Aerosol Intensive Optical Properties in the NMMB-MONARCH

Abstract

The NMMB-MONARCH is a fully online integrated meteorology-chemistry model for short- and mid-term Chemical Weather Forecasts (CWF) developed at the Barcelona Supercomputing Center (Earth Sciences). The meteorological core is the Nonhydrostatic Multiscale Model on the B-grid (NMMB). The global aerosol module includes five natural and anthropogenic species: mineral dust, sea salt, organic matter, black carbon and sulfate. The full online coupling between the aerosol module and the model radiation scheme (RRTMG) has been recently implemented. We present in this work a first evaluation of the aerosol intensive optical properties required by the coupling mechanism: single scattering albedo (ω) and asymmetry factor (g). New aerosol refractive indexes from recent literature have also been tested. We found that the model performance improves when considering a less absorbing mineral dust. Moreover, in anthropogenic areas a purely scattering organic matter and a higher real index for sulfate partially reduce the model systematic biases.