Versions Compared

Old Version 21

changes.mady.by.user Arno Kockx

Saved on

compared with

New Version Current

changes.mady.by.user Klaas-Jan van Heeringen

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.
Comment: Migration of unmigrated content due to installation of a new plugin

example_unstructured_grid_config.zip

scrollbar

...



What
Required
Description
schema location
Grids.xml
no
Grid definitions, either regular or irregular
http
https://
fews
fewsdocs.
wldelft
deltares.nl/schemas/version1.0/grids.xsd
DELFT-FEWS is a location oriented system. All time series data must be referenced to a (geographic) location. Scalar time series need no additional information. For grid time series data, each point in the grid must be referenced to a location in a grid structure.
...
In irregular grids the grid has a fixed number of rows and columns, but the cell height and width is not equal in each row and column. For these grids additional information is required on the location of each individual cell in the grid to allow display in the grids display as well as for use in the spatial interpolation routine.
When available on the file system, the name of the XML file is for example:
Grids 1.00 default.xml
Grids                                          Fixed file name for the Grids configuration
1.00                                            Version number
default                                       Flag to indicate the version is the default configuration (otherwise omitted).
Image Removed
 Figure 28 Elements of the grids configuration
 Table of Contents
regular
Definition of a regular grid. One or more regular grids may be defined.
Attributes;
  •         locationId; location Id of the grid. This locationId must be included in the locations definition.
irregular
Definition of a irregular grid. One or more irregular grids may be defined.
Attributes;
  •         locationId; location Id of the grid. This locationId must be included in the locations definition.
Regular grids
Image Removed
 Figure 29 Elements of the Regular Grid in the Grids configuration
description
Optional description of the grid. Used only for reference purposes
rows, columns
Number of rows and columns in the grid
geoDatum
Coordinate system the grid is defined in. This may be a different coordinate system to that used in the main map display. The coordinate system may also differ per grid, as a grid may be regular in one coordinate system, but may be irregular in another. Defining the grid in the regular coordinate system is easier.
firstCellCenter
Coordinates of the center of the first grid cell. The convention in DELFT-FEWS is that this is the center point of the top left cell in the grid (Upper-Left).
firstCellCenter: x
Geographic coordinate of the first cell center point (Easting)
firstCellCenter: y
Geographic coordinate of the first cell center point (Northing)
firstCellCenter: z
Optional elevation of the first cell center point (Easting). If only this elevation is defined , then all cells in the grid are assumed to have the same elevation.
xCellSize / columnWidth
Cell width of each column in the grid. The cell width is given in the unit of the coordinate system referred to in the geoDatum. Generally this is metres, but in WGS 1984 this is decimal degrees.
For regular grids it is sometimes not required to add the location to the grids.xml when you only want to import/export the grid. Most grid transformations will not work when the output location is missing in the grids.xml. Regular grids that need a custom projection (projectionFile, polarStereoGraphic, geostationarySatelliteView, transverseMercator, mercator, albersEqualArea, azimuthalEquidistant, lambertAzimuthalEqualArea, rotatedCartesian, lambertConformalConic, rotatedSouthPole, rotatedNorthPole, rotatedCartesian, azimuthalEquidistant) should ALWAYS be listed in the grids.xml. The grid geometry should be available in the imported file (netcdf/grib).
When available on the file system, the name of the XML file is for example:
Grids 1.00 default.xml
Grids                                          Fixed file name for the Grids configuration
1.00                                            Version number
default                                       Flag to indicate the version is the default configuration (otherwise omitted).
Image Added
Figure 28 Elements of the grids configuration
 Table of Contents
regular
Definition of a regular grid. One or more regular grids may be defined.
Attributes;
  •         locationId; location Id of the grid. This locationId must be included in the locations definition.
irregular
Definition of a irregular grid. One or more irregular grids may be defined.
Attributes;
  •         locationId; location Id of the grid. This locationId must be included in the locations definition.
Regular grids
Image Added
Figure 29 Elements of the Regular Grid in the Grids configuration
description
Optional description of the grid. Used only for reference purposes
rows, columns
Number of rows and columns in the grid
geoDatum
Coordinate system the grid is defined in. This may be a different coordinate system to that used in the main map display. The coordinate system may also differ per grid, as a grid may be regular in one coordinate system, but may be irregular in another. Defining the grid in the regular coordinate system is easier.
firstCellCenter
Coordinates of the center of the first grid cell. The convention in DELFT-FEWS is that this is the center point of the top left cell in the grid (Upper-Left).
firstCellCenter: x
