Articles | Volume 18, issue 23
https://doi.org/10.5194/bg-18-6167-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-6167-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Simultaneous assessment of oxygen- and nitrate-based net community production in a temperate shelf sea from a single ocean glider
Centre for Ocean and Atmospheric Sciences, University of East Anglia, Norwich, UK
Centre for Environment, Fisheries and Aquaculture Science, Lowestoft, UK
Naomi Greenwood
Centre for Ocean and Atmospheric Sciences, University of East Anglia, Norwich, UK
Centre for Environment, Fisheries and Aquaculture Science, Lowestoft, UK
Antony Birchill
School of Geography, Earth and Environmental Sciences, University of Plymouth, Plymouth, UK
National Oceanography Centre, Southampton, UK
Alexander Beaton
National Oceanography Centre, Southampton, UK
Matthew Palmer
National Oceanography Centre, Southampton, UK
Jan Kaiser
Centre for Ocean and Atmospheric Sciences, University of East Anglia, Norwich, UK
Related authors
Benjamin R. Loveday, Timothy Smyth, Anıl Akpinar, Tom Hull, Mark E. Inall, Jan Kaiser, Bastien Y. Queste, Matt Tobermann, Charlotte A. J. Williams, and Matthew R. Palmer
Earth Syst. Sci. Data, 14, 3997–4016, https://doi.org/10.5194/essd-14-3997-2022, https://doi.org/10.5194/essd-14-3997-2022, 2022
Short summary
Short summary
Using a new approach to combine autonomous underwater glider data and satellite Earth observations, we have generated a 19-month time series of North Sea net primary productivity – the rate at which phytoplankton absorbs carbon dioxide minus that lost through respiration. This time series, which spans 13 gliders, allows for new investigations into small-scale, high-frequency variability in the biogeochemical processes that underpin the carbon cycle and coastal marine ecosystems in shelf seas.
Tom Hull, Naomi Greenwood, Jan Kaiser, and Martin Johnson
Biogeosciences, 13, 943–959, https://doi.org/10.5194/bg-13-943-2016, https://doi.org/10.5194/bg-13-943-2016, 2016
Short summary
Short summary
We explore the estimation of NCP using an oxygen time series from a surface mooring located in the River Thames plume. Our study site is identified as a region of net heterotrophy with strong seasonal variability. Short-term daily variability in oxygen and horizontal advection is demonstrated to make accurate estimates challenging. The effects of bubble-induced supersaturation is shown to have a large influence on cumulative annual estimates.
Charlotte Williams, Tom Hull, Matthew Palmer, Claire Mahaffey, Naomi Greenwood, Jan Kaiser, and Matthew Toberman
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-100, https://doi.org/10.5194/bg-2023-100, 2023
Revised manuscript accepted for BG
Short summary
Short summary
Oxygen (O2) is a key indicator of ocean health. The risk of O2 loss in the productive coastal/continental slope regions is increasing. Autonomous underwater vehicles equipped with O2 optodes provide lots of data, but have problems resolving strong vertical O2 changes. Here we show how to overcome this and calculate how much O2 is supplied to the low-O2 bottom waters via mixing. Bursts in mixing supply nearly all of the O2 to bottom waters in autumn, stopping them reach ecologically low levels.
Amelia M. H. Bond, Markus M. Frey, Jan Kaiser, Jörg Kleffmann, Anna E. Jones, and Freya A. Squires
Atmos. Chem. Phys., 23, 5533–5550, https://doi.org/10.5194/acp-23-5533-2023, https://doi.org/10.5194/acp-23-5533-2023, 2023
Short summary
Short summary
Atmospheric nitrous acid (HONO) amount fractions measured at Halley Research Station, Antarctica, were found to be low. Vertical fluxes of HONO from the snow were also measured and agree with the estimated HONO production rate from photolysis of snow nitrate. In a simple box model of HONO sources and sinks, there was good agreement between the measured flux and amount fraction. HONO was found to be an important OH radical source at Halley.
Benjamin R. Loveday, Timothy Smyth, Anıl Akpinar, Tom Hull, Mark E. Inall, Jan Kaiser, Bastien Y. Queste, Matt Tobermann, Charlotte A. J. Williams, and Matthew R. Palmer
Earth Syst. Sci. Data, 14, 3997–4016, https://doi.org/10.5194/essd-14-3997-2022, https://doi.org/10.5194/essd-14-3997-2022, 2022
Short summary
Short summary
Using a new approach to combine autonomous underwater glider data and satellite Earth observations, we have generated a 19-month time series of North Sea net primary productivity – the rate at which phytoplankton absorbs carbon dioxide minus that lost through respiration. This time series, which spans 13 gliders, allows for new investigations into small-scale, high-frequency variability in the biogeochemical processes that underpin the carbon cycle and coastal marine ecosystems in shelf seas.
Michael P. Hemming, Jan Kaiser, Jacqueline Boutin, Liliane Merlivat, Karen J. Heywood, Dorothee C. E. Bakker, Gareth A. Lee, Marcos Cobas García, David Antoine, and Kiminori Shitashima
Ocean Sci., 18, 1245–1262, https://doi.org/10.5194/os-18-1245-2022, https://doi.org/10.5194/os-18-1245-2022, 2022
Short summary
Short summary
An underwater glider mission was carried out in spring 2016 near a mooring in the northwestern Mediterranean Sea. The glider deployment served as a test of a prototype ion-sensitive field-effect transistor pH sensor. Mean net community production rates were estimated from glider and buoy measurements of dissolved oxygen and inorganic carbon concentrations before and during the spring bloom. Incorporating advection is important for accurate mass budgets. Unexpected metabolic quotients were found.
Josué Bock, Jan Kaiser, Max Thomas, Andreas Bott, and Roland von Glasow
Geosci. Model Dev., 15, 5807–5828, https://doi.org/10.5194/gmd-15-5807-2022, https://doi.org/10.5194/gmd-15-5807-2022, 2022
Short summary
Short summary
MISTRA-v9.0 is an atmospheric boundary layer chemistry model. The model includes a detailed particle description with regards to the microphysics, gas–particle interactions, and liquid phase chemistry within particles. Version 9.0 is the first release of MISTRA as an open-source community model. This paper presents a thorough description of the model characteristics and components. We show some examples of simulations reproducing previous studies with MISTRA with good consistency.
Max Thomas, Johannes C. Laube, Jan Kaiser, Samuel Allin, Patricia Martinerie, Robert Mulvaney, Anna Ridley, Thomas Röckmann, William T. Sturges, and Emmanuel Witrant
Atmos. Chem. Phys., 21, 6857–6873, https://doi.org/10.5194/acp-21-6857-2021, https://doi.org/10.5194/acp-21-6857-2021, 2021
Short summary
Short summary
CFC gases are destroying the Earth's life-protecting ozone layer. We improve understanding of CFC destruction by measuring the isotopic fingerprint of the carbon in the three most abundant CFCs. These are the first such measurements in the main region where CFCs are destroyed – the stratosphere. We reconstruct the atmospheric isotope histories of these CFCs back to the 1950s by measuring air extracted from deep snow and using a model. The model and the measurements are generally consistent.
Luca Possenti, Ingunn Skjelvan, Dariia Atamanchuk, Anders Tengberg, Matthew P. Humphreys, Socratis Loucaides, Liam Fernand, and Jan Kaiser
Ocean Sci., 17, 593–614, https://doi.org/10.5194/os-17-593-2021, https://doi.org/10.5194/os-17-593-2021, 2021
Short summary
Short summary
A Seaglider was deployed for 8 months in the Norwegian Sea mounting an oxygen and, for the first time, a CO2 optode and a chlorophyll fluorescence sensor. The oxygen and CO2 data were used to assess the spatial and temporal variability and calculate the net community production, N(O2) and N(CT). The dataset was used to calculate net community production from inventory changes, air–sea flux, diapycnal mixing and entrainment.
Max Thomas, James France, Odile Crabeck, Benjamin Hall, Verena Hof, Dirk Notz, Tokoloho Rampai, Leif Riemenschneider, Oliver John Tooth, Mathilde Tranter, and Jan Kaiser
Atmos. Meas. Tech., 14, 1833–1849, https://doi.org/10.5194/amt-14-1833-2021, https://doi.org/10.5194/amt-14-1833-2021, 2021
Short summary
Short summary
We describe the Roland von Glasow Air-Sea-Ice Chamber, a laboratory facility for studying ocean–sea-ice–atmosphere interactions. We characterise the technical capabilities of our facility to help future users plan and perform experiments. We also characterise the sea ice grown in the facility, showing that the extinction of photosynthetically active radiation, the bulk salinity, and the growth rate of our artificial sea ice are within the range of natural values.
Reiner Onken, Heinz-Volker Fiekas, Laurent Beguery, Ines Borrione, Andreas Funk, Michael Hemming, Jaime Hernandez-Lasheras, Karen J. Heywood, Jan Kaiser, Michaela Knoll, Baptiste Mourre, Paolo Oddo, Pierre-Marie Poulain, Bastien Y. Queste, Aniello Russo, Kiminori Shitashima, Martin Siderius, and Elizabeth Thorp Küsel
Ocean Sci., 14, 321–335, https://doi.org/10.5194/os-14-321-2018, https://doi.org/10.5194/os-14-321-2018, 2018
Short summary
Short summary
In June 2014, high-resolution oceanographic data were collected in the
western Mediterranean Sea by two research vessels, 11 gliders, moored
instruments, drifters, and one profiling float. The objective
of this article is to provide an overview of the data set which
is utilised by various ongoing studies, focusing on (i) water masses and circulation, (ii) operational forecasting, (iii) data assimilation, (iv) variability of the ocean, and (v) new payloads
for gliders.
Chris J. Curtis, Jan Kaiser, Alina Marca, N. John Anderson, Gavin Simpson, Vivienne Jones, and Erika Whiteford
Biogeosciences, 15, 529–550, https://doi.org/10.5194/bg-15-529-2018, https://doi.org/10.5194/bg-15-529-2018, 2018
Short summary
Short summary
Few studies have investigated the atmospheric deposition of nitrate in the Arctic or its impacts on Arctic ecosystems. We collected late-season snowpack from three regions in western Greenland from the coast to the edge of the ice sheet. We found major differences in nitrate concentrations (lower at the coast) and deposition load (higher). Nitrate in snowpack undergoes losses and isotopic enrichment which are greatest in inland areas; hence deposition impacts may be greatest at the coast.
Michaela Knoll, Ines Borrione, Heinz-Volker Fiekas, Andreas Funk, Michael P. Hemming, Jan Kaiser, Reiner Onken, Bastien Queste, and Aniello Russo
Ocean Sci., 13, 889–904, https://doi.org/10.5194/os-13-889-2017, https://doi.org/10.5194/os-13-889-2017, 2017
Short summary
Short summary
The hydrography and circulation west of Sardinia, observed in June 2014 during REP14-MED by means of various measuring platforms, are presented and compared with previous knowledge. So far, the circulation of this area is not well-known and the hydrography is subject to long-term changes. The different water masses are characterized and temporal changes are emphasized. The observed eddies are specified and geostrophic transports in the upper ocean are presented.
