A Carthography of Receding Glaciers on Svalbard | The Use of Open Source Geo-Data & GIS Software | Tooling Workshop
Area of Investigation: Kronebreen & Kongsvegen on Spitzbergen | Size of Terrain: 20 x 20 km | Source of Data: The Norwegian Polar Institute, Kartverket, Geonorge | Software: QGIS
PART I
Workshop 16/17 September
| Workshop Database: | https://we.tl/t-c7f2UM66uf |
| Workshop Software Package: | https://we.tl/t-udAUTyRg1t |
>>> you will also find most of the relevant links also on: https://digital-landscapes.com/raw-studio/ The Site will be updated during the Workshop | To unzip files you can use: 7-zip (free software installer)
QGIS
01 | Set the CRS to EPSG: 25833 – ETRS89 / UTM zone 33N
Project>Properties>CRS and also under: Settings>Options>CRS>Use a default CRS
02 | Link Ortho Image via WMS/WMTS
WMS-Layer in QGIS: LINK_Ortofoto_Svalbard_WMTS_25833
add more WMS Layers (Geology / Biology / Glaciology)
Extract Transformation/Changes over Time | Compare orhto- and satellite-image > change Blending Mode to difference > see the movement of the ice | https://www.unis.no/dynamics-svalbard-glaciers/
what layes underneeth the ice surface?
03 | Download and Reference Digital Terrain Model (DTM)
For a high resolution Terrain Model of the Area of Kronebreen and Kongsvegen download below the GeoTiff # 13822 | Also you will find at the Norwegian Polar Data Center DTM’s in 20m and 50m Grids
| DTM 5m Grid | Delmodell 5m 2009_13822_33 (GeoTIFF) |
| DTM 20m Grid | Terrengmodell Svalbard 20m (GeoTIFF) |
| DTM 50m Grid | Terrengmodell Svalbard 50m (GeoTIFF) |
Unzip Folder >>> QGIS >>> add Raster Layer > Browse to Database > select .TIFF file
04 | Adjust Symbology & Transparency
Change Style Settings: Custom Ramps, Colour, Blending Mode, Transparency …
Add High Resolution DTM 5m – 13822
add Raster and Change style settings e.g.: to Hillhade, or to ‘Singleband Pseudocolor’ Layermanagement
05 | Clipping Raster Data
Extract 10 x 10 km area of the DTM5m > go to: Raster > Extraction > Clip Raster by Extend |
07 | Extract Layer Extend
Extract Extend of the Raster as SHP Layer | rename layers | save to FGDB (FileGeoDataBase) | adjust style settings
08 | Extract Contours
Extract Contour Lines at an Custom Intervall
09 | Raster Calculator
using simple Expressions … like Masking: (“elevation@1” >= 0) * “elevation@1”; Culling: (“elevation@1” < 300) * 1 + (“elevation@1” >= 300) * 200
https://docs.qgis.org/2.8/en/docs/user_manual/working_with_raster/raster_calculator.html
"elevation@1" > 200 AND "elevation@1" > 300 | e.g.: all Points with an elevation of 200 and 300 m
10 | Adjust Layersettings, Color Ramp
Style Settings
11| Basic Terrain Analysis – Using SAGA GIS
Basic Terrain Attributes: Slope, Aspect, Water Flow, Topographic Wetness, Curvature
12 | Calculation of More Grid Data
More Terrain Attributes: Solar Analysis / Topographic Openness / Wind Exposure
13| Saving Raster and Vector to Database
Export ESRI-Grid / ASCII / XYZ / GeoTIFF / JPG / PNG / SHP / DXF
14 | Adding Vector Data to QGIS
15 | Graphic Composition
Layering Information
16 | Export Maps
Using the Print Composer / Layout Manager
