CMG: Use of Nonlinear Analysis to Characterize the Behavior and Predictability of the Atmospheric Boundary Layer

University Of Alabama In Huntsville, Huntsville AL

Investigators

Abstract

This project is an investigation of the dependence of the behavior of the atmospheric boundary layer on a variety of parameters including surface heat capacity, Rossby number, long wave radiation and heating rate, as well as the dependence of the behavior in numerical models on vertical discretization. The approach used is that of a numerical bifurcation analysis of the one-dimensional system of partial differential equations that describe the atmospheric boundary layer and a comparison of the results to integrations of horizontally homogeneous implementations of MM5 or WRF. The approach to be used will be similar to that used by one of the investigators to look at the role of geostrophic wind and roughness length as bifurcation parameters. On the mathematical side, the project will apply and extend research on the use of sub-space projection to extend continuation schemes for large systems. Some of the bifurcation analysis tools developed will be useful in other atmospheric and oceanic studies. One consequence of this work should be a better understanding of the nonlinear behavior of the atmospheric boundary layer which can then be incorprated into numerical weather prediction models to produce more accurate predictions of surface temperatures, especially at night.