Basin_index data

[Safa136]

I wonder where I can download the merit_hydro_index, as I am using merit-hydro for hydrography function and require data for basin-index corresponding to merit hydro data.

[DirkEilander]

The basin index file is basically a vector representation of (the bounding box of) your basins. This file is (only) needed to be able to load only the required area when delineating a subbasin.

I recommend using the IHU upscaled 30 arcsec (~1km) resolution MERIT Hydro which includes a 30sec_basins.gpkg basin index file. You can download this data from Zenodo . Alternatively, you create you're own basin index file by vectorizing a grid with unique IDs per basin obtained using e.g. the pylfwdir.basins method.

Not also this issue #156 to make the index an optional argument.

[Safa136]

Thank you DirkEilander.

[Safa136]

What about era5_orography data? I believe this is the elevation data! but I cant find it to download.

[hboisgon]

The orography data for ERA5 is actually geopotential and because it’s a ERA5 input rather than output, you can download it from the documentation: https://confluence.ecmwf.int/display/CKB/ERA5%3A+data+documentation#ERA5:datadocumentation-Table1
In that table, it is line 9 geopotential.

[Safa136]

Thank you very much Hboisgon.

[Safa136]

Please help with this error:

build - main - ERROR - Geotransform and/or shape do not match.
xarray.core.merge.MergeError: Geotransform and/or shape do not match

[hboisgon]

Hi @Safa136 how did you preapre your merit_hydro/{variable}.tif file? Note that for hydromt to consider a dataset has the same data source (data catalog entry), all variables must have exactly the same grid definition (CRS, resolution, x, y coordinates). If you merge several tif files together (for example in QGIS), you may easily make mistake and get merged tif variables in slightly different grid. This is why we recommend to use the vrt format espeically for Merit Hydro. You can learn more here how to produce a vrt file based on several tifs: https://deltares.github.io/hydromt/latest/user_guide/data_types.html#multi-variable-virtual-raster-tileset-vrt

[hboisgon]

By the way, input data related issues are reported in issue #157. I'll now close this one to have one single issue on the topic. If you find something else related to input data, please post there and for new issue, just open a new one!