الصور الفضائية والاقمار الصناعية pdf - د.علاء حمدون

Remote Sensing

“the art, science, and technology of obtaining

reliable information about physical objects and the

reliable information about physical objects and the
environment, through the process of recording,

environment, through the process of recording,
measuring and interpreting imagery and digital

measuring and interpreting imagery and digital

measuring and interpreting imagery and digital
representations of energy patterns derived from

representations of energy patterns derived from
noncontact sensor systems”. (Cowell 1997)

noncontact sensor systems”. (Cowell 1997)

Taken from: Introductory Digital Image Processing. 3

edition.

Jensen, 2004

Remote Sensing

A remote sensing instrument

collects information about an

object or phenomenon within the

instantaneous-field-of-view

(IFOV) of the sensor system

without being in direct physical

contact with it. The sensor is

located on a suborbital

or satellite platform.

Introductory Digital Image Processing. 3rd edition. Jensen, 2004

Sensors

Passive

Sun’s energy which is reflected

Sun’s energy which is reflected
(visible) or

(visible) or
Absorbed and re

Absorbed and re--emitted as

emitted as

thermal infrared wavelengths

thermal infrared wavelengths
ASTER, Landsat, AVHRR

ASTER, Landsat, AVHRR

Active

Emit radiation

Emit radiation
Radiation reflected is detected and

Radiation reflected is detected and
measured

measured
LIDAR, RADAR, and SONAR

LIDAR, RADAR, and SONAR

http://ccrs.nrcan.gc.ca/resource/tutor/fundam/chapter1/06_e.php

Spectral Resolution

Introductory Digital Image Processing. 3rd edition. Jensen, 2004

Spatial

Spatial Resolution

Resolution

Introductory Digital Image Processing. 3rd edition. Jensen, 2004

MODIS

Moderate Resolution Imaging

Moderate Resolution Imaging
Spectroradiometer

Spectroradiometer
Launched in 1999 on NASA’s Earth

Launched in 1999 on NASA’s Earth
Orbiting System (EOS) platform

Orbiting System (EOS) platform

Orbiting System (EOS) platform
36 spectral bands

36 spectral bands

http://terra.nasa.gov/About/MODIS/modis_

http://terra.nasa.gov/About/MODIS/modis_
swath.html

swath.html

MODVOLC

Algorithm created by University of Hawaii

Algorithm created by University of Hawaii
“The MODVOLC algorithm automatically

“The MODVOLC algorithm automatically
scans each 1 kilometer pixel within it to

scans each 1 kilometer pixel within it to
check for the presence of high

check for the presence of high--

check for the presence of high

check for the presence of high--
temperature hot

temperature hot--spots.”

spots.”

Used not only for volcanic eruptions, but

Used not only for volcanic eruptions, but
wildfires as well.

wildfires as well.

http://modis.higp.hawaii.edu/

Mount Belinda

South Sandwich Islands

Eruption first recorded

Eruption first recorded
using MODVOLC

using MODVOLC

Used MODIS, Landsat

Used MODIS, Landsat
7ETM+, ASTER, and

7ETM+, ASTER, and
RADARSAT

RADARSAT--1

Identified first recorded

Identified first recorded
eruption ever

eruption ever

http://www.intute.ac.uk/sciences/worldguide/satellite/2374.jpg

Selected high spatial-resolution images of Montagu Island. North is up. A) Landsat 7 ETM+ Band 8 image from 4 Jan
2002 showing diffuse plume (P) emanating from Mount Belinda s summit (MB) and tephra deposits on north flank.
Scale bar applies to A, B and C. B) ASTER visible band composite image (Bands 3–2-1) on 7 Dec 2003, showing
tephra deposits and 2003 lava flow (L2). C) RADARSAT-1 image from 30 Oct 2003 showing recent morphology, with
inset (D). Arrows point to approximate summit of Mount Belinda and vent location (MB), ash plumes (P), 600 m long
lava flow first observed in Jan 2002 (L1), entrenched 2 km long lava flow first observed in Aug 2003 (L2), and arcuate
fractures unrelated to this eruption (F). RADARSAT image was provided by the Alaska Satellite Facility, and is
copyright 2003 CSA