Michael P. Hemming, Jan Kaiser, Karen J. Heywood, Dorothee C.E. Bakker, Jacqueline Boutin, Kiminori Shitashima, Gareth Lee, Oliver Legge, and Reiner Onken
Ocean Sci., 13, 427–442, https://doi.org/10.5194/os-13-427-2017, https://doi.org/10.5194/os-13-427-2017, 2017
Short summary
Short summary
Underwater gliders are useful platforms for monitoring the world oceans at a high resolution. An experimental pH sensor was attached to an underwater glider in the Mediterranean Sea, which is an important carbon sink region. Comparing measurements from the glider with those obtained from a ship indicated that there were issues with the experimental pH sensor. Correcting for these issues enabled us to look at pH variability in the area related to biomass abundance and physical water properties.
Markella Prokopiou, Patricia Martinerie, Célia J. Sapart, Emmanuel Witrant, Guillaume Monteil, Kentaro Ishijima, Sophie Bernard, Jan Kaiser, Ingeborg Levin, Thomas Blunier, David Etheridge, Ed Dlugokencky, Roderik S. W. van de Wal, and Thomas Röckmann
Atmos. Chem. Phys., 17, 4539–4564, https://doi.org/10.5194/acp-17-4539-2017, https://doi.org/10.5194/acp-17-4539-2017, 2017
Short summary
Short summary
Nitrous oxide is the third most important anthropogenic greenhouse gas with an increasing mole fraction. To understand its natural and anthropogenic sources
we employ isotope measurements. Results show that while the N2O mole fraction increases, its heavy isotope content decreases. The isotopic changes observed underline the dominance of agricultural emissions especially at the early part of the record, whereas in the later decades the contribution from other anthropogenic sources increases.
Imke Grefe, Sophie Fielding, Karen J. Heywood, and Jan Kaiser
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-73, https://doi.org/10.5194/bg-2017-73, 2017
Revised manuscript not accepted
Dorothee C. E. Bakker, Benjamin Pfeil, Camilla S. Landa, Nicolas Metzl, Kevin M. O'Brien, Are Olsen, Karl Smith, Cathy Cosca, Sumiko Harasawa, Stephen D. Jones, Shin-ichiro Nakaoka, Yukihiro Nojiri, Ute Schuster, Tobias Steinhoff, Colm Sweeney, Taro Takahashi, Bronte Tilbrook, Chisato Wada, Rik Wanninkhof, Simone R. Alin, Carlos F. Balestrini, Leticia Barbero, Nicholas R. Bates, Alejandro A. Bianchi, Frédéric Bonou, Jacqueline Boutin, Yann Bozec, Eugene F. Burger, Wei-Jun Cai, Robert D. Castle, Liqi Chen, Melissa Chierici, Kim Currie, Wiley Evans, Charles Featherstone, Richard A. Feely, Agneta Fransson, Catherine Goyet, Naomi Greenwood, Luke Gregor, Steven Hankin, Nick J. Hardman-Mountford, Jérôme Harlay, Judith Hauck, Mario Hoppema, Matthew P. Humphreys, Christopher W. Hunt, Betty Huss, J. Severino P. Ibánhez, Truls Johannessen, Ralph Keeling, Vassilis Kitidis, Arne Körtzinger, Alex Kozyr, Evangelia Krasakopoulou, Akira Kuwata, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Claire Lo Monaco, Ansley Manke, Jeremy T. Mathis, Liliane Merlivat, Frank J. Millero, Pedro M. S. Monteiro, David R. Munro, Akihiko Murata, Timothy Newberger, Abdirahman M. Omar, Tsuneo Ono, Kristina Paterson, David Pearce, Denis Pierrot, Lisa L. Robbins, Shu Saito, Joe Salisbury, Reiner Schlitzer, Bernd Schneider, Roland Schweitzer, Rainer Sieger, Ingunn Skjelvan, Kevin F. Sullivan, Stewart C. Sutherland, Adrienne J. Sutton, Kazuaki Tadokoro, Maciej Telszewski, Matthias Tuma, Steven M. A. C. van Heuven, Doug Vandemark, Brian Ward, Andrew J. Watson, and Suqing Xu
Earth Syst. Sci. Data, 8, 383–413, https://doi.org/10.5194/essd-8-383-2016, https://doi.org/10.5194/essd-8-383-2016, 2016
Short summary
Short summary
Version 3 of the Surface Ocean CO2 Atlas (www.socat.info) has 14.5 million CO2 (carbon dioxide) values for the years 1957 to 2014 covering the global oceans and coastal seas. Version 3 is an update to version 2 with a longer record and 44 % more CO2 values. The CO2 measurements have been made on ships, fixed moorings and drifting buoys. SOCAT enables quantification of the ocean carbon sink and ocean acidification, as well as model evaluation, thus informing climate negotiations.
Johan van der Molen, Piet Ruardij, and Naomi Greenwood
Biogeosciences, 13, 2593–2609, https://doi.org/10.5194/bg-13-2593-2016, https://doi.org/10.5194/bg-13-2593-2016, 2016
Short summary
Short summary
The potential large-scale (> 100 km) effects of marine renewable tidal energy generation in the Pentland Firth were studied using a 3-D hydrodynamics–biogeochemistry model. A realistic 800 MW scenario suggested minor effects on tides and biogeochemistry. A massive-expansion 8 GW scenario suggested effects over hundreds of kilometres away with changes of up to 10 % in tidal and ecosystem variables, the latter through clearer waters and increased primary production with associated increases in fauna.
Fabian Große, Naomi Greenwood, Markus Kreus, Hermann-Josef Lenhart, Detlev Machoczek, Johannes Pätsch, Lesley Salt, and Helmuth Thomas
Biogeosciences, 13, 2511–2535, https://doi.org/10.5194/bg-13-2511-2016, https://doi.org/10.5194/bg-13-2511-2016, 2016
Short summary
Short summary
We used the ECOHAM5 model to provide a consistent picture of the physical and biological drivers of oxygen deficiency in the North Sea. Regions susceptible to oxygen deficiency are characterised by low tidal mixing and moderate water depth (~ 40 m). Variations in upper layer productivity drive the year-to-year variability of bottom oxygen conditions. The model-based analysis reveals that benthic and pelagic remineralisation account for 90 % of bottom oxygen consumption observed at North Dogger.
Dominika Lewicka-Szczebak, Jens Dyckmans, Jan Kaiser, Alina Marca, Jürgen Augustin, and Reinhard Well
Biogeosciences, 13, 1129–1144, https://doi.org/10.5194/bg-13-1129-2016, https://doi.org/10.5194/bg-13-1129-2016, 2016
Short summary
Short summary
Oxygen isotopic signatures of N2O are formed in complex multistep enzymatic reactions and depend on isotopic fractionation during enzymatic reduction of nitrate to N2O and on the oxygen isotope exchange with soil water. We propose a new method for quantification of oxygen isotope exchange, with simultaneous determination of oxygen isotopic signatures, to decipher the mechanism of oxygen isotopic fractionation. We indicate the differences between fractionation mechanisms by various pathways.
Tom Hull, Naomi Greenwood, Jan Kaiser, and Martin Johnson
Biogeosciences, 13, 943–959, https://doi.org/10.5194/bg-13-943-2016, https://doi.org/10.5194/bg-13-943-2016, 2016
Short summary
Short summary
We explore the estimation of NCP using an oxygen time series from a surface mooring located in the River Thames plume. Our study site is identified as a region of net heterotrophy with strong seasonal variability. Short-term daily variability in oxygen and horizontal advection is demonstrated to make accurate estimates challenging. The effects of bubble-induced supersaturation is shown to have a large influence on cumulative annual estimates.
S. Walter, A. Kock, T. Steinhoff, B. Fiedler, P. Fietzek, J. Kaiser, M. Krol, M. E. Popa, Q. Chen, T. Tanhua, and T. Röckmann
Biogeosciences, 13, 323–340, https://doi.org/10.5194/bg-13-323-2016, https://doi.org/10.5194/bg-13-323-2016, 2016
Short summary
Short summary
Oceans are a source of H2, an indirect greenhouse gas. Measurements constraining the temporal and spatial patterns of oceanic H2 emissions are sparse and although H2 is assumed to be produced mainly biologically, direct evidence for biogenic marine production was lacking. By analyzing the H2 isotopic composition (δD) we were able to constrain the global H2 budget in more detail, verify biogenic production and point to additional sources. We also showed that current models are reasonably working.
J. Gloël, C. Robinson, G. H. Tilstone, G. Tarran, and J. Kaiser
Ocean Sci., 11, 947–952, https://doi.org/10.5194/os-11-947-2015, https://doi.org/10.5194/os-11-947-2015, 2015
Short summary
Short summary
We assess benzalkonium chloride (BAC) as alternative to mercuric chloride (HgCl2) for preservation of seawater samples. BAC concentrations of 50mg dm–3 inhibited microbial activity for at least 3 days in samples tested with chlorophyll a concentrations up to 1mg m–3. With fewer risks to health and environment, and lower waste disposal costs, BAC could be a short-term alternative to HgCl2, but cannot replace it for oxygen triple isotope samples, which require storage over weeks to months.
K. Ishijima, M. Takigawa, K. Sudo, S. Toyoda, N. Yoshida, T. Röckmann, J. Kaiser, S. Aoki, S. Morimoto, S. Sugawara, and T. Nakazawa
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-19947-2015, https://doi.org/10.5194/acpd-15-19947-2015, 2015
Revised manuscript not accepted
Short summary
Short summary
We developed an atmospheric N2O isotopocule model based on a chemistry-coupled atmospheric general circulation model and a simple method to optimize the model, and estimated the isotopic signatures of surface sources at the hemispheric scale. Data obtained from ground-based observations, measurements of firn air, and balloon and aircraft flights were used to optimize the long-term trends, interhemispheric gradients, and photolytic fractionation, respectively, in the model.
S. J. Allin, J. C. Laube, E. Witrant, J. Kaiser, E. McKenna, P. Dennis, R. Mulvaney, E. Capron, P. Martinerie, T. Röckmann, T. Blunier, J. Schwander, P. J. Fraser, R. L. Langenfelds, and W. T. Sturges
Atmos. Chem. Phys., 15, 6867–6877, https://doi.org/10.5194/acp-15-6867-2015, https://doi.org/10.5194/acp-15-6867-2015, 2015
Short summary
Short summary
Stratospheric ozone protects life on Earth from harmful UV-B radiation. Chlorofluorocarbons (CFCs) are man-made compounds which act to destroy this barrier.
This paper presents (1) the first measurements of the stratospheric δ(37Cl) of CFCs -11 and -113; (2) the first quantification of long-term trends in the tropospheric δ(37Cl) of CFCs -11, -12 and -113.
This study provides a better understanding of source and sink processes associated with these destructive compounds.
