title: [Observation and analysis of solar ultraviolet irradiance spectrum in Chengdu area].
abstract: The solar ultraviolet irradiance spectrum in Chengdu area from March to July in 2006 was observed with an ultraviolet CCD optical multi-channel analyzer. According to the observation results, some analysis of the basic characteristics was made. The analysis of the solar ultraviolet irradiance spectrum showed that the solar ultraviolet irradiance is weak in the morning and in the evening but strong at noon, reaches the strongest point in June, and reversely correlates with the change in SZA (solar zenith angle); the ratio of irradiance flux of UVB to UVA is less than 0.04, and usually, the ratio in the afternoon is bigger than that in the morning in sunny days; Fogs can cause the ratio to increase, the reason is that fogs show stronger influence on attenuation of UVA than UVB; Clouds absorbed the solar ultraviolet irradiance greatly.
authors.affiliation: Department of Physics, Sichuan University, Chengdu 610064, China. peng3219@163.com
authors.forename: Peng
authors.initials: P
authors.lastname: Sun
authors.forename: Jie
authors.initials: J
authors.lastname: He
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Zhao
authors.forename: Hao-Yi
authors.initials: HY
authors.lastname: Zuo
authors.forename: Jing-Guo
authors.initials: JG
authors.lastname: Yang
mesh_terms: D002681:China; D004784:Environmental Monitoring; D014466:Ultraviolet Rays