[A-CG36] Satellite Earth Environment Observation

[ACG36-15] Comparison of Cloud Properties between SGLI/GCOM-C and MODIS/Terra: Effects of Solar and Satellite Positions

*Pradeep Khatri¹, Hayasaka Tadahiro¹ (1.Center for Atmospheric and Oceanic Studies,Tohoku University)

Keywords:SGLI, Cloud properties, MODIS, comparison

We conducted a comparison of Level 2.0 water and ice cloud properties between the Second-generation Global Imager (SGLI) aboard the GCOM-C satellite and the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra satellite. This comparison encompassed both land and ocean surfaces, aiming to enhance our understanding of the observed cloud properties by SGLI. While differences in retrieval algorithms, ancillary data, surface reflectance, cloud droplet size distribution function, cloud-droplet single scattering properties, etc., play crucial roles in the distinctions between MODIS and SGLI cloud properties, our analyses identified solar and satellite positions as additional dominant factors contributing to differences in the comparison results. We observed that the differences in cloud properties for both water and ice clouds increased with the solar zenith angle (SZA). Similarly, the disparity was more significant for a large difference in satellite viewing zenith angle (VZA) and vice versa. Moreover, we noted significantly smaller (larger) differences in cloud properties when both satellite sensors were in the same (opposite) scattering direction (forward or backward scattering direction). Overall, these findings provide valuable insights for interpreting and implementing satellite-observed cloud properties, further emphasizing the need to incorporate 3D radiative effects in retrieval algorithms. Despite factors influencing the comparison results between MODIS and SGLI, we observed better agreements for water cloud properties than for ice cloud properties and for ocean surfaces compared to land surfaces.