D. J. Mrozek, C. van der Veen, M. Kliphuis, J. Kaiser, A. A. Wiegel, and T. Röckmann
Atmos. Meas. Tech., 8, 811–822, https://doi.org/10.5194/amt-8-811-2015, https://doi.org/10.5194/amt-8-811-2015, 2015
Short summary
Short summary
Our analytical system is a promising tool for investigating the triple oxygen isotope composition of CO2 from stratospheric air samples of volumes 100ml and smaller. The method is designed for measuring air samples with CO2 mole fractions between 360 and 400ppm, and it is the first fully automated analytical system that uses CeO2 as the isotope exchange medium.
I. Grefe and J. Kaiser
Ocean Sci., 10, 501–512, https://doi.org/10.5194/os-10-501-2014, https://doi.org/10.5194/os-10-501-2014, 2014
K. L. Stansfield, M. R. Palmer, T. P. Rippeth, and J. H. Simpson
Ocean Sci. Discuss., https://doi.org/10.5194/osd-10-2141-2013, https://doi.org/10.5194/osd-10-2141-2013, 2013
Revised manuscript has not been submitted
V. V. Petrenko, P. Martinerie, P. Novelli, D. M. Etheridge, I. Levin, Z. Wang, T. Blunier, J. Chappellaz, J. Kaiser, P. Lang, L. P. Steele, S. Hammer, J. Mak, R. L. Langenfelds, J. Schwander, J. P. Severinghaus, E. Witrant, G. Petron, M. O. Battle, G. Forster, W. T. Sturges, J.-F. Lamarque, K. Steffen, and J. W. C. White
Atmos. Chem. Phys., 13, 7567–7585, https://doi.org/10.5194/acp-13-7567-2013, https://doi.org/10.5194/acp-13-7567-2013, 2013
K. Castro-Morales, N. Cassar, D. R. Shoosmith, and J. Kaiser
Biogeosciences, 10, 2273–2291, https://doi.org/10.5194/bg-10-2273-2013, https://doi.org/10.5194/bg-10-2273-2013, 2013
Related subject area
Biogeochemistry: Coastal Ocean
UAV approaches for improved mapping of vegetation cover and estimation of carbon storage of small saltmarshes: examples from Loch Fleet, northeast Scotland
Iron “ore” nothing: benthic iron fluxes from the oxygen-deficient Santa Barbara Basin enhance phytoplankton productivity in surface waters
Marine anoxia initiates giant sulfur-oxidizing bacterial mat proliferation and associated changes in benthic nitrogen, sulfur, and iron cycling in the Santa Barbara Basin, California Borderland
Uncertainty in the evolution of northwestern North Atlantic circulation leads to diverging biogeochemical projections
The additionality problem of ocean alkalinity enhancement
Short-term variation in pH in seawaters around coastal areas of Japan: characteristics and forcings
Revisiting the applicability and constraints of molybdenum- and uranium-based paleo redox proxies: comparing two contrasting sill fjords
Influence of a small submarine canyon on biogenic matter export flux in the lower St. Lawrence Estuary, eastern Canada
Single-celled bioturbators: benthic foraminifera mediate oxygen penetration and prokaryotic diversity in intertidal sediment
Assessing impacts of coastal warming, acidification, and deoxygenation on Pacific oyster (Crassostrea gigas) farming: a case study in the Hinase area, Okayama Prefecture, and Shizugawa Bay, Miyagi Prefecture, Japan
Seasonality and response of ocean acidification and hypoxia to major environmental anomalies in the southern Salish Sea, North America (2014–2018)
Unusual Hemiaulus Bloom Influences Ocean Productivity in Northeast U.S. Shelf Waters
Multiple nitrogen sources for primary production inferred from δ13C and δ15N in the southern Sea of Japan
Variability and drivers of carbonate chemistry at shellfish aquaculture sites in the Salish Sea, British Columbia
Influence of manganese cycling on alkalinity in the redox stratified water column of Chesapeake Bay
Estuarine flocculation dynamics of organic carbon and metals from boreal acid sulfate soils
Sea ice loss translates into major shifts in the carbonate environmental conditions in Arctic Shelf Sea
Drivers of particle sinking velocities in the Peruvian upwelling system
Vertical mixing alleviates autumnal oxygen deficiency in the central North Sea
Impacts and uncertainties of climate-induced changes in watershed inputs on estuarine hypoxia
Considerations for hypothetical carbon dioxide removal via alkalinity addition in the Amazon River watershed
Above- and Belowground Plant Mercury Dynamics in a Salt Marsh Estuary in Massachusetts, USA
High metabolism and periodic hypoxia associated with drifting macrophyte detritus in the shallow subtidal Baltic Sea
Oceanographic Processes Favoring Deoxygenation Inside Patagonian Fjords
Production and accumulation of reef framework by calcifying corals and macroalgae on a remote Indian Ocean cay
Zooplankton community succession and trophic links during a mesocosm experiment in the coastal upwelling off Callao Bay (Peru)
Temporal and spatial evolution of bottom-water hypoxia in the St Lawrence estuarine system
Significant nutrient consumption in the dark subsurface layer during a diatom bloom: a case study on Funka Bay, Hokkaido, Japan
Contrasts in dissolved, particulate, and sedimentary organic carbon from the Kolyma River to the East Siberian Shelf
Sediment quality assessment in an industrialized Greek coastal marine area (western Saronikos Gulf)
Limits and CO2 equilibration of near-coast alkalinity enhancement
Role of phosphorus in the seasonal deoxygenation of the East China Sea shelf
Interannual variability of the initiation of the phytoplankton growing period in two French coastal ecosystems
Spatio-temporal distribution, photoreactivity and environmental control of dissolved organic matter in the sea-surface microlayer of the eastern marginal seas of China
Metabolic alkalinity release from large port facilities (Hamburg, Germany) and impact on coastal carbon storage
A Numerical reassessment of the Gulf of Mexico carbon system in connection with the Mississippi River and global ocean
Observed and projected global warming pressure on coastal hypoxia
Benthic alkalinity fluxes from coastal sediments of the Baltic and North seas: comparing approaches and identifying knowledge gaps
Investigating the effect of nickel concentration on phytoplankton growth to assess potential side-effects of ocean alkalinity enhancement
Unprecedented summer hypoxia in southern Cape Cod Bay: an ecological response to regional climate change?
Interannual variabilities, long-term trends, and regulating factors of low-oxygen conditions in the coastal waters off Hong Kong
Causes of the extensive hypoxia in the Gulf of Riga in 2018
Trawling effects on biogeochemical processes are mediated by fauna in high-energy biogenic-reef-inhabited coastal sediments
Drought recorded by Ba∕Ca in coastal benthic foraminifera
A nitrate budget of the Bohai Sea based on an isotope mass balance model
Suspended particulate matter drives the spatial segregation of nitrogen turnover along the hyper-turbid Ems estuary
Marine CO2 system variability along the northeast Pacific Inside Passage determined from an Alaskan ferry
Reviews and syntheses: Spatial and temporal patterns in seagrass metabolic fluxes
Mixed layer depth dominates over upwelling in regulating the seasonality of ecosystem functioning in the Peruvian upwelling system
Temporal dynamics of surface ocean carbonate chemistry in response to natural and simulated upwelling events during the 2017 coastal El Niño near Callao, Peru
William Hiles, Lucy C. Miller, Craig Smeaton, and William E. N. Austin
Biogeosciences, 21, 929–948, https://doi.org/10.5194/bg-21-929-2024, https://doi.org/10.5194/bg-21-929-2024, 2024
Short summary
Short summary
Saltmarsh soils may help to limit the rate of climate change by storing carbon. To understand their impacts, they must be accurately mapped. We use drone data to estimate the size of three saltmarshes in NE Scotland. We find that drone imagery, combined with tidal data, can reliably inform our understanding of saltmarsh size. When compared with previous work using vegetation communities, we find that our most reliable new estimates of stored carbon are 15–20 % smaller than previously estimated.
De'Marcus Robinson, Anh L. D. Pham, David J. Yousavich, Felix Janssen, Frank Wenzhöfer, Eleanor C. Arrington, Kelsey M. Gosselin, Marco Sandoval-Belmar, Matthew Mar, David L. Valentine, Daniele Bianchi, and Tina Treude
Biogeosciences, 21, 773–788, https://doi.org/10.5194/bg-21-773-2024, https://doi.org/10.5194/bg-21-773-2024, 2024
Short summary
Short summary
The present study suggests that high release of ferrous iron from the seafloor of the oxygen-deficient Santa Barabara Basin (California) supports surface primary productivity, creating positive feedback on seafloor iron release by enhancing low-oxygen conditions in the basin.
David J. Yousavich, De'Marcus Robinson, Xuefeng Peng, Sebastian J. E. Krause, Frank Wenzhöfer, Felix Janssen, Na Liu, Jonathan Tarn, Franklin Kinnaman, David L. Valentine, and Tina Treude
Biogeosciences, 21, 789–809, https://doi.org/10.5194/bg-21-789-2024, https://doi.org/10.5194/bg-21-789-2024, 2024
Short summary
Short summary
Declining oxygen (O2) concentrations in coastal oceans can threaten people’s ways of life and food supplies. Here, we investigate how mats of bacteria that proliferate on the seafloor of the Santa Barbara Basin sustain and potentially worsen these O2 depletion events through their unique chemoautotrophic metabolism. Our study shows how changes in seafloor microbiology and geochemistry brought on by declining O2 concentrations can help these mats grow as well as how that growth affects the basin.
Krysten Rutherford, Katja Fennel, Lina Garcia Suarez, and Jasmin G. John
Biogeosciences, 21, 301–314, https://doi.org/10.5194/bg-21-301-2024, https://doi.org/10.5194/bg-21-301-2024, 2024
Short summary
Short summary
We downscaled two mid-century (~2075) ocean model projections to a high-resolution regional ocean model of the northwest North Atlantic (NA) shelf. In one projection, the NA shelf break current practically disappears; in the other it remains almost unchanged. This leads to a wide range of possible future shelf properties. More accurate projections of coastal circulation features would narrow the range of possible outcomes of biogeochemical projections for shelf regions.
Lennart Thomas Bach
Biogeosciences, 21, 261–277, https://doi.org/10.5194/bg-21-261-2024, https://doi.org/10.5194/bg-21-261-2024, 2024
Short summary
Short summary
Ocean alkalinity enhancement (OAE) is a widely considered marine carbon dioxide removal method. OAE aims to accelerate chemical rock weathering, which is a natural process that slowly sequesters atmospheric carbon dioxide. This study shows that the addition of anthropogenic alkalinity via OAE can reduce the natural release of alkalinity and, therefore, reduce the efficiency of OAE for climate mitigation. However, the additionality problem could be mitigated via a variety of activities.
Tsuneo Ono, Daisuke Muraoka, Masahiro Hayashi, Makiko Yorifuji, Akihiro Dazai, Shigeyuki Omoto, Takehiro Tanaka, Tomohiro Okamura, Goh Onitsuka, Kenji Sudo, Masahiko Fujii, Ryuji Hamanoue, and Masahide Wakita
Biogeosciences, 21, 177–199, https://doi.org/10.5194/bg-21-177-2024, https://doi.org/10.5194/bg-21-177-2024, 2024
Short summary
Short summary
We carried out parallel year-round observations of pH and related parameters in five stations around the Japan coast. It was found that short-term acidified situations with Omega_ar less than 1.5 occurred at four of five stations. Most of such short-term acidified events were related to the short-term low salinity event, and the extent of short-term pH drawdown at high freshwater input was positively correlated with the nutrient concentration of the main rivers that flow into the coastal area.
