Tutorial 1: Remote SensingRemote Sensing: Platforms, physics, data,

data availability and acquisition

IAI Summer Institute

mbinford@geog.ufl.edu

Landscape Change

Definition of Remote Sensing

¥ The acquisition and measurement of data/information onsome property(ies) of a phenomenon, object, or material bya recording device not in physical, intimate contact withthe feature(s) under surveillance; techniques involveamassing knowledge pertinent to environments bymeasuring force fields, electromagnetic radiation, oracoustic energy employing cameras, radiometers andscanners, lasers, radio frequency receivers, radar systems,sonar, thermal devices, seismographs, magnetometers,gravimeters, scintillometers, and other instruments.

¨ Source: NASA tutorial on remote sensing:http://rst.gsfc.nasa.gov/Intro/nicktutor_I-1.html

Definition of Remote Sensing

¥ Whew!

¥ Better: Sensing for measurement from a distance.

—Hearing, seeing, smelling are all remotesensing, but here we focus on one kind:

—Measurement, by satellite-borne sensors, of theelectromagnetic energy reflected or emittedfrom objects on the Earth s surface.

Source of image: http://rst.gsfc.nasa.gov/Intro/nicktutor_I-1.html

Nature of Remote Sensing Data

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Multiple Bands of Satellite DataLandsat 4 & 5 data consist of seven layers of data

Combining Bands in Clever Ways

5-4-3 Color Composite: Band 5=Red, 4=Green, 3=Blue

What Else Can Be Done with RS Data?

NDVI = (IR - Red)(IR + Red)

-1 to +1

What do those numbers mean?Electromagnetic Spectrum of Radiant Energy

Short WavelengthHigh FrequencyHigh Energy

Long WavelengthLow FrequencyLow Energy

Solar and Terrestrial EnergyDistribution by Wavelength

Some Light Is Reflected

Albedo: reflective quality of a surface, expressed as percent of incident light reflected.

Some Light is Scattered

Need figure of light scattering

Source: http://covis1.atmos.uiuc.edu/guide/optics/html/scattering.html

Rayleigh ScatteringMie Scattering

Some Light is Absorbed

Need image of absorption

Atmospheric Alteration of Radiant Energyand Pathways from the Sun to the Sensor

Absorbance/Reflectance Spectrum

Spectra of Different Materials

USGS Spectral Library http://speclab.cr.usgs.gov/spectral-lib.html

Platforms and Instruments

SPOT 4

Landsat 7 Artist s Impression

AVHRR

Remote Sensing Platforms HaveBeen Designed to Sense

Electromagnetic Energy inVarious Bands in Order to Take

Advantage of TheAbsorption/Transmission

Properties of the Atmosphere

Example: MSS

AVHRR

Advanced Very-High Resolution Radiometer

AVHRR

Advance Very High Resolution Radiometer.

NOAA Polar Orbiting Environmental Satellites (POES)

Spatial Resolution = 1.1km

Temporal Resolution = Daily

Spectral Range and Resolution

Band NOAA-6,8,10 NOAA-7,9,11,14

Nbr. IFOV

1 0.58 - 0.68 0.58 - 0.68 1.39

2 0.725 - 1.10 0.725 - 1.10 1.41

3 3.55 - 3.93 3.55 - 3.93 1.51

4 10.50 - 11.50 10.3 - 11.3 1.41

5 band 4 repeated 11.5 - 12.5 1.30

(micrometers) (micrometers) (milliradians)

Landsat Series

Landsat Series

Landsat7 ETM+

Landsat Program - System Summary

This table, and most of the Landsat 7 images were taken from the Landsat 7 Science DataUser s Book: http://ltpwww.gsfc.nasa.gov/IAS/handbook/handbook_toc.html

Ground Receiving Stations

Landsat 4, 5

Landsat 4 and 5 and TM Characteristics:

Band Number Spectral Range(microns) Ground Resolution(m) 1 .45 to .52 30 2 .52 to .60 30 3 .63 to .69 30 4 .76 to .90 30 5 1.55 to 1.75 30 6 10.40 to 12.5 60? 7 2.08 to 2.35 30

Swath width: 185 kilometers Repeat coverage interval: 16 days (233 orbits) Altitude: 705 kilometers Quantization: 8 Bit, 256 levels On-board data storage: ? Recording Tape Inclination: Sun-synchronous, 98.2 degrees Equatorial crossing: Descending node; 10:00am +/- 15 min. Launch vehicle: Various Launch date: 1 March 1984 (5), 16 July 1982 (4)

