Validation of global land-ocean aerosol products retrieved from the DPC-2/GF-5(02) on-orbit measurements

Abstract. The Chinese second-generation Directional Polarization Camera (DPC-2) onboard the GF-5(02) satellite provides global multi-angle, multispectral polarization observations, effectively bridging the gap between POLDER/PARASOL and SPEXone/PACE. Using one year of DPC-2/GF-5(02) measurements, land-ocean aerosol products are generated by fully exploiting polarization and angular information to enhance sensitivity to aerosol properties. Ground-based observations from the AErosol RObotic NETwork (AERONET) are used to evaluate the retrieval accuracy of Aerosol Optical Depth at 550 nm (AOD₅₅₀), Ångström Exponent between 440 nm and 670 nm (AE_440-670), and Single Scattering Albedo at 440 nm (SSA₄₄₀), demonstrating the stability and reliability of the retrievals. For AOD₅₅₀, the Root Mean Square Error (RMSE) and bias are 0.109 and −0.006 over land, and 0.071 and −0.001 over ocean. For AE_440-670, the RMSE and bias are 0.488 and −0.151 over land, and 0.275 and −0.047 over ocean. For SSA₄₄₀, the RMSE and bias are 0.044 and 0.003 over land, and 0.039 and 0.002 over ocean. Comparisons with mainstream satellite aerosol products indicate comparable and consistent accuracy. Overall, these results provide a coherent global characterization of aerosol distribution and properties, highlighting the strong potential of DPC-2/GF-5(02) for long-term aerosol monitoring and climate research.