Analysis of the temporal variation of the SYREMIS/GRASP synergetic products

The spatiotemporal evolution of aerosols is highly dynamic, driven by the diurnal motion of boundary layers, meteorological conditions, and transient emissions. Consequently, monitoring these diurnal cycles requires a synergistic approach utilizing multiple satellite platforms to ensure consistent, sub-daily revisit capabilities over target geographical regions. This study investigates the SYREMIS/GRASP approach, which synergistically inverts Level-1 data from LEO+LEO (Sentinel-3/OLCI, Sentinel-5P/TROPOMI) and LEO+GEO (LEO+LEO synergy with Himawari-8/AHI) sensors to resolve aerosol diurnal cycles. By exploiting the expanded information content from combined spectral and multi-angular measurements, we achieve precise high-temporal-resolution retrievals of AOD, Angstrom Exponent, and Single Scattering Albedo. Validation against AERONET and comparison with the XAERDT merged product suite (MODIS+VIIRS+AHI) confirm the method's superior performance. Analysis of 2019 dust and smoke events demonstrates the algorithm’s robustness in monitoring dynamic pollution episodes on regional to global scales.