Onboard ADEOS Research Articles

Atmospheric correction and residual errors in vicarious cross-calibration of AVNIR and OCTS both onboard ADEOS

A method for vicarious calibration of a solar reflectance radiometer through an estimation of reflectance of the test site with a high spatial-resolution radiometer onboard the same platform is proposed. Here we treat the case of the vicarious cross-calibration of ADEOS/OCTS (Advanced Earth Observing Satellite/Ocean Color and Temperature Scanner) with ADEOS/AVNIR (Advanced Visible and Near Infrared Radiometer). Error budget analysis for the proposed method shows that the vicarious calibration error with approximately 4.4% error can be achieved. There the contribution of the high spatial-resolution radiometer error is around 3.3%, while the cross calibration error between the solar reflectance (low resolution) radiometer and the high spatial resolution one is about 2.8%.

An accuracy assessment experiment of the BRDF measured at coarse spatial resolution from space

The accuracy assessment of the Bidirectional Reflectance Distribution Function (BRDF) acquired from satellite sensors at coarse spatial resolution (1 or more km) is not straightforward. One possible strategy is to compare BRDF measurements from spaceborne and airborne sensors on a test area with appropriate characteristics of spatial homogeneity. This Letter describes an experiment based on this principle, aiming at the control of the BRDF measured by POLDER/ADEOS. The BRDF derived from the satellite data is compared with that derived from spatially averaged airborne POLDER data over a forested area of the Landes region. The magnitude and shape of the BRDF measured by both sensors are found to be consistent within an accuracy of 0.01 in reflectance units, except for the principal plane in the blue band where some inconsistency is found. Similar experiments could be used for the verification of other sensors data, such as those of MISR and MODIS onboard Terra, and POLDER 2 onboard ADEOS 2 in the near future.

Prelaunch Calibration of ILAS Onboard ADEOS Spacecraft

Prelaunch Calibration of ILAS Onboard ADEOS Spacecraft