![Page 1: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/1.jpg)
MODIS/Meteosat/MISR Surface Albedo Comparison Exercise
MODIS/Meteosat/MISR Surface Albedo Comparison ExerciseB. Pinty (1), M. Taberner (1),
S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5), C. Barker Schaaf (6),
M. M. Verstraete (1), R. E. Dickinson (7), N. Gobron (1), and J-L. Widlowski (1)
(1) Institute for Environment and Sustainability of EC-JRC, Ispra (VA) Italy(2) University of Maryland, College Park, USA
(3) EUMETSAT, Darmstadt, Germany(4) Jet Propulsion Laboratory, Caltech, Pasadena, USA
(5) Makalumedia gmbh, Darmstadt, Germany(6) Boston University, Boston, USA
(7) SEAC, Georgia Institute of Technology, Atlanta, USA
2nd CEOS/WGCV/LPV Workshop on Albedo Products, Vienna, April 27-28, 2005
![Page 2: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/2.jpg)
Various types of Surface albedo (1)Various types of Surface albedo (1)
BHR : Bi-Hemispherical Reflectance is the ratio between the upward and the downward radiant fluxes, that is, accounting for the downwelling diffuse intensities from the sky.
Depends on both surface and ambient atmospheric radiative properties and …the Sun angle.
All quantities can be defined monochromatic or broadband
![Page 3: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/3.jpg)
Various types of Surface albedo (2) Various types of Surface albedo (2)
DHR: Directional Hemispherical Reflectance is the ratio
between the upward flux and the downward collimated flux coming thus from one single direction (Black sky).
Depends on surface radiative properties and …the Sun angle.
All quantities can be defined monochromatic or broadband
BHRiso: If the downwelling diffuse intensities from the sky is assumed fully isotropic then the BHR is equal to the integral of the DHR over all incoming directions (White sky).
Depends on surface radiative properties only.
![Page 4: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/4.jpg)
Surface albedo products from space agencies
Surface albedo products from space agencies
• MODIS delivers DHRs (Black sky) and BHRiso (White sky)
• MISR delivers DHRs and BHRs as flux ratios but under ambient conditions and for the Sun illumination conditions at time of observations
• EUMETSAT delivers DHRs for a fixed Sun angle
and all information needed to reconstruct the DHRs and BHRiso
and all information needed to reconstruct the DHRs at any other Sun angle as well as the BHRiso
to reconstruct the BHRs may require some investments or some level of assumption
The albedo products may also differ wrt the spectral bands of integration they refer to.
![Page 5: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/5.jpg)
Parameterization of the surface-atmosphere radiative coupling
Parameterization of the surface-atmosphere radiative coupling
),;,();,(
);,();,(),;,(
0000
000000
sfcdiff
sfciso
dirsfcsfc
zfzBHR
zfzDHRzBHR
Assuming that the field of downwelling diffuse intensity reaching the surface is PERFECTLY isotropic yields a convenient parameterization for the BLUE SKY ALBEDO
Surface level
Sun angle
Atmospheric optical depth (type of atmosphere)
Surface BRF (amplitude and shape)
ratio of direct to total downward flux
ratio of diffuse to total downward flux
1),;,();,( 0000 sfc
diffdir zfzf with
Pinty et al., JAS, 2005
![Page 6: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/6.jpg)
Surface albedo comparisonSurface albedo comparison
• Perform a comparison between MODIS-Meteosat-MISR surface albedo products : a user perspective.
• Compare similar physical quantities, e,g., BHRs, BHRiso, DHRs.
• Based on year 2001 products: latest public version available.
• For two large geographical regions : Africa-Southern Europe and North-East Europe.
