1. Land Use / Land Cover Change in the Phoenix Metropolitan Area 1984 - 2011 Lori Krider & Melinda Kernik 19842011

2. Introduction Why Phoenix? o One of 10 fastest growing cities from 1990 - 2000 (Perry & Mackun, 2001) o Arid regions with high population are water stressed o Water use is reflected by how the land is used and managed o How is the landscape changing and how does this effect water use?

3. Objective Use remote sensing software to assess land use / land cover change in Phoenix from 1984 – 2011 o Expect to see dramatic changes due to rapid population growth  Increase in urban and suburban areas (sprawl)  Increase in cultivated areas on edges of metropolitan area  Decrease in natural vegetation

4. Objective Study Area o Phoenix-Mesa Metropolitan Area  South-central Arizona  16,200 km 2  Phoenix, Mesa, Tempe, Chandler, Gilbert, Scottsdale, Glendale, Sun City, Peoria, and Avondale Google Maps

5. Preparation Tools: ERDAS IMAGINE 2011, USGS GLOVIS, ArcGIS 10, Google Maps TM and Google Earth TM Materials: Landsat TM images from 1984 and 2011 (two from each year, 30 m res., 7 bands, June), 2006 NLCD Pre-classification processing o Stack bands, mosaic and crop images for each year o View NLCD o Unsupervised classification (5, 6 & 7 classes)

6. Analysis Supervised classification o Anderson Hierarchical Classification (levels 1 and 2)  Altered, unaltered, developed and water  Altered  Human-assisted: healthy and stressed crops, golf courses  Uncultivated: fields not reflecting in IR  Unaltered  Natural: upland and scrub/shrub (not in IR)  Hydrophillic vegetation: depressional vegetation often associated with water (in IR)  Water: lakes, rivers and large golf course water hazards  Developed  suburban (dwellings) & urban/roads (commercial/industrial)

7. Analysis Training Areas o 15 - 45 o Why?  Errors in first run with less training areas  Combination of smaller category classes (i.e. healthy crop + stressed crop)  Reduce confusion and capture variety Change Detection o Thematic: 1984 -> 2011 o Difference  to identify areas of significant change and overall patterns  10, 20, and 30% thresholds

8. Post-classification Accuracy Assessment o stratified random o same mosaics as reference  added Google Maps TM for 2011 o switched "trainers" o 140 reference points (20 per class) http://www.cartoonstock.com/directory/b/bad_appraisal.as p

9. 19842011

10. Purple: Change to Suburban Light Blue: Change to Urban Thematic Change Detection

11. 1984

12. 2011

13. Purple = changed to Suburban Blue = changed to Urban

14. Green = more than 20% increase in NIR Blue = more than 20% decrease in NIR

16. Thematic Change Detection

17. 1984 2011 Limitations!

18. Accuracy Assessment

19. For future classifications: Clip to the smallest possible boundaries – More ontological classes = more classification confusion Complications using 30m resolution images for reference data and the same image. Use this technique, to generate water infrastructure policy for Phoenix  …probably not

20. References 1.Perry, M. J. & P. J. Mackun. Population Change and Distribution 1990 - 2000: Census 2000 Brief. April 2011. United States Census Bureau. 12 Nov. 2011..