To this end, this section features the conversion of the above-created polygon shapefile ( FlowAreas.shp) to a roughness Gridded Cell (Raster) Data. Many numerical models required that roughness is provided in Gridded Cell (Raster) Data format. To improve the visualization, modify the Symbology to Categorized as a function of the AreaType field: Keep Random Colors > Click on Classify > Apply and if you like the visualization, click OK.Ĭonversion: Rasterize (Polygon to Raster) # If you made a drawing error, use either the Attribute Table to select and delete entire polygons, or use the vertex tool from the menu bar.Īfter drawing all polygons, Save edits and Toggle Editing (deactivate).
Start drawing by clicking on the map (right-click finalizes Polygon)ĭraw one polygon of the main channel and after finalizing set:ĭraw two more polygons of the right-bank (RB) and left-bank (LB) floodplains, and set: See more in the following video.Įnable snapping to avoid gaps between the floodplain and main channel polygonsĪctivate the snapping toolbar: View > Toolbars > Snapping ToolbarĮnable snapping from Snapping toolbar > Enable Snapping and Avoid Polygon Overlapping Then draw a line along the Fils River starting 200 m upstream and ending 200 m downstream of the PEGELHAUS by following the river on the OpenStreetMap layer. Add one text field and call it RiverName. Verify the point settings in the Attribute Table (right-click on the gauges layer and select Attribute Table).Ĭreate a Line Shapefile called CenterLine.shp to draw a centerline of the Fils \(\pm\) 200 m around the PEGELHAUS gauge, similar to the above-created point shapefile. Highlight Simple Marker, change to + symbol, and change fill color and size. Improve the visualization by changing the symbology:ĭouble-click on the gauges layer > Symbology Toggle Editing (i.e., enable by clicking on the yellow pen ) > Add Point FeatureĬlick on the PEGELHAUS to draw a point and setįinalize the edits by clicking on Save Layer Edits > Stop (Toggle) Editing by clicking on the yellow pen symbol. In the QGIS top menu go to Layer > Create Layer > New Shapefile Layerĭefine a filename (e.g., gauges.shp - may not be longer than 13 characters), for instance, in a folder called qgis-exercise. To facilitate finding the gauging station in the future, we will now create a point shapefile as explained in the following video and the analogous instructions below the video. From there, follow the Fils River in the upstream direction for a couple of hundred meters and locate the PEGELHAUS (i.e., a gauging station at the Fils River - click to visit). Find the heavily impaired Neckar River in the North of Stuttgart and move in the upstream direction (i.e., Eastern direction), pass the cities of Esslingen and Plochingen until you get to the confluence of the Neckar and the Fils rivers. Zoom on central Europe and roughly locate Stuttgart in Southwest Germany. Start with loading satellite imagery and a street basemap (see above) in the layers pane. To read more about such vector data and other spatially explicit data types, read the section on Geospatial Data. This section guides through the creation of a point, a line, and a polygon Shapefile (vector data). Read more about coordinate systems and projections in the Geospatial Data and shapefile projection sections. To use custom geodata products, make sure that all other layers have the same coordinate system. Most basemaps are provided in the EPSG:3857 -WGS84 / Pseudo Mercator coordinate system (CRS). Save the project as qgis-project.qgz in a new qgis-exercise folder Retrieve point coordinates in any CRS formatĬonvert between different CRSs (e.g., convert 48.745, 9.103 from EPSG 3857 to EPSG 4326) Used by the GPS satellite navigation system and for NATO military geodetic surveying. Scope: Horizontal component of a 3d system. Set the Coordinate Reference System CRS to EPSG:4326: In the top menu go to Project > Properties Once you installed QGIS, launch the program and walk through the following steps to make fundamental settings:Ĭreate a new project ( New Empty Project) To resolve the issue, either open the video links by clicking on the Open Site in New Window button or by changing browser privacy settings (e.g., in Mozilla Firefox). If videos are not displaying, this might be caused by strict privacy settings. If you read: Videos not showing up (Firefox Can’t Open This Page)…
1d Hydraulics (Manning-Strickler Formula).Integrated Development Environments (IDEs).
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