Hello, I have a large rectangular domain (topography) in NetCDF file and I am supposed to create a basin mask for further rainfall processing inside the domain. I have defined the basin borders I will use, but don't know what to do next. I have to assign the value -9999 to every pixel outside my basins , so the model simulator I will use later won't operate on unnecessary land.
The file attached shows the screenshot of my domain and needed basins to give you an idea. As a note: my basin borders are currently imported from CAD file as Polygons.
I will be faithful if someone can offer some step-by-step process that I'm supposed to do.