MODIS is a scanning radiometer with a two-sided primary mirror. Currently, there are two instruments on-orbit: on the Terra and on the Aqua satellite. The calibration of the instruments is rather complex, due to the need to model a time dependent scan angle dependency. At the moment, there are four main calibration methodologies employed to derive calibration coefficients for the processing of MODIS Aqua ocean color products:
Calibration Information on MODIS
- Solar diffuser calibrations (Xiong et al., 2010)
- Lunar calibrations (Sun et al., 2007)
- Desert targets (Sun et al., 2014)
- Cross calibration to MODIS Aqua Level 3 products (Meister et al., 2012)
- Vicarious calibration (Franz et al., 2007)
The latest coefficients derived with the above methods are distributed as part of the SeaDAS package.
The MODIS on Terra is (almost) identical in design to MODIS Aqua, but the radiometric quality of its ocean color bands is significantly worse. The polarization sensitivity of the short wavelength bands is changing as a function of time, see Kwiatkowska et al., 2008. Therefore, the radiometric calibration and polarization sensitivity coefficients of the ocean color bands for the processing of MODIS Terra ocean color products are cross-calibrated to MODIS Aqua. This means that the temporal trends of the MODIS Terra ocean color products are expected to follow those of MODIS Aqua. Therefore, if possible, it is preferable to use MODIS Aqua ocean color products rather than MODIS Terra ocean color products.
The references below describe the calibration methods applied for MODIS. The Meister et al. paper also describes how the results from each method are combined.
- Franz et al., 2007, Sensor-Independent Approach to the Vicarious Calibration of Satellite Ocean Color Radiometry, Applied Optics, Vol. 46, No. 22, pp. 5068-5082.
- Kwiatkowska et al., 2008, Crosscalibration of Ocean-Color Bands from Moderate-Resolution Imaging Spectrometer on Terra Platform, Applied Optics, Vol. 47, No. 36, pp. 6796-6810.
- Meister et al., 2012, Corrections to the Calibration of MODIS Aqua Ocean Color Bands, IEEE Transactions on Geoscience and Remote Sensing, Vol. 50, No. 1, pp. 310-319.
- Sun et al., 2007, MODIS Reflective Solar Bands On-Orbit Lunar Calibration, IEEE Transactions on Geoscience and Remote Sensing, Vol. 45, No. 7, pp. 2383-2393.
- Sun et al., 2014, Time-Dependent Response Versus Scan Angle for MODIS Reflective Solar Bands, IEEE Transactions on Geoscience and Remote Sensing, Vol. 52, No. 6, pp. 3159-3174.
- Xiong et al., 2010, On-orbit calibration and Performance of Aqua MODIS Reflective Solar Bands, IEEE Transactions on Geoscience and Remote Sensing, Vol. 48, No. 1, pp. 535-546.
Below are links to selected studies of specific issues related to MODIS calibration.
- Master index of OBPG MODIS L1b LUTs
- Comparison of recent m1 to operational LUT
- Striping case study for MODIS Aqua (April 2010)
- Master index of OBPG MODIS Aqua XCAL runs (post January 2010)
- Partial index of OBPG MODIS Aqua tests (AT or AV, post January 2011, calibration related only)
- Analyses of Aqua m1 (pre-2007)
- Prelaunch Polarization for Aqua (pre-2007)
- Prelaunch RVS for Aqua and Terra (pre-2007)
- RSR for Aqua (pre-2007)
- MCST publications (pre-2007)
- Angstroems L3 images (June 2007)
- Along-track Striping in MODIS bands 1-4 (July 2007)
- MODIS Hi- and Low-gain bands13 and 14 (October 2007)
- MODIS Aqua time dependent NIR RVS (November 2007)
- Calculation of MODIS polarization parameters Q and U (July 2008)
- Powerpoint presentations
- Correlation of ocean color products and cirrus reflectance (November 2008)
- Application of cross-calibration results in MCST LUT to MODIS Aqua band 8 (July 2009)
- MODIS Aqua ocean band calibration relative to land bands (November 2009)
- New polarization correction for MODIS Aqua (new best detector selection) (December 2009)
For further information, please contact:
Ocean Biology Processing Group, NASA/GSFC Code 614.2
Building 28, Room W119, Greenbelt, MD 20771 USA
Tel #: (301) 286 - 0758, FAX #: (301) 286 - 0268