Intro to Remote Sensing

Lecture 1

August 25, 2004

What is remote sensing?

Take a photo

What is remote sensing

Remote Sensing: remote sensing is science of acquiring, processing, and interpretingimages and related data that are obtained from ground-based, air-or space-borne instruments that record the interaction between matter (target) and electromagnetic radiation.

Remote Sensing: using electromagnetic spectrum to image the land, ocean, and atmosphere.

In this class, we will mostly focus on the the principles and techniques for data collection and the interaction of

electromagnetic energy with the Earth's surface (2/3 of the time) some application examples (1/3 of the time)

Electromagnetic Spectrum

Source: http://oea.larc.nasa.gov/PAIS/DIAL.html

Remote sensing platforms Remote sensing platforms

Ground and Aircraft Based

Ground repeat or continuous sampling regional or local coverage example: NEXRAD for precipitation

Aircraft repeat sampling , any sampling interval regional or local coverage examples: AVIRIS for minerals exploration

LIDAR for ozone and aerosols

Space Based

Sun-synchronous polar orbits global coverage, fixed crossing, repeat sampling typical altitude 500-1,500 km example: MODIS, Landsat

Low-inclination, non-Sun-synchronous orbits tropics and mid-latitudes coverage, varying sampling typical altitude 200-2,000 km example: TRMM

Geostationary orbits regional coverage, continuous sampling over equator only, altitude 35,000 km example: GOES

Types of remote sensing

Passive: source of energy is either the Sun or Earth/atmosphere Sun

- wavelengths: 0.4-5 µm

Earth or its atmosphere

- wavelengths: 3 µm -30 cm

Active: source of energy is part of the remote sensor system Radar

- wavelengths: mm-m Lidar

- wavelengths: UV, Visible, and near infrared

LANDSAT MSS/TM/ETM+ (NASA, USA) SPOT-1, -2, -3 (France) JERS-1 (optical sensor) (Japan) MODIS (NASA, USA) CMODIS (China) AVHRR (NOAA, USA) ASTER (NASA, USA, and Japan) IRS-1A, -1B, -1C, 1D (India) IKONOS (Space Imaging, USA)

Major Passive:Major Passive: Multi-Spectral SensorsMulti-Spectral Sensors

Hyper-Spectral SensorHyper-Spectral Sensor

AVIRIS (NASA, USA)HyMap (Australia)

SIR-A, -B, -C (NASA, USA) RADARSAT (Canada) JERS-1 (radar sensor) (Japan) ERS-1 (European) AIRSAR/TOPSAR (NASA, USA) NEXRAD (NOAA, USA) TRMM (NASA, USA)

Major Active:Major Active: Radar SensorRadar Sensor

Lidar SensorLidar Sensor ALTMS (TerraPoint, USA) FLI-MAP (John Chance, USA) ALTM (USA) TopoEye (USA) ATLAS (USA)

Measurement scales constrained by physics and technology

Spatial resolution (IFOV/GSD) and coverage (field-of-view) Optical diffraction sets minimum aperture size

Spectral resolution ( ) and coverage (min to max) Narrow bands need bigger aperture, more detectors, longer

integration time

Radiometric resolution (S/N, NE, NET ) and coverage (dynamic range) Aperture size, detector size, number of detectors, and integration time

Temporal resolution (revisit) and coverage (repeat) Pointing agility, period for full coverage

Spatial Spatial ResolutionResolution

Spatial Spatial ResolutionResolution

Jensen, 2000Jensen, 2000

163 NEXRADs in the USA

First deployed in 1988

Spectrum covrageMicrowave (10cm)

SpatialResolution (km)1, 2, 4

Spatial coverage (km)Radius of 230km TemporalResolution 6-10 minutes

NEXRAD coverage of the San Antonio area NEXRAD has verygood coverage (maximum 230 kmin radius) in the SA area

Click here: http://weather.noaa.gov/radar/national.html for real time precipitation

