Articles | Volume 12, issue 23
https://doi.org/10.5194/bg-12-6881-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-12-6881-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
02 Dec 2015
Research article |
| 02 Dec 2015
Carbonate saturation state of surface waters in the Ross Sea and Southern Ocean: controls and implications for the onset of aragonite undersaturation
H. B. DeJong
CORRESPONDING AUTHOR
Department of Earth System Science, Stanford University, Stanford, CA, USA
R. B. Dunbar
Department of Earth System Science, Stanford University, Stanford, CA, USA
D. Mucciarone
Department of Earth System Science, Stanford University, Stanford, CA, USA
D. A. Koweek
Department of Earth System Science, Stanford University, Stanford, CA, USA
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Riss M. Kell, Adam V. Subhas, Nicole L. Schanke, Lauren E. Lees, Rebecca J. Chmiel, Deepa Rao, Margaret M. Brisbin, Dawn M. Moran, Matthew R. McIlvin, Francesco Bolinesi, Olga Mangoni, Raffaella Casotti, Cecilia Balestra, Tristan Horner, Robert B. Dunbar, Andrew E. Allen, Giacomo R. DiTullio, and Mak A. Saito
EGUsphere, https://doi.org/10.1101/2023.11.05.565706, https://doi.org/10.1101/2023.11.05.565706, 2025
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Photosynthetic productivity is strongly influenced by water column nutrient availability. Despite the importance of zinc, definitive evidence for oceanic zinc limitation of photosynthesis has been scarce. We applied multiple biogeochemical measurements to a field site in Terra Nova Bay, Antarctica, to demonstrate that the phytoplankton community was experiencing zinc limitation. This field evidence paves the way for future experimental studies to consider Zn as a limiting oceanic micronutrient.
Riss M. Kell, Rebecca J. Chmiel, Deepa Rao, Dawn M. Moran, Matthew R. McIlvin, Tristan J. Horner, Nicole L. Schanke, Ichiko Sugiyama, Robert B. Dunbar, Giacomo R. DiTullio, and Mak A. Saito
Biogeosciences, 21, 5685–5706, https://doi.org/10.5194/bg-21-5685-2024, https://doi.org/10.5194/bg-21-5685-2024, 2024
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Despite interest in modeling the biogeochemical uptake and cycling of the trace metal zinc (Zn), measurements of Zn uptake in natural marine phytoplankton communities have not been conducted previously. To fill this gap, we employed a stable isotope uptake rate measurement method to quantify Zn uptake into natural phytoplankton assemblages within the Southern Ocean. Zn demand was high and rapid enough to depress the inventory of Zn available to phytoplankton on seasonal timescales.
Andrew N. Hennig, David A. Mucciarone, Stanley S. Jacobs, Richard A. Mortlock, and Robert B. Dunbar
The Cryosphere, 18, 791–818, https://doi.org/10.5194/tc-18-791-2024, https://doi.org/10.5194/tc-18-791-2024, 2024
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A total of 937 seawater paired oxygen isotope (δ18O)–salinity samples collected during seven cruises on the SE Amundsen Sea between 1994 and 2020 reveal a deep freshwater source with δ18O − 29.4±1.0‰, consistent with the signature of local ice shelf melt. Local mean meteoric water content – comprised primarily of glacial meltwater – increased between 1994 and 2020 but exhibited greater interannual variability than increasing trend.
Kate E. Ashley, Robert McKay, Johan Etourneau, Francisco J. Jimenez-Espejo, Alan Condron, Anna Albot, Xavier Crosta, Christina Riesselman, Osamu Seki, Guillaume Massé, Nicholas R. Golledge, Edward Gasson, Daniel P. Lowry, Nicholas E. Barrand, Katelyn Johnson, Nancy Bertler, Carlota Escutia, Robert Dunbar, and James A. Bendle
Clim. Past, 17, 1–19, https://doi.org/10.5194/cp-17-1-2021, https://doi.org/10.5194/cp-17-1-2021, 2021
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We present a multi-proxy record of Holocene glacial meltwater input, sediment transport, and sea-ice variability off East Antarctica. Our record shows that a rapid Antarctic sea-ice increase during the mid-Holocene (~ 4.5 ka) occurred against a backdrop of increasing glacial meltwater input and gradual climate warming. We suggest that mid-Holocene ice shelf cavity expansion led to cooling of surface waters and sea-ice growth, which slowed basal ice shelf melting.
