Calculating land use change in west linn from 2000-2017 Corrigan Etheredge GEOG 580 Remote Sensing 12/3/2017

Population change Like much of Oregon, the Portland suburb West Linn has experienced an increase in population 2000* Population: 22,261 Housing units: 8,687 2010* Population: 25,109 Housing units: 10,035 With an increase in population comes an increase in housing, roads, businesses, etc. *Statistics from the Oregon 2010 Census https://www.census.gov/prod/cen2010/cph-2-39.pdf

Research question How much has land use change has occurred in West Linn, Oregon since 2000?

methods Calculate land use area in square feet using Landsat remotely sensed data with a focus on urban features Use false color (urban) band combinations to highlight urban areas Train image classification to 4 land use types: Urban: Buildings, roads, asphalt lots, and other man made structures Developed: altered land for future development, property lots, bare earth, and agriculture Green space: forests, parks, and other vegetated areas Water Run maximum likelihood classification Convert raster to polygon Clip polygon by West Linn city boundary Dissolve polygons by land use type Add new field (long integer) and calculate geometry by square meters.

Data Data projected in WGS 1984 UTM Zone 10N 2017: 2000: Study Area: Landsat 8 image captured August 15, 2017 Multispectral raster file used LC08_L1TP_046029_20170815_20170825_01_T1_MTL ArcMap basemap used for reference 2000: Landsat 7 image captured August 8, 2000 Composite band tool used for bands 1-7 LE07_L1TP_046029_20000808_20161001_01_T1_B[#] Google Earth historic photo from July 22, 2000 Study Area: Portland RLIS

Pre-Process Projected imagery and data frame to WGS 1984 UTM Zone 10N Removed stretch function from raster function for both images Applied apparent reflectance function to both images Create a study area feature and define study area

True color Images 2000: 2017:

False color (urban) Band Combinations 2000: (7,5,3,) 2017: (7,6,3) Urban areas appear purple, developed light green and white, green space green and dark green, and water blue. Unique classification signature file used for each year

Classified images 2000: Large red area here is where clouds were present. Using base map for accuracy eye test, these values did not appear to hurt results

results

Results Urban land use change: 4,635,876 square meters Developed land use change: -5,228,330 square meters Green space land use change: 839,595 square meters

accuracy Possible accuracy issues Solutions Images at 30 meter resolution Reference and image quality for classification varies due to improved technology between landsat 7 and 8 Possible for some inaccurate pixel classification Polygons have different geometry than raster groups, which themselves are relative Solutions Use images with higher resolutions (Ex. aerial imagery rather than satellite imagery) Increase number of samples when training image classification