2026-04-13T15:07:50Zhttps://recercat.cat/oai/request

oai:recercat.cat:10256/76932024-06-14T09:36:29Zcom_2072_452955com_2072_2054col_2072_453063

2024-06-14T09:36:29Z urn:hdl:10256/7693 A Method for Sky-Condition Classification from Ground-Based Solar Radiation Measurements Calbó Angrill, Josep González Gutiérrez, Josep Abel Pagès, David Radiació solar Núvols Clouds Meteorologia -- Observacions Meteorology -- Observations Sun -- Radiation Identification of clouds from satellite images is now a routine task. Observation of clouds from the ground, however, is still needed to acquire a complete description of cloud conditions. Among the standard meteorologicalvariables, solar radiation is the most affected by cloud cover. In this note, a method for using global and diffuse solar radiation data to classify sky conditions into several classes is suggested. A classical maximum-likelihood method is applied for clustering data. The method is applied to a series of four years of solar radiation data and human cloud observations at a site in Catalonia, Spain. With these data, the accuracy of the solar radiation method as compared with human observations is 45% when nine classes of sky conditions are to be distinguished, and it grows significantly to almost 60% when samples are classified in only five different classes. Most errors are explained by limitations in the database; therefore, further work is under way with a more suitable database 2024-06-14T09:36:29Z 2024-06-14T09:36:29Z 2001 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/10256/7693 info:eu-repo/semantics/altIdentifier/doi/10.1175/1520-0450(2001)040<2193:AMFSCC>2.0.CO;2 info:eu-repo/semantics/altIdentifier/issn/1558-8432 info:eu-repo/semantics/altIdentifier/eissn/1558-8424 Tots els drets reservats info:eu-repo/semantics/openAccess American Meteorological Society © Journal of Applied Meteorology and Climatology, 2001, vol. 40, núm. 12, p. 2193-2199 Articles publicats (D-F)