David A. Koweek, Kerry J. Nickols, Paul R. Leary, Steve Y. Litvin, Tom W. Bell, Timothy Luthin, Sarah Lummis, David A. Mucciarone, and Robert B. Dunbar
Biogeosciences, 14, 31–44, https://doi.org/10.5194/bg-14-31-2017, https://doi.org/10.5194/bg-14-31-2017, 2017
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This paper presents results from a year-long study of a kelp forest offshore of Pacific Grove, California. We use tools and techniques from chemistry to study the kelp forest. We find very large chemical variability in the kelp forest, primarily between the surface of the water and the bottom of the forest. There are many reasons for this variability; we conclude that both regional upwelling and kelp growth are responsible for contributing to this variability.
Justine Kimball, Robert Eagle, and Robert Dunbar
Biogeosciences, 13, 6487–6505, https://doi.org/10.5194/bg-13-6487-2016, https://doi.org/10.5194/bg-13-6487-2016, 2016
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Deep-sea corals are a potentially valuable archive of temperature and ocean chemistry. We analyzed clumped isotope signatures (Δ47) in live-collected aragonitic scleractinian and high-Mg calcitic gorgonian deep-sea corals and compared results to published data and found offsets between taxa. The observed patterns in deep-sea corals may record distinct mineral equilibrium signatures due to very slow growth rates, kinetic isotope effects, and/or variable acid digestion fractionation factors.
T. P. Guilderson, M. D. McCarthy, R. B. Dunbar, A. Englebrecht, and E. B. Roark
Biogeosciences, 10, 6019–6028, https://doi.org/10.5194/bg-10-6019-2013, https://doi.org/10.5194/bg-10-6019-2013, 2013
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Biogeochemistry: Open Ocean
Marine snow morphology drives sinking and attenuation in the ocean interior
An upper-mesopelagic-zone carbon budget for the subarctic North Pacific
Ocean alkalinity enhancement in an open-ocean ecosystem: biogeochemical responses and carbon storage durability
Relationships between the concentration of particulate organic nitrogen and the inherent optical properties of seawater in oceanic surface waters
Inadequacies in the representation of sub-seasonal phytoplankton dynamics in Earth system models
Nitrogen dynamics and nitrate stable isotopes indicate nitrogen loss in the Bay of Bengal
A tracer study for the development of in-water monitoring, reporting, and verification (MRV) of ship-based ocean alkalinity enhancement
Composite model-based estimate of the ocean carbon sink from 1959 to 2022
Phytoplankton community structure in relation to iron and macronutrient fluxes from subsurface waters in the western North Pacific during summer
Intense and localized export of selected marine snow types at eddy edges in the South Atlantic Ocean
Spatial distributions of iron and manganese in surface waters of the Arctic's Laptev and East Siberian seas
Climate-driven shifts in Southern Ocean primary producers and biogeochemistry in CMIP6 models
Oceanic enrichment of ammonium and its impacts on phytoplankton community composition under a high-emissions scenario
Ocean acidification trends and carbonate system dynamics across the North Atlantic subpolar gyre water masses during 2009–2019
Pelagic coccolithophore production and dissolution and their impacts on particulate inorganic carbon cycling in the western North Pacific
From small scale variability to mesoscale stability in surface ocean pH: implications for air-sea CO2 equilibration
Sedimentary organic matter signature hints at the phytoplankton-driven biological carbon pump in the central Arabian Sea
Hydrological cycle amplification imposes spatial patterns on the climate change response of ocean pH and carbonate chemistry
Assessing the tropical Atlantic biogeochemical processes in the Norwegian Earth System Model
Evolution of oxygen and stratification and their relationship in the North Pacific Ocean in CMIP6 Earth system models
Evaluation of CMIP6 model performance in simulating historical biogeochemistry across the southern South China Sea
Drivers of decadal trends in the ocean carbon sink in the past, present, and future in Earth system models
Anthropogenic carbon storage and its decadal changes in the Atlantic between 1990–2020
Ocean alkalinity enhancement impacts: regrowth of marine microalgae in alkaline mineral concentrations simulating the initial concentrations after ship-based dispersions
