Rs lect 1day_2

Dr.-Ing. Görres Grenzdörffer Remote Sensing

Satellite Remote Sensing 1

Universität Rostock, Professur für Geodäsie und Geoinformatik X 2006

Dr.-Ing. Görres Grenzdörffer

Basics and Applications ofRemote SensingBasics and Applications ofRemote Sensing

Universität Rostock, Professur für Geodäsie und Geoinformatik

Schedule Lectures

• Remote Sensing Basics (1st Day)• Examples of modern airborne and spaceborne remote sensing• The EM-spectrum• Reflectance properties of different objects• Spaceborne sensors

• Satellite Remote Sensing (1st Day)• Landsat, SPOT and ASTER• Highest resolution satellites• SRTM• Change Detection

• Airborne Remote Sensing (2nd Day)• (digital) airborne sensors• Digital orthophotos• Digital oblique imagery

• Digital image Processing (2nd Day)• Pixels and mixels• Spectral bands / low level image operations




Landsat 4/5

StartOrbit heightRepetition rateSensorGround resolutionScene sizeSpectral bands

1982705 km16 DaysTM30*30 m185 * 185 km1 0.45-0.52 µm2 0.52-0.60 µm3 0.63-0.69 µm4 0.76-0.90 µm5 1.55-1.73 µm6 10.4-12.5* µm7 2.08-2.35 µm


1982, 1984705 km16 DaysTM30*30 m185 * 185 km1 0.45-0.52 µm2 0.52-0.60 µm3 0.63-0.69 µm4 0.76-0.90 µm5 1.55-1.73 µm6 10.4-12.5* µm7 2.08-2.35 µm

Inclination: Sun-synchronous, 98.2 degreesEquatorial crossing: Descending node; 10:00am +/- 15 min.Landsat 5 is still operational !


Landsat Coverage History

http://landsat.gsfc.nasa.gov/project/Comparison.html




Landsat 7 - ETM+



1999705 km16 Days

185 * 185 km1 0.45-0.52 µm2 0.52-0.60 µm3 0.63-0.69 µm4 0.76-0.90 µm5 1.55-1.73 µm6 10.4-12.5* µm7 2.08-2.35 µm

705 km16 DaysETM15*15 – 30*30 m185 * 185 km1 0.45-0.52 µm2 0.52-0.60 µm3 0.63-0.69 µm4 0.76-0.90 µm5 1.55-1.73 µm6 10.4-12.5* µm7 2.08-2.35 µm

Landsat 1 – 7 deliver continuous data for more than 30 years now !!Since Mai 2003 Scan line corrector failure


16012,00013,200158

103,0003,300606

4060006,600301-5, 7

MB per Band

Data Lines(rows)

Samples(columns)

Resolution(meters)

BandNumber

Image Dimensions for a Landsat 7 Product

Landsat 7 – ETM Data Specifications




Satellite receiving stations for Landsat TM 4, 5, 7

Mission control of EOSAT Sioux Falls, South Dakota, USAData for Vietnam (Bangkok)


WRS- 2 Path/Row (Landsat 4,5 and 7, and UTM- Zones

http://ltpwww.gsfc.nasa.gov/IAS/handbook/handbook_htmls/chapter5/htmls/wrs_graphic.html

World coverage: 57,784 scenes

127/045




Landsat TM 5 and ETM 7 – Path127/ Row 045

Landsat 5 12/27/1993 Landsat 7 11/04/2000

Hanoi Hanoi


TM and ETM+ Sensor Band Designations

Band Use 1 Blue-green Bathymetric mapping; distinguishes soil from vegetation;

deciduous from coniferous vegetation 2 Green Emphasizes peak vegetation, which is useful for assessing plant vigor 3 Red Emphasizes vegetation slopes 4

Reflected IR Emphasizes biomass content and shorelines

5 Reflected IR Discriminates moisture content of soil and vegetation; penetrates thin clouds

6 Thermal IR Useful for thermal mapping and estimated soil moisture 7 Reflected IR Useful for mapping hydrothermally altered rocks associated with

mineral deposits 8 Panchromatic Landsat 7 carries a panchromatic band (visible through near

infrared) with15 m resolution for “sharpening” of multispectral images

http://landsat.usgs.gov/project_facts/files/landsat_fact_sheet_20023-03.pdf




RGB Band Composite


Pixel color and brightness is determined by the pixel value




Certain bands or band combinations are better than others for identifying specific land cover features

Landsat TM Red= band 3, Green = band 2, Blue = band 1 (True color)

Landsat TM Red= band 4, Green = band 5, Blue = band 3


• Penetrates water better than the other bands so it is often the band of choice for aquatic ecosystems

• Used to monitor sediment in water, mapping coral reefs, and water depth

• The “noisiest” of the Landsatbands since short wavelength blue light is scattered more than the other bands

• Rarely used for "pretty picture" type images

Landsat ETM+ band 1 (0.45- 0.52 µm, blue- green)




• Similar qualities to band 1 but not as noisy.

