Development of METAL-WRF model for the description of mineral dust processes in the atmosphere based on NASA's EMIT satellite retrievals

Mineral dust stands out as a pivotal climate modulator due to its substantial mass, optical depth, and long-term atmospheric life cycle. It impacts the atmospheric radiative balance, influences cloud dynamics and precipitation patterns, and exerts notable effects on terrestrial and aquatic ecosystems as well as human health. The extent and intensity of these impacts are governed by the mineral composition of dust particles sourced from diverse regions worldwide. METAL-WRF is an advanced numerical framework extending the GOCART-AFWA dust scheme in WRF-Chem 4.4.1 and it is designed to simulate the atmospheric dynamics of dust mineral components, including emission, transport, dry deposition due to gravitational settling, and wet deposition due to the scavenging of dust particles by the hydrometeors. The model accounts for ten mineral types: illite, kaolinite, smectite, calcite, quartz, feldspar, hematite, gypsum, phosphorus, and iron. In the previous version of METAL-WRF the mineralogical composition of dust is derived from the global geological datasets GMINER30 and FERRUM30. A significant improvement in the mapping of dust composition comes from NASA's EMIT sensor that has been operational aboard the International Space Station (ISS) since July 2022. EMIT utilizes advanced imaging spectroscopy to capture light across visible and infrared wavelengths, identifying distinct spectral signatures indicative of surface mineral composition. In this study, we introduce the integration of the first comprehensive EMIT mineralogical dataset in METAL-WRF. The model is used for the simulation of atmospheric dust in HARMONIA 2024 Berlin school. We discuss the comparative distribution of various mineral dust types in the Mediterranean between METAL-WRF simulations incorporating EMIT mineralogy data and earlier versions relying on GMINER30 and FERRUM30 geological databases. The effects of the different mineral types in radiative transfer and ice nuclei activation are examined for specific case studies in comparison with ground based and spaceborne observations.

Acknowledgments. The authors acknowledge financial support from the Hellenic Foundation for Research and Innovation project “Mineralogy of Dust Emissions and Impacts on Environment and Health (MegDeth - HFRI no. 703)” and from the COST Action CA21119, “HARMONIA: International network for harmonization of atmospheric aerosol retrievals from ground-based photometers”.