@article{oai:nagasaki-u.repo.nii.ac.jp:00007962,
 author = {Arao, Kimio},
 journal = {長崎大学教育学部自然科学研究報告, Science bulletin of the Faculty of Education, Nagasaki University},
 month = {Feb},
 note = {The measurements of direct solar radiation by a silver disc pyrheliometer and of solar radiation at a wavelength of 0.5 μ by a Volz sunphotometer have been made at Nagasaki since 1971 and 1969, respectively. Two kinds of turbidity coefficient are evaluated from these data and the secular variation of atmospheric turbidity estimated from two sets of direct solar radiation data taken at Nagasaki in the years 1937-38 and 1972-73 is also given. As a result, the atmospheric turbidity at Nagasaki is small compared with those of other cities, but the present amount of aerosols is about 2.3 times as large as that of the prewar days., 長崎大学教育学部自然科学研究報告. vol.26, p.109-114; 1975},
 pages = {109--114},
 title = {Secular and Recent Variations of Atmospheric Turbidity at Nagasaki},
 volume = {26},
 year = {1975}
}