{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:02:15Z","timestamp":1760148135132,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,3,30]],"date-time":"2023-03-30T00:00:00Z","timestamp":1680134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000016","name":"Canadian Space Agency","doi-asserted-by":"publisher","award":["424328","411797"],"award-info":[{"award-number":["424328","411797"]}],"id":[{"id":"10.13039\/501100000016","id-type":"DOI","asserted-by":"publisher"}]},{"name":"NSERC Discovery","award":["424328","411797"],"award-info":[{"award-number":["424328","411797"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Electron density measured at high latitudes by the Swarm satellites was compared with measurements by the incoherent scatter radars at Resolute Bay and Poker Flat. Overall, the ratio of Swarm-based electron density to that measured by the radars was about 0.5\u20130.6. Smaller ratios were observed at larger electron densities, usually during the daytime. At low electron densities less than 3 \u00d7 1010 m\u22123, the ratios were typically above 1, indicating an overestimation effect. The overestimation effect was stronger at night and for Swarm B. It was more evident at lower solar activity when the electron densities in the topside ionosphere were lower.<\/jats:p>","DOI":"10.3390\/rs15071846","type":"journal-article","created":{"date-parts":[[2023,3,30]],"date-time":"2023-03-30T05:22:14Z","timestamp":1680153734000},"page":"1846","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Validation of Swarm Langmuir Probes by Incoherent Scatter Radars at High Latitudes"],"prefix":"10.3390","volume":"15","author":[{"given":"Hayden","family":"Fast","sequence":"first","affiliation":[{"name":"Institute of Space and Atmospheric Studies, Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3604-4991","authenticated-orcid":false,"given":"Alexander","family":"Koustov","sequence":"additional","affiliation":[{"name":"Institute of Space and Atmospheric Studies, Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada"}]},{"given":"Robert","family":"Gillies","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, Canada"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/j.jastp.2016.05.008","article-title":"Empirical model of the main ionospheric trough for the nighttime winter conditions","volume":"146","author":"Karpachev","year":"2016","journal-title":"J. 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