K. Mareike Paul, Martijn Hermans, Sami A. Jokinen, Inda Brinkmann, Helena L. Filipsson, and Tom Jilbert
Biogeosciences, 20, 5003–5028, https://doi.org/10.5194/bg-20-5003-2023, https://doi.org/10.5194/bg-20-5003-2023, 2023
Short summary
Short summary
Seawater naturally contains trace metals such as Mo and U, which accumulate under low oxygen conditions on the seafloor. Previous studies have used sediment Mo and U contents as an archive of changing oxygen concentrations in coastal waters. Here we show that in fjords the use of Mo and U for this purpose may be impaired by additional processes. Our findings have implications for the reliable use of Mo and U to reconstruct oxygen changes in fjords.
Hannah Sharpe, Michel Gosselin, Catherine Lalande, Alexandre Normandeau, Jean-Carlos Montero-Serrano, Khouloud Baccara, Daniel Bourgault, Owen Sherwood, and Audrey Limoges
Biogeosciences, 20, 4981–5001, https://doi.org/10.5194/bg-20-4981-2023, https://doi.org/10.5194/bg-20-4981-2023, 2023
Short summary
Short summary
We studied the impact of submarine canyon processes within the Pointe-des-Monts system on biogenic matter export and phytoplankton assemblages. Using data from three oceanographic moorings, we show that the canyon experienced two low-amplitude sediment remobilization events in 2020–2021 that led to enhanced particle fluxes in the deep-water column layer > 2.6 km offshore. Sinking phytoplankton fluxes were lower near the canyon compared to background values from the lower St. Lawrence Estuary.
Dewi Langlet, Florian Mermillod-Blondin, Noémie Deldicq, Arthur Bauville, Gwendoline Duong, Lara Konecny, Mylène Hugoni, Lionel Denis, and Vincent M. P. Bouchet
Biogeosciences, 20, 4875–4891, https://doi.org/10.5194/bg-20-4875-2023, https://doi.org/10.5194/bg-20-4875-2023, 2023
Short summary
Short summary
Benthic foraminifera are single-cell marine organisms which can move in the sediment column. They were previously reported to horizontally and vertically transport sediment particles, yet the impact of their motion on the dissolved fluxes remains unknown. Using microprofiling, we show here that foraminiferal burrow formation increases the oxygen penetration depth in the sediment, leading to a change in the structure of the prokaryotic community.
Masahiko Fujii, Ryuji Hamanoue, Lawrence Patrick Cases Bernardo, Tsuneo Ono, Akihiro Dazai, Shigeyuki Oomoto, Masahide Wakita, and Takehiro Tanaka
Biogeosciences, 20, 4527–4549, https://doi.org/10.5194/bg-20-4527-2023, https://doi.org/10.5194/bg-20-4527-2023, 2023
Short summary
Short summary
This is the first study of the current and future impacts of climate change on Pacific oyster farming in Japan. Future coastal warming and acidification may affect oyster larvae as a result of longer exposure to lower-pH waters. A prolonged spawning period may harm oyster processing by shortening the shipping period and reducing oyster quality. To minimize impacts on Pacific oyster farming, in addition to mitigation measures, local adaptation measures may be required.
Simone R. Alin, Jan A. Newton, Richard A. Feely, Samantha A. Siedlecki, and Dana J. Greeley
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-181, https://doi.org/10.5194/bg-2023-181, 2023
Revised manuscript accepted for BG
Short summary
Short summary
We provide a new multi-stressor data product allowed us to characterize the seasonality of temperature, oxygen, and carbon dioxide in the southern Salish Sea and provided insight into impacts of major marine heatwave and precipitation anomalies on regional ocean acidification and hypoxia. We also described the present-day frequencies of temperature, oxygen, and ocean acidification conditions that cross thresholds of sensitive regional species that are economically or ecologically important.
S. Alejandra Castillo Cieza, Rachel H. R. Stanley, Pierre Marrec, Diana N. Fontaine, E. Taylor Crockford, Dennis J. McGillicuddy, Arshia Mehta, Susanne Menden-Deuer, Emily E. Peacock, Tatiana A. Rynearson, Zoe O. Sandwith, Weifeng Zhang, and Heidi M. Sosik
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-153, https://doi.org/10.5194/bg-2023-153, 2023
Revised manuscript accepted for BG
Short summary
Short summary
The coastal ocean in northeastern USA provides many services, including fisheries and habitat for threatened species. In summer 2019, a bloom occurred of an unusual large phytoplankton, the diatom Hemiaulus with nitrogen fixing symbionts. This led to vast changes in productivity and grazing rates in the ecosystem. This work shows that the emergence of one species can have profound effects on ecosystem function. Such changes maybe become more prevalent as the ocean warms due to climate change.
Taketoshi Kodama, Atsushi Nishimoto, Ken-ichi Nakamura, Misato Nakae, Naoki Iguchi, Yosuke Igeta, and Yoichi Kogure
Biogeosciences, 20, 3667–3682, https://doi.org/10.5194/bg-20-3667-2023, https://doi.org/10.5194/bg-20-3667-2023, 2023
Short summary
Short summary
Carbon and nitrogen are essential elements for organisms; their stable isotope ratios (13C : 12C, 15N : 14N) are useful tools for understanding turnover and movement in the ocean. In the Sea of Japan, the environment is rapidly being altered by human activities. The 13C : 12C of small organic particles is increased by active carbon fixation, and phytoplankton growth increases the values. The 15N : 14N variations suggest that nitrates from many sources contribute to organic production.
Eleanor Simpson, Debby Ianson, Karen Elizabeth Kohfeld, Ana C. Franco, Paul A. Covert, Marty Davelaar, and Yves Perreault
EGUsphere, https://doi.org/10.5194/egusphere-2023-1553, https://doi.org/10.5194/egusphere-2023-1553, 2023
Short summary
Short summary
Shellfish aquaculture operates in nearshore areas where data on key ocean acidification (OA) parameters is limited. We show daily and seasonal variability in chemical properties at nearshore aquaculture sites in Canada and define drivers of these changes. Nearshore locations have greater variability than open waters and uptake of carbon by phytoplankton is the major driver of variability. Areas with high primary productivity are recommended for aquaculture as they will be less vulnerable to OA.
Aubin Thibault de Chanvalon, George W. Luther, Emily R. Estes, Jennifer Necker, Bradley M. Tebo, Jianzhong Su, and Wei-Jun Cai
Biogeosciences, 20, 3053–3071, https://doi.org/10.5194/bg-20-3053-2023, https://doi.org/10.5194/bg-20-3053-2023, 2023
Short summary
Short summary
The intensity of the oceanic trap of CO2 released by anthropogenic activities depends on the alkalinity brought by continental weathering. Between ocean and continent, coastal water and estuaries can limit or favour the alkalinity transfer. This study investigate new interactions between dissolved metals and alkalinity in the oxygen-depleted zone of estuaries.
Joonas J. Virtasalo, Peter Österholm, and Eero Asmala
Biogeosciences, 20, 2883–2901, https://doi.org/10.5194/bg-20-2883-2023, https://doi.org/10.5194/bg-20-2883-2023, 2023
Short summary
Short summary
We mixed acidic metal-rich river water from acid sulfate soils and seawater in the laboratory to study the flocculation of dissolved metals and organic matter in estuaries. Al and Fe flocculated already at a salinity of 0–2 to large organic flocs (>80 µm size). Precipitation of Al and Fe hydroxide flocculi (median size 11 µm) began when pH exceeded ca. 5.5. Mn transferred weakly to Mn hydroxides and Co to the flocs. Up to 50 % of Cu was associated with the flocs, irrespective of seawater mixing.
Claudine Hauri, Brita Irving, Sam Dupont, Remi Pages, Donna Hauser, and Seth Danielson
EGUsphere, https://doi.org/10.5194/egusphere-2023-1386, https://doi.org/10.5194/egusphere-2023-1386, 2023
Short summary
Short summary
Arctic marine ecosystems are highly susceptible to impacts of climate change and ocean acidification. We present pH and pCO2 time-series (2016–2020) from the Chukchi Ecosystem Observatory and analyze the drivers of the current conditions to get a better understanding of how climate change and ocean acidification could affect the ecological niches of organisms.
Moritz Baumann, Allanah Joy Paul, Jan Taucher, Lennart Thomas Bach, Silvan Goldenberg, Paul Stange, Fabrizio Minutolo, and Ulf Riebesell
Biogeosciences, 20, 2595–2612, https://doi.org/10.5194/bg-20-2595-2023, https://doi.org/10.5194/bg-20-2595-2023, 2023
Short summary
Short summary
The sinking velocity of marine particles affects how much atmospheric CO2 is stored inside our oceans. We measured particle sinking velocities in the Peruvian upwelling system and assessed their physical and biochemical drivers. We found that sinking velocity was mainly influenced by particle size and porosity, while ballasting minerals played only a minor role. Our findings help us to better understand the particle sinking dynamics in this highly productive marine system.
Charlotte Williams, Tom Hull, Matthew Palmer, Claire Mahaffey, Naomi Greenwood, Jan Kaiser, and Matthew Toberman
Biogeosciences Discuss., https://doi.org/10.5194/bg-2023-100, https://doi.org/10.5194/bg-2023-100, 2023
Revised manuscript accepted for BG
Short summary
Short summary
Oxygen (O2) is a key indicator of ocean health. The risk of O2 loss in the productive coastal/continental slope regions is increasing. Autonomous underwater vehicles equipped with O2 optodes provide lots of data, but have problems resolving strong vertical O2 changes. Here we show how to overcome this and calculate how much O2 is supplied to the low-O2 bottom waters via mixing. Bursts in mixing supply nearly all of the O2 to bottom waters in autumn, stopping them reach ecologically low levels.
Kyle E. Hinson, Marjorie A. M. Friedrichs, Raymond G. Najjar, Maria Herrmann, Zihao Bian, Gopal Bhatt, Pierre St-Laurent, Hanqin Tian, and Gary Shenk
Biogeosciences, 20, 1937–1961, https://doi.org/10.5194/bg-20-1937-2023, https://doi.org/10.5194/bg-20-1937-2023, 2023
Short summary
Short summary
Climate impacts are essential for environmental managers to consider when implementing nutrient reduction plans designed to reduce hypoxia. This work highlights relative sources of uncertainty in modeling regional climate impacts on the Chesapeake Bay watershed and consequent declines in bay oxygen levels. The results demonstrate that planned water quality improvement goals are capable of reducing hypoxia levels by half, offsetting climate-driven impacts on terrestrial runoff.
Linquan Mu, Jaime B. Palter, and Hongjie Wang
Biogeosciences, 20, 1963–1977, https://doi.org/10.5194/bg-20-1963-2023, https://doi.org/10.5194/bg-20-1963-2023, 2023
Short summary
Short summary
Enhancing ocean alkalinity accelerates carbon dioxide removal from the atmosphere. We hypothetically added alkalinity to the Amazon River and examined the increment of the carbon uptake by the Amazon plume. We also investigated the minimum alkalinity addition in which this perturbation at the river mouth could be detected above the natural variability.
