Simulation Experiments with a 12-Layer Stratospheric Global Circulation Model. I. Dynamical Effect of the Earth's Orography and Thermal Influence of Continentality

Abstract

Abstract To evaluate the role of the earth's orography in the stratospheric general circulation, we conducted numerical experiments simulating January climate with and without mountains in a 12-layer NCAR global circulation model, with the top of the atmosphere extending to 36 km. The model has a spherical horizontal mesh increment of 5° in longitude and latitude and a vertical grid increment of 3 km. The model includes various physics: solar and terrestrial radiation, surface and planetary boundary layers, large-scale precipitation and cloud calculations in the troposphere, surface temperature calculations over land and snow-ice surfaces, convective adjustment, and subgrid-scale transport of heat, water vapor and momentum. The continentality of the earth's surface is incorporated by specifying the ocean surface temperature and a realistic earth's orography for the mountain case and a flat surface over land for the no-mountain case. Mean January conditions of simulation are specified by the declination of...