Climatic controls on metabolic constraints in the ocean
Effects of grain size and seawater salinity on magnesium hydroxide dissolution and secondary calcium carbonate precipitation kinetics: implications for ocean alkalinity enhancement
Short-term response of Emiliania huxleyi growth and morphology to abrupt salinity stress
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Phosphomonoesterase and phosphodiesterase activities in the eastern Mediterranean in two contrasting seasonal situations
Net primary production annual maxima in the North Atlantic projected to shift in the 21st century
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Loss of nitrogen via anaerobic ammonium oxidation (anammox) in the California Current system during the late Quaternary
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Linking northeastern North Pacific oxygen changes to upstream surface outcrop variations
Underestimation of multi-decadal global O2 loss due to an optimal interpolation method
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Seasonal dynamics and annual budget of dissolved inorganic carbon in the northwestern Mediterranean deep-convection region
The fingerprint of climate variability on the surface ocean cycling of iron and its isotopes
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Importance of multiple sources of iron for the upper-ocean biogeochemistry over the northern Indian Ocean
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Key parameters representing the gravity flux in global models are sinking speed and vertical attenuation of exported material. We calculate, for the first time, these parameters in situ in the ocean for six intermittent blooms followed by export events using high-resolution (3 d) time series of 0–1000 m depth profiles from imaging sensors mounted on an Argo float. We show that sinking speed depends not only on size but also on the morphology of the particles, with density being an important property.
Brandon M. Stephens, Montserrat Roca-Martí, Amy E. Maas, Vinícius J. Amaral, Samantha Clevenger, Shawnee Traylor, Claudia R. Benitez-Nelson, Philip W. Boyd, Ken O. Buesseler, Craig A. Carlson, Nicolas Cassar, Margaret Estapa, Andrea J. Fassbender, Yibin Huang, Phoebe J. Lam, Olivier Marchal, Susanne Menden-Deuer, Nicola L. Paul, Alyson E. Santoro, David A. Siegel, and David P. Nicholson
Biogeosciences, 22, 3301–3328, https://doi.org/10.5194/bg-22-3301-2025, https://doi.org/10.5194/bg-22-3301-2025, 2025
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The ocean’s mesopelagic zone (MZ) plays a crucial role in the global carbon cycle. This study combines new and previously published measurements of organic carbon supply and demand collected in August 2018 in the MZ of the subarctic North Pacific Ocean. Supply was insufficient to meet demand in August, but supply entering into the MZ in the spring of 2018 could have met the August demand. Results suggest observations over seasonal timescales may help to close MZ carbon budgets.
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Biogeosciences, 22, 2749–2766, https://doi.org/10.5194/bg-22-2749-2025, https://doi.org/10.5194/bg-22-2749-2025, 2025
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Ocean alkalinity enhancement (OAE) is being assessed for its potential to absorb atmospheric CO2 and store it for a long time. OAE still needs comprehensive assessment of its safety and effectiveness. We studied an idealised OAE application in a natural low-nutrient ecosystem over 1 month. Our results showed that biogeochemical functioning remained mostly stable but that the long-term capability for storing carbon may be limited at high alkalinity concentration.
Alain Fumenia, Hubert Loisel, Rick A. Reynolds, and Dariusz Stramski
Biogeosciences, 22, 2461–2484, https://doi.org/10.5194/bg-22-2461-2025, https://doi.org/10.5194/bg-22-2461-2025, 2025
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Particulate organic nitrogen (PON) plays a central role in ocean biogeochemistry, yet limited in situ data hinder a full understanding of PON variability and associated processes. Measurements of optical properties offer an alternative for assessing PON across diverse marine environments. Our analysis reveals strong relationships between PON and optical properties, supporting a promising means to assess PON from optical measurements performed in situ or conducted from remote-sensing platforms.
