This paper describes an extensive experimental study of two parameters which have recently been developed and proposed as useful statistical and descriptive indexes of net and solar radiation relations over natural surfaces. These two parameters are the "heating coefficient, " proposed to be indicative of the rate of change of net long-wave radiation loss per unit increase in net irradiation; and the "long-wave exchange coefficient", proposed to be indicative of the rate of change of net long-wave radiation income per unit increase in net solar irradiation. The results of the study indicate that both the heating coefficient and the long-wave exchange coefficient are found to be less than adequate in both the statistical and descriptive categories. It is further demonstrated that no other single parameter should be expected to be developed to do what these parameters fail to do.
The characteristics of the tropical cloudiness on the equatorial cloud band of the northern hemisphere were investigated by using the SSCC pictures recorded by NASA from January 1 to June 30 in 1967. The cloudiness variation with approximately semi-monthly period was predominantly detected from the spectrum analysis. This variation is expected to be deviled into three wave modes from rough analysis of wave propagation, one of which travels eastwards, others of which propagate westwards.
Observations of the number concentration of -20°C ice nuclei were carried out at Syowa Station (69°00'S, 39°35'E), Antarctica from the beginning of February 1968 to the end of January 1969. Especially, concerning the observation, special attention was paid to clarify the annual variation, the relation between meteor showers and the remarkable increases of ice nuclei and the effect of pre-activation of ice nuclei. Three different methods of the same two equipment were adopted, namely, the original, pre-heating and direct methods. As a result, it was shown that the number concentration of -20°C ice nuclei increased in the winter season and decreased in the summer season in Antarctica. This means that the number concentration of ice nuclei increases when the observing station is under a condition of polar high pressure. As regards the relationship between meteor showers and the increases of ice nuclei, the relation was poor. Furthermore, it was expected that there were a number of minute ice particles and pre-activated ice nuclei which acted as ice nuclei in a broad sense in the free atmosphere in the winter season in Antarctica and the number concentration of these would be higher than those of natural ice nuclei in the cold regions.
Two series of experiments were carried out in purpose to discriminate the effect of the thermal conductivity of the atmosphere from the effect of vapor diffusivity on the shape of growing ice crystals from the vapor phase. In a series of experiments ice crystals were formed in helium-argon gas mixtures under conditions of a constant vapor diffusivity with varying thermal conductivities. Another series of experiments were made under conditions of a constant thermal conductivity with varying vapor diffusivities. In each experiment ice crystals were nucleated by seeding of silver iodide smoke. In order to avoid contamination of impurity vapor, the replication technique of ice crystal was not used. Ice crystals were directly photographed from outside through a glass window placed at the bottom of a cold chamber. It has been found that skeletal structures of ice crystals grew more significantly with increasing thermal conductivity while skeletal structures faded out with increasing vapor diffusivity.
Considerable electrical disturbance was observed in the measurement of space charge due to the formation of ice crystals in a cold box, when seeding for the ice crystals was made by blocks of dry ice. Because it was considered that electrical disturbance was related to the electrification of the dry ice, laboratory experiments were made to examine the consideration. As a result, it was confirmed that dry ice was electrified negatively if it is evaporated in dry air, while it was charged positively if frost condenses on its surface in moist air.
Horizontal and vertical distributions of aerosols were measured with a condensation nucleus counter of Gardner type, in Sapporo in the winter season of 1970. The concentration of aerosols in the city was in the order of 104cm-3 in the nighttime and 105cm-3 in the daytime, respectively. The concentration in the suburbs of the city was in the order of 103cm-3 both in the day and night time. It was noted that the distributions were strongly influenced by meteorological conditions, that is, air with high concentration of aerosols was ransported far to leeward by the surface wind. It was also noted that the concentration increased by photochemical reaction by about one order, while it decreased by snowfalls also by about one order.