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6 results on '"Giorgio Dall’Olmo"'

1. Major role of particle fragmentation in regulating biological sequestration of CO 2 by the oceans

Author

Hervé Claustre, Nathan Briggs, Giorgio Dall'Olmo, Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), and Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Total organic carbon, Carbon dioxide in Earth's atmosphere, Multidisciplinary, 010504 meteorology & atmospheric sciences, Mesopelagic zone, 010604 marine biology & hydrobiology, Atmospheric sciences, 01 natural sciences, Fragmentation (mass spectrometry), [SDE]Environmental Sciences, Environmental science, 14. Life underwater, Small particles, Oceanic carbon cycle, 0105 earth and related environmental sciences
Abstract

Breaking up is easy to do Sinking particles transport carbon to the seafloor, where they are buried in sediments and either provide food for benthic organisms or sequester the carbon they contain. However, only ∼30% of the maximum flux reaches depths of a kilometer. This loss cannot be fully accounted for by current measurements. Briggs et al. used data collected by robotic Biogeochemical-Argo floats to quantify total mesopelagic fragmentation and found that this process accounts for roughly half of the observed flux loss (see the Perspective by Nayak and Twardowski). Fragmentation is thus perhaps the most important process controlling the remineralization of sinking organic carbon. Science , this issue p. 791 ; see also p. 738

Published
2020
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2. On the Future of Argo: A Global, Full-Depth, Multi-Disciplinary Array

Author

Jonathan D. Nash, Andreas Sterl, Diarmuid Ó. Conchubhair, Mathieu Belbeoch, Toste Tanhua, Lynne D. Talley, Thierry Carval, Stephanie Waterman, Yueng-Djern Lenn, Kenneth S. Johnson, Ariel Troisi, Virginie Thierry, Sarah G. Purkey, Satya Prakash, Damien Desbruyères, Giorgio Dall'Olmo, Katja Fennel, Robert Hallberg, Gregory C. Johnson, James N. Moum, Ilker Fer, Brian A. King, Gael Forget, Emily L. Shroyer, Toshio Suga, Peter R. Oke, Rik Wanninkhof, Fei Chai, Are Olsen, Emmanuel Boss, Nicolas Kolodziejczyk, Markus Jochum, Sandy J. Thomalla, N. V. Zilberman, Amy F. Waterhouse, Guillaume Maze, Alberto C. Naveira Garabato, Catherine Schmechtig, Thomas W. Trull, Andrew J. Watson, Fabrizio D'Ortenzio, Haili Wang, Kjell Arne Mork, Pedro Vélez-Belchí, Paulo H. R. Calil, Philip Sutton, Jianping Xu, Steven R. Jayne, Tetsuichi Fujiki, Howard J. Freeland, Henry C. Bittig, Cara Wilson, Hervé Claustre, Ichiro Yasuda, Annie P. S. Wong, John M. Toole, Claudia Schmid, Megan Scanderbeg, Marion Gehlen, Raffaele Ferrari, Arne Körtzinger, Toshiyuki Hibiya, Dean Roemmich, Susan Wijffels, Tamaryn Morris, Sylvie Pouliquen, Matthew H. Alford, Takeyoshi Nagai, Waldemar Walczowski, Pierre-Yves Le Traon, Molly O. Baringer, Blair J. W. Greenan, W. Brechner Owens, KiRyong Kang, Jon Turton, Fiona Carse, Shigeki Hosoda, Rama Rao E. Pattabhi, Dorothee C. E. Bakker, Stephen C. Riser, Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Oceans and Atmosphere Flagship [Brisbane], Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), University of California, CSIRO Marine and Atmospheric Research (CSIRO), University of East Anglia [Norwich] (UEA), School of Marine Sciences, University of Maine, Unité de recherche Géosciences Marines (Ifremer) (GM), Oregon State University (OSU), Laboratoire de physique des océans (LPO), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Department of Oceanography [Halifax] (DO), Dalhousie University [Halifax], Bjerknes Centre for Climate Research (BCCR), Department of Biological Sciences [Bergen] (BIO / UiB), University of Bergen (UiB)-University of Bergen (UiB), Massachusetts Institute of Technology (MIT), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Cancer Genetics Branch, National Institute of Health (NIH)-National Human Genome Research Institute (NHGRI), Laboratoire d'Océanographie Physique et Spatiale (LOPS), Helmholtz Centre for Ocean Research [Kiel] (GEOMAR), Biomedical Technology and Cell Therapy Research Laboratory, Montreal, Université Pierre et Marie Curie - Paris 6 (UPMC), Observatoire des sciences de l'univers Ecce Terra [Paris] (ECCE TERRA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Royal Netherlands Meteorological Institute (KNMI), Leibniz-Institut für Meereswissenschaften (IFM-GEOMAR), Southern Ocean Carbon and Climate Observatory, CSIR, Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC), NOAA Atlantic Oceanographic and Meteorological Laboratory (AOML), National Oceanic and Atmospheric Administration (NOAA), Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, Evolution Paris-Seine, Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université des Antilles (UA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Sorbonne Paris Cité (USPC), McMaster University [Hamilton, Ontario], University of California (UC), Géosciences Marines (GM), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Observatoire des sciences de l'univers Ecce Terra [Paris] (OSU ECCE TERRA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Scripps Institution of Oceanography (SIO - UC San Diego), University of California (UC)-University of California (UC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Sorbonne Paris Cité (USPC)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), and Observatoire des sciences de l'univers Ecce Terra (ECCE TERRA)

