Earthdata Forum

Dear Ocean Color Teams:

I am interested in using the MODIS-Aqua FLH data and PACE-OCI FLH data, and I find that, compared to MODIS FLH, PACE FLH is lower (2025.03 FLH product). I would like to know that whether the PACE FLH algotithm is as same as MODIS FLH algorithm? Also, the sensors of the OCI are highly advanced, and are there any validations of the PACE-OCI FLH product currently? Thanks very much for your assistant!

I'm looking forward to your reply.
Yours sincerely,
Tian

Hello Tian,

Apologies for the delayed response. Compared to MODIS, the PACE OCI nFLH algorithm uses additional bands — specifically nLw(650, 660, 710, and 720), versus nLw(667 and 748) for MODIS. The ATBD and corresponding validation are still under development, so we appreciate your patience as we work toward publishing them.

Guoqing

Thank you very much!It will help us a lot. Thanks!

Fundamentally, the current FLH algorithm is the same for MODIS and OCI. OCI just has more bands for deriving the baseline from which the line height is computed. A more sophisticated approach that takes advantage of the high spectral sampling of OCI in the chlorophyll a fluorescence region is planned.

Regards,
Sean