A nonlocal three‐dimensional turbulence parameterization (NLT3D) for numerical weather prediction models

With increasing resolution of numerical weather prediction (NWP) models, classical subgrid-scale processes become increasingly resolved on the model grid. In particular, turbulence in planetary boundary layer (PBL) is vertically already partially contemporary models. For local PBL schemes, resulting up-gradient heat transports cannot be treated correctly. Thus, nonlocal schemes have been developed past. As horizontal grid sizes NWP models smaller than a few kilometers, large eddies will also start to direction. A very flexible way formulate turbulent exchange transilient matrix method, which used here develop new parameterization. The NLT 3 D scheme applies mixing matrices all three dimensions. We compare results WRF real-case simulations including our scheme, (MYNN), and an existing one-dimensional (ACM2) with observations from field campaigns over homogeneous terrain (CASES-99) complex (CAPTEX). Over terrain, similarly well capture observed surface fluxes radiosonde profiles, whereas more differences obvious. During tracer release experiment (CAPTEX) Appalachian mountain region, vertical extent turn out decisive reproduce advection speed tracer-marked air mass. Deeper not only accelerates winds but enables travel faster at higher altitudes then mix back ground. version standard Smagorinsky diffusion (NLT 1 ) demonstrate, simulating three-dimensional can beneficial kilometers.