{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T10:39:35Z","timestamp":1776335975221,"version":"3.51.2"},"reference-count":58,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2016,10,25]],"date-time":"2016-10-25T00:00:00Z","timestamp":1477353600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"EC","doi-asserted-by":"publisher","award":["agreement n\u00ba 308469"],"award-info":[{"award-number":["agreement n\u00ba 308469"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Marine processes are observed with sensors from both the ground and space over large spatio-temporal scales. Citizen-based contributions can fill observational gaps and increase environmental stewardship amongst the public. For this purpose, tools and methods for citizen science need to (1) complement existing datasets; and (2) be affordable, while appealing to different user and developer groups. In this article, tools and methods developed in the 7th Framework Programme of European Union (EU FP 7) funded project Citclops (citizens\u2019 observatories for coast and ocean optical monitoring) are reviewed. Tools range from a stand-alone smartphone app to devices with Arduino and 3-D printing, and hence are attractive to a diversity of users; from the general public to more specified maker- and open labware movements. Standardization to common water quality parameters and methods allows long-term storage in regular marine data repositories, such as SeaDataNet and EMODnet, thereby providing open data access. Due to the given intercomparability to existing remote sensing datasets, these tools are ready to complement the marine datapool. In the future, such combined satellite and citizen observations may set measurements by the engaged public in a larger context and hence increase their individual meaning. In a wider sense, a synoptic use can support research, management authorities, and societies at large.<\/jats:p>","DOI":"10.3390\/rs8110879","type":"journal-article","created":{"date-parts":[[2016,10,25]],"date-time":"2016-10-25T10:28:49Z","timestamp":1477391329000},"page":"879","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":53,"title":["Citizen Bio-Optical Observations from Coast- and Ocean and Their Compatibility with Ocean Colour Satellite Measurements"],"prefix":"10.3390","volume":"8","author":[{"given":"Julia","family":"Busch","sequence":"first","affiliation":[{"name":"Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Schleusenstra\u00dfe 1, Wilhelmshaven 26382, Germany"},{"name":"Life Sciences and Chemistry, Jacobs University, Campus Ring 1, Bremen 28759, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raul","family":"Bardaji","sequence":"additional","affiliation":[{"name":"Institue of Marine Sciences, Spanish National Research Council (ICM-CSIC), Passeig Maritim de la Barceloneta, Barcelona 08003, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3116-0811","authenticated-orcid":false,"given":"Luigi","family":"Ceccaroni","sequence":"additional","affiliation":[{"name":"1000001 Labs, Alzina 52, Barcelona 08024, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anna","family":"Friedrichs","sequence":"additional","affiliation":[{"name":"Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Schleusenstra\u00dfe 1, Wilhelmshaven 26382, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5818-9836","authenticated-orcid":false,"given":"Jaume","family":"Piera","sequence":"additional","affiliation":[{"name":"Institue of Marine Sciences, Spanish National Research Council (ICM-CSIC), Passeig Maritim de la Barceloneta, Barcelona 08003, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9951-5132","authenticated-orcid":false,"given":"Carine","family":"Simon","sequence":"additional","affiliation":[{"name":"Institue of Marine Sciences, Spanish National Research Council (ICM-CSIC), Passeig Maritim de la Barceloneta, Barcelona 08003, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Thijsse","sequence":"additional","affiliation":[{"name":"MARIS, Kon. Julianalaan 345A, Voorburg 2273 JJ, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1331-9569","authenticated-orcid":false,"given":"Marcel","family":"Wernand","sequence":"additional","affiliation":[{"name":"Royal Netherlands Institute for Sea Research (NIOZ), P.O. Box 59, Den Burg\/Texel 1790 AB, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8901-7567","authenticated-orcid":false,"given":"Hendrik","family":"Van der Woerd","sequence":"additional","affiliation":[{"name":"Institute for Environmental Studies (IVM), VU University Amsterdam, De Boelelaan 1087, Amsterdam 1081 HV, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6018-5030","authenticated-orcid":false,"given":"Oliver","family":"Zielinski","sequence":"additional","affiliation":[{"name":"Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, Schleusenstra\u00dfe 1, Wilhelmshaven 26382, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"329","DOI":"10.5194\/os-5-329-2009","article-title":"Detecting marine hazardous substances and organisms: Sensors for pollutants, toxins, and pathogens","volume":"5","author":"Zielinski","year":"2009","journal-title":"Ocean Sci."},{"key":"ref_2","first-page":"171","article-title":"Bio-optical approaches for the operational assessment of harmful algal blooms","volume":"Volume 46","author":"Watson","year":"2013","journal-title":"Subsea Optics and Imaging"},{"key":"ref_3","unstructured":"Schaechter, M. 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