Improved Parameterization of Stably Stratified Boundary Layer Turbulence in Atmospheric Models
Author | : |
Publisher | : |
Total Pages | : 7 |
Release | : 2005 |
ISBN-10 | : OCLC:64435284 |
ISBN-13 | : |
Rating | : 4/5 (84 Downloads) |
Book excerpt: In the course of the project, our research has spanned over several areas encompassing theoretical, numerical and phenomenological aspects of stably stratified atmospheric boundary layers (SBLs). We have laid a solid foundation for studying stably stratified turbulence in the framework of a Quasi-Normal Scale Elimination theory (QNSE) developed by us. We consider the QNSE theory as a major breakthrough in this field. Being maximally proximate to the first principles, the theory penetrates very deeply into the physics of anisotropic turbulence and turbulence-wave interaction yet its calculations can be carried out analytically almost to the final results. We have performed initial analytical exploration of the new theory and implemented it in Reynolds-averaged, Navier-Stokes (RANS) models whose predictions agree well with data collected in BASE and SHEBA campaigns. In addition, we investigated non-local features of stable planetary boundary layers (PBLs) caused by semi-organized structures overlooked in traditional boundary-layer meteorology and in PBL schemes currently used in atmospheric models. Theoretical developments focused on basic length scales characterizing semi-organized structures and corresponding revision of classical similarity theory, PBL depth equations, and bulk resistance and heat/mass transfers laws.