AAG CyberGIS Workshop

(Snow cover frequency linear fit trend between 2004 and 2014 (Blue: Increasing trend; Brown: Decreasing trend))


Welcome to the tutorial for AAG 2015 Annual meeting "CyberGIS Education Workshop".  In this tutorial, we will cover how to use the Google Earth Engine JavaScript application program interface (API) to:

  • Join and modify MODIS datasets
  • Calculate snow cover frequency for a given time period
  • Use reducers to generate a linear fit trend
  • Visualize and export maps for display in Google Earth and Google Maps.
  • At the end of this tutorial, you will hopefully have gained a clearer understanding of the power and potential that Google Earth Engine (GEE) offers, and you will have created the map above that you can share with others.

    Audience:
    This tutorial is geared especially towards the AAG 2015 Annual meeting "CyberGIS Education Workshop".  Unfortunately, we only have 45 minutes to introduce you to the platform and it's potential, so this tutorial will move fast.  We will cover some of the more basic Google Earth Engine operations, and assume only a low level of programming knowledge.   After the meeting, you may want to start with a video presentation on the platform given by David Thau, a senior designer at Google.  Other valuable beginner information includes a brief tour of the platform and the API introduction tutorials, but we will endeavor to explain each step as thoroughly as possible.

        Table of Contents:
         1. What is Google Earth Engine
         2. Outline and Goals
         3. GEE Data Types and Operations
         4. Creating ImageCollections 
         5. Joining Collections
         6. .map() and .mask()
         7. Reclassify
         8. Calculating Snow Cover Frequency
         9. Trend Analysis
       10. Visualization
       11. Disseminating the Trend Analysis Map
       12. References

    Next ->