First steps in ArcGIS

1. 70°N. 60°N. 50°N. First steps in ArcGIS [andArcInfo] by Achilleas Psomas &Niklaus E. Zimmermann,WSL, Birmensdorf

2. What we will cover in this intro-course • What is ArcGIS (ArcInfo)? • Import and Export of data (mostly points) • Display of geographical objects • Simple overlay functions (points  grid) • Analysis and simulation of raster data • Converting data • Writing simple AML codes

3. Printing Digitising Scanning Storage Handheld Network What we will cover in this intro-course Processing Output Input GIS Software Table after Burrough et al. 1998

4. What is a GIS? ctnd. Software used in this introduction • ArcGIS • ArcMap • ArcCatalog • ArcToolbox • HTOOLS-Extension • ArcInfo • Arc • GRID • Tables

5. What is a GIS? ctnd. Terminology in ArcInfo / ArcGIS ArcInfo ArcView ArcArcGIS pointcoverage shapefile shapefile Points ArcSDE linecoverage shapefile shapefile Line ArcSDE polygoncoverage shapefile shapefile Polygon ArcSDE Grid grid grid grid ArcSDE

6. Overview of ArcGIS Programs ArcMap: Display, Layout, Analyses (from extensions)

7. Overview of ArcGIS Programs ArcCatalog: Archive, Database, Some I/O operations

8. Overview of ArcGIS Programs ArcToolbox: Conversion, Analyses, Operations, Statistics

9. The most important ArcINFO Programs Arc [basic operations] ArcEdit [editing, digitizing, cleaning] ArcPlot [visualizing, map generation] INFO [Thematic data: I/O, statistics] Grid [Raster Analyses & Mapping] Tables [Thematic data: I/O, statistics]

10. The most important ArcINFO Programs

11. Importing Points into ArcGIS From Excel • Mark Data Space and Save as dBaseIV File • TOOLBOX: Import to Coverage – Table to Point Coverage • Mark dBase Option, Open File • Set Y and Y columnm and import From AscII File • TOOLBOX: Import to Coverage – Table to Point Coverage • Mark Textfile Option, Open File, Set item labels (columns) • Show File helps to „see“ the data • Select X and Y column and import

12. Convert Points to Shapefile In ArcCatalog • Right-click on point coverage and • select Export – Coverage to Shapefile In ArcToolbox • Export – Coverage to Shapefile • Select File and Export

13. Visualize Points First View in ArcGIS • Open ArcGIS • Click on the Add Data button • Or: File – Add Data • Or: Drag File from ArcCatalog to the Layers Area in ArcMap • Double Click (=Properties) on Shapefile Name (not symbol). • Get through menu, select other symbol / color (e.g. large) • Add a same file a second time but select only C.alba • Properties – Query Builder  „C_alba“ = 1 • Select Symbol • Labels – Enable Labels – Label Field  select ID

14. Switch from Data View to Layout View Make it a complete Map Add all required map features Data • Adjust Page setup Layout • Add the following map items: • Title • Legend • North Arrow • Scale Bar

15. Make it a complete Map

16. Add more layers to the map • Lets add an elevation map [ArcMap] • Add layer – dtm2_int [do NOT build pyramids] • Right-Click – Select Properties – Symbology • Zoom out to full raster [blue-green globe button] • Move elevation raster below points • Add dtm_shd as above, but do not change colors • Move it below other layers • dtm2_int 30% transparent [Properties – Display]

17. Save a map, and export it to a file Saving a map • You can save a map layout or simply a map composition (data view) so that you can continue the next time where you were: • ArcMap: File – Save as – Path\Name • If you want to export a map into a presentation, you can do so as follows: • ArcMap: Export Map – File name/File Type

18. Mutiple layers on a layout You may want more than one map on one page • Go to the layout view • ArcMap: Insert – Data Frame [give name] • Position the new Frame on the page • Add new layers so that you now have maps filled in. Add all necessary map information.

