Cloud influence on ultraviolet radiation: impact of cloud amount trends upon ultraviolet radiation

Autor: Nataly Ye. Chubarova, Yelena Nezval
Rok vydání: 1995
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
Popis: According to long-term ultraviolet (UV) observations which have been carried out in the Meteorological Observatory of Moscow State University since 1968 influence of different cloud types and cloud amount on UV radiation has been analyzed. UV transmission by cloudiness (Cq) was shown to have distinct spectral peculiarities. Approximate formulas were carried out for different extended clouds Cq distributions. Cq values were shown to be independent of cloud amount (N) of high plus middle clouds. Nonlinear Cq versus N dependence of low clouds was approximated by analytical equation. It may be used in analysis of possible effects of cloud amount trends. Results of data analysis show positive trends of N in different regions of the world (e.g. dN equals 1 in the USA and Canada. dNlow equals 0.2 and dNlow equals 0.5 per decade for Estonia and Moscow). In Moscow Nlow growth caused 6-8% UV attenuation per decade. Due to nonlinear Cq dependence on N the effect of cloud trends on UV radiation may be stronger in climatic regions characterized by great cloud amount values.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Databáze: OpenAIRE