Toward the Simulation of the Effects of the Great Lakes on Regional Climate

Abstract

This paper describes a set of numerical experiments aimed at evaluating the feasibility of applying a version of the National Center for Atmospheric Research-Pennsylvania State University regional model (MM4) to regional climate simulation over the Great Lakes Basin. The objectives of this initial modeling investigation are 1) to examine whether the MM4 can capture the primary forcing exerted by the Great Lakes on the regional climate and 2) to evaluate what model resolution and configuration are needed to simulate such forcing. Simulations over the Great Lakes region are conducted with and without representation of the lakes at four model gridpoint resolutions ranging from 15 to 90 km. One experiment at 60-km resolution is discussed in which a one-dimensional thermal eddy diffusion model is interactively coupled to the MM4 to represent the lakes. Initial and lateral boundary conditions necessary to drive these simulations are provided by European Centre for Medium-Range Weather Forecasts (ECMWF)... Abstract This paper describes a set of numerical experiments aimed at evaluating the feasibility of applying a version of the National Center for Atmospheric Research-Pennsylvania State University regional model (MM4) to regional climate simulation over the Great Lakes Basin. The objectives of this initial modeling investigation are 1) to examine whether the MM4 can capture the primary forcing exerted by the Great Lakes on the regional climate and 2) to evaluate what model resolution and configuration are needed to simulate such forcing. Simulations over the Great Lakes region are conducted with and without representation of the lakes at four model gridpoint resolutions ranging from 15 to 90 km. One experiment at 60-km resolution is discussed in which a one-dimensional thermal eddy diffusion model is interactively coupled to the MM4 to represent the lakes. Initial and lateral boundary conditions necessary to drive these simulations are provided by European Centre for Medium-Range Weather Forecasts (ECMWF)...