Evaluation of cloud height, optical thickness, and phase retrievals from the CHROMA algorithm applied to Sentinel-3 OLCI data

Sayer, Andrew M.; Cairns, Brian; Knobelspiesse, Kirk D.; Lelli, Luca; Rajapakshe, Chamara; Giangrande, Scott E.; Thomas, Gareth E.; Zhang, Damao

doi:10.5194/amt-18-6681-2025

Articles | Volume 18, issue 22

https://doi.org/10.5194/amt-18-6681-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/amt-18-6681-2025

© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 18, issue 22

Research article

|

18 Nov 2025

Research article |

| 18 Nov 2025

Evaluation of cloud height, optical thickness, and phase retrievals from the CHROMA algorithm applied to Sentinel-3 OLCI data

Andrew M. Sayer, Brian Cairns, Kirk D. Knobelspiesse, Luca Lelli, Chamara Rajapakshe, Scott E. Giangrande, Gareth E. Thomas, and Damao Zhang

Data sets

Cloud properties global gridded monthly and daily data from 1982 to present derived from satellite observations Copernicus https://doi.org/10.24381/cds.68653055

Short summary

Satellites can estimate cloud height in several ways: two include a thermal technique (colder clouds being higher up), and another looking at colours of light that oxygen in the atmosphere absorbs (darker clouds being lower down). It can also be measured (from ground or space) by radar and lidar. We compare satellite data we developed using the oxygen method with other estimates to help us refine our technique.