MAIAC Aerosol Retrieval and Hyperspectral Atmospheric Correction of TROPOMI Data

Hyperspectral surface reflectance is an essential component in retrieving atmospheric composition (e.g., aerosol and trace-gases) and is used for numerous applications, for instance, forest management, land cover and land cover change analysis, and modeling of terrestrial carbon. One of goals of this work is to retrieve hyperspectral surface reflectance (SR) from ultraviolet-visible-near infrared (UV-VIS-NIR) (340-495nm; 675-775nm; 5nm resolution) globally over land from TROPOspheric Monitoring Instrument (TROPOMI) onboard Sentinel-5 Precursor satellite. We adapted the NASA Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm to retrieve aerosol optical depth and spectral absorption, aerosol speciation (black carbon/brown carbon for smoke, hematite/goethite for dust), and perform hyperspectral atmospheric correction of TROPOMI data. We will describe MAIAC TROPOMI algorithm and products, discuss aerosol validation against AERONET, and give examples of hyperspectral SR with seasonal and regional variations over representative sites. The hyperspectral surface reflectance over vegetated temperate regions shows expected well-behaved spectra from blue to NIR with well-expressed seasonality of green-up and senescence. This work prototypes MAIAC algorithm for processing of the hyperspectral Ocean Color Instrument (OCI) onboard future NASA PACE mission.