#BEST RASTER FORMAT FOR QGIS HOW TO#
#BEST RASTER FORMAT FOR QGIS PLUS#
#BEST RASTER FORMAT FOR QGIS ZIP#
#BEST RASTER FORMAT FOR QGIS DOWNLOAD#

Browse to your exercise folder and name the output file dem_reprojected.tif.Set the Output file resolution to 30 m.In this way we define that 'no data' has a value -9999 and will not be visualised and treated as 'data'. Set the No data value for output bands to -9999 because when the raster layer is reprojected there will be 'no data' at the borders.For the Resampling method we choose Nearest Neighbor to preserve the elevation values of the original files.In the dialogue that opens type 32632 at Filter and select WGS EPSG: 32632 in the middle of the dialogue window and click OK. In the Warp (reproject) window, click to choose the Target CRS.Ĥ. From the main menu choose Raster | Projections | Warp (Reproject).ģ. Now we are going to reproject the DEM from unprojected GCS (Lat/Lon WGS 84 - EPSG: 4326) to UTM Zone 32 North / WGS 84 (EPSG: 32632).Ģ. We will use EPSG: 32632 throughout this project - clicking on it will provide more details. We need to take a look at the EPSG codes. You can leave QGIS running and open a browser. Use the website to search for UTM 32N wgs 84. Therefore we will use a global projection: UTM Zone 32 North, with WGS-84 as datum.ġ. In our case, however, the project covers multiple countries (Germany, the Netherlands, and Belgium). If the project covers one country we can choose a national projection. We need to choose a projection for our project. meters) are different than the x and y units (degrees). It is not recommended to use a GCS for DEM analysis, because the z units (e.g. The DEM is in its original Lat/Lon Geographic Coordinate System (GCS) with datum WGS 84 (EPSG: 4326). Right-click on one of the tiles and choose Properties to review the metadata. In the Browser panel add the folder with the data for this chapter to the Favorites.ġ1. The tiles can now be added to your QGIS project.ġ0.

#BEST RASTER FORMAT FOR QGIS DOWNLOAD#

In the Download Options dialogue download the DEM in GeoTIFF Format to the exercise folder on your hard disk. Download each tile by clicking the Download Options button.Ĩ. With the foot icon, for example, you can see the footprint of the tile.ħ. Before downloading you can check the tiles. Now you see the search results: four tiles.

#BEST RASTER FORMAT FOR QGIS PLUS#

Click on the plus signs to select Digital Elevation | SRTM | SRTM 1-Arc Second Global. Choose Data Sets to go to the next screen where we can select the data set.ĥ.

#BEST RASTER FORMAT FOR QGIS ZIP#

Choose Shapefile and upload the boundingbox.zip file (you need to first zip all files belonging to the boundingbox shapefile!).Ĥ. For this case we prepared a shapefile with a bounding box.ģ. In EarthExplorer this can be done in different ways: (1) Search for a location name, (2) Zoom in on the map and use the coordinates of the zoom area, (3) Upload a KML or zipped shapefile. After registration, log in to the USGS EarthExplorer portal. If you don't succeed with making an account you can use the SRTM tiles provided with the data of this lesson (4 GeoTiff files).Ģ. In order to download the SRTM DEM tiles you need to create an account.

#BEST RASTER FORMAT FOR QGIS HOW TO#

The following steps explain how to download the SRTM DEM tiles for the study area. A description of the SRTM data products can be found here. Most parts of the world have been covered by this dataset ranging from 54 degrees south to 60 degrees north latitude. Since the end of 2014 a 1-arc second global digital elevation model (approximately 30 meters at the equator) has been released as open data. This is beyond the scope of this chapter.įor the Rur study area, we will download the tiles from the SRTM 1 Arc-Second global data set. In that way the DEM is always lower at rivers and runoff will follow the actual river network. When a map with the stream network already exists, the procedure can be improved by 'burning' the river network into the DEM. Calculate the catchment for the outflow point of the catchment. Calculate the flow direction for each cell.ĩ. Make a hydrologically correct DEM by filling sinks and removing spikes.ħ. Interpolate voids when pixels with no data exist in the DEM.Ħ. In the case that the merged tiles are much larger than your study area, you can subset (clip) it to a smaller area to reduce calculation time.ĥ.

In that case you have to reproject the DEM layer to the projection you want to use in the study area.Ĥ. The DEM tiles might be in a different coordinate system then desired. If your study area is covered by multiple DEM tiles, you need to mosaic (merge) the tiles to create a single raster DEM layer.ģ. Better to take it a bit larger to avoid boundary effects.Ģ. Make sure that the tiles cover at least the study area and that the catchment you want to derive is covered completely. Download the DEM tiles of your study area. In order to delineate a catchment from a DEM in GIS we need to follow these steps (details covered in this lesson):ġ.

Best raster format for qgis