ASTER

Advanced Spaceborne Thermal Emission

Advanced Spaceborne Thermal Emission
and Reflection Radiometer

and Reflection Radiometer
Launched in 1999, part of NASA’s EOS

Launched in 1999, part of NASA’s EOS
Spatial Resolution 15m(VNIR),

Spatial Resolution 15m(VNIR),

Spatial Resolution 15m(VNIR),
30m(SWIR), 90(TIR). 16 day temporal

30m(SWIR), 90(TIR). 16 day temporal
resolution possible

resolution possible
Per request basis

Per request basis

ASTER Uses

Volcanological Studies

Volcanological Studies
Mineralogical Studies

Mineralogical Studies
Hydrothermal Studies

Hydrothermal Studies
Forest Fires

Forest Fires

Forest Fires
Glacier Studies

Glacier Studies
Limnological Studies

Limnological Studies
Climatology Studies

Climatology Studies
Digital Elevation Models

Digital Elevation Models
http://asterweb.jpl.nasa.gov/gallerymap.asp

http://asterweb.jpl.nasa.gov/gallerymap.asp

http://asterweb.jpl.nasa.gov/content/03_data/05_Application_Examples/volcanology/default.htm

North Shore

Oahu, HI

15 x 15 m

(RGB= 1,4,3)

ASTER

LANDSAT

Launched in 1972,

Launched in 1972,
Managed by NASA and

Managed by NASA and
USGS

USGS

ETM 7+ has 7 bands (30

ETM 7+ has 7 bands (30
and 60 m) and a

and 60 m) and a

and 60 m) and a
panchromatic (15)

panchromatic (15)

Collected every 16 days

Mapping lava flows,

Mapping lava flows,
thermal monitoring,

thermal monitoring,
extrusion rates

extrusion rates

Introductory Digital Image Processing. 3rd edition. Jensen, 2004

Landsat 7 Image of

Palm Spring, CA

30 x 30 m

(bands 4,3,2 = RGB)

AVHRR

Advanced Very High Resolution

Advanced Very High Resolution
Radiometer

Radiometer
First launched in 1978 by NOAA

First launched in 1978 by NOAA
Global coverage 4.4 km, U.S 1 km (low

Global coverage 4.4 km, U.S 1 km (low

Global coverage 4.4 km, U.S 1 km (low
spatial resolution

spatial resolution
Collected twice a day (High temporal

Collected twice a day (High temporal
resolution)

resolution)

http://www.geo.mtu.edu/volcanoes/research/avhrr/images/spurr/

IKONOS

Panchromatic Images

of Washington, DC

Jensen, 2004

1 x 1 m spatial resolution

First satellite launched by a private company, launched in 1999

1 meter panchromatic, 4 m visible and near infrared

Active Sensors

Emits energy pulse, measure backscatter,

Emits energy pulse, measure backscatter,
records as a digital number

records as a digital number

Long wavelength

Long wavelength--microwave

microwave

Long wavelength

Long wavelength--microwave

microwave

Penetrates clouds and vegetation

RADAR always black and white with speckled

RADAR always black and white with speckled
texture

texture

RADAR

http://www.jpl.nasa.gov/images/earth/california/sar-la-browse.jpg

European Remote Sensing 1 satellite radar image of stormwater runoff plumes from Los
Angeles and San Gabriel Rivers into the Los Angeles and Long Beach Harbors. Dec. 28,
1992. Image credit: ESA

LIDAR

Light Detection and Ranging

Light Detection and Ranging
Transmits a laser light to target

Transmits a laser light to target
15 cm accuracy

15 cm accuracy
http://vulcan.wr.usgs.gov/Volcanoes/MSH/

http://vulcan.wr.usgs.gov/Volcanoes/MSH/
Eruption04/LIDAR/

Eruption04/LIDAR/