Miguel Pino Carmona, University of Granada, Spain

Dust outbreaks are a source of increasing concern in regions nearby arid deserts, such as the Iberian Peninsula, which suffers several Saharan dust intrusion events every year. Mineral dust, as other aerosols, affects weather on various key aspects, being an important player in the radiation budget as well as in the cloud formation and precipitation processes. In addition, high rates of aerosol concentrations may have an important impact on human health, especially over that non-negligible fraction of the population that suffer from respiratory or cardiovascular issues.

The Weather Research and Forecasting (WRF) numerical weather model coupled with chemistry (WRF-Chem) includes physical parameterizations that allow simulating the whole dust aerosol budget in the atmosphere, from its emission in remote sources, to the transport and interaction with atmospheric constituents and radiation fluxes at emission locations. However, WRF-Chem allows multiple physical configurations to that aim, each one producing different results. In addition, some aspects of such configurations might benefit from a fine-tuning to specific applications and locations. All these possible combinations require of a thorough analysis.

This work presents the study of a strong dust outbreak episode in the southern Iberian Peninsula on July 22nd-26th, 2021, using WRF-Chem and ground-based reference observations of aerosols from two AERONET stations at different altitudes. The study inter-compares three different model configurations alternatively based on the GOCART, MOSAIC and MADE WRF aerosol schemes. All use a similar dust emission scheme, which is first calibrated here to match the aerosol loading observed at the AERONET sites. Afterwards, the optical properties simulated by WRF in each case, particularly the integrated aerosol optical depth and the back-scattering profiles, are compared against those observed at the ground sites. Subsequent stages of the study will pursue the simulation of aerosol-cloud interactions.