Simulated aerosol key optical properties over global scale using an aerosol transport model coupled with a new type of dynamic core

- We simulate aerosol key optical properties using a new aerosol transport model.
- The correlations between model and AERONET are strong for both AOD and AE.
- 82.1% of the simulated AODs agree within a factor of two with the measurements.
- Model underestimates both the global 3-year mean AOD and AE.

Aerosol optical depth (AOD), Ångström Exponent (AE), and single scattering albedo (SSA) simulated by a new aerosol-coupled version of Nonhydrostatic ICosahedral Atmospheric Model (NICAM) have been compared with corresponding AERONET retrievals over a total of 196 sites during the 2006-2008 period. The temporal and spatial distributions of the modeled AODs and AEs match those of the AERONET retrievals reasonably well. For the 3-year mean AODs and AEs for all sites show the correlations between model and AERONET of 0.753 and 0.735, respectively, and 82.1% of the modeled AODs agree within a factor of two with the retrieved AODs. The primary model deficiency is an underestimation of fine mode aerosol AOD and a corresponding underestimation of AE over pollution region. Compared to the retrievals, the model underestimates the global 3-year mean AOD and AE by 0.022 (10.5%) and 0.329 (31.2%), respectively. The probability distribution function (PDF) of the modeled AODs is comparable to that of the retrieved ones, however, the model overestimates the occurrence frequencies of small AEs and SSAs.