NASA Landsat-7 (ETM+) launched 4/15/1999

Spectrum coverage (8 bands)VisibleNear Infrared Thermal Infrared

Spectrum resolution50-200 nm

Spatial resolution (m)15, 30, 60

Swath (km)185

Temporal resolution16 days

Radiometric resolution8 bits

705 km

Terra satellite launched on Terra satellite launched on 12/18/199912/18/1999

http://terra.nasa.gov/About/MODIS/modis_swath.html

Spectrum coverage (36 bands)VisibleNear Infrared Thermal Infrared

Spectral resolution10-500 nm

Spatial resolution (m)250, 500, 1000

Swath (km)2400

Radiometric resolution12 bits

705 km

IKONOS launched on 9/24/1999

Spectrum coverage (4 +1 bands)VisibleNear Infrared Panchromatic

Spectral resolution65-95 nm, 403 nm

Spatial resolution (m)4 and 1

Swath (km)11

Radiometric resolution11 bitshttp://www.spaceimaging.com/

Source: http://www.ceosr.gmu.edu/CSI759S01/speaker/04.Dr.Chiu/CSI_759_Summer_2001_04Chiu/sld045.htm

first satellite rain radar to measure the 3-D of precipitation over the tropics between 35º latitude, since 1997

Wavelength 2.2 cm (13.8 GHz),4 km resolution and swath of 220 kmTemporal: daily

Global Geostationary Environmental SatellitesGlobal Geostationary Environmental Satellites

Europe and Africa

N. & S. American Eastern Pacific

Jap. Aus. W. Paci

C. Asia, India Ocean China, India Ocean

Earth radius 6,370 kmSatellite altitude 35,800 km

3.9 and 10.7 µm4 km, continuous?

The size of a cell we call image resolution, depending on…Such as 1 m, 30 m, 1 km, or 4 km

History of Remote Sensing Aerial photography is the original form of remote sensing (using visible spectrum) started in

1909 Aerial photographic reconnaissance was widely used after 1915 in WWI. Photogrammetric Engineering, the official monthly publication of the American Society of

Photogrammetry, was first published in 1934. Color infrared photography began 1931, then was widely used in agriculture and forestry. Development of radar (1930-1940). During WWII, non-visible spectrum (infrared and radar) were used as tools in remote

sensing. After the first man-made satellite (Sputnik 1) was launched on 4 October 1957, remote

sensing moved to outer space. The United States' Explorer 6 transmitted the first space photograph of the Earth in August

1959. The first systematic meteorological satellite observation came with the launch of the United

States' TIROS 1 in 1960. Landsat 1 (originally called the Earth Resources Technology Satellite or ERTS) was the first

satellite to collect data on the Earth's natural resources. It was launched on 23 July 1972. Hyperspectral remote sensing emerged (1980s), widely used in mineral, oil, etc. exploration. Since then, a large number and advanced types of remote sensing systems have been

developed.

Remote Sensing Applications

Land: rocks, minerals, faults, land use and land cover, vegetation, DEM, snow and ice, urban growth, environmental studies, …

Ocean: ocean color, sea surface temperature, ocean winds, …

Atmosphere: temperature, precipitation, clouds, ozone, aerosols, …

Applications driving remote sensing 100

50

30

20

10

80

8

5

3

2

10.8

0.5

0.3

0.2

0.4

0.60.7

Nom

inal

Sp

atia

l Res

olu

tion

(g

rou

nd

res

olve

d d

ista

nce

, met

ers)

Land Cover Class Level

I II III IV

4

6 7

40

60 70

0.1

I

II

III

IV

100

50

30

20

10

80

8

5

3

2

10.8

0.5

0.3

0.2

0.4

0.60.7

Nom

inal

Sp

atia

l Res

olu

tion

(g

rou

nd

res

olve

d d

ista

nce

, met

ers)

Land Cover Class Level

I II III IV

4

6 7

40

60 70

0.1

I

II

III

IV

2 y3 y4 y

Quickbird (2000) 0.82 x 0.82 3.28 x 3.28

0.2 1.0 2 3 5 10 2 3 5 102 103 104 2 3 5 2 3 5

10

102

103

104

2 3

5

8

2 3

5

2

3

5

2

3

5

2

3

5

9 d

1 d

1 hr

1 m 10 30 100 m 1 km

1000 m 5 km 10 km

12 hr

8105

8

8

8

.80.5

3 d

2 d

4 d

532

2

3

58

106

1 y

23

5

8107

5 y

10 y

15 20

4 8

26 d

44 d 55 d

METEOSAT VISIR 2.5 x 2.5 km

TIR 5 x 5 km

AVHRR LAC 1.1 x 1.1 km

GAC 4 x 4 km

JERS-1 MSS 18 x 24

L-band 18 x 18

Aerial Photography < 0.25 x 0.25 m (0.82 x 0.82 ft.)