Ting Wang, Buyun Du, Inke Forbrich, Jun Zhou, Joshua Polen, Elsie M. Sunderland, Prentiss H. Balcom, Celia Y. Chen, and Daniel Obrist
EGUsphere, https://doi.org/10.5194/egusphere-2023-720, https://doi.org/10.5194/egusphere-2023-720, 2023
Short summary
Short summary
The strong seasonal increases of Hg in aboveground biomass during the growing season and the lack of changes observed after senescence in this salt marsh ecosystem suggest physiologically controlled Hg uptake pathways. The Hg sources found in marsh aboveground tissues originate from a mix of sources, unlike terrestrial ecosystems where atmospheric GEM is the main source. While belowground plant tissues mostly take up Hg from soils. Overall, the salt marsh currently serves as a small net Hg sink.
Karl M. Attard, Anna Lyssenko, and Iván F. Rodil
Biogeosciences, 20, 1713–1724, https://doi.org/10.5194/bg-20-1713-2023, https://doi.org/10.5194/bg-20-1713-2023, 2023
Short summary
Short summary
Aquatic plants produce a large amount of organic matter through photosynthesis that, following erosion, is deposited on the seafloor. In this study, we show that plant detritus can trigger low-oxygen conditions (hypoxia) in shallow coastal waters, making conditions challenging for most marine animals. We propose that the occurrence of hypoxia may be underestimated because measurements typically do not consider the region closest to the seafloor, where detritus accumulates.
Pamela Linford, Iván Pérez-Santos, Paulina Montero, Patricio Díaz, Claudia Aracena, Elías Pinilla, Facundo Barrera, Manuel Castillo, Aida Alvera-Azcárate, Mónica Alvarado, Gabriel Soto, Cécile Pujol, Camila Schwerter, Sara Arenas-Uribe, Pilar Navarro, Guido Mancilla-Gutiérrez, Robinson Altamirano, Javiera San Martín, and Camila Soto-Riquelme
EGUsphere, https://doi.org/10.5194/egusphere-2023-706, https://doi.org/10.5194/egusphere-2023-706, 2023
Short summary
Short summary
The Patagonian fjord is one world region where low-oxygen water and hypoxia conditions is observed. An in-situ data set was used to quantify the mechanism involved in the presence of low-oxygen water and hypoxic conditions in northern Patagonian fjords. Water mass analysis confirmed the contribution of equatorial subsurface water in the advection of the low-oxygen water and hypoxic conditions occurred when the community respiration rate exceeded the gross primary production.
M. James McLaughlin, Cindy Bessey, Gary A. Kendrick, John Keesing, and Ylva S. Olsen
Biogeosciences, 20, 1011–1026, https://doi.org/10.5194/bg-20-1011-2023, https://doi.org/10.5194/bg-20-1011-2023, 2023
Short summary
Short summary
Coral reefs face increasing pressures from environmental change at present. The coral reef framework is produced by corals and calcifying algae. The Kimberley region of Western Australia has escaped land-based anthropogenic impacts. Specimens of the dominant coral and algae were collected from Browse Island's reef platform and incubated in mesocosms to measure calcification and production patterns of oxygen. This study provides important data on reef building and climate-driven effects.
Patricia Ayón Dejo, Elda Luz Pinedo Arteaga, Anna Schukat, Jan Taucher, Rainer Kiko, Helena Hauss, Sabrina Dorschner, Wilhelm Hagen, Mariona Segura-Noguera, and Silke Lischka
Biogeosciences, 20, 945–969, https://doi.org/10.5194/bg-20-945-2023, https://doi.org/10.5194/bg-20-945-2023, 2023
Short summary
Short summary
Ocean upwelling regions are highly productive. With ocean warming, severe changes in upwelling frequency and/or intensity and expansion of accompanying oxygen minimum zones are projected. In a field experiment off Peru, we investigated how different upwelling intensities affect the pelagic food web and found failed reproduction of dominant zooplankton. The changes projected could severely impact the reproductive success of zooplankton communities and the pelagic food web in upwelling regions.
Mathilde Jutras, Alfonso Mucci, Gwenaëlle Chaillou, William A. Nesbitt, and Douglas W. R. Wallace
Biogeosciences, 20, 839–849, https://doi.org/10.5194/bg-20-839-2023, https://doi.org/10.5194/bg-20-839-2023, 2023
Short summary
Short summary
The deep waters of the lower St Lawrence Estuary and gulf have, in the last decades, experienced a strong decline in their oxygen concentration. Below 65 µmol L-1, the waters are said to be hypoxic, with dire consequences for marine life. We show that the extent of the hypoxic zone shows a seven-fold increase in the last 20 years, reaching 9400 km2 in 2021. After a stable period at ~ 65 µmol L⁻¹ from 1984 to 2019, the oxygen level also suddenly decreased to ~ 35 µmol L-1 in 2020.
Sachi Umezawa, Manami Tozawa, Yuichi Nosaka, Daiki Nomura, Hiroji Onishi, Hiroto Abe, Tetsuya Takatsu, and Atsushi Ooki
Biogeosciences, 20, 421–438, https://doi.org/10.5194/bg-20-421-2023, https://doi.org/10.5194/bg-20-421-2023, 2023
Short summary
Short summary
We conducted repetitive observations in Funka Bay, Japan, during the spring bloom 2019. We found nutrient concentration decreases in the dark subsurface layer during the bloom. Incubation experiments confirmed that diatoms could consume nutrients at a substantial rate, even in darkness. We concluded that the nutrient reduction was mainly caused by nutrient consumption by diatoms in the dark.
Dirk Jong, Lisa Bröder, Tommaso Tesi, Kirsi H. Keskitalo, Nikita Zimov, Anna Davydova, Philip Pika, Negar Haghipour, Timothy I. Eglinton, and Jorien E. Vonk
Biogeosciences, 20, 271–294, https://doi.org/10.5194/bg-20-271-2023, https://doi.org/10.5194/bg-20-271-2023, 2023
Short summary
Short summary
With this study, we want to highlight the importance of studying both land and ocean together, and water and sediment together, as these systems function as a continuum, and determine how organic carbon derived from permafrost is broken down and its effect on global warming. Although on the one hand it appears that organic carbon is removed from sediments along the pathway of transport from river to ocean, it also appears to remain relatively ‘fresh’, despite this removal and its very old age.
Georgia Filippi, Manos Dassenakis, Vasiliki Paraskevopoulou, and Konstantinos Lazogiannis
Biogeosciences, 20, 163–189, https://doi.org/10.5194/bg-20-163-2023, https://doi.org/10.5194/bg-20-163-2023, 2023
Short summary
Short summary
The pollution of the western Saronikos Gulf from heavy metals has been examined through the study of marine sediment cores. It is a deep gulf (maximum depth 440 m) near Athens affected by industrial and volcanic activity. Eight cores were received from various stations and depths and analysed for their heavy metal content and geochemical characteristics. The results were evaluated by using statistical methods, environmental indicators and comparisons with old data.
Jing He and Michael D. Tyka
Biogeosciences, 20, 27–43, https://doi.org/10.5194/bg-20-27-2023, https://doi.org/10.5194/bg-20-27-2023, 2023
Short summary
Short summary
Recently, ocean alkalinity enhancement (OAE) has gained interest as a scalable way to address the urgent need for negative CO2 emissions. In this paper we examine the capacity of different coastlines to tolerate alkalinity enhancement and the time scale of CO2 uptake following the addition of a given quantity of alkalinity. The results suggest that OAE has significant potential and identify specific favorable and unfavorable coastlines for its deployment.
Arnaud Laurent, Haiyan Zhang, and Katja Fennel
Biogeosciences, 19, 5893–5910, https://doi.org/10.5194/bg-19-5893-2022, https://doi.org/10.5194/bg-19-5893-2022, 2022
Short summary
Short summary
The Changjiang is the main terrestrial source of nutrients to the East China Sea (ECS). Nutrient delivery to the ECS has been increasing since the 1960s, resulting in low oxygen (hypoxia) during phytoplankton decomposition in summer. River phosphorus (P) has increased less than nitrogen, and therefore, despite the large nutrient delivery, phytoplankton growth can be limited by the lack of P. Here, we investigate this link between P limitation, phytoplankton production/decomposition, and hypoxia.
Coline Poppeschi, Guillaume Charria, Anne Daniel, Romaric Verney, Peggy Rimmelin-Maury, Michaël Retho, Eric Goberville, Emilie Grossteffan, and Martin Plus
Biogeosciences, 19, 5667–5687, https://doi.org/10.5194/bg-19-5667-2022, https://doi.org/10.5194/bg-19-5667-2022, 2022
Short summary
Short summary
This paper aims to understand interannual changes in the initiation of the phytoplankton growing period (IPGP) in the current context of global climate changes over the last 20 years. An important variability in the timing of the IPGP is observed with a trend towards a later IPGP during this last decade. The role and the impact of extreme events (cold spells, floods, and wind burst) on the IPGP is also detailed.
Lin Yang, Jing Zhang, Anja Engel, and Gui-Peng Yang
Biogeosciences, 19, 5251–5268, https://doi.org/10.5194/bg-19-5251-2022, https://doi.org/10.5194/bg-19-5251-2022, 2022
Short summary
Short summary
Enrichment factors of dissolved organic matter (DOM) in the eastern marginal seas of China exhibited a significant spatio-temporal variation. Photochemical and enrichment processes co-regulated DOM enrichment in the sea-surface microlayer (SML). Autochthonous DOM was more frequently enriched in the SML than terrestrial DOM. DOM in the sub-surface water exhibited higher aromaticity than that in the SML.
Mona Norbisrath, Johannes Pätsch, Kirstin Dähnke, Tina Sanders, Gesa Schulz, Justus E. E. van Beusekom, and Helmuth Thomas
Biogeosciences, 19, 5151–5165, https://doi.org/10.5194/bg-19-5151-2022, https://doi.org/10.5194/bg-19-5151-2022, 2022
Short summary
Short summary
Total alkalinity (TA) regulates the oceanic storage capacity of atmospheric CO2. TA is also metabolically generated in estuaries and influences coastal carbon storage through its inflows. We used water samples and identified the Hamburg port area as the one with highest TA generation. Of the overall riverine TA load, 14 % is generated within the estuary. Using a biogeochemical model, we estimated potential effects on the coastal carbon storage under possible anthropogenic and climate changes.
Le Zhang and Z. George Xue
Biogeosciences, 19, 4589–4618, https://doi.org/10.5194/bg-19-4589-2022, https://doi.org/10.5194/bg-19-4589-2022, 2022
Short summary
Short summary
We adopt a high-resolution carbon model for the Gulf of Mexico (GoM) and calculate the decadal trends of important carbon system variables in the GoM from 2001 to 2019. The GoM surface CO2 values experienced a steady increase over the past 2 decades, and the ocean surface pH is declining. Although carbonate saturation rates remain supersaturated with aragonite, they show a slightly decreasing trend. The northern GoM is a stronger carbon sink than we thought.
