1. Introduction to Remote Sensing

2. Outline What is remote sensing? The electromagnetic spectrum (EMS) The four resolutions Image Classification Incorporation with GIS Sample Research

3. What is remote sensing? Remote sensing is the art and science of analyzing the Earth’s surface with remotely acquired data (most often from aircraft or satellites)

4. Electromagnetic Spectrum

5. Remote sensing instruments can collect reflectance information in a wide range of the spectrum (visible, infrared, radar) Different features reflect various amounts of energy from different parts of the spectrum That is how we can distinguish and separate between features.

6. Spectral Reflectance of common features

7. The Four Resolutions Spectral Resolution Refers to the section(s) of the EMS in which reflectance information is acquired For example, the Landsat ETM+ sensor collects: -blue -mid infrared -green -mid infrared -red -thermal infrared - near infrared - panchromatic

8. The Four Resolutions Spatial Resolution Refers to the size of a single pixel in an image (i.e., the area for which individual reflectance values are recorded Landsat ETM+ - 30 m IKONOS Panchromatic– 1 m

9. The Four Resolutions

10. Radiometric Resolution Refers to the range of reflectance values recorded For example, 8-bit data displays values ranging 0-255 ( 2 8 =256 ) Temporal Resolution Refers to how often an image of the same area is collected, as determined by the sensor’s orbit and spatial resolution

11. Classification The process of converting raw imagery to thematic information Each pixel in the image gets placed into a certain class based on its reflectance compared to other pixels

12. Raw Image

13. Classified Image

14. Change Detection Using images of the same area at different times to analyze what has happened between the two dates Landsat- 1985 Landsat- 2000

15. Change Detection

16. GIScience Geographical Information Sciences (i.e., the art and science of spatial analysis) Data collected from a variety of sources can provide input for a GIS database because (provided) they are rectified to a common spatial reference (coordinate system, datum plane, projection) (e.g., WGS 1984, UTM, Zone 30 ) This includes remotely-sensed data

17. Image Backdrops While classified imagery can be used as a layer in the GIS, raw imagery is often used as a backdrop for displaying point, line and polygon information

18. Questions?