze werden verschiedene Dimensionen in einer komprimierten Dimension zusammengefasst. Dauerhaft fehlende Daten werden daher erst gar nicht in der Datei abgespeichert. Dies reduziert bei drei-dimensionalen Simulationen mit z-Schichten den Speicheraufwand typischer Weise um 60 bis 80 Prozent.

Komprimierte Daten an Knoten

Komprimierte Daten auf Kanten

Komprimierte Daten in Polygonen

Gewichte

Gewichte werden insbesondere im Postprocessing benötigt, um abgeleitete Daten korrekt berechnen zu können, falls die hierfür relevanten Gewichtsfaktoren, z. B. Flächen oder Volumina, nicht in einfacher Weise aus den Koordinaten abgeleitet werden können. Die Verwendung von Gewichten bringt daher eine große Sicherheit in die späteren Weiterverarbeitung der Daten. Beispiele für abgeleitete Daten sind Tiefenmittelwerte, Durchflüsse, räumliche Mittelwerte, Massensummen usw.

Aktuelle (zeitvariable) Topografie

Es werden nur die Angaben für zeitvariable Topografie gemacht. Bei stationärer Topografie entfällt die Dimension time.

Knoten

Kanten

double Mesh2_edge_depth(time,nMesh2_edge) ;
Mesh2_edge_depth:standard_name = "sea_floor_depth_below_geoid" ;
Mesh2_edge_depth:long_name = "sea floor depth for 2D mesh edges" ;
Mesh2_edge_depth:units = "m" ;
Mesh2_edge_depth:coordinates = "Mesh2_edge_lon Mesh2_edge_lat" ;
Mesh2_edge_depth:_FillValue = fillvalue ;
Mesh2_edge_depth:valid_range = valid minimum, valid maximum ;
Mesh2_edge_depth:cell_methods = "nMesh2_edge: mean" ; \\ depth is constant along edge
Mesh2_poly_depth:cell_measures = "length: Mesh2_poly_max_length_2d" ;
Mesh2_edge_depth:grid_mapping = "crs"

Polygone

double Mesh2_poly_depth(time,nMesh2_poly) ;
Mesh2_poly_depth:standard_name = "sea_floor_depth_below_geoid" ;
Mesh2_poly_depth:long_name = "sea floor depth for 2D mesh polygons" ;
Mesh2_poly_depth:units = "m" ;
Mesh2_poly_depth:coordinates = "Mesh2_poly_lon Mesh2_poly_lat" ;
Mesh2_poly_depth:_FillValue = fillvalue ;
Mesh2_poly_depth:valid_range = valid minimum, valid maximum ;
Mesh2_poly_depth:cell_methods = "nMesh2_poly: mean" ; \\ depth is constant within polygon
Mesh2_poly_depth:cell_measures = "area: Mesh2_poly_max_area_2d" ;
Mesh2_poly_depth:grid_mapping = "crs"

Maximal zulässige Tiefe

  • Vollständig analog zu Aktuelle Tiefe vorgehen, jedoch ohne Dimension time.
  • Vorschlag für die Namensgebung:
    1. Knoten: "Mesh2_node_max_depth(nMesh2_node)" ;
    2. Kanten: "Mesh2_edge_max_depth(nMesh2_edge)" ;
    3. Polygone: "Mesh2_poly_max_depth(nMesh2_poly)" .

Wasserstand

Typischer Weise liegt der Wasserstand entweder (punktweise) am Knoten oder konstant im Polygon vor.

Knoten

double Mesh2_node_water_level(time,nMesh2_node) ;
Mesh2_node_water_level:standard_name = "sea_surface_height_above_geoid" ;
Mesh2_node_water_level:long_name = "water level for 2D mesh nodes" ;
Mesh2_node_water_level:units = "m" ;
Mesh2_node_water_level:coordinates = "Mesh2_node_lon Mesh2_node_lat" ;
Mesh2_node_water_level:_FillValue = fillvalue ;
Mesh2_node_water_level:valid_range = valid minimum, valid maximum ;
Mesh2_node_water_level:cell_methods = "nMesh2_node: point" ; \\ pointwise data
Mesh2_node_water_level:grid_mapping = "crs" ;

