In the present paper, the results of various numerical analysis carried out from the standpoint of energetics for 500 mb level and surface maps from 24th October to 2nd November,1956, are reported. Namely, the spectral distributions of kinetic energy, momentum transfer and the behaviour of energy transformation between the available potential and kinetic energy or within each and further minute features of two domains of wave number and coefficient of friction etc., have been studied, using a modified two-layer model with the simplified ω-equation.
Natural resources in Japan are so poor that water is sometimes considerd as almost the only natural resource in Japan. In Northern Japan, a large percentage of precipitation in winter is in the form of snow, and remains on the ground as a snow deposit. As the mean air-temperature during winter is near freezing point in Northern Japan, the run-off is mainly due to melting snow and is believed to be nearly proportional to the variation of air-temperature. We wish totest this assumption based on some reliable data.
It was already verified that the absolute vorticity is conserved in the sea. The time variation of vorticity ∂η/∂t, is of the order of 10-11sec-2, and the time range for prediction must be shorter than 30months. So we can usefully predict sea conditions after two or three months by numerical method, but a winder area must be observed for this purpose.
In the routine seismological observation, the running speed of the recording paper or film is 1 mm/sec at the highest owing to operational restrictions; consequently, the time accuracy can hardly attain higher than 0.1 sec by the recorder of the conventional type. An accuracy of 0.01 sec is required in the c ontinuous tripartite observation of natural earthquakes. To meet the requirement, an improved optical recording system has been developed; the main features are a horizontal slit in front of the galvanometer mirror and a cylinder lens in front of the recording film, which make the time resolving power of the system as high as the film grains allow. By this system, a time accuracy of 0.01 sec has been made possible even with the ordinary running speed,1 mm/sec. In designing the optical system, the effect of the diffraction has been prudently taken into account.