Michael M. Whitney
Biogeosciences, 19, 4479–4497, https://doi.org/10.5194/bg-19-4479-2022, https://doi.org/10.5194/bg-19-4479-2022, 2022
Short summary
Short summary
Coastal hypoxia is a major environmental problem of increasing severity. The 21st-century projections analyzed indicate global coastal waters will warm and experience rapid declines in oxygen. The forecasted median coastal trends for increasing sea surface temperature and decreasing oxygen capacity are 48 % and 18 % faster than the rates observed over the last 4 decades. Existing hypoxic areas are expected to worsen, and new hypoxic areas likely will emerge under these warming-related pressures.
Bryce Van Dam, Nele Lehmann, Mary A. Zeller, Andreas Neumann, Daniel Pröfrock, Marko Lipka, Helmuth Thomas, and Michael Ernst Böttcher
Biogeosciences, 19, 3775–3789, https://doi.org/10.5194/bg-19-3775-2022, https://doi.org/10.5194/bg-19-3775-2022, 2022
Short summary
Short summary
We quantified sediment–water exchange at shallow sites in the North and Baltic seas. We found that porewater irrigation rates in the former were approximately twice as high as previously estimated, likely driven by relatively high bioirrigative activity. In contrast, we found small net fluxes of alkalinity, ranging from −35 µmol m−2 h−1 (uptake) to 53 µmol m−2 h−1 (release). We attribute this to low net denitrification, carbonate mineral (re-)precipitation, and sulfide (re-)oxidation.
Jiaying Abby Guo, Robert Strzepek, Anusuya Willis, Aaron Ferderer, and Lennart Thomas Bach
Biogeosciences, 19, 3683–3697, https://doi.org/10.5194/bg-19-3683-2022, https://doi.org/10.5194/bg-19-3683-2022, 2022
Short summary
Short summary
Ocean alkalinity enhancement is a CO2 removal method with significant potential, but it can lead to a perturbation of the ocean with trace metals such as nickel. This study tested the effect of increasing nickel concentrations on phytoplankton growth and photosynthesis. We found that the response to nickel varied across the 11 phytoplankton species tested here, but the majority were rather insensitive. We note, however, that responses may be different under other experimental conditions.
Malcolm E. Scully, W. Rockwell Geyer, David Borkman, Tracy L. Pugh, Amy Costa, and Owen C. Nichols
Biogeosciences, 19, 3523–3536, https://doi.org/10.5194/bg-19-3523-2022, https://doi.org/10.5194/bg-19-3523-2022, 2022
Short summary
Short summary
For two consecutive summers, the bottom waters in southern Cape Cod Bay became severely depleted of dissolved oxygen. Low oxygen levels in bottom waters have never been reported in this area before, and this unprecedented occurrence is likely the result of a new algae species that recently began blooming during the late-summer months. We present data suggesting that blooms of this new species are the result of regional climate change including warmer waters and changes in summer winds.
Zheng Chen, Bin Wang, Chuang Xu, Zhongren Zhang, Shiyu Li, and Jiatang Hu
Biogeosciences, 19, 3469–3490, https://doi.org/10.5194/bg-19-3469-2022, https://doi.org/10.5194/bg-19-3469-2022, 2022
Short summary
Short summary
Deterioration of low-oxygen conditions in the coastal waters off Hong Kong was revealed by monitoring data over two decades. The declining wind forcing and the increasing nutrient input contributed significantly to the areal expansion and intense deterioration of low-oxygen conditions. Also, the exacerbated eutrophication drove a shift in the dominant source of organic matter from terrestrial inputs to in situ primary production, which has probably led to an earlier onset of hypoxia in summer.
Stella-Theresa Stoicescu, Jaan Laanemets, Taavi Liblik, Māris Skudra, Oliver Samlas, Inga Lips, and Urmas Lips
Biogeosciences, 19, 2903–2920, https://doi.org/10.5194/bg-19-2903-2022, https://doi.org/10.5194/bg-19-2903-2022, 2022
Short summary
Short summary
Coastal basins with high input of nutrients often suffer from oxygen deficiency. In summer 2018, the extent of oxygen depletion was exceptional in the Gulf of Riga. We analyzed observational data and found that extensive oxygen deficiency appeared since the water layer close to the seabed, where oxygen is consumed, was separated from the surface layer. The problem worsens if similar conditions restricting vertical transport of oxygen occur more frequently in the future.
Justin C. Tiano, Jochen Depestele, Gert Van Hoey, João Fernandes, Pieter van Rijswijk, and Karline Soetaert
Biogeosciences, 19, 2583–2598, https://doi.org/10.5194/bg-19-2583-2022, https://doi.org/10.5194/bg-19-2583-2022, 2022
Short summary
Short summary
This study gives an assessment of bottom trawling on physical, chemical, and biological characteristics in a location known for its strong currents and variable habitats. Although trawl gears only removed the top 1 cm of the seabed surface, impacts on reef-building tubeworms significantly decreased carbon and nutrient cycling. Lighter trawls slightly reduced the impact on fauna and nutrients. Tubeworms were strongly linked to biogeochemical and faunal aspects before but not after trawling.
Inda Brinkmann, Christine Barras, Tom Jilbert, Tomas Næraa, K. Mareike Paul, Magali Schweizer, and Helena L. Filipsson
Biogeosciences, 19, 2523–2535, https://doi.org/10.5194/bg-19-2523-2022, https://doi.org/10.5194/bg-19-2523-2022, 2022
Short summary
Short summary
The concentration of the trace metal barium (Ba) in coastal seawater is a function of continental input, such as riverine discharge. Our geochemical records of the severely hot and dry year 2018, and following wet year 2019, reveal that prolonged drought imprints with exceptionally low Ba concentrations in benthic foraminiferal calcium carbonates of coastal sediments. This highlights the potential of benthic Ba / Ca to trace past climate extremes and variability in coastal marine records.
Shichao Tian, Birgit Gaye, Jianhui Tang, Yongming Luo, Wenguo Li, Niko Lahajnar, Kirstin Dähnke, Tina Sanders, Tianqi Xiong, Weidong Zhai, and Kay-Christian Emeis
Biogeosciences, 19, 2397–2415, https://doi.org/10.5194/bg-19-2397-2022, https://doi.org/10.5194/bg-19-2397-2022, 2022
Short summary
Short summary
We constrain the nitrogen budget and in particular the internal sources and sinks of nitrate in the Bohai Sea by using a mass-based and dual stable isotope approach based on δ15N and δ18O of nitrate. Based on available mass fluxes and isotope data an updated nitrogen budget is proposed. Compared to previous estimates, it is more complete and includes the impact of the interior cycle (nitrification) on the nitrate pool. The main external nitrogen sources are rivers contributing 19.2 %–25.6 %.
Gesa Schulz, Tina Sanders, Justus E. E. van Beusekom, Yoana G. Voynova, Andreas Schöl, and Kirstin Dähnke
Biogeosciences, 19, 2007–2024, https://doi.org/10.5194/bg-19-2007-2022, https://doi.org/10.5194/bg-19-2007-2022, 2022
Short summary
Short summary
Estuaries can significantly alter nutrient loads before reaching coastal waters. Our study of the heavily managed Ems estuary (Northern Germany) reveals three zones of nitrogen turnover along the estuary with water-column denitrification in the most upstream hyper-turbid part, nitrate production in the middle reaches and mixing/nitrate uptake in the North Sea. Suspended particulate matter was the overarching control on nitrogen cycling in the hyper-turbid estuary.
Wiley Evans, Geoffrey T. Lebon, Christen D. Harrington, Yuichiro Takeshita, and Allison Bidlack
Biogeosciences, 19, 1277–1301, https://doi.org/10.5194/bg-19-1277-2022, https://doi.org/10.5194/bg-19-1277-2022, 2022
Short summary
Short summary
Information on the marine carbon dioxide system along the northeast Pacific Inside Passage has been limited. To address this gap, we instrumented an Alaskan ferry in order to characterize the marine carbon dioxide system in this region. Data over a 2-year period were used to assess drivers of the observed variability, identify the timing of severe conditions, and assess the extent of contemporary ocean acidification as well as future levels consistent with a 1.5 °C warmer climate.
Melissa Ward, Tye L. Kindinger, Heidi K. Hirsh, Tessa M. Hill, Brittany M. Jellison, Sarah Lummis, Emily B. Rivest, George G. Waldbusser, Brian Gaylord, and Kristy J. Kroeker
Biogeosciences, 19, 689–699, https://doi.org/10.5194/bg-19-689-2022, https://doi.org/10.5194/bg-19-689-2022, 2022
Short summary
Short summary
Here, we synthesize the results from 62 studies reporting in situ rates of seagrass metabolism to highlight spatial and temporal variability in oxygen fluxes and inform efforts to use seagrass to mitigate ocean acidification. Our analyses suggest seagrass meadows are generally autotrophic and variable in space and time, and the effects on seawater oxygen are relatively small in magnitude.
Tianfei Xue, Ivy Frenger, A. E. Friederike Prowe, Yonss Saranga José, and Andreas Oschlies
Biogeosciences, 19, 455–475, https://doi.org/10.5194/bg-19-455-2022, https://doi.org/10.5194/bg-19-455-2022, 2022
Short summary
Short summary
The Peruvian system supports 10 % of the world's fishing yield. In the Peruvian system, wind and earth’s rotation bring cold, nutrient-rich water to the surface and allow phytoplankton to grow. But observations show that it grows worse at high upwelling. Using a model, we find that high upwelling happens when air mixes the water the most. Then phytoplankton is diluted and grows slowly due to low light and cool upwelled water. This study helps to estimate how it might change in a warming climate.
Shao-Min Chen, Ulf Riebesell, Kai G. Schulz, Elisabeth von der Esch, Eric P. Achterberg, and Lennart T. Bach
Biogeosciences, 19, 295–312, https://doi.org/10.5194/bg-19-295-2022, https://doi.org/10.5194/bg-19-295-2022, 2022
Short summary
Short summary
Oxygen minimum zones in the ocean are characterized by enhanced carbon dioxide (CO2) levels and are being further acidified by increasing anthropogenic atmospheric CO2. Here we report CO2 system measurements in a mesocosm study offshore Peru during a rare coastal El Niño event to investigate how CO2 dynamics may respond to ongoing ocean deoxygenation. Our observations show that nitrogen limitation, productivity, and plankton community shift play an important role in driving the CO2 dynamics.
