Presentazione di PowerPoint

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CHRIS / PROBA OVER SAN ROSSORE (Pisa, Italy)
FORESTRY TEST SITE
Ivan Pippi CONSIGLIO NAZIONALE DELLE
RICERCHE Istituto di Fisica Applicata Nello
Carrara Firenze - ITALIA
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CHRIS-PROBA AO PROPOSAL Assimilation of
biophysical and biochemical variables in
biochemical and hydrological models at landscape
scale
PRINCIPAL INVESTIGATOR Dr. Massimo Menenti CNR -
ISAFoM Napoli - ITALIA
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TOPICS

• Preliminary verifications
• Data quality assessment
• Geometric corrections
• Atmospheric corrections
• BRDF / Albedo modeling
• San Rossore test site
• In-situ data acquisition

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Preliminary verifications
Track of PROBA 1 over Italy on 19 June 2002
Look Angles Ephemeris To PROBA 1 - Sat 26958
(06/19/02) From San Rossore ITALY ( 10.300 E
/ 43.730 N / 20 M)
NORAD Two-Line Elements (TLE) related to 31 May
2002 PROBA 1 1 26958U 01049B
02151.16044139 .00001906 00000-0 20796-3 0
7813 2 26958 97.8788 227.4454 0085831 228.1964
131.1902 14.86502563 32815
Resuts of SatSpy 4.0 Results of CNR-IFAC
SatelTack
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Acquisition geometry
Satellite
Sun
FZA
MZA
MZA Minimum Zenith Angle FZA Fly-by Zenith Angle
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Acquisition geometry
Risults
MZA Minimum Zenith Angle FZA Fly-by Zenith Angle
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San Rossore over-flight CHRIS band configuration
MODE 4 - Clorophyll
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San Rossore over-flight CHRIS band configuration
MODE 4 - Clorophyll
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Response Corrected Images (Level 1B)
San Rossore (Pisa,Italy) location Latitude
43o44N - Longitude 10o 18E Acquisition time
19 June 2002 - 1029 UTC Satellite altitude 565
km MZA -8o
FZA 36o
FZA -36o
FZA 55o
FZA 0o
FZA -55o
Full swath width - 744 x 400 pixel in µW m-2 sr-1
nm-1 - False color RGB C13-C4-C2
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Data quality assessment
Some statistical results for the image
CHRIS_020619_2F80_03. Dynamic range reduction 10
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Pine tree spectra band position verification
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Geometric corrections
CHRIS_020619_2F80_03 image l552 nm, MZA -8o
FZA0o, 766 x 400 pixel
Geometrically corrected image 816 x 400 pixel
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Geometric corrections
CHRIS_020619_2F83_03 image l552 nm, MZA -8o
FZA55o, 766 x 400 pixel
Geometrically corrected image 1379 x 400 pixel
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Atmospheric corrections
The starting model
Optically thin atmosphere
X
Lambertian surface
where
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Atmospheric corrections
In the visible and near infrared range
then for CHRIS level 1B data
where ?(?) ground reflectance, E(?) ground
solar irradiance, T (?, ?) atmospheric
transmittance, Ls(?) at sensor radiance, Lu (?,
?) up-welling radiance and Ld (?, ?)
down-welling radiance.
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Atmospheric corrections
Modtran 4 components
PLOTS OF OUTPUT FILE .7sc
sensor
Sun
SOL SCAT
GRND RFLT
DRCT RFLT
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Atmospheric corrections
Results
At-sensor spectral radiance for various pixels of
the image CHRIS_020619_2F80_03
Hemispherical spectral reflectance for the same
pixels of the corrected image applying the
described model
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BRDF / Albedo
A new physical approach
The reflectance spectra have been retrieved
considering the observed surface as Lambertian
diffuser. To improve the physical model, we have
to take into account the Bi-directional
Reflectance Distribution Function (BRDF). The
BRDF is defined as the ratio of the radiance
leaving a sample to the irradiance impinging
that sample, for a given direction of incidence
and direction of view. The incidence direction
and the viewing direction are specified by four
angles the incident zenithal and azimuth angles.
The radiance emerging from a Lambertian surface
can be expressed as
If we assume that the observed target doesnt
anymore behave as a perfectly diffuser, the
at-surface radiance can be expressed as
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BRDF / Albedo
A new physical approach
In its simplest form, the BRDF is thought as a
separable function
where
From the obtained equations we can define a new
function as the at-surface radiance normalized to
the impinging solar irradiance
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The San Rossore experimental site
Image acquired at 18m of spatial resolution by
MOMS-2P on board of the module Priroda of the MIR
space station (15/3/97)
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The San Rossore experimental site
Principal investigators Guenther Seufert, JRC -
IES, Ispra Giorgio Matteucci, JRC - IES,
Ispra Federico Magnani, DCA, Universita di
Bologna Marco Borghetti, DPV, Universita della
Basilicata, Potenza Sabrina Raddi, DISTAF,
Universita di Firenze Fabio Maselli, CNR -
IBIMET, Firenze Massimo Menenti, CNR - ISAFoM,
Napoli Ivan Pippi, CNR - IFAC, Firenze
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In-situ measurements

• Temperature
• Pressure
• Umidity
• Wind speed and direction
• Integrated solar irradiance (0,28 - 2,8 µm , 3,5
  - 50 µm)
• Spectral solar irradiance (0,35 - 0,95 µm)
• - LIDAR measurements
• - Surface reflectance

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Airborne Imaging Spectrometers
Casa 212
MIVIS
VIRS-200
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MIVIS
Multispectral Infrared and Visible Imaging
Spectrometer
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VIRS-200
Airborne Imaging Spectrometer