Polygon

double Mesh2_poly_water_level(time,nMesh2_poly) ;
Mesh2_poly_water_level:standard_name = "sea_surface_height_above_geoid" ;
Mesh2_poly_water_level:long_name = "water level for 2D mesh polygons" ;
Mesh2_poly_water_level:units = "m" ;
Mesh2_poly_water_level:coordinates = "Mesh2_poly_lon Mesh2_poly_lat" ;
Mesh2_poly_water_level:_FillValue = fillvalue ;
Mesh2_poly_water_level:valid_range = valid minimum, valid maximum ;
Mesh2_poly_water_level:cell_methods = "nMesh2_poly: mean" \\ mean value within polygon
Mesh2_poly_water_level:cell_measures = "area: Mesh2_poly_wet_area_2d" ;
Mesh2_poly_water_level:grid_mapping = "crs" ;

Tiefengemittelter Salzgehalt

Typischer Weise liegt der Salzgehalt entweder (punktweise) über Knoten oder über Polygonen vor.

Knoten

double Mesh2_node_salinity_2d(time,nMesh2_node) ;
Mesh2_node_salinity_2d:standard_name = "sea_water_salinity" ;
Mesh2_node_salinity_2d:long_name = "salinity for 2D mesh nodes, depth averaged" ;
Mesh2_node_salinity_2d:units = "0.001" ;
Mesh2_node_salinity_2d:coordinates = "Mesh2_node_lon Mesh2_node_lat" ;
Mesh2_node_salinity_2d:_FillValue = fillvalue ;
Mesh2_node_salinity_2d:valid_range = valid minimum, valid maximum ;
Mesh2_node_salinity_2d:cell_methods = "nMesh2_node: mean" ;
Mesh2_node_salinity_2d:cell_measures = "length: Mesh2_node_water_depth_2d" \\ depth averaged
Mesh2_node_salinity_2d:grid_mapping = "crs" ;

Polygone

double Mesh2_poly_salinity_2d(time,nMesh2_poly) ;
Mesh2_poly_salinity_2d:standard_name = "sea_water_salinity" ;
Mesh2_poly_salinity_2d:long_name = "salinity for 2D mesh nodes, depth averaged" ;
Mesh2_poly_salinity_2d:units = "0.001" ;
Mesh2_poly_salinity_2d:coordinates = "Mesh2_poly_lon Mesh2_poly_lat" ;
Mesh2_poly_salinity_2d:_FillValue = fillvalue ;
Mesh2_poly_salinity_2d:valid_range = valid minimum, valid maximum ;
Mesh2_poly_salinity_2d:cell_methods = "nMesh2_poly: mean" ;
Mesh2_poly_salinity_2d:cell_measures = "volume: Mesh2_poly_water_volume_2d" ; \\ volume averaged
Mesh2_poly_salinity_2d:grid_mapping = "crs" ;

Tiefenstrukturierter Salzgehalt

Typischer Weise liegt der Salzgehalt entweder (punktweise) über Knoten oder über Polygonen vor.

Knoten

double Mesh2_node_salinity_3d(time,nMesh2_vedge) ; \\ compression used
Mesh2_node_salinity_3d:standard_name = "sea_water_salinity" ;
Mesh2_node_salinity_3d:long_name = "salinity for 2D mesh nodes, vertically structured" ;
Mesh2_node_salinity_3d:units = "0.001" ;
Mesh2_node_salinity_3d:coordinates = "Mesh2_node_lon Mesh2_node_lat" ;
Mesh2_node_salinity_3d:_FillValue = fillvalue ;
Mesh2_node_salinity_3d:valid_range = valid minimum, valid maximum ;
Mesh2_node_salinity_3d:cell_methods = "nMesh2_vedge: mean" ;
Mesh2_node_salinity_3d:cell_measures = "length: Mesh2_node_water_depth_3d" \\ depth averaged
Mesh2_node_salinity_3d:grid_mapping = "crs" ;

Polygone

double Mesh2_poly_salinity_3d(time,nMesh2_cell) ;
Mesh2_poly_salinity_3d:standard_name = "sea_water_salinity" ;
Mesh2_poly_salinity_3d:long_name = "salinity for 2D mesh polygons, vertically structured" ;
Mesh2_poly_salinity_3d:units = "0.001" ;
Mesh2_poly_salinity_3d:coordinates = "Mesh2_poly_lon Mesh2_poly_lat" ;
Mesh2_poly_salinity_3d:_FillValue = fillvalue ;
Mesh2_poly_salinity_3d:valid_range = valid minimum, valid maximum ;
Mesh2_poly_salinity_3d:cell_methods = "nMesh2_cell: mean" ;
Mesh2_poly_salinity_3d:cell_measures = "volume: Mesh2_poly_water_volume_3d" ; \\ volume averaged
Mesh2_poly_salinity_3d:grid_mapping = "crs" ;

