<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-04-13T02:51:22Z</responseDate><request verb="GetRecord" identifier="oai:www.recercat.cat:10256/7693" metadataPrefix="qdc">https://recercat.cat/oai/request</request><GetRecord><record><header><identifier>oai:recercat.cat:10256/7693</identifier><datestamp>2024-06-14T09:36:29Z</datestamp><setSpec>com_2072_452955</setSpec><setSpec>com_2072_2054</setSpec><setSpec>col_2072_453063</setSpec></header><metadata><qdc:qualifieddc xmlns:qdc="http://dspace.org/qualifieddc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://purl.org/dc/elements/1.1/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dc.xsd http://purl.org/dc/terms/ http://dublincore.org/schemas/xmls/qdc/2006/01/06/dcterms.xsd http://dspace.org/qualifieddc/ http://www.ukoln.ac.uk/metadata/dcmi/xmlschema/qualifieddc.xsd">
   <dc:title>A Method for Sky-Condition Classification from Ground-Based Solar Radiation Measurements</dc:title>
   <dc:creator>Calbó Angrill, Josep</dc:creator>
   <dc:creator>González Gutiérrez, Josep Abel</dc:creator>
   <dc:creator>Pagès, David</dc:creator>
   <dc:subject>Radiació solar</dc:subject>
   <dc:subject>Núvols</dc:subject>
   <dc:subject>Clouds</dc:subject>
   <dc:subject>Meteorologia -- Observacions</dc:subject>
   <dc:subject>Meteorology -- Observations</dc:subject>
   <dc:subject>Sun -- Radiation</dc:subject>
   <dcterms:abstract>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</dcterms:abstract>
   <dcterms:dateAccepted>2024-06-14T09:36:29Z</dcterms:dateAccepted>
   <dcterms:available>2024-06-14T09:36:29Z</dcterms:available>
   <dcterms:created>2024-06-14T09:36:29Z</dcterms:created>
   <dcterms:issued>2001</dcterms:issued>
   <dc:type>info:eu-repo/semantics/article</dc:type>
   <dc:type>info:eu-repo/semantics/publishedVersion</dc:type>
   <dc:identifier>http://hdl.handle.net/10256/7693</dc:identifier>
   <dc:relation>info:eu-repo/semantics/altIdentifier/doi/10.1175/1520-0450(2001)040&lt;2193:AMFSCC>2.0.CO;2</dc:relation>
   <dc:relation>info:eu-repo/semantics/altIdentifier/issn/1558-8432</dc:relation>
   <dc:relation>info:eu-repo/semantics/altIdentifier/eissn/1558-8424</dc:relation>
   <dc:rights>Tots els drets reservats</dc:rights>
   <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
   <dc:publisher>American Meteorological Society</dc:publisher>
   <dc:source>© Journal of Applied Meteorology and Climatology, 2001, vol. 40, núm. 12, p. 2193-2199</dc:source>
   <dc:source>Articles publicats (D-F)</dc:source>
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