Madhavan Girijakumari Keerthi, Olivier Aumont, Lester Kwiatkowski, and Marina Levy
Biogeosciences, 22, 2163–2180, https://doi.org/10.5194/bg-22-2163-2025, https://doi.org/10.5194/bg-22-2163-2025, 2025
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We assessed how well climate models replicate sub-seasonal changes in ocean chlorophyll observed by satellites. Models struggle to capture these variations accurately. Some overestimate fluctuations and their impact on annual chlorophyll variability, while others underestimate them. The underestimation is likely due to limited model resolution, while the overestimation may come from internal model oscillations.
Gesa Schulz, Kirstin Dähnke, Tina Sanders, Jan Penopp, Hermann W. Bange, Rena Czeschel, and Birgit Gaye
EGUsphere, https://doi.org/10.5194/egusphere-2025-1660, https://doi.org/10.5194/egusphere-2025-1660, 2025
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Oxygen minimum zones (OMZs) are low-oxygen ocean areas that deplete nitrogen, a key marine nutrient. Understanding nitrogen cycling in OMZs is crucial for the global nitrogen cycle. This study examined nitrogen cycling in the OMZ of the Bay of Bengal and East Equatorial Indian Ocean, revealing limited mixing between both regions. Surface phytoplankton consumes nitrate, while deeper nitrification recycles nitrogen. In the BoB’s OMZ (100–300 m), nitrogen loss likely occurs via anammox.
Adam V. Subhas, Jennie E. Rheuban, Zhaohui Aleck Wang, Daniel C. McCorkle, Anna P. M. Michel, Lukas Marx, Chloe L. Dean, Kate Morkeski, Matthew G. Hayden, Mary Burkitt-Gray, Francis Elder, Yiming Guo, Heather H. Kim, and Ke Chen
EGUsphere, https://doi.org/10.5194/egusphere-2025-1348, https://doi.org/10.5194/egusphere-2025-1348, 2025
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Ocean alkalinity enhancement (OAE) is a carbon removal approach in which alkaline materials are added to the marine environment, increasing the ocean's ability to store carbon dioxide. We conducted an open-water experiment releasing and tracking a fluorescent water tracer. Under the right conditions, in-water monitoring of OAE does appear to be possible. We conclude with a series of practical recommendations for open-water OAE monitoring.
Jens Terhaar
Biogeosciences, 22, 1631–1649, https://doi.org/10.5194/bg-22-1631-2025, https://doi.org/10.5194/bg-22-1631-2025, 2025
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The ocean is a major natural carbon sink. Despite its importance, estimates of the ocean carbon sink remain uncertain. Here, I present a hybrid model estimate of the ocean carbon sink from 1959 to 2022. By combining ocean models in hindcast mode and Earth system models, I keep the strength of each approach and remove the respective weaknesses. This composite model estimate is similar in magnitude to the best estimate of the Global Carbon Budget but 70 % less uncertain.
Huailin Deng, Koji Suzuki, Ichiro Yasuda, Hiroshi Ogawa, and Jun Nishioka
Biogeosciences, 22, 1495–1508, https://doi.org/10.5194/bg-22-1495-2025, https://doi.org/10.5194/bg-22-1495-2025, 2025
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Iron (Fe) and nitrate are vital for primary production in the North Pacific. Sedimentary Fe is carried by North Pacific Intermediate Water to the North Pacific, but the nutrient return path and its effect on phytoplankton are unclear. By combining Fe and macronutrient fluxes with phytoplankton composition, this study firstly revealed that Fe supply from the subsurface greatly controls diatom abundance and identified the nutrient return path in the subarctic gyre and Kuroshio–Oyashio transition area.
Alexandre Accardo, Rémi Laxenaire, Alberto Baudena, Sabrina Speich, Rainer Kiko, and Lars Stemmann
Biogeosciences, 22, 1183–1201, https://doi.org/10.5194/bg-22-1183-2025, https://doi.org/10.5194/bg-22-1183-2025, 2025
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The open ocean helps mitigate climate change by storing CO2 via the biological carbon pump (BCP), which involves processes like organic carbon production at the surface and transferring it to the deep ocean via various pathways. By deploying an autonomous platform, we found significant marine snow accumulation from the surface to the mesopelagic zone in frontal regions between eddies. We suggest that the coupling of hydrodynamics at eddy edges and biological activity may enhance this process.