![Page 7: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/7.jpg)
Comparison of Surface BHRiso products from MODIS/Meteosat/MODIS
Comparison of Surface BHRiso products from MODIS/Meteosat/MODIS
• Select the same period of time and identical geographical regions
• Achieve the needed transformations (e.g., BHRs, spectral conversions) to ensure comparison of physical quantities having same meaning
• Identify the product values showing appropriate QA
![Page 8: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/8.jpg)
Albedo comparison for an ‘Ideal’ Band (0.4-1.1μm)
Albedo comparison for an ‘Ideal’ Band (0.4-1.1μm)
![Page 9: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/9.jpg)
Govaerts, pers. Com
![Page 10: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/10.jpg)
![Page 11: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/11.jpg)
Spectral Correction for the Meteosat large band effects
Spectral Correction for the Meteosat large band effects
![Page 12: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/12.jpg)
Spectral conversion to the ‘Ideal’ Band (0.4-1.1μm)
Spectral conversion to the ‘Ideal’ Band (0.4-1.1μm)
Meteosat MISR
![Page 13: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/13.jpg)
![Page 14: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/14.jpg)
January 2001
![Page 15: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/15.jpg)
MISR low & MODIS high
MISR high & MODIS low
![Page 16: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/16.jpg)
January 2001
![Page 17: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/17.jpg)
Histogram of BHRiso differencesHistogram of BHRiso differences
![Page 18: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/18.jpg)
(MISR-MODIS) Albedo
![Page 19: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/19.jpg)
Jun
e 2
00
1
Jan
uary
20
01
Using Shunlin’s conversion factors
Using Yves’s conversion factors
![Page 20: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/20.jpg)
January 2001
![Page 21: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/21.jpg)
Mean BHR values over common area with valid values from one of the two
other sensors
Mean BHR values over common area with valid values from one of the two
other sensors
![Page 22: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/22.jpg)
Ratio of the mean valuesRatio of the mean values
![Page 23: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/23.jpg)
Primary EigenvectorsPrimary Eigenvectors
![Page 24: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/24.jpg)
Correlation between pairs of samplesCorrelation between pairs of samples
![Page 25: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/25.jpg)
Results for year 2001 Shortwave domain
(0.3-3.0 μm)
Results for year 2001 Shortwave domain
(0.3-3.0 μm)
Africa –Southern Europe
![Page 26: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/26.jpg)
Primary EigenvectorsPrimary Eigenvectors
![Page 27: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/27.jpg)
October 2001
![Page 28: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/28.jpg)
Results for year 2001 Visible domain (0.3-0.7 μm)
Results for year 2001 Visible domain (0.3-0.7 μm)
![Page 29: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/29.jpg)
![Page 30: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/30.jpg)
Results for year 2001 Near-infrared domain
(0.7-3.0 μm)
Results for year 2001 Near-infrared domain
(0.7-3.0 μm)
![Page 31: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/31.jpg)
![Page 32: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/32.jpg)
Results for year 2001 Shortwave domain
(0.3-3.0 μm)
Results for year 2001 Shortwave domain
(0.3-3.0 μm)
Northern –Eastern Europe
![Page 33: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/33.jpg)
![Page 34: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/34.jpg)
![Page 35: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/35.jpg)
Full inversion
Magnitude inversion
Backup solution
![Page 36: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/36.jpg)
Mean BHR values over common area with valid values from one of the two
other sensors
Mean BHR values over common area with valid values from one of the two
other sensors
Full inversion
![Page 37: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/37.jpg)
![Page 38: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/38.jpg)
![Page 39: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/39.jpg)
Primary EigenvectorsPrimary Eigenvectors
Full inversion
![Page 40: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/40.jpg)
Northern –Eastern Europe
Hexadecad 6: End of March 2001
![Page 41: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/41.jpg)
![Page 42: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/42.jpg)
![Page 43: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/43.jpg)
Issues and caveatsIssues and caveats
• An error was recently identified in the MISR processing code: BHRs tend to be biased high by about 2 to 3% on average (season & latitude dependent).
• The nominal spectral conversion formulae (from Liang and Govaerts) agree well.
• MODIS BHRs are off when estimated from the backup algorithm.
![Page 44: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/44.jpg)
Africa –Southern Europe
![Page 45: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/45.jpg)
Magnitude inversion
January 2001
June 2001
![Page 46: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/46.jpg)
Northern –Eastern Europe
![Page 47: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/47.jpg)
Magnitude inversion
January 2001
June 2001
![Page 48: MODIS/Meteosat/MISR Surface Albedo Comparison Exercise B. Pinty (1), M. Taberner (1), S. Liang (2), Y. Govaerts (3), J.V. Martonchik (4), Lattanzio (5),](https://reader036.vdocuments.mx/reader036/viewer/2022070412/5697bf871a28abf838c88a55/html5/thumbnails/48.jpg)
Conclusions and PerspectivesConclusions and Perspectives
• Albedo (BHRiso) comparison reveals very good agreement between MODIS-MISR-Meteosat (high QA) products.
• Extend the comparison exercise globally.
• Repeat the exercise for DHRs.