Articles | Volume 23, issue 15
https://doi.org/10.5194/bg-23-5377-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/bg-23-5377-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Aug 2026
Research article |
| 04 Aug 2026
| 04 Aug 2026
Selective accumulation of dissolved organic matter in the sea surface microlayer: integrated multi-spectral CDOM and FDOM characterization and a novel FDOM/CDOM index at a Mediterranean coastal site
Institute of Oceanography, Hellenic Centre for Marine Research, 47 km Athinon – Souniou ave., 19013 Anavyssos, Greece
Eleni Tzempelikou
Institute of Oceanography, Hellenic Centre for Marine Research, 47 km Athinon – Souniou ave., 19013 Anavyssos, Greece
Christina Zeri
Institute of Oceanography, Hellenic Centre for Marine Research, 47 km Athinon – Souniou ave., 19013 Anavyssos, Greece
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We present oceanographic measurements obtained during two surveillance cruises conducted in June and September 2021 in the Red Sea and the Arabian Gulf. It is the first multidisciplinary survey within the Saudi Arabian coastal zone, extending from near the Saudi–Jordanian border in the north of the Red Sea to the south close to the Saudi--Yemen border and in the Arabian Gulf. The objective was to record the pollution status along the coastal zone of the kingdom related to specific pressures.
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Short summary
Chromophoric dissolved organic matter dynamics (CDOM) in the sea surface microlayer (SML) and underlying water were examined at a coastal site. The SML was enriched in dissolved organic carbon (DOC), CDOM and fluorescent dissolved organic matter (FDOM). Optical indices and FDOM/CDOM index showed wavelength-dependent enrichment and decoupling of CDOM-FDOM, suggesting that photodegradation, biological processes and atmospheric inputs shape DOC pool beyond simple upward flux from underlying waters.
Chromophoric dissolved organic matter dynamics (CDOM) in the sea surface microlayer (SML) and...
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