1. INVESTIGATING THE USE OF
GIS SOFTWARE FOR WEATHER
FORECASTING APPLICATIONS
COMPLETED FOR SCOTIA WEATHER
SERVICE INCORPORATED

2. Enough about me, let’s talk about Q’
• Background
• Goals
• Software used
• Methods
• Outputs
• Analysis

3. Acknowledgements
• David Coleville (Supervisor)
• Mark Hebert
• Trevor Milne

4. BACKGROUND

5. Scotia Weather Services Incorporated
• Based out of Dartmouth
• Provides weather forecasting and environmental
consultation services to a wide variety of clients.

6. Scotia Weather Services Incorporated
• Currently provides Scotia Power with Wind Data.
• Investigating the possibility of using GIS software to
measure to potential effect of weather events on the
power grid.

7. GOALS

8. Goals
• To use scripting in QGIS in order to process data on
forecast wind speed, in such a way as to represent
variations across local regions and their potential effect on
the power grid network.
• Create a parallel set of scripts and models in the ArcGIS
environment in order to compare the functionality of the
QGIS and ArcGIS software packages.

9. SOFTWARE USED

10. QGIS
• The world’s leading open source GIS
• User-friendly interface
• Free!
• Comes with additional open source geospatial software
• GDAL
• SAGA
• Grass
• Currently on version 2.20 (Valmiera)

11. PyQGIS
• Python extension for geoprocessing
• Present in the program since version 0.9
• Can be used in the Python Console
• Interface features an in-program editor

12. PyQGIS

13. ArcGIS
• Industry standard
• Features its own scripting extension ArcPy

14. METHODS

15. Data provided by SWSI
• 48 rasters
• 1 shapefile for Transmission lines from Scotia Power

16. Data Prep

17. Raw Data (Forecast 30)

18. Exclude Zero values
• Null values set as -9.99e+008
• Values under 0 removed using a Con/IfElse statement

20. Recalculating values
• Values only represent surface wind speed
• Needed to recalculate values for
• Wind gust speeds
• Elevation at pylon height (50m)

21. Pylon Wind Gust

22. Excluding Values Under Thresholds
• 60 km/h for sustained wind speeds
• 90 km/h for wind gust speeds

24. Convert Raster to Polygon

25. Clip Affected Transmission Lines

26. OUTPUTS

27. Outputs in PyQGIS vs. ArcPy
• PyQGIS:
• Graphical
• Project Files
• Arcpy
• Graphical
• CSVs

28. Sample Ouput

29. Pylon Wind Forecast AVI for Region 5

30. ANALYSIS

31. Comparing scripts
• PyQGIS
• Five scripts
Two for extent creation
Data processing
Graphic creation
Project creation
• ArcPy
• One Script
• Produced graphics
• CSVS

32. Advantages the Environments
• QGIS
• Free!
• Comes GDAL, SAGA
Grass
• ArcGIS
• Stable
• Well Documented
• Well Supported

33. http://pyqgis.blogspot.ca/

34. Issues with QGIS
• Lack of documentation
• Unstable
• Problems with running scripts multiple times
• User interface malfunctioning

35. Conclusion
• Scripting is definitely a good option for processing
weather forecast data
• PyQGIS dos not match the user friendliness of the QGIS
user interface

36. QUESTIONS?