{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T13:17:39Z","timestamp":1782739059878,"version":"3.54.5"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,2,8]],"date-time":"2021-02-08T00:00:00Z","timestamp":1612742400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"GEPENA Research Group TEP-957 (Junta de Andaluc\u00eda and University of Cordoba)","award":["TEP-957"],"award-info":[{"award-number":["TEP-957"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The last decades have been successively warmer at the Earth\u2019s surface. An increasing interest in climate variability is appearing, and many research works have investigated the main effects on different climate variables. Some of them apply complex networks approaches to explore the spatial relation between distinct grid points or stations. In this work, the authors investigate whether topological properties change over several years. To this aim, we explore the application of the horizontal visibility graph (HVG) approach which maps a time series into a complex network. Data used in this study include a 60-year period of daily mean temperature anomalies in several stations over the Iberian Peninsula (Spain). Average degree, degree distribution exponent, and global clustering coefficient were analyzed. Interestingly, results show that they agree on a lack of significant trends, unlike annual mean values of anomalies, which present a characteristic upward trend. The main conclusions obtained are that complex networks structures and nonlinear features, such as weak correlations, appear not to be affected by rising temperatures derived from global climate conditions. Furthermore, different locations present a similar behavior and the intrinsic nature of these signals seems to be well described by network parameters.<\/jats:p>","DOI":"10.3390\/e23020207","type":"journal-article","created":{"date-parts":[[2021,2,9]],"date-time":"2021-02-09T23:43:16Z","timestamp":1612914196000},"page":"207","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Analysis of Air Mean Temperature Anomalies by Using Horizontal Visibility Graphs"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2624-7397","authenticated-orcid":false,"given":"Javier","family":"G\u00f3mez-G\u00f3mez","sequence":"first","affiliation":[{"name":"GEPENA Research Group, University of Cordoba, Gregor Mendel Building (3rd Floor), Campus Rabanales, 14071 Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rafael","family":"Carmona-Cabezas","sequence":"additional","affiliation":[{"name":"GEPENA Research Group, University of Cordoba, Gregor Mendel Building (3rd Floor), Campus Rabanales, 14071 Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4885-6065","authenticated-orcid":false,"given":"Elena","family":"S\u00e1nchez-L\u00f3pez","sequence":"additional","affiliation":[{"name":"GEPENA Research Group, University of Cordoba, Gregor Mendel Building (3rd Floor), Campus Rabanales, 14071 Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2091-6708","authenticated-orcid":false,"given":"Eduardo","family":"Guti\u00e9rrez de Rav\u00e9","sequence":"additional","affiliation":[{"name":"GEPENA Research Group, University of Cordoba, Gregor Mendel Building (3rd Floor), Campus Rabanales, 14071 Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4498-8797","authenticated-orcid":false,"given":"Francisco Jos\u00e9","family":"Jim\u00e9nez-Hornero","sequence":"additional","affiliation":[{"name":"GEPENA Research Group, University of Cordoba, Gregor Mendel Building (3rd Floor), Campus Rabanales, 14071 Cordoba, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1016\/0169-8095(94)00083-P","article-title":"Geographical distribution of changes in maximum and minimum temperatures","volume":"37","author":"Horton","year":"1995","journal-title":"Atmos. 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