Remote Sensing of Our Environment Using Satellite Digital Images to Analyze the Earth’s Surface 1

Remote Sensing Definition Remote sensing is the small- or large-scale acquisition of information of an object or phenomenon, by the use of either recording or real-time sensing device(s) that are wireless, or not in physical or intimate contact with the object. 2

Remote Sensing Definition (cont) In practice, remote sensing is the stand-off collection through the use of a variety of devices for gathering information on a given object or area. Examples include: Aircraft PET Spacecraft X-Ray Ships Space Probes MRI 3

Remote Sensing Remote sensing makes it possible to collect data on dangerous or inaccessible areas. 4

Data Acquisition Techniques There are two main types of remote sensing: – passive remote sensing and –active remote sensing. Passive sensors detect natural radiation that is emitted or reflected by the object or surrounding area being observed. Active sensors emit energy at an object and records the energy reflected back to the sensor 5

Wavelength Units of Measurements 6

CIR Film at Close Range 7

Air Photos 8

Artist’s Rendition of SPOT Satellite 9

EMR In remote sensing, information transfer is accomplished by use of electromagnetic radiation (EMR). 10

Electromagnetic Radiation 11

12

Electromagnetic Spectrum 13

14

Geraniums - Normal Color Film 15

Geraniums - CIR Film 16

Normal Color/CIR Comparison 17

Thermal Radiometer 18

Archeology Site - South Dakota 19

Big Brother Watching….. 20

Interactions between Matter and Electro-magnetic Radiation All matter reflects, absorbs, penetrates and emits electro-magnetic radiation in a unique way. For example, the reason why a leaf looks green is that the chlorophyll absorbs blue and red spectra and reflects the green spectrum 21

Types of Remote Sensing with Respect to Wavelength Regions Remote sensing is classified into three types with respect to the wavelength regions; –(1)Visible and Reflective Infrared Remote Sensing, –(2)Thermal Infrared Remote Sensing and –(3)Microwave Remote Sensing 22

Spectral Reflectance of Land Covers Spectral reflectance of vegetation, soil and water 23

Spectral Signatures 24 At what one wavelength does there appear to be maximum separability?

Spectral Reflectance of Land Covers Spectral reflectance of different kinds of trees 25

Landsat MSS - Where?? 26

Where? 27

Where? 28

Where? 29

Where? 30

Gemini Film Image 31

What Season? 32

See the Line? 33

Significant Variations in Land Cover and Land Use 34

Ready to Go! 35

What Scale? 36

MSS vs. TM 37

SPOT - Washington DC 38

Pacman Farm…. 39

Gharb, Morocco 40

Gharb - Pre-Harvest 41

Gharb - Post-Harvest 42

Sakur, Japan 43

Chernobyl

Ocean Measurements 45

California Mosaic 46

Resolution Spectral Resolution Radiometric Resolution Spatial Resolution Temporal Resolution 47

Landsat MSS Spectral Resolution –Band 4 (0.5 – 0.6 um, green) –Band 5 (0.6 – 0.7 um, red) –Band 6 (0.7 – 0.8 um, photo IR) –Band 7 (0.8 – 1.1um, near IR) Radiometric Resolution –1 byte (256 levels (0 – 255)) Spatial Resolution –80m (260ft) Temporal Resolution –16 days 48

Landsat MSS Orbital altitude – 570 miles FOV – 115 mile swath 49

SPOT Spectral Resolution –Band 1 (0.50 – 0.59 um, green) –Band 2 (0.60 – 0.68um, red) –Band 3 (0.79 – 0.89um, RIR) Radiometric Resolution –1 byte Spatial Resolution –20m Temporal Resolution –26 days vertically downward. Can move mirror 27 0, increasing repeatability to 7x in 26 days. 50

SPOT Orbital altitude – 516 miles 73 mile swath 51

Commercialization of Space Remote Sensing Here is a SpaceImaging high resolution panchromatic scene that shows the pyramids outside of Cairo, Egypt 52

Quickbird-2 is the flagship of Digital Globe The Pentagon (a year after it was damaged by a terrorist air assault) on the Virginia side of the Potomac River outside Washington, D.C. 2.8m spatial resolution. 53

IKONOS 1999 launch Spatial Resolution: –B/W: 82-cm –Multispectral: 4-meter 54

IKONOS Spectral Range –526–929 nm 445–516 nm (blue) 506–595 nm (green) 632–698 nm (red) 757–853 nm (near IR) Revisit Time –Approximately 3 days 55

GeoEye-1 and IKONOS Comparison Satellite FeatureGeoEye-1IKONOS Panchromatic Resolution.5-meter1-meter Multispectral Resolution1.64-meter3.28-meter Spectral RangeR G B IR Launch Date9/6/089/24/99 Orbit Altitude681-km/423-miles681-km/423/miles 56

GeoEye-1: Ayers Rock 57

GeoEye-1: Canyonlands, Utah 58

GeoEye-1: El Capitan 59

GeoEye-1: Kenai Fjords National Park, Alaska 60

GeoEye-1: The Moon 61

GeoEye-1: Niagara Falls 62

GeoEye-1: Rainbow Bridge, Utah 63

GeoEye-1: Nile River Delta 64

GeoEye-1: Burning Man

GeoEye-1: Burning Man

GeoEye-1: Sand & Gravel Plant Arkansas 67

GeoEye-1: Sand & Gravel Plant Arkansas 68

Aster: Yukon Delta 69

Military Intelligence Satellites The KH-12 series, the last for which some specifications can be found, is reputed to achieve a resolution of 2+ cm, although images of this sharpness haven't been released. 70

US Spy Imagery Sources U-2 SR-71 TARPS (Tactical Airborne Reconnaissance Pod System) ATARS (Advanced Tactical Airborne Reconnaissance System) Predator UAV TESAR (Synthetic Aperture Radar) Predator UAV Electro-optical KH-4 CORONA KH-5 ARGON KH-11 KENNAN/CRYSTAL KH-12 IMPROVED CRYSTAL 71

Spatial Resolution Detection vs.Recognition 72

NYC Landsat TM 73

Landsat 5 NYC (summer 1997) 74

ASTER: NYC - 9/22/02 75

Digital Images 76 Colors present are additive mixes of two or more primaries (e.g., yellow is a mix of red and green; orange is a mix of more red and some green; white is an equal mix of all three primaries, and black is simply the absence of any colored light of any wavelength). The colors that result from combinations of blue, green, and red (the primaries) are indicated in this additive color diagram.

NY Area Landsat MSS 77

NY Area Landsat MSS 78

Digital Image Construction 79