Hi,
I am trying to calculate the Flow Distances for North-American catchments, but the result shows several areas of NoData (there is a picture attached, explanation below). Input is a void-filled DEM and a rivers polyline feature that I converted to a raster, both products are provided by HydroSHEDS and therefore should be linked and suitable for that operation.
The areas of NoData might be associated with a projection issue, since running the tool with the original geographic coordinate system (NAD 1983 (2011)/EPSG 6318) gives an output without gaps. But running the tool with a GCS, the resulting pixel values have unit in degrees!! Preferably the flow distances should be given in meters and for cellsizes of 100*100m.
I ran the tool on one catchment of 104467.82 km^2 to check for several combinations, such as projections and flow models (D8, MFD, DINF), cell sizes, additional input of a flow direction raster (gives even more NoData), which all did not work.
Is there a workaround to get the preferred meters out of the degrees? I am aware of the conversion from dergrees to meters since the calculation needs to be done for the North American continent.
Or, even better, is there a way to calculate the flow distance in a projected coordinate system?
Please find attached a picture of a small extent, 1 pixel = 100m*100m, red lines= rivers, yellow=NoData, in gray the calculated flow distances are displayed
I am using ArcGIS 10.8
Thanks!