Chamberlain's method proposed in 1953 to estimate the amount of deposition is examined for practical use, using the method of calculating the dosage of air pollutant developed by Meade. According to Chamberlain's method, the vertical profile of diffusing material does not change by deposition, so a new method is developed so as to modify his method. The results are summarised as follows: (1) The difference between the two methods becomes larger at far down-wind distance from a source in usual deposition velocity (>1.0cm/sec). (2) The vertical profile remains the same in Chamberlain's method but the method presented here shows the profile modified by deposition. (3) The difference is small at short distance, which, however, is not to be ignor ed in dosage analysis.
Temperature variation due to fluctuation of solar radiation on the earth is calculated numerically by assuming a simple heat transfer model. If the amplitude of the change of the solar radiation is equal for various periods, the amplitude of short periodic temperature change becomes small by the effect of heat capacity of the sea water or the earth crust, but the amplitude of long periodic change (longer than about 1, 000∼10, 000 years) tends to a certain same value which is given by quasi-equilibrium state between the solar and the long wave radiation at the earth surface. It is found also, that if there is random variation of yearly solar radiation of about 0.5% in the standard deviation, 40∼80 year cyclic temperature change of about 1°C in amplitude will occur, which is comparable with the observed change of ten-year mean temperature.
Two kinds of special billow clouds were detected by photographic observation. These clouds were in two different layers at altitude estimated to be 1700 and 3000m. The photographs were taken at Numanohata in Southern Hokkaido in July 1963 during a field project on Artificial Fog Dispersal. Analysis revealed that the upper altostratus billow was a lee wave cloud produced by the Hidaka range with a prevailing east wind. The lower stratocumulus billow was in rows in the statically unstable layer of moist unsaturated air. This effect was produced by the wind shear above and below the cloud layer. The direction of this wind shear was nearly perpendicular to the axes of the rows. The distance between each element of the upper altostratus billow was not the same. In some instances, the distance between the elements was nearly twice the wave length. This suggests that a lee wave is not only a simpe sinusoidal wave, but may be distorted, with different amplitudes at each wave crest.
A radiosonde for measuring the electric charge on precipitation elements was designed and individual electric charge in cloud was observed. Three specially designed radiosonde transmitters were used for observation of a thundercloud and cumuli. The general feature of electric charge distribution with height in thundercloud was nearly the same as that given by Simpson and Scrase. The amount of individual electric charge on precipitation particles in thundercloud was determined. A layer of positive electric charge of 1km in thickness at an altitude of 12km is supposed to spread widely in the thunderstorm season.
Aerophotographic survey was applied for the analysis of a remarkable meso-scale line disturbance which developed off the coast of Hokuriku District on 2 February 1964. This paper consists of two parts, i.e, the revision on the method of aerophotogrammetry specially designed for the cloud analysis and its application to the meso analysis. It is found that this aerophotographic method is as useful for the meso-scale phenomena as the radar observation. The existence of active cumulus convection towering as high as 5000 m or more is assertained, even in winter season, within the region of smaller scale disturbance which develops in the vicinity of a cold dome center.