1 x 1 m (3.28 x 3.28 ft.)

RADARSAT C-band 11-9, 9 25 x 28

48-30 x 28 32-25 x 28

50 x 50 22-19 x 28 63-28 x 28 100 x 100

EOSAT/Space Imaging IKONOS (1999)

Pan 1 x 1 MSS 4 x 4

IRS-P5 (1999) Pan 2.5 x 2.5

ORBIMAGE

OrbView 3 (1999) Pan 1 x 1 MSS 4 x 4

OrbView 4 (2000) Pan 1 x 1 MSS 4 x 4

Hyperspectral 8 x 8 m

22 d 16 d

IRS-1 AB LISS-1 72.5 x 72.5

LISS-2 36.25 x 36.25 IRS-1CD

Pan 5.8 x 5.8 LISS-3 23.5 x 23.5; MIR 70 x 70

WiFS 188 x 188

10,000 min

100 min

5 d

30 d

180 d

T3

C1

15 y

DE1, E2

T4

0.3

LANDSAT 4,5 MSS 79 x 79 TM 30 x 30

LANDSAT 7 ETM+ (1999) Pan 15 x 15; MSS 30 x 30

TIR 60 x 60

E1

L4

M5

T1, U1

LI

SPOT HRV 1,2,3,4 Pan 10 x10

MSS 20 x 20 SPOT 5 HRG (2001; not shown)

Pan 2.5 x 2.5; 5 x 5 MSS 10 x 10; SWIR 20 x 20

1 m0.3 5 100 m10 20

Nominal Spatial Resolution in meters

30

SPIN-2 KVR-1000 2 x 2 TK-350 10 x 10

C2

DE2

DE3 DE4 DE5

L3

0.5

S2

L2S1

D1 D2

S3

1,000 min

min

Tem

pora

l R

esol

utio

n in

min

utes

SPOT 4 Vegetation

1 x 1 km

T2U2U3

B1

M1M2

ERS-1,2 C-band 30 x 30

GOES VIS 1 X 1 km TIR 8 x 8 km

NWS WSR-88D Doppler Radar

1 x 1 km 4 x 4 km

ORBIMAGE OrbView 2 SeaWiFS

1.13 x 1.13 km

ASTER (1999) EOS AM-1

VNIR 15 x 15 m SWIR 30 x 30 m TIR 90 x 90 m

MODIS (1999) EOS AM-1

Land 0.25 x 0.25 km Land 0.50 x 0.50 km

Ocean 1 x 1 km Atmo 1 x 1 km TIR 1 x 1 km

M3M4

2 y3 y4 y

Quickbird (2000) 0.82 x 0.82 3.28 x 3.28

0.2 1.0 2 3 5 10 2 3 5 102 103 104 2 3 5 2 3 5

10

102

103

104

2 3

5

8

2 3

5

2

3

5

2

3

5

2

3

5

9 d

1 d

1 hr

1 m 10 30 100 m 1 km

1000 m 5 km 10 km

12 hr

8105

8

8

8

.80.5

3 d

2 d

4 d

532

2

3

58

106

1 y

23

5

8107

5 y

10 y

15 20

4 8

26 d

44 d 55 d

METEOSAT VISIR 2.5 x 2.5 km

TIR 5 x 5 km

AVHRR LAC 1.1 x 1.1 km

GAC 4 x 4 km

JERS-1 MSS 18 x 24

L-band 18 x 18

Aerial Photography < 0.25 x 0.25 m (0.82 x 0.82 ft.)

1 x 1 m (3.28 x 3.28 ft.)

RADARSAT C-band 11-9, 9 25 x 28

48-30 x 28 32-25 x 28

50 x 50 22-19 x 28 63-28 x 28 100 x 100

EOSAT/Space Imaging IKONOS (1999)

Pan 1 x 1 MSS 4 x 4

IRS-P5 (1999) Pan 2.5 x 2.5

ORBIMAGE

OrbView 3 (1999) Pan 1 x 1 MSS 4 x 4

OrbView 4 (2000) Pan 1 x 1 MSS 4 x 4

Hyperspectral 8 x 8 m

22 d 16 d

IRS-1 AB LISS-1 72.5 x 72.5

LISS-2 36.25 x 36.25 IRS-1CD

Pan 5.8 x 5.8 LISS-3 23.5 x 23.5; MIR 70 x 70

WiFS 188 x 188

10,000 min

100 min

5 d

30 d

180 d

T3

C1

15 y

DE1, E2

T4

0.3

LANDSAT 4,5 MSS 79 x 79 TM 30 x 30

LANDSAT 7 ETM+ (1999) Pan 15 x 15; MSS 30 x 30

TIR 60 x 60

E1

L4

M5

T1, U1

LI

SPOT HRV 1,2,3,4 Pan 10 x10

MSS 20 x 20 SPOT 5 HRG (2001; not shown)