Cited articles
Alkire, M. B., D'Asaro, E., Lee, C., Jane Perry, M., Gray, A., Cetinić, I.,
Briggs, N., Rehm, E., Kallin, E., Kaiser, J., and González-Posada, A.:
Estimates of Net Community Production and Export Using High-Resolution,
Lagrangian Measurements of O2, NO3−, and POC through the
Evolution of a Spring Diatom Bloom in the North Atlantic, Deep-Sea
Res. Pt. I, 64, 157–174,
2012. a, b, c, d, e
Alkire, M. B., Lee, C. M., a. D'Asaro, E., Perry, M. J., Briggs, N. T.,
Cetinić, I., and Gray, A. M.: Net Community Production and Export from
Seaglider Measurements in the North Atlantic after the Spring Bloom,
J. Geophys. Res.-Ocean., 119, 6121–6139,
https://doi.org/10.1002/2014jc010105, 2014. a
Anderson, L. A. and Sarmiento, J. L.: Redfield Ratios of Remineralization
Determined by Nutrient Data Analysis, Global Biogeochem. Cy., 8,
65–80, https://doi.org/10.1029/93gb03318, 1994. a
Barone, B., Nicholson, D., Ferrón, S., Firing, E., and Karl, D.: The
Estimation of Gross Oxygen Production and Community Respiration from
Autonomous Time-series Measurements in the Oligotrophic Ocean, Limnol.
Oceanogr.-Method., 17, lom3.10340, https://doi.org/10.1002/lom3.10340, 2019. a
Bauer, J. E., Cai, W.-J., Raymond, P. A., Bianchi, T. S., Hopkinson, C. S., and
Regnier, P. A. G.: The Changing Carbon Cycle of the Coastal Ocean, Nature,
504, 61–70, https://doi.org/10.1038/nature12857, 2013. a, b
Beaton, A. D., Cardwell, C. L., Thomas, R. S., Sieben, V. J., Legiret, F.-E.,
Waugh, E. M., Statham, P. J., Mowlem, M. C., and Morgan, H.: Lab-on-Chip
Measurement of Nitrate and Nitrite for In Situ Analysis of
Natural Waters, Environ. Sci. Technol., 46, 9548–9556,
https://doi.org/10.1021/es300419u, 2012. a, b, c
Binetti, U., Kaiser, J., Damerell, G. M., Rumyantseva, A., Martin, A. P.,
Henson, S., and Heywood, K. J.: Net Community Oxygen Production Derived from
Seaglider Deployments at the Porcupine Abyssal Plain Site (PAP;
Northeast Atlantic) in 2012–13, Prog. Oceanogr., 183,
102293, https://doi.org/10.1016/j.pocean.2020.102293, 2020. a
Birchill, A., Beaton, A. D., Pascal, R. W., Hull, T., and Kaiser, J.: An
Alternative Framework to Assess Marine Ecosystem Functioning in
Shelf Seas (AlterEco) Post-Recovery Seaglider Lab-on-a-Chip
(LoC) Nitrate + Nitrite (NOx) Data between November 2017 and
April 2019 in the North Sea, BODC [data set],
https://doi.org/10/f984, 2021. a, b
Bittig, H. C., Körtzinger, A., Neill, C., van Ooijen, E., Plant, J. N.,
Hahn, J., Johnson, K. S., Yang, B., and Emerson, S. R.: Oxygen Optode
Sensors: Principle, Characterization, Calibration, and
Application in the Ocean, Front. Mar. Sci., 4, 1–25,
https://doi.org/10.3389/fmars.2017.00429, 2018. a, b, c
Bozec, Y., Thomas, H., Elkalay, K., and De Baar, H. J.: The Continental Shelf
Pump for CO2 in the North Sea – Evidence from Summer
Observation, Mar. Chem., 93, 131–147,
https://doi.org/10.1016/j.marchem.2004.07.006, 2005. a
Bozec, Y., Thomas, H., Schiettecatte, L.-S., Borges, A. V., Elkalay, K., and
de Baar, H. J. W.: Assessment of the Processes Controlling the Seasonal
Variations of Dissolved Inorganic Carbon in the North Sea, Limnol.
Oceanogr., 51, 2746–2762, https://doi.org/10.4319/lo.2006.51.6.2746, 2006. a, b, c
Brainerd, K. E. and Gregg, M. C.: Surface Mixed and Mixing Layer Depths, Deep-Sea Res. Pt. I, 42, 1521–1543,
https://doi.org/10.1016/0967-0637(95)00068-h, 1995. a
British Oceanographic Data Centre (BODC): https://www.bodc.ac.uk/, last access: 15 September 2021.
Burson, A., Stomp, M., Akil, L., Brussaard, C. P. D., and Huisman, J.:
Unbalanced Reduction of Nutrient Loads Has Created an Offshore Gradient from
Phosphorus to Nitrogen Limitation in the North Sea, Limnol.
Oceanogr., 61, 869–888, https://doi.org/10.1002/lno.10257, 2016. a
Bushinsky, S. M. and Emerson, S.: Marine Biological Production from in Situ
Oxygen Measurements on a Profiling Float in the Subarctic Pacific Ocean,
Global Biogeochem. Cy., 29, 2050–2060, https://doi.org/10.1002/2015gb005251,
2015. a
Capuzzo, E., Lynam, C. P., Barry, J., Stephens, D., Forster, R. M., Greenwood,
N., McQuatters-Gollop, A., Silva, T., van Leeuwen, S. M., and Engelhard,
G. H.: A Decline in Primary Production in the North Sea over 25 Years,
Associated with Reductions in Zooplankton Abundance and Fish Stock
Recruitment, Glob. Change Biol., 24, e352–e364, https://doi.org/10.1111/gcb.13916,
2018. a, b
Carpenter, B., Gelman, A., Hoffman, M. D., Lee, D., Goodrich, B., Betancourt, M., Brubaker, M., Guo, J., Li, P., and Riddell, A.: Stan : A Probabilistic Programming Language, 76, 1–32,
https://doi.org/10.18637/jss.v076.i01, 2017. a
Castro-Morales, K. and Kaiser, J.: Using Dissolved Oxygen Concentrations to
Determine Mixed Layer Depths in the Bellingshausen Sea, Ocean Sci., 8,
1–10, https://doi.org/10.5194/os-8-1-2012, 2012. a
Cefas Data Portal: https://data.cefas.co.uk/, last access: 15 September 2021.
Copernicus, C. C. S.: ERA5: Fifth Generation of ECMWF Atmospheric
Reanalyses of the Global Climate, CDS [data set], https://doi.org/10.24381/cds.bd0915c6, 2018. a
de Boyer Montégut, C.: Mixed Layer Depth over the Global Ocean: An
Examination of Profile Data and a Profile-Based Climatology, J.
Geophys. Res., 109, C12003, https://doi.org/10.1029/2004jc002378, 2004. a
Emeis, K.-C., van Beusekom, J., Callies, U., Ebinghaus, R., Kannen, A.,
Kraus, G., Kröncke, I., Lenhart, H., Lorkowski, I., Matthias, V.,
Möllmann, C., Pätsch, J., Scharfe, M., Thomas, H., Weisse, R., and
Zorita, E.: The North Sea – A Shelf Sea in the Anthropocene,
J. Mar. Syst., 141, 18–33, https://doi.org/10.1016/j.jmarsys.2014.03.012,
2015. a, b, c, d, e
Emerson, S. and Bushinsky, S.: The Role of Bubbles during Air-Sea Gas Exchange,
J. Geophys. Res.-Ocean., 121, 4360–4376,
https://doi.org/10.1002/2016jc011744, 2016. a
Garau, B., Ruiz, S., Zhang, W. G., Pascual, A., Heslop, E., Kerfoot, J., and
Tintoré, J.: Thermal Lag Correction on Slocum CTD Glider Data,
J. Atmos. Ocean. Technol., 28, 1065–1071,
https://doi.org/10.1175/jtech-d-10-05030.1, 2011. a
Garcia, H. E. and Gordon, L. I.: Oxygen Solubility in Seawater: Better Fitting
Equations, Limnol. Oceanogr., 37, 1307–1312,
https://doi.org/10.4319/lo.1992.37.6.1307, 1992. a
GEBCO, B. C. G.: The GEBCO_2019 Grid – a Continuous Terrain Model of
the Global Oceans and Land, BODC [data set],
https://doi.org/10.5285/836F016A-33BE-6DDC-E053-6C86ABC0788E, 2019. a, b, c
Graham, J. A., O'Dea, E., Holt, J., Polton, J., Hewitt, H. T., Furner, R.,
Guihou, K., Brereton, A., Arnold, A., Wakelin, S., Castillo Sanchez, J. M.,
and Mayorga Adame, C. G.: AMM15: A New High-Resolution NEMO
Configuration for Operational Simulation of the European North-West
Shelf, Geosci. Model Dev., 11, 681–696,
https://doi.org/10.5194/gmd-11-681-2018, 2018. a
Greenwood, N.: SmartBuoy Observational Network – North Dogger, Cefas [data set],
https://doi.org/10.14466/CEFASDATAHUB.29, 2016. a
Greenwood, N., Parker, E. R., Fernand, L., Sivyer, D. B., Weston, K., Painting,
S. J., Kröger, S., Forster, R. M., Lees, H. E., Mills, D. K., and Laane,
R. W. P. M.: Detection of Low Bottom Water Oxygen Concentrations in the
North Sea; Implications for Monitoring and Assessment of Ecosystem
Health, Biogeosciences, 7, 1357–1373, https://doi.org/10.5194/bg-7-1357-2010, 2010. a
Gröger, M., Maier-Reimer, E., Mikolajewicz, U., Moll, A., and Sein, D.:
NW European Shelf under Climate Warming: Implications for Open Ocean
– Shelf Exchange, Primary Production, and Carbon Absorption,
Biogeosciences, 10, 3767–3792, https://doi.org/10.5194/bg-10-3767-2013, 2013. a
Große, F., Greenwood, N., Kreus, M., Lenhart, H.-J., Machoczek, D.,
Pätsch, J., Salt, L., and Thomas, H.: Looking beyond Stratification: A
Model-Based Analysis of the Biological Drivers of Oxygen Deficiency in the
North Sea, Biogeosciences, 13, 2511–2535, https://doi.org/10.5194/bg-13-2511-2016,
2016. a, b, c
Halpern, B. S., Longo, C., Lowndes, J. S. S., Best, B. D., Frazier, M., Katona,
S. K., Kleisner, K. M., Rosenberg, A. A., Scarborough, C., and Selig, E. R.:
Patterns and Emerging Trends in Global Ocean Health, PLOS ONE, 10,
e0117863, https://doi.org/10.1371/journal.pone.0117863, 2015. a
Harris, P. T., Macmillan-Lawler, M., Rupp, J., and Baker, E. K.:
Geomorphology of the Oceans, Mar. Geol., 352, 4–24,
https://doi.org/10.1016/j.margeo.2014.01.011, 2014. a
Hickman, A., Moore, C., Sharples, J., Lucas, M., Tilstone, G., Krivtsov, V.,
and Holligan, P.: Primary Production and Nitrate Uptake within the Seasonal
Thermocline of a Stratified Shelf Sea, Mar. Ecol. Prog. Ser., 463,
39–57, https://doi.org/10.3354/meps09836, 2012. a
Hill, A. E., Brown, J., Fernand, L., Holt, J., Horsburgh, K. J., Proctor, R.,
Raine, R., and Turrell, W. R.: Thermohaline Circulation of Shallow Tidal