Subjects
0106 biological sciences, lcsh:QH1-199.5, 010504 meteorology & atmospheric sciences, warming, Computer science, Data management, Matematikk og naturvitenskap: 400::Geofag: 450::Oseanografi: 452 [VDP], Sede Central IEO, Ocean Engineering, lcsh:General. Including nature conservation, geographical distribution, VDP::Oseanografi: 452, Aquatic Science, Oceanography, 01 natural sciences, salinity, Mathematics and natural scienses: 400::Geosciences: 450::Oceanography: 452 [VDP], Basic research, Multidisciplinary approach, Profiling (information science), 14. Life underwater, VDP::Oceanography: 452, lcsh:Science, Argo, 0105 earth and related environmental sciences, Water Science and Technology, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Global and Planetary Change, Multi disciplinary, Oseanografi / Oceanography, business.industry, 010604 marine biology & hydrobiology, temperature, Ocean depth, floats, global, ocean, Sea surface temperature, 13. Climate action, Systems engineering, circulation, lcsh:Q, business, Oseanografi
Abstract

The Argo Program has been implemented and sustained for almost two decades, as a global array of about 4000 profiling floats. Argo provides continuous observations of ocean temperature and salinity versus pressure, from the sea surface to 2000 dbar. The successful installation of the Argo array and its innovative data management system arose opportunistically from the combination of great scientific need and technological innovation. Through the data system, Argo provides fundamental physical observations with broad societally-valuable applications, built on the cost-efficient and robust technologies of autonomous profiling floats. Following recent advances in platform and sensor technologies, even greater opportunity exists now than 20 years ago to (i) improve Argo’s global coverage and value beyond the original design, (ii) extend Argo to span the full ocean depth, (iii) add biogeochemical sensors for improved understanding of oceanic cycles of carbon, nutrients, and ecosystems, and (iv) consider experimental sensors that might be included in the future, for example to document the spatial and temporal patterns of ocean mixing. For Core Argo and each of these enhancements, the past, present, and future progression along a path from experimental deployments to regional pilot arrays to global implementation is described. The objective is to create a fully global, top-to-bottom, dynamically complete, and multidisciplinary Argo Program that will integrate seamlessly with satellite and with other in situ elements of the Global Ocean Observing System (Legler et al., 2015). The integrated system will deliver operational reanalysis and forecasting capability, and assessment of the state and variability of the climate system with respect to physical, biogeochemical, and ecosystems parameters. It will enable basic research of unprecedented breadth and magnitude, and a wealth of ocean-education and outreach opportunities., Sí

Published
2019
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3. Determination of the absorption coefficient of chromophoric dissolved organic matter from underway spectrophotometry

Author

David McKee, Annick Bricaud, Robert J. W. Brewin, Francesco Nencioli, Rüdiger Röttgers, Catherine Mitchell, Gavin H. Tilstone, Emmanuel Boss, Emanuele Organelli, Ina Lefering, Giorgio Dall'Olmo, Plymouth Marine Laboratory (PML), Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Strathclyde [Glasgow], School of Marine Sciences, University of Maine, Observatoire océanologique de Villefranche-sur-mer (OOVM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Plymouth Marine Laboratory

Subjects
010504 meteorology & atmospheric sciences, Resolution (mass spectrometry), 01 natural sciences, 010309 optics, Optics, Spectrophotometry, 0103 physical sciences, Dissolved organic carbon, ddc:551, medicine, Range (statistics), 14. Life underwater, Absorption (electromagnetic radiation), Independent data, Atlantic Ocean, QC, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, medicine.diagnostic_test, business.industry, chromophoric dissolved organic matter, Atomic and Molecular Physics, and Optics, 13. Climate action, Attenuation coefficient, Ultrapure water, autonomous measurements, business
Abstract

