{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:13:29Z","timestamp":1760148809388,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,8]],"date-time":"2023-06-08T00:00:00Z","timestamp":1686182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002341","name":"Academy of Finland","doi-asserted-by":"publisher","award":["338150","335943"],"award-info":[{"award-number":["338150","335943"]}],"id":[{"id":"10.13039\/501100002341","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The International Cooperative Engagement Program","award":["338150","335943"],"award-info":[{"award-number":["338150","335943"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Maritime safety relies on navigation, detection, and radio communication technologies that function through electromagnetic radiation. Propagation of electromagnetic radiation can be impacted by a disruptive phenomenon known as ducting. Our four-week study using a X-band coastal radar and various meteorological and marine observations, including vertical profiles of temperature, humidity and wind, in early spring 2022 concluded that the combination of measurements at the Ut\u00f6 observatory provides a reliable means of detecting ducting in the Archipelago Sea. The modified refractivity calculated from the vertical profiles for the 22\u201359 m and 32\u201359 m altitude layers and coastal radar over-the-horizon observations agree 77% and 85% of the time, respectively. As such, the modified refractivity gradient can be considered a good indicator for over-the-horizon detection with the Ut\u00f6 coastal radar over the open sea. The horizontal wind profiles also revealed a low-level jet at the radar height that often coincided with the ducting observations. To quantify the results, we created an empirical ducting index which showed that ducting is spatially variable, showing the capabilities of the Ut\u00f6 observatory for research oriented towards monitoring and improving maritime safety and security.<\/jats:p>","DOI":"10.3390\/rs15122989","type":"journal-article","created":{"date-parts":[[2023,6,8]],"date-time":"2023-06-08T02:58:32Z","timestamp":1686193112000},"page":"2989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Ut\u00f6 Observatory for Analysing Atmospheric Ducting Events over Baltic Coastal and Marine Waters"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2363-2647","authenticated-orcid":false,"given":"Laura","family":"Rautiainen","sequence":"first","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"given":"Jani","family":"Tyynel\u00e4","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"given":"Mikko","family":"Lensu","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"given":"Simo","family":"Siiri\u00e4","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"given":"Ville","family":"Vakkari","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"},{"name":"Atmospheric Chemistry Research Group, Chemical Resource Beneficiation, North-West University, Potchefstroom 2520, South Africa"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9834-5100","authenticated-orcid":false,"given":"Ewan","family":"O\u2019Connor","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3449-7559","authenticated-orcid":false,"given":"Karoliina","family":"H\u00e4m\u00e4l\u00e4inen","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"given":"Harry","family":"Lonka","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"given":"Ken","family":"Stenb\u00e4ck","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3667-2071","authenticated-orcid":false,"given":"Jarmo","family":"Koistinen","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3340-4648","authenticated-orcid":false,"given":"Lauri","family":"Laakso","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Erik Palmenin Aukio 1, 00560 Helsinki, Finland"},{"name":"Atmospheric Chemistry Research Group, Chemical Resource Beneficiation, North-West University, Potchefstroom 2520, South Africa"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,8]]},"reference":[{"key":"ref_1","unstructured":"Linquist, T. 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