Abstract
The NASA CERES EBAF product provides the scientific community observed TOA fluxes to monitor the Earth’s energy imbalance and for climate model validation. To provide MODIS and VIIRS cloud retrieval continuity, the CERES project inter-calibrates MODIS and VIIRS by ray-matching coincident Earth-view measurements from analogous channels over all-sky tropical ocean. SNOs are not possible between NPP, NOAA satellites and follow on JPSS satellites, which will fly in the same 1:30 PM orbit but are not flown in tandem. The CERES project will utilize the Libya-4 and Dome-C invariant targets as well as other approaches to radiometrically scale between MODIS and VIIRS reflective solar bands.
The improved characterization of Libya-4 and Dome-C will not only account for BRDF effects but also consider ozone, precipitable water, and other atmospheric parameters as inputs into modeling. Correlating precipitable water with Libya-4 TOA reflectance reduced the temporal variability by half for select channels. Improvements in identifying pristine clearsky events are based on multiple channels and atmospheric parameters as well. Several spectral band adjustment factors based on hyper-spectral datasets, which are used to account for spectral band differences, are analyzed and validated using spectrally disparate VIIRS M and I channel comparisons. Consistent Libya-4 and Dome-C radiometric scaling factors validates the methodology.
Improved Characterization of Libya-4 and Dome-C for Consistent Radiometric Scaling Between VIIRS Sensors
The NASA CERES EBAF product provides the scientific community observed TOA fluxes to monitor the Earth’s energy imbalance and for climate model validation. To provide MODIS and VIIRS cloud retrieval continuity, the CERES project inter-calibrates MODIS and VIIRS by ray-matching coincident Earth-view measurements from analogous channels over all-sky tropical ocean. SNOs are not possible between NPP, NOAA satellites and follow on JPSS satellites, which will fly in the same 1:30 PM orbit but are not flown in tandem. The CERES project will utilize the Libya-4 and Dome-C invariant targets as well as other approaches to radiometrically scale between MODIS and VIIRS reflective solar bands.
The improved characterization of Libya-4 and Dome-C will not only account for BRDF effects but also consider ozone, precipitable water, and other atmospheric parameters as inputs into modeling. Correlating precipitable water with Libya-4 TOA reflectance reduced the temporal variability by half for select channels. Improvements in identifying pristine clearsky events are based on multiple channels and atmospheric parameters as well. Several spectral band adjustment factors based on hyper-spectral datasets, which are used to account for spectral band differences, are analyzed and validated using spectrally disparate VIIRS M and I channel comparisons. Consistent Libya-4 and Dome-C radiometric scaling factors validates the methodology.