Simulation of turbulence in the atmospheric boundary layer (ABL) is made difficult by the large range of scales present in the turbulent motions. To manage such simulations, a model needs to use efficient numerical methods, flexible to handle realistic scenarios in the atmosphere. In this project, we are using a newly developed large-eddy simulation framework for high resolution simulations of transient states in the ABL, based on the GPU-accelerated CFD code Neko. The framework has been tested in canonical cases and a paper documenting the performance has been published. Now, the model is being used for two parallel projects: to simulate a full diurnal cycle including transitions between nighttime and daytime boundary layers – characterised by very different turbulent length- and timescales – and to simulate scalar transport in the atmosphere to prepare for implementation of aerosol and cloud physics in the model, moving towards the implementation of the innovative super-droplet method in Neko.