A strategy for improvement of LES prediction of stratocumulus entrainment using the 'one-dimensional turbulence' simulation method

One-Dimensional Turbulence (ODT) is a turbulence simulation model formulated on a one-dimensional (1D) spatial domain. In an ABL context, it is nominally a single-column model representing the vertical structure of the atmosphere, but functionally it has a greater resemblance to large-eddy simulation in some respects. Specifically, ODT is a method for simulating, on an unsteady time-resolved basis, the time evolution of profiles of velocity and other fluid properties that one might measure along a one-dimensional (1D) line of sight through a 3D turbulent flow. In the 1D dynamical process defined by the ODT model, the effects of turbulent 3D eddies associated with real fluid flow are captured by 1D fluid-element rearrangement events that occur over a range of length scales with frequencies that depend on event length scales and instantaneous flow structure. The use of ODT to simulate observations during the DYCOMS-II stratocumulus field study is described, and results illustrating the performance and the unique attributes of ODT are presented.