1. Three Year Drought Analysis A Tasseled Cap Transformation Folsom Lake, CA Joseph Watkins GEOG 342 Final Project

2.  Perform a Tasseled Cap Transformation on the Sacramento River and American river independently, over a three year period to determine if the current drought had an equitable impact. Initial Idea – Two Rivers Analysis

3.  www.earthexplorer.usgs.gov was used to find Landsat-8 imagery of Sacramento county.  Image parameters consisted of:  Place: Sacramento, CA.  Date: July 20 th – July 31 st 2013, 2014, and 2015.  Data Set: Landsat-8 OLI (Operational Land Imager) and TIRS (Thermal Infrared Sensor).  Additional Criteria: Cloud Cover less than 20%, and Day indicator.  This resulted in 7.5 gigabytes of imagery. Initial Idea – Two Rivers Analysis

5. Footprint too small!

6.  SJWD water source as stated by www.SJWD.org: “Your water flows straight from the pristine American River watershed to Folsom Lake. “ www.SJWD.org New Project Overview – Drought Impact on Folsom Lake and water use in the San Juan Water District

7.  File archiver needed to extract.tar.gz files to view USGS Landsat-8 images. Specs – 7-Zip

8.  Search for Landsat-8 TC coefficients.  Forum used from gis.stackexchange.com and confirmed through ESRI. Specs – Acquire TC coefficients

9.  Path, Reference, Bands, and Coefficients. Specs – Tasseled Cap Script Mod

10.  Perform a heads-up digitization of Folsom Lake using the Draw tool to create a manageable subset image.  Import additional images and repeat subset process. Method – Folsom Lake Subset 201320142015

11.  Determine the SJWD boundary.  Create a subset image of SJWD sample area using the same method as Folsom Lake.  Import additional images and repeat subset process. Method – SJWD Subset

12.  The Tasseled Cap program revealed image Brightness, Greenness, and Wetness for each image. Transformation

13.  Reference each image Histogram to derive the mean figures. Transformation

14.  Excel charts were created to compare SJWD water use to the receding water line of Folsom Lake. Analysis

16.  IT WORKS!  Effectively tells a story about the image  Easy to use  Runs in under a minute  Handles large amounts of data  Engages the analyst in creative potential Conclusion

17.  Folsom Lake footprint saw a 48% reduction of wetness over the 3 year analysis.  SJWD sampling saw a 16% reduction in wetness.  More factors would need to taken into account.  Consumption of other water districts.  Water release for farming & salmon spawning.  Authorized watering day vs. image date.  Conservation efforts are working. Conclusion