Pan 2.5 x 2.5; 5 x 5 MSS 10 x 10; SWIR 20 x 20

1 m0.3 5 100 m10 20

Nominal Spatial Resolution in meters

30

SPIN-2 KVR-1000 2 x 2 TK-350 10 x 10

C2

DE2

DE3 DE4 DE5

L3

0.5

S2

L2S1

D1 D2

S3

1,000 min

min

Tem

pora

l R

esol

utio

n in

min

utes

SPOT 4 Vegetation

1 x 1 km

T2U2U3

B1

M1M2

ERS-1,2 C-band 30 x 30

GOES VIS 1 X 1 km TIR 8 x 8 km

NWS WSR-88D Doppler Radar

1 x 1 km 4 x 4 km

ORBIMAGE OrbView 2 SeaWiFS

1.13 x 1.13 km

ASTER (1999) EOS AM-1

VNIR 15 x 15 m SWIR 30 x 30 m TIR 90 x 90 m

MODIS (1999) EOS AM-1

Land 0.25 x 0.25 km Land 0.50 x 0.50 km

Ocean 1 x 1 km Atmo 1 x 1 km TIR 1 x 1 km

M3M4

Various application demands as driving forces for the resolution improvements of remote sensing

Jensen, 2000Jensen, 2000Jensen, 2000Jensen, 2000

Trend and Future of Remote Sensing (1)

High spatial resolution- IKONOS launched in 1999 by Space Imaging

(4 m multi-spectral and 1 m panchromatic)- QuickBird launched in 2001 by DIGITALGLOBE

(2.44 m multi-spectral and 61 cm panchromatic)

High spectral resolution- AVIRIS, 10nm and 20 m, 224 bands- Hyperion launched in 2000, 10nm and 30m, 220

bands High radiometric resolution

- 8 bits to 12 bits High temporal resolution

- GOES 15-30 minutes- NEXRAD 6 or 10 minutes

Trend and Future of Remote Sensing (2)

Globe coverage, high repeatability (or improved temporal resolution)

- AVHRR, 1100m, morning or afternoon

- MODIS, 250-1000m, morning or afternoon

- NPOESS (will be launched in 2009), 370-740m, 4 hours Real-time or near real-time availability

- MODIS available online in the second day ?

- NEXRAD available online in 6 minutes

- NPOESS available online in 15 minutes Cost free or affordable

- Most of the federal collected images are free available or lower

cost, while commercial high resolution images are affordable. Integrated remote sensing and GIS

- Remote sensing applications with the support of GIS

- Remote sensing data as a major GIS data source

Major image processing software

ENVI/IDL: http://www.rsinc.com/ ERDAS Imagine:

http://www.gis.leica-geosystems.com/Products/Imagine/ PCI Geomatics: http://www.pci.on.ca/ ER Mapper: http://www.ermapper.com/ INTEGRAPH: http://imgs.intergraph.com/gimage/ IDRIS: Ecognition:

http://www.definiens-imaging.com/ecognition/pro/40.htm See5 and decision tree

Coarse to moderate spatial resolution data (8km-250m), e.g., NOAA-AVHRR, SPOTVegetation, Terra and Aqua MODIS, Envisat-MERIS, SeaWiFS. These data will provide daily observations and temporally composited products

High spatial resolution data (c. 30m), e.g., SPOT, Landsat-ETM, ASTER, Meteor-3M, EO-1, and IRS high-resolution.

Very high spatial resolution data (<1-4 m), e.g., IKONOS, Quick-Bird. These commercial products will be subject to copyright restrictions.

Multi-view angle optical data, e.g., from Terra-MISR Moderate to high spatial resolution (500m-15m) Synthetic Aperture

Radar data and products, e.g. Envisat-ASAR, ERS-1+2, JERS, Radarsat, SIR-C, SRTM

Very coarse spatial resolution (25km) microwave radiometer data, e.g., Aqua-AMSR-E, DMSP-SSM/I, DMSP-SMMR