抄録
The daily percentage variations of the air-earth current were calculated every longitude of 90° over the world, using the percentage variation of the potential of the upper conducting layer (atmospheric total potential) deduced from Carnegie measurements over the oceans, and that of the columnar resistance obtained from the measurements by Sagalyn and Faucher. The results generally represent the world-wide distribution of the measured daily variation curves which were arranged by Israël. This fact generally indicates that the daily percentage variations of the columnar resistance at the most stations over the land area are roughly equal, and also of the same magnitude as the universal daily percentage variation of the atmospheric total potential. However, more detailed discussions by comparing the measured and the calculated results at the urban district of the meridian 135° E show that the daily variations of the air-earth current depend more on the local columnar resistance than the atmospheric total potential, the percentage variation of the former being twice as much magnitude as that of the latter. It is suggested that at the urban district the unclei concentration in the lowest layer of the exchange layer plays an important part in the atmospheric electric current system.
