Dear Sirs/Madams,
I want to produce an hydrologically corrected raster surface for hydrological modelling (to define flow accumulation, basin limit, stream network, etc.), with the final objective of classifying the stream network according to the flow generated upstream it. The European Environment Agency has the EU-DEM (http://www.eea.europa.eu/data-and-maps/data/eu-dem) with "elevations captured (...) every 30 meters" and described as follows:
"The Digital Elevation Model over Europe from the GMES RDA project (EU-DEM) is a Digital Surface Model (DSM) representing the first surface as illuminated by the sensors. The EU-DEM dataset is a realisation of the Copernicus programme, managed by the European Commission, DG Enterprise and Industry."
I'd like to ask your opinion about this possibility. And what alternatives with a similar resolution are freely available that cover Europe?
Thanks, kind regards,
Pedro
I guess thsi data can be very useful for hydrological modeling and drainage morphometry. There are several alternatives available but certainly you will have to do much more work to gerenate a DEM yourself and will prove expensive.
Another alternative is SRTM at 3 arc second (90m) certainly not better than what you are getting.
Pedro,
The DSM includes the tops of trees, buildings, and other objects. It is not the " bare earth" elevation model. If the densities of these "objects" are higher, the real watershed boundary and stream network may not be correctly identified.
can you find the Lidar point collections to create the Raster DEM?
Good luck !
Yunjie
I wish to encourage you in your work. We need all the information we can get about water flow over the earth's surface. This is especially true in the context of climate change with ever increasing rainfall and increased snowmelt in springtime.
Thank you for your suggestions!
My reluctance on the use of the EU-DEM was precisely because it is a surface model... No, I don't have access to Lidar data for this area. I guess I'll use the DTM freely available from the ESRI site, which has a 30 meter resolution and was made upon ASTER data.
Best regards,
Pedro
is known that low-resolution DEM produce artefacts and reduce the slopes in DEM's.... you can try using Tandem-X topography..., all Europe is covered