King Fire Burn Area

Christopher Scott

w1759113apps.losrios.edu

American River College, Geography 350: Data Acquisition in GIS, Fall 2020

Abstract

The King Fire started September 13, 2014 and burned almost 100,000 arces of forest. The cause of the fire was arson. It was set at the bottom of Forebay Rd on King of the Mountain Rd. in Pollock Pines, California. Due to the dry conditions and the bark beetle infestation the fire spread very quickly and became the 2nd largest fire in California at that time. My intention was to create maps that can show the health of the burn area by running Band Arithmetic on satellite images.

Introduction

The purpose of this project is to show how satellite imagery can be manipulated in ArcGis Pro to display and transform color bands to make vegetation features stand out for analysis of forest growth. I chose this subject because I live very close to the area this affected. The images will show the burn area before, during and after the fire. For reference I’ve included a map of the fire perimeter represented by the polygon shown below.

Background

The fire burned northeast up the American River Canyon and at one point came up to Highway 50 in Pollock Pines which caused evacuations. 5 days after the fire was started a man was arrested on suspicion of starting the fire. Selfie video of him starting the fire was found on a cell phone. 2 years later he pleaded guilty to the charges and went to jail. The fire was contained by October 10, 2014. The rains came and he weather helped firefighters get it under control. King Fire

Methods

I obtained 7 Band Landsat8 imagery in Geotiff format for the burn area from Earth Explorer. The imagery is from 8/18/2014, 9/19/2014, 10/21/2014 and 9/17/2019. The images below represent those dates from left to right.

To achieve the image transformation I first added the images to the folder connection and added them to the Geodatabase. The images were added as a feature layers processed through Band Arithmetic using the Ratio Vegetation Index of B5/B4. The Colorized NDVI tool was used to normalize the different reflective materials.

The symbology of the color bands were changed to:

Red Color Display – Band 5

Green Color Display – Band 6

Blue Color Display – Band 4

Although counter intuitive it changes the image to show vegetation as not healthy or dead (green) and healthy (orange). The smoke or snow came out with a purple tint. The blue/gray is usually rock outcroppings. In each of the images shown above you can see the progression of the damage done by the fire and the new growth after the fire.

Results

Changing the color bands gave the desired transformation to show both healthy, the burned and some regrowth of the forest. 2 years of above average rain along with logging and replanting is helping with bring the forest back.

Analysis

What we can see in the imagery after the band transformations is that one month before the fire the forest look fairly healthy. There are spots of damage indicated by the green shading that show stress from drought and bark beetle damage. During and immediately after the fire the dark green clearly shows the burned scar area. 4 years later we can see that the abundance of precipitation and some reforestation the burned area is coming back to life, indicated by the lighter green shading.

Conclusion

The band transformations run on these images presented a high level overview of the health of the King Fire burn scar. After processing I realized that I could have went a step further and run the imagery through a supervised classification to break down the different kinds of plants, grasses and trees. Processing these images in this manner can be is a helpful tool for all those involved to properly manage the forest growth and conditions.

References/Citations

Satelite Images: Earth Explorer, https://earthexplorer.usgs.gov/

Fire Perimeter Layers: Forest Service, https://data.fs.usda.gov/geodata

General Fire Information: Wildfire Today, https://wildfiretoday.com/2014/09/14/california-king-fire-near-pollock-pines/