Size-resolved and Chemically resolved Aerosol-Chemical Transport Model of the Global Troposphere

Model-based estimates of aerosol distributions are required to understand how tropospheric aerosols affect the radiative forcing of Earth's climate. In this work we present a new three-dimensional chemical transport model coupled with a size and chemically resolved model of atmospheric aerosols, a detailed study of the effect on gas-phase species due to aerosol addition is investigated. The Intermediate Model of Global Evolution of Species (IMAGES) serves as the host gas-phase atmospheric chemical transport model for the particle-phase thermodynamics aerosol model, computed by the Simulating Composition of Atmospheric Particles at Equilibrium 2 (SCAPE2). The global distributions, budgets, and trends of 53 gas-phase species and 19 aerosol-phase species are followed over a grid with 5° in longitude and 5° in latitude horizontal resolution, and 25 vertical sigma layers. The model accounts for surface emissions, chemical transformations, dry deposition, wet deposition, condensation/evaporation, and nucleation processes.