Multi-scale Simulations of Atmospheric Pollutants Using a Non-hydrostatic Icosahedral Atmospheric Model

Abstract

We have developed a seamless global-to-regional model to calculate atmospheric aerosol chemistry by coupling existing aerosol and chemical modules to a global cloud-system-resolving model (NICAM-Chem). The model can simulate air pollutants with various grid sizes ranging from global low resolution (~200 km) on yearly scales to regional high resolution (~10 km) on monthly scales and global high resolution (<10 km) on weekly scales. To date, we have confirmed that the NICAM-Chem simulated aerosols at low-to-high resolutions, and global-to-regional scales are generally comparable to validated observations. Furthermore, the very recent availability of cutting-edge computational capabilities provided by the K computer at RIKEN in Japan enabled us to perform seasonal air pollution simulations with a high global resolution model (14 km), which generally reproduced the observed aerosol distributions. In this paper, we introduce the following application studies using the NICAM-Chem model: future scenario experiments, downscaling using results obtained by a coupled atmosphere-ocean model, estimation of human health due to PM2.5, simulations of radioactive matter using a regional model, and aerosol assimilation by a localized ensemble transform Kalman filter.