Naoya Kanna, Kazutaka Tateyama, Takuji Waseda, Anna Timofeeva, Maria Papadimitraki, Laura Whitmore, Hajime Obata, Daiki Nomura, Hiroshi Ogawa, Youhei Yamashita, and Igor Polyakov
Biogeosciences, 22, 1057–1076, https://doi.org/10.5194/bg-22-1057-2025, https://doi.org/10.5194/bg-22-1057-2025, 2025
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This article presents data on iron and manganese, essential micronutrients for primary producers in the Arctic Laptev and East Siberian seas (LESS). There, observations were made through international cooperation with the Nansen and Amundsen Basin Observational System expedition during the late summer of 2021. The results from this study indicate that the major sources controlling the iron and manganese distributions on the LESS continental margins are river discharge and shelf sediment input.
Ben J. Fisher, Alex J. Poulton, Michael P. Meredith, Kimberlee Baldry, Oscar Schofield, and Sian F. Henley
Biogeosciences, 22, 975–994, https://doi.org/10.5194/bg-22-975-2025, https://doi.org/10.5194/bg-22-975-2025, 2025
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The Southern Ocean is a rapidly warming environment, with subsequent impacts on ecosystems and biogeochemical cycling. This study examines changes in phytoplankton and biogeochemistry using a range of climate models. Under climate change, the Southern Ocean will be warmer, more acidic and more productive and will have reduced nutrient availability by 2100. However, there is substantial variability between models across key productivity parameters. We propose ways of reducing this uncertainty.
Pearse J. Buchanan, Juan J. Pierella Karlusich, Robyn E. Tuerena, Roxana Shafiee, E. Malcolm S. Woodward, Chris Bowler, and Alessandro Tagliabue
EGUsphere, https://doi.org/10.5194/egusphere-2024-3639, https://doi.org/10.5194/egusphere-2024-3639, 2025
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Ammonium is a form of nitrogen that may become more important for growth of marine primary producers (i.e., phytoplankton) in the future. Because some phytoplankton taxa have a greater affinity for ammonium than others, the relative increase in ammonium could cause shifts in community composition. We quantify ammonium enrichment, identify its drivers, and isolate the possible effect on phytoplankton community composition under a high emissions scenario.
David Curbelo-Hernández, Fiz F. Pérez, Melchor González-Dávila, Sergey V. Gladyshev, Aridane G. González, David González-Santana, Antón Velo, Alexey Sokov, and J. Magdalena Santana-Casiano
Biogeosciences, 21, 5561–5589, https://doi.org/10.5194/bg-21-5561-2024, https://doi.org/10.5194/bg-21-5561-2024, 2024
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The study evaluated CO2–carbonate system dynamics in the North Atlantic subpolar gyre during 2009–2019. Significant ocean acidification, largely due to rising anthropogenic CO2 levels, was found. Cooling, freshening, and enhanced convective processes intensified this trend, affecting calcite and aragonite saturation. The findings contribute to a deeper understanding of ocean acidification and improve our knowledge about its impact on marine ecosystems.
Yuye Han, Zvi Steiner, Zhimian Cao, Di Fan, Junhui Chen, Jimin Yu, and Minhan Dai
EGUsphere, https://doi.org/10.5194/egusphere-2024-3492, https://doi.org/10.5194/egusphere-2024-3492, 2024
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Coccolithophore calcite accounts for a major fraction of particulate inorganic carbon (PIC) standing stocks in the western North Pacific, with a markedly higher contribution in the oligotrophic subtropical gyre than in the Kuroshio-Oyashio transition region, which highlights the importance of coccolithophores for PIC production in the pelagic ocean. We also found extensive dissolution of coccolithophore calcite in the oversaturated shallow waters primarily driven by microbial metabolic activity.
Louise Delaigue, Gert-Jan Reichart, Chris Galley, Yasmina Ourradi, and Matthew Paul Humphreys
EGUsphere, https://doi.org/10.5194/egusphere-2024-2853, https://doi.org/10.5194/egusphere-2024-2853, 2024
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Our study analyzed pH in ocean surface waters to understand how they fluctuate with changes in temperature, salinity, and biological activities. We found that temperature mainly controls daily pH variations, but biological processes also play a role, especially in affecting CO2 levels between the ocean and atmosphere. Our research shows how these factors together maintain the balance of ocean chemistry, which is crucial for predicting changes in marine environments.