• Matches the wavelength for the color green.

Landsat ETM+ band 2 (0.52- 0.60 µm, green)


• Since vegetation absorbs nearly all red light (it is sometimes called the chlorophyll absorption band)

• Band 3 can be useful for distinguishing between vegetation and soil and in monitoring vegetation health

Landsat ETM+ band 3 (0.63- 0.69 µm, red)




• Since water absorbs nearly all light at this wavelength water bodies appear very dark. This contrasts with bright reflectance for soil and vegetation so it is a good band for defining the water/land interface

• Sensitive to vegetation cover• Less affected by atmospheric

contamination

Landsat ETM+ band 4 (0.76- 0.90 µm, near infrared)


• Very sensitive to moisture and is therefore used to monitor vegetation water stress and soil moisture.

• Useful to differentiate between clouds and snow

Landsat ETM+ band 5 (1.55- 1.75 µm, mid- infrared)




• Measures surface temperature.

• Geological applications • Differentiate clouds from

bright soils since clouds tend to be very cold

• The resolution is twice as course as the other bands (60 m instead of 30 m)

Landsat ETM+ band 6 (10.40- 12.50 µm, thermal infrared)


• Can detect high surface temperatures

• Also used for vegetation moisture although generally band 5 is generally preferred for that application

• Commonly used in geology

Landsat ETM+ band 7 (2.08- 2.35 µm mid- infrared)




Landsat ETM+ bands 3,2,1 –Penetrates shallow water and shows submerged shelf, water turbidity

Landsat ETM+ bands 4,3,2 –Peak chlorophyll, land/water boundary, urban areas


Landsat ETM+ bands 4,5,3 –Land/water boundary, Vegetation type and condition, soil moisture

Landsat ETM+ bands 7,4,2 –Moisture content in vegetation and soils, geological mapping, vegetation mapping




SPOT 5

•Start May 2002•Weight ca. 3.000 kg•Geometric resolution

• G,R, NIR (10 m), MIR (20m), Pan 5 m (2.5 m)•Sensors (HRV / HRVIR) und swath width

• 1 Sensor: 60 km, 2 Sensors: 117 km• Mirror ± 27° off-nadir-viewing, therefore

variable swath width up to 80 km at 950 km elevation

•Végétation-Instrument: 2250 km•Temporal Resolution

• HRV / HRVIR: 26 days due to off-nadir view of the mirror up 11-times coverage within 26 days possible, for ϕ = 45°)

• Végétation-Instrument: ca. 1 day•Stereo

• Along track (600 * 120 km)• Base to height ration 0.8

SP

OT

Imag

eS

PO

T Im

age


SPOT 5 Imaging modes

SPOT Image




ASTERAdvanced Spaceborne Thermal Emission and Reflection

Radiometer

Flies on Terra platform

Built for METI in Japan

Data processing in Japan and U.S.

Instrument command and control by Japan and U.S.

Joint Science Team

TerraTerra


Terra Launch from VAFB, December 1999




Terra is the flagship of NASA's ESE (Earth Science Enterprise). Terra is the flagship of NASA's ESE (Earth Science Enterprise).

Terra SatelliteTerra Satellite

MODISMODIS

ASTERASTER (TIR)(TIR)ASTERASTER (SWIR)(SWIR)ASTERASTER (VNIR)(VNIR)

MISRMISR

MOPITTMOPITT

CERESCERES

ASTER is the zoom lens of Terra!ASTER is the zoom lens of Terra!


ASTER Instrument Characteristics

60 km swath; <16 day repeat cycle; along track stereo




Visible-NIR Visible-NIR

Short Wave IR Thermal IR


ASTER Response to Indian Ocean TsunamiASTER Response to Indian Ocean Tsunami

Banda Aceh before tsunami (left) and 5 days after tsunami (right)




Eruption of Mt. Etna, Italy

Visible Thermal


• 80 million cubic meter rock/ice avalanche and subsequent debris/mud flows on September 20, 2002

• Overran Karmadon village 18 km down valley

• Over 120 killed• Mudflow continued 15km

further down valley• Rapid ASTER imaging

response over several days following emergency.

• ASTER data used by emergency response teams

Kolka glacier disaster, Sept. 2002




ASTER Application Examples

SO2 plume north of Baghdad from sulfur plant fire. SO2detected by ASTER’s TIR bands

Universität Rostock, Professur für Geodäsie und Geoinformatik www.spotimage.fr




Highest resolution (1m) - Satellites

* Minimum order 64 km²** plus programming fee***Minimum order 100 km², different processing levels

Company/SystemStartOrbit heightRepetition rate (n)Repetition rate (s)ModeGround res. [m]Swath width [km]Stereo capabilitesDelivery - Satellite

ConsumerPrize [$ per km²]

Earth Watch"Quick Bird"15.11.2001470 km4-5 Days< 2 Days

PAN MS0.61 2.416.5 86In Track

15 min. - 48 h.