Geographic coordinate of the first cell center point (Easting)
firstCellCenter: y
Geographic coordinate of the first cell center point (Northing)
firstCellCenter: z
Optional elevation of the first cell center point (Easting). If only this elevation is defined , then all cells in the grid are assumed to have the same elevation.
xCellSize / columnWidth
Cell width of each column in the grid. The cell width is given in the unit of the coordinate system referred to in the geoDatum. Generally this is metres, but in WGS 1984 this is decimal degrees.
The xCellSize-element is The xCellSize-element is used when all cells are equal in width. Please use the columnWidth-element to define cells with variable columnWidth.
...
Optional, when specified the grid cell boundaries can be based on the neighbour neighbor cells. Number of rows and columns in grid, at least two rows and two columns. Don't configure this for scattered point grids.
...
Coordinate system the grid is defined in. This may be a different coordinate system to that used in the main map display. The coordinate system may also differ per grid. A grid may be regular in one coordinate system, but may be irregular in another. Defining the grid in the regular coordinate system is generally easier.
You can also use the EPGS codes
cellCentre
Definition of the cell centre points of all cells in the irregular grid. The number of cellCentre points defined must be the same as the number of cells in the grid (rows x columns).
...
Since 2013.01. Csv file with cell centers. Csv file should contain an "x" and "y" column. The cell centers should be listed from the upper left to the lower right, row by row. For regular grids always try to use a regular grid with a (custom) geodatum. For config example see: 06Grids-ConfigExamples
netcdfFile
Since 2015.02. Reference to a UGRID NetCDF file that contains only grid geometry meta data. This only supports mesh topologies (unstructured grids) with 2D coordinates. This can be 1D network, 2D triangular, 2D flexible or 3D layered mesh topologies. This currently only works for files that are compliant to the UGRID 1.0 conventions. For more information see http://ugrid-conventions.github.io/ugrid-conventions/
...
In an unstructured grid the data can be defined either on the nodes, the edges or the faces of the mesh (staggerLocations). Also see http://ugrid-conventions.github.io/ugrid-conventions/#data-defined-on-unstructured-meshes.
An example configuration can be downloaded here: example_unstructured_grid_config.zip. The example shows what is minimally needed to be present in the UGRID NetCDF file and how one can configure it in FEWS.
Each grid definition in grids.xml is valid for only one staggerLocation and this should match the staggerLocation of the data that you are going to import using the grid definition. The staggerLocation on which the data is defined can be deduced from the data variable in a netcdf file that contains the data to import. The data variable (e.g. "water_level") has an attribute called "location" and a dimension (e.g. nmesh2d_face) that both indicate its staggerLocation. In the grid geometry choose the corresponding staggerLocation. If you want to import different data variables that are defined on different staggerLocations in the same mesh, then you will have to create separate grid definitions for different staggerLocations using the same mesh from the same netcdf file, e.g.:
 Code Block
languagexml
<irregular locationId="SFBayFM_data_on_faces">
    <netcdfFile>
        <file>sfbay_flowgeom.nc</file>
        <geoDatum>UTM10N</geoDatum>
        <meshTopologyVariableName>mesh2d</meshTopologyVariableName>
        <staggerLocation>face</staggerLocation>
    </netcdfFile>
</irregular>
<irregular locationId="SFBayFM_data_on_nodes">
    <netcdfFile>
        <file>sfbay_flowgeom.nc</file>
        <geoDatum>UTM10N</geoDatum>
        <meshTopologyVariableName>mesh2d</meshTopologyVariableName>
        <staggerLocation>node</staggerLocation>
    </netcdfFile>
</irregular>
D-Flow FM (Dutch: D-HYDRO)
It is possible to use a D-Flow flexible mesh (D-Flow FM) flowgeom UGRID NetCDF file, produced by a D-Flow FM model run, as grid definition in Delft-FEWS. If your D-Flow FM model run does not produce a flowgeom file, then add the following line in the D-Flow FM .mdu file in the output section, e.g.:
...
The flowgeom file format will match the configured map file format. If MapFormat is set to 4, then D-Flow FM will produce a valid UGRID file. With MapFormat set to 1 it will produce a format that looks very much like UGRID, but is not the same. Delft-FEWS can only use valid UGRID files. Using MapFormat 1 files with Delft-FEWS may cause problems.
Config Examples
FEWS may cause problems.
If you have set MapFormat = 4, but the flowgeom file produced by D-Flow FM still causes errors in Delft-FEWS, then you may need to update to a newer version of DFlow-FM (1.2.2 or later). Note that in that case, you can manually create a valid flowgeom from the map file by removing all variables that depend on time from the netcdf file. This can be done using the third party command line tool nccopy, using a command like this (with uppercase -V):
nccopy -V mesh2d,wgs84,mesh2d_node_x,mesh2d_node_y,mesh2d_node_z,mesh2d_edge_nodes,mesh2d_edge_x,mesh2d_edge_y,mesh2d_edge_x_bnd,mesh2d_edge_y_bnd,mesh2d_face_nodes,mesh2d_face_x,mesh2d_face_y,mesh2d_face_x_bnd,mesh2d_face_y_bnd,mesh2d_FlowElem_ba,mesh2d_FlowElem_bl,mesh2d_edge_type map.nc flowgeom.nc
The tool nccopy is part of the NetCDF library binary distribution.

