Climate simulation with more accurate process-level representation at finer resolutions is a pressing need in order to provide actionable information to policy-makers regarding extreme events in a changing climate. Computational limitation is a major obstacle for building high-resolution (HR, here 0.25^o average grid spacing at the equator) models (HRM), especially for the Energy Exascale Earth System Model (E3SM). A more affordable path to HRM is to use a global regionally refined model (RRM), which only simulates a portion of the globe at HR while the remaining is at low-resolution (LR, 1^o). In this study, we compare the E3SM atmosphere model version 1 (EAMv1) RRM with the HR patch over the contiguous United States (CONUS) to its corresponding globally uniform LR and HR configurations, as well as to observations and reanalysis data. The RRM has a significantly reduced computational cost (by about 90% dependent on the HR patch size) relative to the globally uniform HRM. Over the CONUS, we examine the geographic distributions of important dynamical and physical quantities as well as various aspects of precipitation.