A computational scheme of the primitive equation model in the pressure coordinate system is presented. The scheme has the conserving properties for the mass and the energy. The pressure changes at the lower boundary are computed by the tendency equation, in which the orographic effects are included. The formulation of lateral boundary conditions for the telescoping mesh is also presented. The normal flow components at the boundary are determined first by the continuity relation using the solutions inside the smaller area and also the divergence given by the large area solution, and secondly are modified in order to reduce the differences of them from the large area solution. Other variables specified at the boundary are discussed. These treatments do not need artificial smoothing at the boundary.
Dimensionless shear functions, φm, φh and φw, have been obtained as a function of a dimen-sionless length, ξ, by following the method which leads to the KEYPS formula, but with adop-tion of the assumption that Kh/Km and Kw/Km respectively are a function of stability. The obtained formula for φm in stable conditions resulted in the KEYPS formula itself. As is well known it disagrees with observations, so that modification of it was attempted by means of dimensional analysis. Two modified forms have been derived. Comparison of the obtained formulae with observed results by other workers was then made. Finally criticism to the concept of the critical Richardson number was expressed.
The relaxation time of exponential recovery of the electric field after lightning flash occur-ring at the distance beyond 10 km is discussed. The relaxation time decreases with increasing distance, but the values obtained in the present study are found to be about 1.5 to 2 times larger than the values obtained by other workers. For close flashes, the field recoveries show almost linear change with time, which is apparently different from that for distant flashes. It is found that there is a good correlation between the average recovery rate and the occurence frequency of flashes for two storms and that the field recovery rate positively correlates with the regeneration rate of charges in thunderclouds. Hence, it is possible to estimate the regeneration rate of charges in thunderclouds from the counting of the occurrence frequency of flashes for any flash distance. The regeneration rate after lightning flash is found to be about 1-10 coul/sec for the two storms.
The snow caused by the winter-monsoon in Japan was analyzed for chemical constituents, radionuclides and stable isotopes. The chloride in the snow was correlated fairly well with not only sodium of maritime origin but also calcium, sulfate and radionuclides for samples collected during a single snowfall. The rainout process seems to be prevailing over the washout process for the removal of the chemical constituents from the convective cloud. The air mass responsible for making 1kg of snow water was calculated to be about 2000m3 STP from the radon daughter nuclides 210Pb, 210Bi and 210Po in the snow collected at Assabu, Hokkaido. The isotopic composition of the snow is not controlled directly by the temperatures of the sea surface and of the air where the snow is forming as suggested by Isono et al. (1966) but controlled by the rela-tion among water vapor contents in the continental air and in the air transported to the Pacific and the amount of water vapor evaporated from the Japan Sea. The consistency between these results was quantitatively examined by making the budget diagram of water and chemical substances during the winter-monsoon season.
The complex index of refraction of the Martian dust particles suspended in the atmosphere is estimated. Using this parameter, we solve the multiple scattering equations and investigate quantitatively heating of the Martian atmosphere due to absorption of the visible solar radiation. Our results show that the atmosphere is strongly heated up by absorption of solar radiation due to dust, and that the thermal structure of the Martian atmosphere would be almost determined by the balance between heating and cooling caused by radiative effects of dust. It is also pointed out that the thermal effects due to dust would induce strong thermal tide. Analyses of the Mariner 9 data indicate fairly good agreement with our results. A new general circulation model for Mars including the thermal effects of dust should be required at the moment.