Landsat 4 and 5 and TM Band Applications:

Color Band (µm) Application

Blue 0.45 - 0.52 Soil/vegetation discrimination, deciduous/coniferous forest differentiation, clear-water bathymetry

Green 0.52- - 0.60 Growth/vigor indication for vegetation,sediment estimation, turbid-water bathymetry

Red 0.63 - 0.69 Crop classification, ferric iron detection, ice and snow mapping

Near Infrared (NIR) 0.76 - 0.90 Biomass surveys, water-body delineation

Short-wave IR 1.55 - 1.75 Vegetation moisture, snow-cloud differentiation

Short-wave IR 2.08 - 2.35 Hydrothermal mapping, rock/soil type discrimination for mineral and petroleumgeology

Thermal IR 10.4 - 12.5 Thermal mapping, plant stress, urban/non-urban land-use differentiation

Source: Mika, A.M. Three decades of Landsat instruments. PE & RS. 43:839 - 852.

Landsat 7

Landsat 7 and ETM+ Characteristics:

Band Number Spectral Range(microns) Ground Resolution(m) 1 .45 to .515 30 2 .525 to .605 30 3 .63 to .690 30 4 .75 to .90 30 5 1.55 to 1.75 30 6 10.40 to 12.5 60 7 2.09 to 2.35 30 Pan .52 to .90 15

Swath width: 185 kilometers Repeat coverage interval: 16 days (233 orbits) Altitude: 705 kilometers Quantization: Best 8 of 9 bits On-board data storage: ~375 Gb (solid state) Inclination: Sun-synchronous, 98.2 degrees Equatorial crossing: Descending node; 10:00am +/- 15 min. Launch vehicle: Delta II Launch date: February 1999

SPOT

SPOT, TM, MSS Comparative ChartAVHRR Bands

Orbital Patterns

Orbital Patterns

SPOT Orbital Patterns

And Ground Receiving Stations

GOES

http://www.nnic.noaa.gov/SOCC/gifs/GOESsys.gif

Newer Satellite Platforms

¥ Shuttle: SIR-C/SAR

¥ MODIS

¥ ASTER

¥ RADARSAT

¥ See NASA NRA Appendix F for LongerList (link in GEO 5145c syllabus)

Active Sensors

¥ Microwave Radar—Airborne

—Satellite Borne¥ ERS-1

¥ JERS-2

Remote Sensing Data

Data Availability and Acquisition¥ Emphasis on Landsat TM, MSS; SPOT; AVHRR¥ Landsat - EOSAT (Space Imaging), USGS (EROS Data

Center)¥ SPOT - SPOT Image Corp.¥ AVHRR - Advanced Very High Resolution Radiometer

(Spectral, not Spatial Resolution); Satellite by NationalOceanic and Atmospheric Administration (NOAA). Muchdata available form USGS EROS, other sources

¥ Others (See Space Imaging Site:http://www.spaceimage.com/—JERS—Indian (IRS)—etc.

Finding Your Scene(s)¥ Worldwide Reference Systems

— See http://www.clas.ufl.edu/users/mbinford/geo5145/fltm_scene.gif for theexample for Florida - Pointer on class web site.

— Path-Row Notation¥ The combination of a Path number and a Row number uniquely

identifies a nominal scene center. The Path number is always givenfirst, followed by the Row number. The notation 127-043, forexample, relates to Path number 127 and Row number 043.

¥ WWW Resources (seehttp://www.clas.ufl.edu/users/mbinford/geo5145/RemoteSensingDataSites.html

pointer on class web site)— SPOT Image— Space Imaging EOSAT— EROS Data Center

EROS DATA CENTER

http://edcwww.cr.usgs.gov/

SpaceImaging (EOSAT)

http://www.spaceimage.com/

SPOT Image

http://www.Spotimage.fr/

Another Source of Data for SomeAreas

¥ Michigan State University Tropical ForestInventory Project ($25 per TM scene, $50per ETM+ scene, for selected scenes fromAmazonia, Africa, and southeast Asiatropical forests).

¥ URL:http://www.bsrsi.msu.edu/trfic/index.html

Exercise: FIND YOUR SCENES

¥ Figure out where your study area is:—Latitude/Longitude—Path/Row in Landsat or SPOT WRS

¥ Go to data provider site, search archives¥ Have a look at images until you get several (3-4)

that meet your criteria (aha! Criteria? What is theQuestion?)

¥ List the Scene ID, t he date of acquisition, andthe Row/Path identifier.