Config Examples

 Code Block
languagexml
titlenetCDF file
<irregular locationId="meshLocation">
	<netcdfFile>
		<file>simplebox_hex7_map.nc</file>
		<meshTopologyVariableName>insert_mesh_variable_name_here</meshTopologyVariableName>
		<staggerLocation>face</staggerLocation>
	</netcdfFile>
</irregular>

 Code Block
xml
 Code Block
language
xml
<irregular locationId="meshLocationSwan2D_G2_cellcenters">
	<netcdfFile><rows>1318</rows>
	<columns>317</columns>
	<esriShapeFile>
		<file>simplebox<file>swan2D_hex7G2_mapcellcenters.nc<shp</file>
		<meshTopologyVariableName>insert_mesh_variable_name_here</meshTopologyVariableName><geoDatum>WGS 1984</geoDatum>
		<x>%X%</x>
		<staggerLocation>face<<y>%Y%</staggerLocation>y>
	</netcdfFile>esriShapeFile>
</irregular>


 Code Block
xml
xml
<irregular locationId="Swan2D_G2_cellcenters">
	<rows>1318</rows>
	<columns>317</columns>
	<esriShapeFile>
		<file>swan2D_G2_cellcenters.shp</file>
		<geoDatum>WGS 1984<<projectionFileAvailable>true</geoDatum>projectionFileAvailable>
		<x>%X%</x>
		<y>%Y%</y>
	</esriShapeFile>
</irregular>


 Code Block
titleCSV-file irregularxmlxml
<irregular locationId="Swan2DGrid_G2Waqua_cellcentersZeedelta">
	<rows>1318<    <rows>1539</rows>
	<columns>317<    <columns>501</columns>
	<esriShapeFile>
		<file>swan2D_G2_cellcenters.shp</file>
		<projectionFileAvailable>true</projectionFileAvailable>
		<x>%X%</x>
		<y>%Y%</y>
	</esriShapeFile>
</irregular>
    <csvFile>
        <file>Grid_Waqua_Zeedelta.csv</file>
        <geoDatum>Rijks Driehoekstelsel</geoDatum>
        <x>%X%</x>
        <y>%Y%</y>
    </csvFile>
</irregular> 

 Code Block
xml
xml
<regular locationId="KNMI-HIRLAM-V70">
	<description>grid def. for KNMI-HIRLAM v7.0 with rotated pole</description>
	<rows>226</rows>
	<columns>136</columns>
	<rotatedSouthPole>
		<latitude>-30</latitude>
		<longitude>-15</longitude>
	</rotatedSouthPole>
	<gridCorners>
		<geoDatum>WGS 1984</geoDatum>
		<upperLeft>
			<x>-30.8688</x>
			<y>79.63847</y>
		</upperLeft>
		<lowerRight>
			<x>10.29617</x>
			<y>26.065</y>
		</lowerRight>
	</gridCorners>
</regular>

...
 Code Block
xml
xml
<regular locationId="QPF">
	<description>QPF Grid for ABRFC</description>
	<rows>159</rows>
	<columns>335</columns>
	<polarStereographic>
		<originLatitude>90.0</originLatitude>
		<originLongitude>-105.0</originLongitude>
		<scaleAtOrigin>0.933</scaleAtOrigin>
		<equatorRadius>6367470.0</equatorRadius>
		<poleRadius>6367470.0</poleRadius>
	</polarStereographic>
	<gridCorners>
		<geoDatum>WGS 1984</geoDatum>
		<upperLeft>
			<x>-106.67471389477944</x>
			<y>39.37455858318055</y>
			<z>0.0</z>
		</upperLeft>
		<lowerRight>
			<x>-92.34455929643786</x>
			<y>32.390342856654044</y>
			<z>0.0</z>
		</lowerRight>
	</gridCorners>
</regular>

 

Generating XML
...

For NetCDF and GRIB files you can generate the grids.xml with F12>Clipboard>Copy grib geometry form file