Tiefengemittelte Strömungsgeschwindigkeit

Knoten

double Mesh2_node_velocity_x_2d(time,nMesh2_node) ;
Mesh2_node_velocity_x_2d:standard_name = "sea_water_x_velocity" ; \\ or better eastward_sea_water_velocity
Mesh2_node_velocity_x_2d:long_name = "current velocity in x-direction for 2D mesh nodes, depth integrated" ;
Mesh2_node_velocity_x_2d:units = "m s-1" ;
Mesh2_node_velocity_x_2d:coordinates = "Mesh2_node_lon Mesh2_node_lat" ;
Mesh2_node_velocity_x_2d:_FillValue = fillvalue ;
Mesh2_node_velocity_x_2d:valid_range = valid minimum, valid maximum ;
Mesh2_node_velocity_x_2d:cell_methods = "nMesh2_node: mean" ;
Mesh2_node_velocity_x_2d:cell_measures = "length: Mesh2_node_water_depth_2d" ;
Mesh2_node_velocity_x_2d:grid_mapping = "crs"
Bemerkung: y-Komponente sea_water_y_velocity (northward_sea_water_velocity) analog.

Kanten

double Mesh2_edge_velocity_x_2d(time,nMesh2_edge) ;
Mesh2_edge_velocity_x_2d:standard_name = "sea_water_x_velocity" ; \\ or better eastward_sea_water_velocity
Mesh2_edge_velocity_x_2d:long_name = "current velocity in x-direction for 2D mesh edges, depth integrated" ;
Mesh2_edge_velocity_x_2d:units = "m s-1" ;
Mesh2_edge_velocity_x_2d:coordinates = "Mesh2_edge_lon Mesh2_edge_lat" ;
Mesh2_edge_velocity_x_2d:_FillValue = fillvalue ;
Mesh2_edge_velocity_x_2d:valid_range = valid minimum, valid maximum ;
Mesh2_edge_velocity_x_2d:cell_methods = "nMesh2_edge: mean" ;
Mesh2_edge_velocity_x_2d:cell_measures = "area: Mesh2_edge_flow_area_2d" ;
Mesh2_edge_velocity_x_2d:grid_mapping = "crs"
Bemerkung: y-Komponente sea_water_y_velocity (northward_sea_water_velocity) analog.
double Mesh2_edge_velocity_n_2d(time,nMesh2_edge) ;
Mesh2_edge_velocity_n_2d:standard_name = "???" ;
Mesh2_edge_velocity_n_2d:long_name = "normal current velocity for 2D mesh edges, depth integrated" ;
Mesh2_edge_velocity_n_2d:units = "m s-1" ;
Mesh2_edge_velocity_n_2d:coordinates = "Mesh2_edge_lon Mesh2_edge_lat" ;
Mesh2_edge_velocity_n_2d:_FillValue = fillvalue ;
Mesh2_edge_velocity_n_2d:valid_range = valid minimum, valid maximum ;
Mesh2_edge_velocity_n_2d:cell_methods = "nMesh2_edge: mean" ;
Mesh2_edge_velocity_n_2d:cell_measures = "area: Mesh2_edge_flow_area_2d" ;
Mesh2_edge_velocity_n_2d:grid_mapping = "crs"

