EFFECTS OF PHYSICAL PROCESSES OF H2O ON THE GENERAL-CIRCULATION OF THE ATMOSPHERE .2.

In Part 1 (Miyoshi and Morita, 1993), we investigated how the general circulation of the atmosphere was affected by all the physical process es of H2O. In this study, we divide all the physical processes of H2O into the radiative process of H2O and the hydrological cycle, and inve stigate the effect of both of the processes separately by a series of GCM experiments. Results are as follows. The north-to-south temperatur e gradient and the zonal wind distribution below 5 km height is strong ly affected by the radiative process of H2O. The strength of the merid ional circulation, the magnitude of the poleward energy transport, the magnitude of the sensible and latent heat fluxes and the magnitude of the diabatic heating rate in the atmosphere also depend on the radiat ive process of H2O. Thus, the differences of the general circulation b etween with and without all the physical processes of H2O is mostly ca used by the radiative process of H2O. The zonal wind distributions abo ve 5 km height, on the other hand, are affected by not only the radiat ive process of H2O but also by the hydrological cycle. Numerical exper iments using a vertically one-dimensional radiative-convective equilib rium model are performed. By comparing the radiative-convective equili brium temperature with the temperature in the GCM, the relation betwee n the poleward heat transport by the dynamics and the physical process es of H2O is also examined. In the experiments without the radiative p rocess of H2O, the temperature near the surface in the GCM is almost t he same as the radiative-convective temperature. At low latitudes, the temperature difference between the GCM and the radiative-convective m odel is larger in the experiments with the radiative process of H2O th an in the experiments without the radiative process of H2O.