Measurements of the absorption coefficient of chromophoric dissolved organic matter (a(y)) are needed to validate existing ocean-color algorithms. In the surface open ocean, these measurements are challenging because of low a(y) values. Yet, existing global datasets demonstrate that a(y) could contribute between 30% to 50% of the total absorption budget in the 400-450 nm spectral range, thus making accurate measurement of ay essential to constrain these uncertainties. In this study, we present a simple way of determining ay using a commercially-available insitu spectrophotometer operated in underway mode. The obtained a(y) values were validated using independent collocated measurements. The method is simple to implement, can provide measurements with very high spatio-temporal resolution, and has an accuracy of about0.0004 m(-1) and a precision of about 0.0025 m(-1) when compared to independent data (at 440 nm). The only limitation for using this method at sea is that it relies on the availability of relatively large volumes of ultrapure water. Despite this limitation, the method can deliver the a(y) data needed for validating and assessing uncertainties in ocean-colour algorithms. (C) 2017 Optical Society of America

Published
2017
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4. A Novel Near-Real-Time Quality-Control Procedure for Radiometric Profiles Measured by Bio-Argo Floats: Protocols and Performances

Author

Annick Bricaud, Catherine Schmechtig, Hervé Claustre, Antoine Poteau, Louis Marie Prieur, Xiaogang Xing, Fabrizio D'Ortenzio, Giorgio Dall'Olmo, Emanuele Organelli, Vincenzo Vellucci, Plymouth Marine Laboratory (PML), Laboratoire d'océanographie de Villefranche (LOV), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire océanologique de Villefranche-sur-mer (OOVM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire des sciences de l'univers Ecce Terra [Paris] (OSU ECCE TERRA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Oregon State University (OSU), Plymouth Marine Laboratory, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Observatoire des sciences de l'univers Ecce Terra [Paris] (ECCE TERRA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Observatoire des sciences de l'univers Ecce Terra (ECCE TERRA)

Subjects
0106 biological sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, 010604 marine biology & hydrobiology, Irradiance, Ocean Engineering, radiometry, Noon, 01 natural sciences, Signal, quality-control, Quality (physics), Almost Every Day, Environmental science, Radiometric dating, 14. Life underwater, argo, Argo, 0105 earth and related environmental sciences, Remote sensing, Communication channel
Abstract

An array of Bio-Argo floats equipped with radiometric sensors has been recently deployed in various open ocean areas representative of the diversity of trophic and bio-optical conditions prevailing in the so-called case 1 waters. Around solar noon and almost every day, each float acquires 0–250-m vertical profiles of photosynthetically available radiation and downward irradiance at three wavelengths (380, 412, and 490 nm). Up until now, more than 6500 profiles for each radiometric channel have been acquired. As these radiometric data are collected out of an operator’s control and regardless of meteorological conditions, specific and automatic data processing protocols have to be developed. This paper presents a data quality-control procedure aimed at verifying profile shapes and providing near-real-time data distribution. This procedure is specifically developed to 1) identify main issues of measurements (i.e., dark signal, atmospheric clouds, spikes, and wave-focusing occurrences) and 2) validate the final data with a hierarchy of tests to ensure a scientific utilization. The procedure, adapted to each of the four radiometric channels, is designed to flag each profile in a way compliant with the data management procedure used by the Argo program. Main perturbations in the light field are identified by the new protocols with good performances over the whole dataset. This highlights its potential applicability at the global scale. Finally, the comparison with modeled surface irradiances allows for assessing the accuracy of quality-controlled measured irradiance values and identifying any possible evolution over the float lifetime due to biofouling and instrumental drift.

Published
2016
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5. Characterization of the bio-optical anomaly and diurnal variability of particulate matter, as seen from scattering and backscattering coefficients, in ultra-oligotrophic eddies of the Mediterranean Sea

Author

R. Mauriac, Y. Combet, David Dessailly, Thierry Moutin, Giorgio Dall'Olmo, Karine Leblanc, Mireille Pujo-Pay, Hubert Loisel, Xavier Mériaux, M. Kheireddine, Josephine Ras, Vincent Vantrepotte, K. Norkvist, Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 ( LOG ), Université de Lille-Université du Littoral Côte d'Opale-Centre National de la Recherche Scientifique ( CNRS ), Institut méditerranéen d'océanologie ( MIO ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Toulon ( UTLN ) -Aix Marseille Université ( AMU ) -Institut de Recherche pour le Développement ( IRD ), Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord]), Laboratoire d'océanographie de Villefranche (LOV), Observatoire océanologique de Villefranche-sur-mer (OOVM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Océanographie Microbienne (LOMIC), Observatoire océanologique de Banyuls (OOB), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Océanographie Physique et Biogéochimique (LOPB), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de la Mer de Villefranche (IMEV), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN)

