Ground Earth measurement for assessment of UV-B forecast quality

• Unité de recherche: COST
• Numéro de projet: C97.0030
• Titre du projet anglais: Ground Earth measurement for assessment of UV-B forecast quality

Mots-clé (Anglais)

UV; ERYTHEMA; MODELING; ENVIRONMENTAL IMPACT

Programme de recherche (Anglais)

COST-Action 713 - Prévision UV-B

Description succincte (Anglais)

See abstract

Partenaires et organisations internationales (Anglais)

A, B, CH, CZ, D, DK, E, FIN, GR, I, PL

Résumé des résultats (Abstract) (Anglais)

The Swiss Atmospheric Radiation Monitoring program (CHARM) includes among others five measuring stations at different elevations and climatological situations, where the direct, diffuse and global broadband irradiances are measured. Co-located are sun photometer / precision filter radiometer measurements, conventional meteorological parameters and in one case the total ozone column. The comparison between direct and diffuse irradiance models output and measurements have been presented, emphasising on the quantitative impacts of albedo, horizon and aerosol optical depth (AOD) on the direct and diffuse irradiance. The amplitude of the albedo effect has been analysed for two stations, and compared with the snow coverage information. Based on aerosols modelling, the AOD extrapolation into the UV range has been improved by using a modified Angström formula and its results have been verified successfully against the direct erythemal irradiance model. Furthermore, when reversing the application of the model, the total ozone column values have been determined and compared with a Brewer measurement, yielding results better than 3%. This conclusive result has enabled the determination of Ozone values at stations where it is not directly measured, providing a geographical variability analysis. Finally, methods have been devised for improving the UV irradiance data quality control through cross checks with other sensitive measurements.

Références bases de données (Anglais)

Swiss Database: COST-DB of the State Secretariat for Education and Research Hallwylstrasse 4 CH-3003 Berne, Switzerland Tel. [phone] Swiss Project-Number: C97.0030