Dust as Ice-Nuclei: Implications on a Mesoscale Convective Event in the Central Great Plains

Dust is one of the most important ice nuclei (IN) in the atmosphere, yet there is a large amount of uncertainty surrounding the implementation of IN processes in regional and global models. This is a major shortcoming when evaluating the impacts of aerosols on deep convection, as convective invigoration can lead to longer-lasting, larger anvils that may have a significant radiative impact. Additionally, the presence of a larger, more optically thick anvil might affect stability parameters, affecting the storm development via direct effects. Characterizing these effects would reduce the uncertainty of the clouds-aerosol interactions and improve our understanding of mesoscale processes. To determine these effects, we implement the DeMott ice nucleation parameterization into the Morrison microphysics scheme in WRF-Chem v. 3.6 and simulate a mesoscale convective system that occurred on May 27, 2013.  Ensemble sensitivity tests are conducted including (1) ensembles with prescribed dust emissions not including dust as IN, and (2) ensembles with.prescribed dust emissions including dust as IN. Comparisons of the anvil spatial extent, optical thickness, radiative balances, and an evaluation of meteorology will be conducted to determine the effects that including dust as IN might have on the storm system.