H2Flo data format and strucure

Here we describe the structure of a H2Flo project and the structure of its files.

metadata.json

A JSON file containing the metadata of a H2Flo project. The content of keys are explained in the JSON-schema file metadata-schema.json.

Grids

The grids-folder contains the following files with a structure as explained: link_coordinates.dia: A space-seperated-value ASCI file with the following columns:

1. id: int, unique index for the link – ordinal (1-based)
2. direction: int, direction of flow; 0 = horizontal, 1 = vertical
3. node_from: int, id of the links first node
4. node_to: int, id of the links last node
5. x_from: x-coordinate of the links first node
6. y_from: y-coordinate of the links first node
7. x_to: x-coordinate of the links last node
8. y_to: y-coordinate of the links last node
9. zmin: float, minimum level at the velocity-face
10. zmax: float, maximum level at the velocity-face

node_coordinates.dia: A space-seperated-value ASCI file with the following columns:

1. id: int, unique index for the node – ordinal (1-based)
2. x: float, x-coordinate of the node
3. y: float, y-coordinate of the node
4. ridge: int, indicates if it is a node adjacent to a ridge; 0 = no-ridge, 1 = ridge
5. dxy: float, size in x and y direction of the node-cell (quadtree cell size in meters
6. zmin: float, minimum level in the node-cell
7. zmax: float, maximum level at the node-cell

node_dem.dia An ESRI ASCII file (https://desktop.arcgis.com/en/arcmap/10.3/manage-data/raster-and-images/esri-ascii-raster-format.htm) on the resolution of, and alligned with the DEM-raster. Every cell contains the topology node-number the DEM-cell is mapped to.

grid.gpkg A GeoPackage (https://www.geopackage.org/) containing a postprocessed grid into four layers:

1. link_coordinates: the information of link_coordinates.dia in attributes including the link as LineString geometry
2. node_coordinates: the information of node_coordinates.dia in attributes including the node as Point geometry
3. node_mask: the information of node_coordinates.dia in attributes including the shaped-version of node_dem.dia as Polygon goemetry
4. node_mesh: the information of node_coordinates.dia in attributes but as the most accurate possible representation of the mesh-topology. This layer will differ from node_mask at ridges as it will here be represented by straight lines.

Flows/ts

The flows/ts-folder contains the results of a H2Flo run: timesteps.asc: A space-seperated-value ASCI file with the following columns:

1. id: int, identification of the timestep (ordinal, 0-based)
2. Cumulative-time: float, cumulative time (seconds) since start simulation

Multiple Fortran Unformatted Binary Files that can be read by fortio https://pypi.org/project/fortio/. Every record contains all values for all nodes or links in the topology. A list of result-files:

• discharges2d.dat: discharge (m3/s) over links
• velocities2d.dat: velocities (m/s) over links
• thinwaterdepths2d.dat thin water depth (m) at nodes
• volumes2d.dat volumes (m3) at nodes
• waterlevels2d.dat water levels (m + datum) at nodes
• velocityupwind2d.dat upwind velocity (m3/s) ánd direction (radians) at nodes (vector data)
• speedmax2d.dat max velocity of all subgridcells @ nodes.

In velocityupwind2d.dat all uneven records (first, third, fifth, ...) contain velocity magnitue. All even records (second, fourth, sixth, ..) contain direction in radians. Direction is represented by floats ranging from -Pi to Pi, where:

• 0 = East
• Pi = West
• 0.5Pi = South
• -0.5Pi = North