Orbital Sciences"Orb-View 3"

2002

470 km16 Days< 3 Days

PAN MS1 m 8 m

8kmIn Track

15 min. - 24 h.

Space Imaging“IKONOS"21.9.2000680 km14 Days1 - 3 Days

PAN MS1 m 4 m

11 kmIn Track

24 - 48 h.18 - 150***

Image Sat“EROS-A"05.12.2000480 km4-5 Days< 2 Days

PAN1.8 m12.5

In/cross Track

1.500/Scene**25 - 30*


(GSD 1m - pan)

http://www.spaceimage.com/

Ikonos 1 – 1st picture Washington D.C.



Universität Rostock, Professur für Geodäsie und Geoinformatik IKONOS, Rabat, PAN

Universität Rostock, Professur für Geodäsie und Geoinformatik IKONOS, Singapore, Color



Universität Rostock, Professur für Geodäsie und GeoinformatikQuickbird, Prague before 2003 flood, Color

Universität Rostock, Professur für Geodäsie und Geoinformatik Quickbird, Prague at 2003 flood, Color



Universität Rostock, Professur für Geodäsie und GeoinformatikQuickbird, Vietnam, North of Hanoi,11.03.2007


Highest- Resolution Earth Observation Satellites 2006 - 2012

http://www.asprs.org/news/satellites/asprs_database_090706.pdf




High- Resolution Earth Observation Satellites 2006 - 2012

http://www.asprs.org/news/satellites/asprs_database_090706.pdf


SRTM - DEM generation and analysis

Dr.-Ing. Görres GrenzdörfferChair of Geodesy and Geoinformatics, Rostock University

SRTM SRTM -- DEM DEM generationgeneration and and analysisanalysis




Shuttle Radar Topography Mission (SRTM)

LAUNCH.............: February 11, 2000DURATION.........: 11 daysSPACE SHUTTLE: EndeavourCOMPLETION DATA ANALYSIS: 2004

• X-SAR/SRTM was an innovativeway of collecting highly accurate topographic information using spaceborne radar instruments.

• The collected radar images are converted to digital elevationmodels (DEMs) spanning the globebetween 60° North and 58° South.


Interferometry (1)




Interferometry (2)


Interferometry (3)




http://www.dlr.de/srtm/hintergrund/hintergrund_en.htm

3D with interferometry- Step by step


Accuracy and availability of SRTM- data

Source: http://www.dlr.de/srtm/produkte/produkte.htm

SRTM X-SAR Resolution: 30m / Pixel (DLR)

SRTM C-SAR Freely accessible via Internet : 90m / Pixel (NASA)

±6m 90% vertical errorvertical accuracy (relative)±16m 90% vertical errorvertical accuracy (absolute)±15m 90% circular errorhorizontal accuracy (relative)±20m 90% circular errorhorizontal accuracy (absolute)16-bit Signed IntegerData formatWGS84 or MSL (optionally)Datum (vertical)WGS84Datum (horizontal)1mHeight levels1"x1" Lon& LatRaster size




SRTM- DEM World Coverage

http://www2.jpl.nasa.gov/srtm/world.htm#PIA03394


SRTM- Data example – Shaded relief

20 km

Hanoi




Image drape over SRTM- DEM of Landsat Scene 045/127


Price of satellite data – general

• Dependent upon:

• Urgency- emergency services - the faster you need it, the more you pay

• Age of the data- the more recent the data, the higher its value

• Spatial resolution- the higher the spatial resolution, the higher the cost




Price of satellite data - examples

Price structures of satellite data are generally complicatedSeveral constraints apply for data distribution

Data from several internet sources with subject to change

Satellite GSD / Pixel Price / Scene [€] Price per km² [€]Meteosat II 2.5 km Free* – 500 NOAA - AVHRR 1.1 km Free* – 100Landsat (E)TM 30 m Free* – 1.000 0 - 0.03ASTER 15 – 90 m Free* – 80 0 - 0.02SPOT 4 / 5 2.5 – 20 m 1.000* – 6.000 ** 0.27* – 10 ***

IRS 2.5 – 23 m 1.700* – 4.500 0.35* – 0.90***

IKONOS 1 – 4 m 850* – 24.200 7* – 200 ***

Quickbird 0.6 – 4 m 4.300* –12.200 16* – 45**, ***

* Archived data** Additional fees for programming of the satellite apply*** Minimum order sizes apply


Where do I get satellite data ?

• Through the internet – search and retrieval (via snail mail)

• Google earth ?!?

• Every satellite operating company has an online search and

ordering services

• Satellite distributors (receiving stations) offer satellite data from

many different satellites

• National aerospace agencies offer satellite data from national

(scientific) missions




Wrap Up

• What have we learned?• Where satellite images come from and how they are made • Information content of satellite data• There is an enormous amount of satellite data in different

spectral and spatial resolution around

• After this class• We learn where we will get RS-Data through the internet• Practical exercises with Landsat TM data• Play with the data you have received in the class, using some

of the techniques we discussed

Rs lect 1day_2

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