{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T19:44:14Z","timestamp":1770752654890,"version":"3.50.0"},"reference-count":28,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,20]],"date-time":"2023-09-20T00:00:00Z","timestamp":1695168000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013704","name":"National Council of Science and Technology (CONACyT)","doi-asserted-by":"publisher","award":["CVU: 859540"],"award-info":[{"award-number":["CVU: 859540"]}],"id":[{"id":"10.13039\/501100013704","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The influence of solar activity on the ionosphere, a critical area of investigation due to its relevance to the Sun\u2013Earth relationship, has been extensively examined through various methodologies. The ability of solar events to induce disturbances in both the ionosphere and the geomagnetic field is widely acknowledged. This specific study focused on sporadic incidents resulting from X-class solar flares that occurred between 2021 and 2022. Utilizing a methodology that involved analyzing data at 5Hz intervals using wavelet algorithms, the data from the GNSS stations of the National Autonomous University of Mexico (UNAM) were investigated. The primary emphasis was on deducing the Total Electron Content (TEC) within the ionosphere. Subsequently, this parameter for each satellite during instances of solar flares was analyzed. The approach uncovered disruptions in the ionosphere triggered by solar flares, even in cases where events transpired at the periphery of the solar disk and were of magnitudes smaller than X2.<\/jats:p>","DOI":"10.3390\/rs15184626","type":"journal-article","created":{"date-parts":[[2023,9,20]],"date-time":"2023-09-20T21:47:03Z","timestamp":1695246423000},"page":"4626","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Analysis of Ionospheric Disturbances during X-Class Solar Flares (2021\u20132022) Using GNSS Data and Wavelet Analysis"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-0254-0702","authenticated-orcid":false,"given":"Charbeth","family":"L\u00f3pez-Urias","sequence":"first","affiliation":[{"name":"Department of Earth and Space Sciences, Autonomous University of Sinaloa, Culiac\u00e1n 80040, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8456-537X","authenticated-orcid":false,"given":"G. Esteban","family":"Vazquez-Becerra","sequence":"additional","affiliation":[{"name":"Department of Earth and Space Sciences, Autonomous University of Sinaloa, Culiac\u00e1n 80040, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5015-402X","authenticated-orcid":false,"given":"Karan","family":"Nayak","sequence":"additional","affiliation":[{"name":"Department of Earth and Space Sciences, Autonomous University of Sinaloa, Culiac\u00e1n 80040, Mexico"}]},{"given":"Rebeca","family":"L\u00f3pez-Montes","sequence":"additional","affiliation":[{"name":"Department of Applied Geophysics, Center for Scientific Research and Higher Education of Ensenada, La Paz 23050, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,20]]},"reference":[{"key":"ref_1","unstructured":"Budden, K.G. (1988). 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