Water quality assessment using satellite-derived chlorophyll-a within the European directives, in the southeastern Bay of Biscay

• Published in: Marine pollution bulletin 2012-04, Vol.64 (4), p.739-750
• Main Authors: Novoa, S., Chust, G., Sagarminaga, Y., Revilla, M., Borja, A., Franco, J.
• Format: Article
• Language: English
• Subjects: algorithms; Bays; chlorophyll; Chlorophyll - analysis; Chlorophyll-a; coastal water; Environmental Monitoring - instrumentation; Environmental Monitoring - methods; European directives; European Union; moderate resolution imaging spectroradiometer; monitoring; Remote sensing; Satellite Communications; satellites; Seawater - chemistry; surface water; water pollution; Water Quality; Water quality assessment
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2012.01.020

► Implementation of European Directives requires an intensification of water quality monitoring. ► We aimed to assess the ecological status of Basque coastal water bodies using satellite imagery. ► Sea surface satellite-derived chl-a algorithms were compared against in situ measurements. ► The OC5 algorithm corresponded most accurately with in situ measurements performed in the area. ► A chlorophyll-a map was created with this algorithm to apply the classification scheme. The implementation of water quality European Directives requires an intensification of water quality monitoring, within the limits of the Exclusive Economic Zone. Remote sensing technologies can provide a valuable tool for frequent, synoptic, water-quality observations, over large areas. The aim of this study is to assess the ecological status of Basque coastal water bodies using satellite imagery from MODIS sensor, together with optical and chlorophyll-ain situ measurements. Thus, sea surface satellite-derived chl-a algorithms, the OC3 M, OC5 and a Local empirical algorithm, were compared against in situ measurements using satellite in situ match-ups, 90th Percentile (P90) monthly values for the 2005–2010 period. The OC5 algorithm corresponded most accurately with in situ measurements performed in the area, hence, it was selected. A P90 chlorophyll-a map was created with this algorithm to apply the classification scheme required by the directives. The classification of water bodies, based upon satellite-derived chlorophyll-a, could improve considerably the assessment of water quality.