{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T16:11:59Z","timestamp":1772813519943,"version":"3.50.1"},"reference-count":71,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,8,10]],"date-time":"2018-08-10T00:00:00Z","timestamp":1533859200000},"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\/H017348\/1"],"award-info":[{"award-number":["NE\/H017348\/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>Increasing atmospheric CO2 concentrations are resulting in a reduction in seawater pH, with potential detrimental consequences for marine organisms. Improved efforts are required to monitor the anthropogenically driven pH decrease in the context of natural pH variations. We present here a high resolution surface water pH data set obtained in summer 2011 in North West European Shelf Seas. The aim of our paper is to demonstrate the successful deployment of the pH sensor, and discuss the carbonate chemistry dynamics of surface waters of Northwest European Shelf Seas using pH and ancillary data. The pH measurements were undertaken using spectrophotometry with a Lab-on-Chip pH sensor connected to the underway seawater supply of the ship. The main processes controlling the pH distribution along the ship\u2019s transect, and their relative importance, were determined using a statistical approach. The pH sensor allowed 10 measurements h\u22121 with a precision of 0.001 pH units and a good agreement with pH calculated from a pair of discretely sampled carbonate variables dissolved inorganic carbon (DIC), total alkalinity (TA) and partial pressure of CO2 (pCO2) (e.g., pHDICpCO2). For this summer cruise, the biological activity formed the main control on the pH distribution along the cruise transect. This study highlights the importance of high quality and high resolution pH measurements for the assessment of carbonate chemistry dynamics in marine waters.<\/jats:p>","DOI":"10.3390\/s18082622","type":"journal-article","created":{"date-parts":[[2018,8,10]],"date-time":"2018-08-10T10:52:01Z","timestamp":1533898321000},"page":"2622","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["High Resolution pH Measurements Using a Lab-on-Chip Sensor in Surface Waters of Northwest European Shelf Seas"],"prefix":"10.3390","volume":"18","author":[{"given":"Victoire M. C.","family":"R\u00e9rolle","sequence":"first","affiliation":[{"name":"National Oceanography Centre, Southampton, University of Southampton, Southampton SO14 3ZH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3061-2767","authenticated-orcid":false,"given":"Eric P.","family":"Achterberg","sequence":"additional","affiliation":[{"name":"National Oceanography Centre, Southampton, University of Southampton, Southampton SO14 3ZH, UK"},{"name":"GEOMAR Helmholtz Centre for Ocean Research Kiel, 24148 Kiel, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3318-5462","authenticated-orcid":false,"given":"Mariana","family":"Ribas-Ribas","sequence":"additional","affiliation":[{"name":"National Oceanography Centre, Southampton, University of Southampton, Southampton SO14 3ZH, UK"},{"name":"Institute for Chemistry and Biology of the Marine Environment, University of Oldenburg, 26382 Wilhelmshaven, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3949-3802","authenticated-orcid":false,"given":"Vassilis","family":"Kitidis","sequence":"additional","affiliation":[{"name":"Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ian","family":"Brown","sequence":"additional","affiliation":[{"name":"Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9234-5337","authenticated-orcid":false,"given":"Dorothee C. E.","family":"Bakker","sequence":"additional","affiliation":[{"name":"Centre of Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gareth A.","family":"Lee","sequence":"additional","affiliation":[{"name":"Centre of Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matthew C.","family":"Mowlem","sequence":"additional","affiliation":[{"name":"National Oceanography Centre, Southampton SO14 3ZH, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"165","DOI":"10.5194\/essd-5-165-2013","article-title":"The global carbon budget 1959\u20132011","volume":"5","author":"Andres","year":"2013","journal-title":"Earth Syst. 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