19. Start generating your own layers • Create a topographicillumination • ArcMap: Spatial Analyst – Surface Analysis – Hillshade • Create a slopeand an aspectmap • ArcMap: Spatial Analyst – Surface Analysis – Slope / Aspect • Create 20m contourlines • ArcMap: Spatial Analyst – Surface Analysis – Contour • Display all generatedmaps

20. Calculate the crown (object) heights • Add dsm_int[The heightofobjects not oftheground] • Calculatethedifferencebetweendsmanddtm • ArcMapArcToolboxSpatial AnalystMap Algebra – Raster Calculator

21. Display the crown (object) heights • Hillshade the dsm_int map • Select yellow-red-pink-blue gradient as colors for veg_height • Select „Stretched“ not „Classified“ in the Properties – Symbology of veg_height • Make veg_height 50% transparent, and locate above dsm_shd

22. focal zonal Summary of raster-based analyses Three basic raster analyses types exist • Global Operations • Focal Operations • Zonal Operations So far we have only used global operations global

23. Global raster operations Raster Calculations • Youmaywanttogenerate a temperaturemapstartingfrom a simple formula: • Tjune = 20.43 – (0.0058 * Elevation) • ArcMapArcToolboxSpatial AnalystMap Algebra – Raster Calculator • Tjune = 20.43 – (0.0058 * dtm10_int) • The rastercalculatorallowsyoutoapply an operationglobally, i.e. toeachpixelofthewholemap.

24. Neighbourhood analyses FOCAL analyses • FOCAL analyses allow us to derive statistics within a moving (neighborhood) window • The result of the analysis per window position is written to the center cell in the output grid

25. Neighbourhood analyses FOCAL operations include[not exhausive] • FOCALMAX = 30 • FOCALMEAN = 12.2 • FOCALMEDIAN = 10 • FOCALMIN = 0 • FOCALRANGE = 30 • FOCALSTD = 9.4 • FOCALSUM = 110 • FOCALVARIETY = 5 • FOCALMAJORITY = 10 • Such analyses can be used for MANY different tasks: Smoothing, Topographic Analyses, etc. etc.

26. Neighbourhoodanalyses Topographic Analysis • 3x3 neigbourhoodelev. mean

27. Neighbourhoodanalyses Topographic Analysis • Let‘scalculatethedifferencebetweentheelevationofeachpixelanditsneighbourhoodmean ArcMapArcToolbox: Spatial Analyst – Neigborhood – USE: dtm10_int Set heightlayer, Field = VALUE, Type = Mean, Neighbourhood = CIRCLE, Units = Cell, Radius = 5, Output  give Drive:\Path\Name  ArcMapArcToolbox: Spatial AnalystMap Algebra – Raster Calculator topo_diff = dtm10_int – FOCALMEAN(dtm10_int,CIRCLE,5,DATA)  GRID: topo_diff = dtm10_int – FOCALMEAN(dtm10_int,CIRCLE,5,DATA)

28. dtm10_int topo_diff = dtm10_int – FOCALMEAN(dtm10_int,CIRCLE,5,DATA) Neighbourhood analyses Topographic Analysis

29. Zonal Analyses Zonal Analyses • Similar to focal, the zonal analyses allow us to calculate statistics of areas smaller than the total grid • Each summary statistics is calculated across all pixels belonging to the same zone (= integer value). Thus, the zone-grid must be of integer data type.

30. Zonal Analyses • Let‘scalculatethemeanvegetationheight per foresthabitat type (plant communitiesaccordingtoEllenberg-Klötzli [1972]). • ArcMapArcToolbox: Spatial Analyst – Zonal Statistics • Usethe EK72 gridaszonegrid, output „mean“

31. Reclassify Grids • Wewanttoreclassifythevegetationheightinto 4 classes: +/-0:10; 10-20; 20-30; >30m • ArcMapArcToolbox: Spatial Analyst – Reclass-Reclassify

32. Change Cell Size in Output Grids • Wewanttogenerate a 20m dtmof integer type, thusweusetherastercalculator: • ArcMap: Geoprocessing-Enviroments • First wesetthe Raster Analysis – Cellsize, so thatcellsize = 20m; set also outputdirectory (from Workspace)! • Next we open the Raster Calculator • We type thecommand: dtm20_int = int(dtm2_int) • DON‘T FORGET tosetoptions back!!! • Hillshadethe dtm20_int grid.

33. Fewimportantoperationstopractice Explorethefollowingoperations: • Generate a mapofvegetationunit #8 • Calculatethesquareofvegetationheight • Calculatethe median vegetationheight in a 8-cell circularneighbourhood • Howmanypixelsare in mapunit #8 forelevations ranging from 600-700 m?