ACIX is an international collaborative initiative to inter-compare a set of atmospheric correction (AC) processors for high-spatial resolution optical sensors. The exercise will focus on Landsat-8 and Sentinel-2 imagery over a set of test areas. The inter-comparison of the derived Bottom-of-Atmosphere (BOA) products is expected to contribute to the understanding of the different uncertainty contributors and help in improving the AC processors.
The free and open data access policy to Landsat-8 and Sentinel-2 satellite imagery has stimulated the development of atmospheric correction (AC) processors for generating Bottom-of-Atmosphere (BOA) products. Several entities have started to generate (or plan to generate in the short term) BOA reflectance products at global scale for Landsat-8 and Sentinel-2 missions. To this end, NASA and the European Space Agency are organizing this exercise on AC processors inter-comparison. The results of the exercise are expected to point out the strengths and weaknesses, as well as communalities and discrepancies of various AC processors, in order to suggest and define ways for their further improvement.
Objectives and Expected Outcomes
The exercise aims to bring together the developers of the available AC processors, who are invited to generate the corresponding BOA products. The input data will be Landsat-8 and Sentinel-2 imagery of various test sites, i.e. coastal, agricultural, snow/artic areas and deserts. A common and harmonised inter-comparison procedure will be agreed and followed by all the participants.
Schedule and Deadline
The Atmospheric Correction Inter-comparison Exercise will be performed in three phases: