Polarization of Sky Light at Tôkyô

[摘要] With the instrument which was made by Dr. Nukiyama, we observed the relation of the polarization and the formation of clouds on clear days.In the daily veriations of the polarization at the zenith, the plane of polarization changed with the variation of the azimuth of the sun, in accordance with Rayleigh's theory. The variations of the polarization were closely connected with the weather conditions.On really clear days the polarization indicated great values and on less-clear and somewhat cloudy days it gave moderate values. The abovementioned facts seem to indicate that when the moisture content in the air rises, it begins to condense on some particles and forms some water droplets before becoming visible clouds of droplets. Accordingly the droplets cause small variations of the polarization.On hazy days the polarization was observed to have smaller values. This, of course, means that the polarization produced by hazy particles is very slight.

[学科分类] 大气科学