Tiefenstrukturierte Strömungsgeschwindigkeit

Knoten

double Mesh2_node_velocity_x_3d(time,nMesh2_vedge) ; \\ compression used
Mesh2_node_velocity_x_3d:standard_name = "sea_water_x_velocity" ; \\ or better eastward_sea_water_velocity
Mesh2_node_velocity_x_3d:long_name = "current velocity in x-direction for 2D mesh nodes, vertically structured" ;
Mesh2_node_velocity_x_3d:units = "m s-1" ;
Mesh2_node_velocity_x_3d:coordinates = "Mesh2_node_lon Mesh2_node_lat" ;
Mesh2_node_velocity_x_3d:_FillValue = fillvalue ;
Mesh2_node_velocity_x_3d:valid_range = valid minimum, valid maximum ;
Mesh2_node_velocity_x_3d:cell_methods = "nMesh2_vedge: mean" ;
Mesh2_node_velocity_x_3d:cell_measures = "length: Mesh2_node_water_depth_3d" ;
Mesh2_node_velocity_x_3d:grid_mapping = "crs"
Bemerkung: y-Komponente sea_water_y_velocity (northward_sea_water_velocity) analog.
double Mesh2_node_velocity_z_3d(time,nMesh2_vedge) ; \\ compression used
Mesh2_node_velocity_z_3d:standard_name = "upward_sea_water_velocity" ;
Mesh2_node_velocity_z_3d:long_name = "current velocity in z-direction for 2D mesh nodes, vertically structured" ;
Mesh2_node_velocity_z_3d:units = "m s-1" ;
Mesh2_node_velocity_z_3d:coordinates = "Mesh2_node_lon Mesh2_node_lat" ;
Mesh2_node_velocity_z_3d:_FillValue = fillvalue ;
Mesh2_node_velocity_z_3d:valid_range = valid minimum, valid maximum ;
Mesh2_node_velocity_z_3d:cell_methods = "nMesh2_vedge: mean" ;
Mesh2_node_velocity_z_3d:cell_measures = "length: Mesh2_node_water_depth_3d" ;
Mesh2_node_velocity_z_3d:grid_mapping = "crs"

Kanten

double Mesh2_edge_velocity_x_3d(time,nMesh2_face) ;
Mesh2_edge_velocity_x_3d:standard_name = "sea_water_x_velocity" ; \\ or better eastward_sea_water_velocity
Mesh2_edge_velocity_x_3d:long_name = "current velocity in x-direction for 2D mesh edges, verticalls structured" ;
Mesh2_edge_velocity_x_3d:units = "m s-1" ;
Mesh2_edge_velocity_x_3d:coordinates = "Mesh2_edge_lon Mesh2_edge_lat" ;
Mesh2_edge_velocity_x_3d:_FillValue = fillvalue ;
Mesh2_edge_velocity_x_3d:valid_range = valid minimum, valid maximum ;
Mesh2_edge_velocity_x_3d:cell_methods = "nMesh2_face: mean" ;
Mesh2_edge_velocity_x_3d:cell_measures = "area: Mesh2_edge_flow_area_3d" ;
Mesh2_edge_velocity_x_3d:grid_mapping = "crs"
Bemerkung: y-Komponente sea_water_y_velocity (northward_sea_water_velocity) analog.
double Mesh2_edge_velocity_z_3d(time,nMesh2_face) ; \\ compression used
Mesh2_edge_velocity_z_3d:standard_name = "upward_sea_water_velocity" ;
Mesh2_edge_velocity_z_3d:long_name = "current velocity in z-direction for 2D mesh nodes, vertically structured" ;
Mesh2_edge_velocity_z_3d:units = "m s-1" ;
Mesh2_edge_velocity_z_3d:coordinates = "Mesh2_edge_lon Mesh2_edge_lat" ;
Mesh2_edge_velocity_z_3d:_FillValue = fillvalue ;
Mesh2_edge_velocity_z_3d:valid_range = valid minimum, valid maximum ;
Mesh2_edge_velocity_z_3d:cell_methods = "nMesh2_face: mean" ;
Mesh2_edge_velocity_z_3d:cell_measures = "area: Mesh2_edge_flow_area_3d" ;
Mesh2_edge_velocity_z_3d:grid_mapping = "crs"
double Mesh2_edge_velocity_n_3d(time,nMesh2_face) ;
Mesh2_edge_velocity_n_3d:standard_name = "???" ;
Mesh2_edge_velocity_n_3d:long_name = "normal current velocity for 2D mesh edges, vertically structured" ;
Mesh2_edge_velocity_n_3d:units = "m s-1" ;
Mesh2_edge_velocity_n_3d:coordinates = "Mesh2_edge_lon mesh2_edge_lat" ;
Mesh2_edge_velocity_n_3d:_FillValue = fillvalue ;
Mesh2_edge_velocity_n_3d:valid_range = valid minimum, valid maximum ;
Mesh2_edge_velocity_n_3d:cell_methods = "nMesh2_face: mean" ;
Mesh2_edge_velocity_n_3d:cell_measures = "length: Mesh2_edge_flow_area_3d" ;
Mesh2_edge_velocity_n_3d:grid_mapping = "crs"

Anmerkungen, Fragen

  • Datei ist nicht vollständig CF-konform. Für das Attribut cell_measures müsste length als Wert zugelassen werden

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