Subjects
0106 biological sciences, [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, 010504 meteorology & atmospheric sciences, lcsh:Life, EASTERN ENGLISH-CHANNEL, Atmospheric sciences, CASE-I WATERS, 01 natural sciences, DIEL VARIATIONS, Water column, Mediterranean sea, lcsh:QH540-549.5, Phytoplankton, ORGANIC-CARBON CONCENTRATION, 14. Life underwater, Ecology, Evolution, Behavior and Systematics, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Earth-Surface Processes, BEAM ATTENUATION, INHERENT OPTICAL-PROPERTIES, 010604 marine biology & hydrobiology, Attenuation, lcsh:QE1-996.5, EQUATORIAL PACIFIC, Particulates, SOUTH-PACIFIC OCEAN, LIGHT-SCATTERING, lcsh:Geology, Colored dissolved organic matter, lcsh:QH501-531, 13. Climate action, Ocean color, Climatology, Attenuation coefficient, CHLOROPHYLL-A, Environmental science, lcsh:Ecology
Abstract

The variability of inherent optical properties is investigated in the ultra-oligotrophic waters of the Mediterranean Sea sampled during the BOUM experiment performed during early summer 2008. Bio-optical relationships found for ultra-oligotrophic waters of the three anticyclonic gyres sampled significantly depart from the mean standard relationships provided for the global ocean, confirming the peculiar character of these Mediterranean waters. These optical anomalies are diversely related to the specific biological and environmental conditions occurring in the studied ecosystem. Specifically, the surface specific phytoplankton absorption coefficient exhibits values lower than those expected from the general relationships mainly in relation with a high contribution of relatively large sized phytoplankton. Conversely, the particulate backscattering coefficient, bbp, values are much higher than the mean standard values for a given chlorophyll-a concentration, TChl-a. This feature can presumably be related to the relevant influence of highly refractive submicrometer particles of Saharan origin in the surface layer of the water column. The present measurements also show that the Mediterranean Sea is greener than TChl-a alone indicates, as already stressed in previous studies. This color anomaly is partly explained by the estimated colored dissolved organic matter and submicrometer particles absorption coefficients, and to a greater extent by the high bbp/TChl-a values assuming that these particles backscatter light similarly in the green and blue parts of the visible spectrum. The diel variation of both the particulate matter attenuation and backscattering coefficients were also investigated specifically. Despite some differences in the timing and the magnitude of the daily oscillations found for these optical parameters, potential for the backscattering coefficient daily oscillation to be used, similarly to that for the attenuation coefficient, as a proxy for estimating carbon community production budget has been highlighted for the first time. This result is particularly relevant for present and future geostationary spatial ocean color missions.

Published
2011
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6. Coherence of particulate beam attenuation and backscattering coefficients in diverse open ocean environments

Author

Thierry Moutin, Toby K. Westberry, Michael J. Behrenfeld, Giorgio Dall'Olmo, Emmanuel Boss, Oregon State University (OSU), University of Maine, Laboratoire d'Océanographie Physique et Biogéochimique (LOPB), and Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Chlorophyll, 010504 meteorology & atmospheric sciences, Forward scatter, Environment, 01 natural sciences, 010309 optics, Optics, 0103 physical sciences, Scattering, Radiation, 14. Life underwater, Atlantic Ocean, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Physics, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Pacific Ocean, business.industry, Scattering, Attenuation, Pelagic zone, Particulates, Atomic and Molecular Physics, and Optics, 13. Climate action, Ocean color, Attenuation coefficient, Phytoplankton, Linear Models, Particulate Matter, business, Coherence (physics)
Abstract

We present an extensive data set of particle attenuation (c(p)), backscattering (b(bp)), and chlorophyll concentration (Chl) from a diverse set of open ocean environments. A consistent observation in the data set is the strong coherence between c(p) and b(bp) and the resulting constancy of the backscattering ratio (0.010 +/- 0.002). The strong covariability between c(p) and b(bp) must be rooted in one or both of two explanations, 1) the size distribution of particles in the ocean is remarkably conserved and particle types responsible for c(p) and b(bp) covary, 2) the same particle types exert influence on both quantities. Therefore, existing relationships between c(p) or Chl:c(p) and phytoplankton biomass and physiological indices can be conceptually extended to the use of b(bp). This finding lends support to use of satellite-derived Chl and b(bp) for investigation of phytoplankton biomass and physiology and broadens the applications of existing ocean color retrievals.

Published
2010
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