GIS Workflows

The flow of information through a project.

GIS Research Process

  1. Define your research question
    • Identify the problems you will address and determine scale of your analysis
    • Explore the available data
      • Adjust your research question as needed
    • Outline a plan for your analysis
  2. Conduct your analysis
    • Clean, convert, reproject, and reclassify input data
    • Spatial overlays, statistical tests, summary statistics, etc.
    • Refine and incorporate more data as needed
  3. Share your results
    • Visualizations, reports, publications, press releases, etc.
    • Identify new questions
      • Good research often generates more questions than it answers

Visualizing a Workflow

It is a good idea to think through a workflow before conducting it.

  • A flowchart is a diagram that outlines the key steps in an analysis
  • A flowchart can help you
    • Identify necessary analysis steps
    • Think through the logical progression of analysis steps
    • Catch errors before you start working
    • Share your planned analysis with colleagues, funding organizations, etc.

TopHat Question 1

A _______ is a diagram that outlines the key steps in an analysis.

An Applied Example

Port Alberni has needs a new tsunami evacuation shelter and you have been tasked with finding a suitable location. The shelter must:

  1. Outside the flood zone:
    • > 15 MASL or > 1 km from coast.
  2. > 1.5 km from existing shelters.
  3. < 250 m from an Arterial Roadway.
  4. Not on Residential, Commercial, or Industrial parcels.

Visualizing a Workflow

It is best to create a workflow that is repeatable, modifiable, and sharable.

  • "Point and Click" GIS is not repeatable
  • This can create issues when you:
    • Need to write up a report
    • Want to share how you completed a task
    • Have to redo or update complex analyses

Visualizing a Workflow

Model Builder is a good solution for beginners.

  • It lets you define you analysis steps using a flowchart
    • Inputs are run trough the geoprocessing steps
    • Models are easy to save and update
    • Can be exported as custom tools
  • Helps you visualize your results and share them with others

TopHat Question 2

This is useful tool in ArcGIS Pro that lets you define your analysis steps using a flowchart and create repeatable workflows.

  • Model Builder
  • Geoprocessing
  • Raster Calculator
  • Google Earth Engine
  • Python

Visualizing a Workflow

If you pursue a GIS career, or any other science, you should consider learning to code.

  • Code is replicable, legible, and even more explicit than a model
  • Python is a great option for geospatial analysis
  • Javascript is great for making web based applications and interactive visualizations
  • R is useful for statistical analysis

Models can be exported as Python code!

Javascript can create interactive web maps!


Javascript can create interactive web maps!

TopHat Question 3

These are programming languages that can be used to for GIS:

  • Python
  • Microsoft Excel
  • Javascript
  • ArcGIS Pro
  • R