Cloud modelling at grey-zone resolutions
Clouds are the result of processes happening at multiple scales. In our community’s quest to gain a comprehensive understanding of cloud processes, multiple-nested grids, including high-resolution grids, are now commonly employed to model them. However, changes in grid spacing impact the physics that can be captured by a model. For instance, the vertical fluxes of heat, moisture, and momentum are sensitive to model resolution. In this paper, we explored how model representation of cloud processes changed with model resolution for a case of low-level roll clouds that were observed at Utqiaġvik, Alaska. This work was necessary because many global and regional models are moving toward cloud-resolving scales, also known as grey zone and sub-kilometer scales. Our study focused on the transition of cloud characteristics and the related boundary layer environment with spatial resolution, ranging from the mesoscale and grey zone to the near large-eddy scales.