{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T12:02:09Z","timestamp":1776254529394,"version":"3.50.1"},"reference-count":83,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,2,22]],"date-time":"2019-02-22T00:00:00Z","timestamp":1550793600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000270","name":"Natural Environment Research Council","doi-asserted-by":"publisher","award":["NE\/R003521\/1"],"award-info":[{"award-number":["NE\/R003521\/1"]}],"id":[{"id":"10.13039\/501100000270","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Two expanding areas of science and technology are citizen science and three-dimensional (3D) printing. Citizen science has a proven capability to generate reliable data and contribute to unexpected scientific discovery. It can put science into the hands of the citizens, increasing understanding, promoting environmental stewardship, and leading to the production of large databases for use in environmental monitoring. 3D printing has the potential to create cheap, bespoke scientific instruments that have formerly required dedicated facilities to assemble. It can put instrument manufacturing into the hands of any citizen who has access to a 3D printer. In this paper, we present a simple hand-held device designed to measure the Secchi depth and water colour (Forel Ule scale) of lake, estuarine and nearshore regions. The device is manufactured with marine resistant materials (mostly biodegradable) using a 3D printer and basic workshop tools. It is inexpensive to manufacture, lightweight, easy to use, and accessible to a wide range of users. It builds on a long tradition in optical limnology and oceanography, but is modified for ease of operation in smaller water bodies, and from small watercraft and platforms. We provide detailed instructions on how to build the device and highlight examples of its use for scientific education, citizen science, satellite validation of ocean colour data, and low-cost monitoring of water clarity, colour and temperature.<\/jats:p>","DOI":"10.3390\/s19040936","type":"journal-article","created":{"date-parts":[[2019,2,22]],"date-time":"2019-02-22T11:26:14Z","timestamp":1550834774000},"page":"936","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["A Printable Device for Measuring Clarity and Colour in Lake and Nearshore Waters"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5134-8291","authenticated-orcid":false,"given":"Robert","family":"Brewin","sequence":"first","affiliation":[{"name":"Plymouth Marine Laboratory, Plymouth, Devon PL1 3DH, UK"},{"name":"National Centre for Earth Observation, Plymouth Marine Laboratory, Plymouth, Devon PL1 3DH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thomas","family":"Brewin","sequence":"additional","affiliation":[{"name":"Chatham and Clarendon Grammar School, Ramsgate, Kent CT11 9BB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joseph","family":"Phillips","sequence":"additional","affiliation":[{"name":"Chatham and Clarendon Grammar School, Ramsgate, Kent CT11 9BB, UK"},{"name":"Faculty of Science and Technology, Bournemouth University, Bournemouth, Dorset BH12 5BB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sophie","family":"Rose","sequence":"additional","affiliation":[{"name":"Chatham and Clarendon Grammar School, Ramsgate, Kent CT11 9BB, UK"},{"name":"Faculty of Science and Technology, Bournemouth University, Bournemouth, Dorset BH12 5BB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1396-3645","authenticated-orcid":false,"given":"Anas","family":"Abdulaziz","sequence":"additional","affiliation":[{"name":"CSIR-National Institute of Oceanography, Regional Centre Kochi, Kerala 682018, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Werenfrid","family":"Wimmer","sequence":"additional","affiliation":[{"name":"Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, Hampshire SO14 3ZH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3586-192X","authenticated-orcid":false,"given":"Shubha","family":"Sathyendranath","sequence":"additional","affiliation":[{"name":"Plymouth Marine Laboratory, Plymouth, Devon PL1 3DH, UK"},{"name":"National Centre for Earth Observation, Plymouth Marine Laboratory, Plymouth, Devon PL1 3DH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Trevor","family":"Platt","sequence":"additional","affiliation":[{"name":"Plymouth Marine Laboratory, Plymouth, Devon PL1 3DH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,22]]},"reference":[{"key":"ref_1","first-page":"205","article-title":"Relazione delle esperienze fatte a bordo della pontificia pirocorvetta Imacolata Concezione per determinare la trasparenza del mare","volume":"Volume 20","author":"Secchi","year":"1985","journal-title":"Il Nuovo Cimento Giornale de Fisica, Chimica e Storia Naturale"},{"key":"ref_2","first-page":"25","article-title":"Une nouvelle forme de la gamme de couleur pour l\u2019\u00e9tude de l\u2019eau des lacs","volume":"6","author":"Forel","year":"1890","journal-title":"Archives des Sciences Physiques et Naturelles\/Soci\u00e9t\u00e9 de Physique et d\u2019Histoire Naturelle de Gen\u00e8ve"},{"key":"ref_3","unstructured":"Ule, W. 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