Preliminary communication
ERYTHEMALLY EFFECTIVE UV RADIATION IN ZAGREB DURING MAY 1999
Ivana Herceg Bulić
; Andrija Mohorovičić Geophysical Institute, Faculty of Science, University of Zagreb Horvatovac bb, 10000 Zagreb, Croatia
Abstract
This paper is a presentation of erythemally effective irradiance measurements carried out in Zagreb, Croatia. The amounts of UV irradiance are expressed as erythemally effective dosages in MEDh-1, where one MED equals 250 Jm-2. The paper presents the results obtained in May 1999. The maximal and minimal noontime means of erythemally effective irradiance were 3.149 MEDh-1 and 0.508 MEDh-1, respectively. The daily course in clear sky conditions has a bell-shape distribution. For cloudy sky, the daily course curve is asymmetrical with reduced amounts of erythemally effective dosages.
Simultaneous measurements of global irradiation and relative humidity were used to examine their connection with erythemally effective dosages. The simple linear regression method has shown that the relationship between erythemally effective dosages (predictand) and global radiation (predictor) gives better results than the same method with relative humidity as a predictand. On the other hand, the highest value of the correlation coefficient was obtained by multiple linear regression including both predictors. However, the improvement was not significant compared to the results obtained by simple linear regression with global radiation as the only predictand.
Keywords
erythemally effective irradiance; global irradiation,relative humidity
Hrčak ID:
67415
URI
Publication date:
19.12.2001.
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