Evaluation of Aerosol Properties Observed by DSCOVR/ EPIC Instrument From the Earth-Sun Lagrange 1 Orbit

Frequent observations of aerosols from space are essential for studying aerosol effects on climate and air quality applications. We present results of aerosol properties derived from observations made by the Earth Polychromatic Imaging Camera (EPIC) sensor onboard the Deep Space Climate Observatory satellite. EPIC's near-hourly measured radiances at 340 and 388 nm from sun rise to sunset have been used as input to the EPIC near-UV aerosol algorithm (EPICAERUV) for retrieving aerosol extinction optical depth (AOD), single scattering albedo (SSA), above-cloud aerosol optical depth (ACAOD), and ultraviolet Aerosol Index. Comparisons of AERONET and EPIC daily mean AOD values at eight selected representative sites yield correlation coefficients in the range from 0.68 to 0.89 and root mean square errors from 0.10 to 0.31. A similar comparison of EPIC-retrieved SSA against the AERONET inverted SSA product revealed nearly 51% (76%) of matchups in agreement within ±0.03 (±0.05). Furthermore, the retrievals of ACAOD are also found to compare reasonably well, with 50%–70% of matchups falling within expected uncertainty against the direct airborne measurements acquired during the ObseRvations of Aerosols above CLouds and their intEractionS campaign. Using the EPICAERUV aerosol product, we analyzed the spatial and temporal patterns of specific smoke events caused by wildfires over North America over the last four years.