1. Introduction to Remote Sensing
1. Introduction to Remote Sensing
Definition of Remote Sensing
• Obtaining information about Earth’s surface from measurements, by aircraft or satellite sensors, of radiated energy
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1. Introduction to Remote Sensing
Remote Sensing Process
Surface
Major Objective of Remote Sensing
Detect, measure, record and analyze energy radiated in selected wavelengths of the electromagnetic spectrum
0.4 Gamma X-Rays Rays UV 0.7 3 15 µm 1m
Visible Reflective Thermal Infrared Infrared
Microwave
Near IR
Middle IR
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1. Introduction to Remote Sensing
Synoptic “Bird’s Eye” View
Overview of Remote Sensing
Energy Source
Atmospheric Absorption and Scattering
Image
Sensor
Reflectance
Absorption Transmittance
Interpretation and Analysis
Landscape
Information: maps and statistics for Applications
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1. Introduction to Remote Sensing
Physical Basis for Remote Sensing
The distinctive character of electromagnetic radiation reflected or emitted from natural and human-made objects and scenes
Spectral Reflectance of Basic Cover Types
Green Vegetation Light Soil Dark Soil Turbid Water Clear Water
Multi-Temporal Images
May 6 August 29 September 14
IKONOS Imagery
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1. Introduction to Remote Sensing
Variations in electromagnetic fields that can be used to identify and characterize objects:
Sources of Information
• Spectral-radiometric (color, temperature) • Spatial (pattern, size, shape, texture, ...) • Temporal
What Information Can Be Remotely Sensed ?
Fundamental Variables
• • • • • • • • Planimetric (x,y) location and dimensions Topographic (z) location Color (spectral reflectance) Surface temperature Texture Surface roughness Moisture content Vegetation biomass
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1. Introduction to Remote Sensing
Examples of Remote Sensing Imagery
• Aerial photography • Digital imagery
Weather Satellite (GOES) Imagery
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1. Introduction to Remote Sensing
Weather Satellite (GOES) Imagery
Large scale B&W aerial photo
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1. Introduction to Remote Sensing
Color Infrared Aerial Photo
High Altitude Color Infrared Aerial Photo
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1. Introduction to Remote Sensing
Mosaic of Minnesota Landsat images
Landsat TM Image
7-County Twin Cities Metropolitan Area
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1. Introduction to Remote Sensing
Enlarged area of previous Landsat image, east of St. Paul (Woodbury, MN)
IKONOS satellite, high-resolution, false color
image of northeast Woodbury
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1. Introduction to Remote Sensing
IKONOS satellite, high-resolution, color
image of northeast Woodbury
Digital color 1-meter ortho imagery
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1. Introduction to Remote Sensing
NOAA AVHRR Imagery
April 7, 2002 July 1, 2002
Spring and summer images of Minnesota acquired by the Terra satellite
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1. Introduction to Remote Sensing
Surface Temperatures - AVHRR Imagery
Global Monitoring of Vegetation and Oceans (SeaWIFS data)
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1. Introduction to Remote Sensing
Uses of Remotely Sensed Images
1. Base on which other information can be portrayed 2. Delineate patterns (i.e., mapping) 3. Determine extent and areas of different categories (i.e., inventory) 4. Quantitative measurement of landscape properties
Advantages of Remote Sensing
1. Improved vantage point, synoptic view 2. Broadened spectral sensitivity 3. Increased spatial resolution 4. 3-D perspective 5. Capability to stop action 6. Historical record 7. Comparability of data 8. Rapid data collection 9. Quantitative analysis 10.Ability to extend ground observations 11.Cost savings
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1. Introduction to Remote Sensing
Applications of Remote Sensing
• Agriculture, Forestry and Range
– – – – Identify crop, forest and rangeland types Measure area Assess condition and estimate yields Monitor changes
• Water Resources
– Lake water quality monitoring – Inventory and mapping of wetlands
• Monitor land use and change
– Urban Dynamics
• Mapping soils, geology, topography
History of Remote Sensing
Photographic image formed Photography from balloons First photography from airplane Initial development of photogrammetry and applications of aerial photography • 1940’s Initial development of infrared and radar sensing • 1956 Research on crop disease detection with infrared photography • • • • 1839 1850’s 1909 1920’s
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1. Introduction to Remote Sensing
History of Remote Sensing, cont.
• 1960 “Remote Sensing” term first used • 1960 TIROS weather satellite launched • 1965 Airborne multispectral scanner data becomes available for civilian research • 1972 Launch of Landsat 1 • 1982 Landsat-4 w/ Thematic Mapper launched • 1986 SPOT satellite launched • 1999 First U.S. high resolution commercial satellite successfully launched • 1999 Launches of Landsat-7 and Earth Observing System (Terra satellite)
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