1. By: Reid Swanson Sam Soper

2. Goal: To describe land cover/use changes that have occurred in the Twin Cities Metro-Area from the 1991 to 2005 Quantifying the increase in impervious surface Applications for which this type of study would be useful:

3. Data Rectification Classification Change Detection Accuracy

4. Data Classification image: Multispectral image provided by Joe Knight Reference images: 1991: Most of the state was flown in spring of 1991; the remainder was completed spring 1992. Photos are available in both color-infrared and black-and-white; the latter were used to produce statewide digital orthophotos The original images from both flights are 9" x 9" and cover about 25 square miles at an approximate scale of 1:40,000

5. Data Reference images: 2005: a 2006 image taking in Summer - Fall MDA natural color 1-meter USGS procured photos from MDA for public distribution. Twin Cities 2006 Spring USGS natural color 0.3-meter Minneapolis - St. Paul area

6. 1991

7. 2005

8. Rectification Regular linear features (ex. Roads) lined up  GOOD Area did not match up  Subset Image Some atmospheric interference  creation an unclassified class

9. 1991-No Subset

10. 1991-Subset

11. 2005- No Subset

12. 2005-Subset

13. Cloud Interference

14. Classification Unsupervised classification Maximum likelihood-(grouping pixels to nearest class mean) 20 spectral responses  Need more variation between classes 40 spectral responses  Recoded into 7 distinct classes Classes: Urban Forest Green Space Agriculture Water Wetland Unclassified

15. Classification PROBLEM  recode needs to work Couldn’t run thematic change detection Need same # of classes Output results wouldn’t have been clear Addition problems with accuracy assessment

16. Change Detection Plan: Thematic Change Detection Results in “from-to” change Actual: Manual interpretation of histogram values Digital number comparison Allows us to see the magnitude of change, but not “from-to”

17. Change Detection

18. Change

20. Accuracy Assessment Reference data : 1991: Most of the state was flown in spring of 1991; the remainder was completed spring 1992. Photos are available in both color-infrared and black-and-white; the latter were used to produce statewide digital orthophotos The original images from both flights are 9" x 9" and cover about 25 square miles at an approximate scale of 1:40,000 2005: a 2006 image taking in Summer - Fall MDA natural color 1-meter USGS procured photos from MDA for public distribution. Twin Cities 2006 Spring USGS natural color 0.3-meter Minneapolis - St. Paul area

21. Accuracy Assessment Generated X,Y coordinates in ERDAS Sampling method: Simple random Exported to ARCMAP MANUAL MANIPULATION OF ACCURACY DUE TO RECODE FAILURE Allowed ourselves to see classification data Compared classified to reference data  Error Matrix(by hand!)

22. Reference Points- State layer

23. Reference Points- City layer

24. Error Matrix 1991

25. Error Matrix 2005

26. Minimum Mapping Unit 30 meters

27. Applications: Change in impervious surface (urban areas) and its impacts on water quality Identifying areas of population increases  examine commuter effect on carbon emissions

28. Water Quality

29. Woodbury, MN

30. Conclusion Despite program errors our data allows us to see the change in cover type as a result of population growth and human expansion 198 more km^2 of urban area in 2005 This information can useful in application to a variety of studies

31. Thanks!!!!!