Seas, Geophys. Res. Lett., 35, L11605, https://doi.org/10.1029/2008gl033459,
2008. a
Hinrichs, I., Gouretski, V., Pätsch, J., Emeis, K.-C., and Stammer, D.:
North Sea Biogeochemical Climatology (Version 1.1),
https://doi.org/10.1594/WDCC/NSBCLIM_V1.1, 2017. a
Hull, T. and Johnson, M.: Airsea: R Tools for Air-Sea Gas Exchange Studies
(0.2), Cefas, https://doi.org/10.5281/zenodo.45656, 2015. a
Hull, T. and Kaiser, J.: AlterEco Post-Recovery Seaglider Data between
November 2017 and April 2019 in the North Sea, BODC [data set], https://doi.org/10/fk8m,
2020. a
Hull, T., Greenwood, N., Kaiser, J., and Johnson, M.: Uncertainty and
Sensitivity in Optode-Based Shelf-Sea Net Community Production Estimates,
Biogeosciences, 13, 943–959, https://doi.org/10.5194/bg-13-943-2016, 2016. a, b, c, d
Hull, T., Johnson, M., Greenwood, N., and Kaiser, J.: Bottom Mixed Layer Oxygen
Dynamics in the Celtic Sea, Biogeochemistry, 149, 263–289, 2020. a
Johnson, K. S., Coletti, L. J., and Chavez, F. P.: Diel Nitrate Cycles Observed
with in Situ Sensors Predict Monthly and Annual New Production, Deep-Sea
Res. Pt. I, 53, 561–573,
https://doi.org/10.1016/j.dsr.2005.12.004, 2006. a
Johnson, M. T.: A Numerical Scheme to Calculate Temperature and Salinity
Dependent Air-Water Transfer Velocities for Any Gas, Ocean Sci., 6,
913–932, https://doi.org/10.5194/os-6-913-2010, 2010. a
Kara, A. B., Rochford, P. A., and Hurlburt, H. E.: An Optimal Definition for
Ocean Mixed Layer Depth, J. Geophys. Res.-Ocean., 105,
16803–16821, https://doi.org/10.1029/2000jc900072, 2000. a
Kitidis, V., Shutler, J. D., Ashton, I., Warren, M., Brown, I., Findlay, H.,
Hartman, S. E., Sanders, R., Humphreys, M., Kivimäe, C., Greenwood, N.,
Hull, T., Pearce, D., McGrath, T., Stewart, B. M., Walsham, P., McGovern, E.,
Bozec, Y., Gac, J.-P., van Heuven, S. M. A. C., Hoppema, M., Schuster, U.,
Johannessen, T., Omar, A., Lauvset, S. K., Skjelvan, I., Olsen, A.,
Steinhoff, T., Körtzinger, A., Becker, M., Lefevre, N., Diverrès, D.,
Gkritzalis, T., Cattrijsse, A., Petersen, W., Voynova, Y. G., Chapron, B.,
Grouazel, A., Land, P. E., Sharples, J., and Nightingale, P. D.: Winter
Weather Controls Net Influx of Atmospheric CO2 on the North-West
European Shelf, Sci. Rep., 9, 20153, https://doi.org/10/gg5sc5, 2019. a
Legge, O., Johnson, M., Hicks, N., Jickells, T., Diesing, M., Aldridge, J.,
Andrews, J., Artioli, Y., Bakker, D. C. E., Burrows, M. T., Carr, N., Cripps,
G., Felgate, S. L., Fernand, L., Greenwood, N., Hartman, S., Kröger, S.,
Lessin, G., Mahaffey, C., Mayor, D. J., Parker, R., Queirós, A. M.,
Shutler, J. D., Silva, T., Stahl, H., Tinker, J., Underwood, G. J. C., Van
Der Molen, J., Wakelin, S., Weston, K., and Williamson, P.: Carbon on the
Northwest European Shelf: Contemporary Budget and Future
Influences, Front. Mar. Sci., 7, 143, https://doi.org/10.3389/fmars.2020.00143,
2020. a
Li, Y.-H. and Peng, T.-H.: Latitudinal Change of Remineralization Ratios in the
Oceans and Its Implication for Nutrient Cycles, Global Biogeochem. Cy.,
16, 77-1–77-16, https://doi.org/10.1029/2001gb001828, 2002. a, b
Liang, J.-H., Deutsch, C., McWilliams, J. C., Baschek, B., Sullivan, P. P., and
Chiba, D.: Parameterizing Bubble-Mediated Air-Sea Gas Exchange and Its Effect
on Ocean Ventilation, Global Biogeochem. Cy., 27, 894–905,
https://doi.org/10.1002/gbc.20080, 2013. a, b
Liang, J.-H., Emerson, S. R., D'Asaro, E. A., McNeil, C. L., Harcourt, R. R.,
Sullivan, P. P., Yang, B., and Cronin, M. F.: On the Role of Sea-State in
Bubble-Mediated Air-Sea Gas Flux during a Winter Storm, J.
Geophys. Res.-Ocean., 122, 2671–2685, https://doi.org/10.1002/2016jc012408,
2017. a
Mathis, M., Elizalde, A., Mikolajewicz, U., and Pohlmann, T.: Variability
Patterns of the General Circulation and Sea Water Temperature in the North
Sea, Prog. Oceanogr., 135, 91–112,
https://doi.org/10.1016/j.pocean.2015.04.009, 2015. a
Nightingale, P. D., Malin, G., Law, C. S., Watson, A. J., Liss, P. S.,
Liddicoat, M. I., Boutin, J., and Upstill-Goddard, R. C.: In Situ Evaluation
of Air-Sea Gas Exchange Parameterizations Using Novel Conservative and
Volatile Tracers, Global Biogeochem. Cy., 14, 373–387,
https://doi.org/10.1029/1999gb900091, 2000. a
Palevsky, H. I., Ribalet, F., Swalwell, J. E., Cosca, C. E., Cokelet, E. D.,
Feely, R. A., Armbrust, E. V., and Quay, P. D.: The Influence of Net
Community Production and Phytoplankton Community Structure on CO2 Uptake in the Gulf of Alaska: Gulf of Alaska
NCP, Phytoplankton, and CO2, Global
Biogeochem. Cy., 27, 664–676, https://doi.org/10.1002/gbc.20058, 2013. a
Plant, J. N., Johnson, K. S., Sakamoto, C. M., Jannasch, H. W., Coletti, L. J.,
Riser, S. C., and Swift, D. D.: Net Community Production at Ocean Station
Papa Observed with Nitrate and Oxygen Sensors on Profiling Floats, Global
Biogeochem. Cy., 30, 859–879, https://doi.org/10.1002/2015gb005349, 2016. a, b
Plumeridge, A. A. and Roberts, C. M.: Conservation Targets in Marine Protected
Area Management Suffer from Shifting Baseline Syndrome: A Case Study on the
Dogger Bank, Mar. Pollut. Bull., 116, 395–404,
2017. a
Queste, B.: Hydrographic Observations of Oxygen and Related Physical Variables
in the North Sea and Western Ross Sea Polynya, University of East Anglia, UK, 2013. a
Queste, B. Y., Fernand, L., Jickells, T. D., and Heywood, K. J.: Spatial Extent
and Historical Context of North Sea Oxygen Depletion in August 2010,
Biogeochemistry, 113, 53–68, 2013. a
Richardson, K. and Pedersen, F. B.: Estimation of New Production in the North
Sea: Consequences for Temporal and Spatial Variability of Phytoplankton,
ICES J. Mar. Sci., 55, 574–580, https://doi.org/10.1006/jmsc.1998.0402,
1998. a, b
Riegman, R., Malschaert, H., and Colijn, F.: Primary Production of
Phytoplankton at a Frontal Zone Located at the Northern Slope of the Dogger
Bank (North Sea), Mar. Biol., 105, 329–336,
https://doi.org/10.1007/bf01344303, 1990. a
Rovelli, L., Dengler, M., Schmidt, M., Sommer, S., Linke, P., and McGinnis,
D. F.: Thermocline Mixing and Vertical Oxygen Fluxes in the Stratified
Central North Sea, Biogeosciences, 13, 1609–1620,
https://doi.org/10.5194/bg-13-1609-2016, 2016.
a, b, c
Sharples, J., Mayor, D. J., Poulton, A. J., Rees, A. P., and Robinson, C.:
Shelf Sea Biogeochemistry: Nutrient and Carbon Cycling in a Temperate
Shelf Sea Water Column, Prog. Oceanogr., 177, 102182,
https://doi.org/10.1016/j.pocean.2019.102182, 2019. a
Tengberg, A. and Hovdenes, J.: Information on Long-Term Stability and Accuracy
of Aanderaa Oxygen Optodes. Information about Multipoint Calibration
System and Sensor Option Overview., Tech. rep., Aanderaa Data Instruments,
2014. a
Thomas, H.: Enhanced Open Ocean Storage of CO2 from Shelf Sea
Pumping, Science, 304, 1005–1008, 2004. a
Thomas, H., Bozec, Y., Elkalay, K., de Baar, H. J. W., Borges, A. V., and
Schiettecatte, L.-S.: Controls of the Surface Water Partial Pressure of
CO2 in the North Sea, Biogeosciences, 2, 323–334,
https://doi.org/10.5194/bg-2-323-2005, 2005. a
Uchida, H., Kawano, T., Kaneko, I., and Fukasawa, M.: In Situ Calibration
of Optode-Based Oxygen Sensors, J. Atmos. Ocean.
Technol., 25, 2271–2281, https://doi.org/10.1175/2008jtecho549.1, 2008. a
Vincent, A. G., Pascal, R. W., Beaton, A. D., Walk, J., Hopkins, J. E.,
Woodward, E. M. S., Mowlem, M., and Lohan, M. C.: Nitrate Drawdown during a
Shelf Sea Spring Bloom Revealed Using a Novel Microfluidic in Situ Chemical
Sensor Deployed within an Autonomous Underwater Glider, Mar. Chem.,
205, 29–36, https://doi.org/10.1016/j.marchem.2018.07.005, 2018. a, b, c, d, e, f, g, h
Wakelin, S. L., Artioli, Y., Holt, J. T., Butenschön, M., and Blackford,
J.: Controls on Near-Bed Oxygen Concentration on the Northwest European
Continental Shelf under a Potential Future Climate Scenario, Prog.
Oceanogr., 187, 102400, https://doi.org/10.1016/j.pocean.2020.102400, 2020. a
Wihsgott, J. U., Sharples, J., Hopkins, J. E., Woodward, E. M. S., Hull, T.,
Greenwood, N., and Sivyer, D. B.: Observations of Vertical Mixing in Autumn
and Its Effect on the Autumn Phytoplankton Bloom, Prog. Oceanogr.,
177, 102059, https://doi.org/10.1016/j.pocean.2019.01.001, 2019. a
Short summary
The shallow shelf seas play a large role in the global cycling of CO2 and also support large fisheries. We use an autonomous underwater vehicle in the central North Sea to measure the rates of change in oxygen and nutrients.
Using these data we determine the amount of carbon dioxide taken out of the atmosphere by the sea and measure how productive the region is.
These observations will be useful for improving our predictive models and help us predict and adapt to a changing ocean.
The shallow shelf seas play a large role in the global cycling of CO2 and also support large...
Altmetrics
Final-revised paper
Preprint