Medhavi Pandey, Haimanti Biswas, Daniel Birgel, Nicole Burdanowitz, and Birgit Gaye
Biogeosciences, 21, 4681–4698, https://doi.org/10.5194/bg-21-4681-2024, https://doi.org/10.5194/bg-21-4681-2024, 2024
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We analysed sea surface temperature (SST) proxy and plankton biomarkers in sediments that accumulate sinking material signatures from surface waters in the central Arabian Sea (21°–11° N, 64° E), a tropical basin impacted by monsoons. We saw a north–south SST gradient, and the biological proxies showed more organic matter from larger algae in the north. Smaller algae and zooplankton were more numerous in the south. These trends were related to ocean–atmospheric processes and oxygen availability.
Allison Hogikyan and Laure Resplandy
Biogeosciences, 21, 4621–4636, https://doi.org/10.5194/bg-21-4621-2024, https://doi.org/10.5194/bg-21-4621-2024, 2024
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Rising atmospheric CO2 influences ocean carbon chemistry, leading to ocean acidification. Global warming introduces spatial patterns in the intensity of ocean acidification. We show that the most prominent spatial patterns are controlled by warming-driven changes in rainfall and evaporation, not by the direct effect of warming on carbon chemistry and pH. These evaporation and rainfall patterns oppose acidification in saltier parts of the ocean and enhance acidification in fresher regions.
Shunya Koseki, Lander R. Crespo, Jerry Tjiputra, Filippa Fransner, Noel S. Keenlyside, and David Rivas
Biogeosciences, 21, 4149–4168, https://doi.org/10.5194/bg-21-4149-2024, https://doi.org/10.5194/bg-21-4149-2024, 2024
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We investigated how the physical biases of an Earth system model influence the marine biogeochemical processes in the tropical Atlantic. With four different configurations of the model, we have shown that the versions with better SST reproduction tend to better represent the primary production and air–sea CO2 flux in terms of climatology, seasonal cycle, and response to climate variability.
Lyuba Novi, Annalisa Bracco, Takamitsu Ito, and Yohei Takano
Biogeosciences, 21, 3985–4005, https://doi.org/10.5194/bg-21-3985-2024, https://doi.org/10.5194/bg-21-3985-2024, 2024
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We explored the relationship between oxygen and stratification in the North Pacific Ocean using a combination of data mining and machine learning. We used isopycnic potential vorticity (IPV) as an indicator to quantify ocean ventilation and analyzed its predictability, a strong O2–IPV connection, and predictability for IPV in the tropical Pacific. This opens new routes for monitoring ocean O2 through few observational sites co-located with more abundant IPV measurements in the tropical Pacific.
Winfred Marshal, Jing Xiang Chung, Nur Hidayah Roseli, Roswati Md Amin, and Mohd Fadzil Bin Mohd Akhir
Biogeosciences, 21, 4007–4035, https://doi.org/10.5194/bg-21-4007-2024, https://doi.org/10.5194/bg-21-4007-2024, 2024
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This study stands out for thoroughly examining CMIP6 ESMs' ability to simulate biogeochemical variables in the southern South China Sea, an economically important region. It assesses variables like chlorophyll, phytoplankton, nitrate, and oxygen on annual and seasonal scales. While global assessments exist, this study addresses a gap by objectively ranking 13 CMIP6 ocean biogeochemistry models' performance at a regional level, focusing on replicating specific observed biogeochemical variables.
Jens Terhaar
Biogeosciences, 21, 3903–3926, https://doi.org/10.5194/bg-21-3903-2024, https://doi.org/10.5194/bg-21-3903-2024, 2024
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Despite the ocean’s importance in the carbon cycle and hence the climate, observing the ocean carbon sink remains challenging. Here, I use an ensemble of 12 models to understand drivers of decadal trends of the past, present, and future ocean carbon sink. I show that 80 % of the decadal trends in the multi-model mean ocean carbon sink can be explained by changes in decadal trends in atmospheric CO2. The remaining 20 % are due to internal climate variability and ocean heat uptake.
Reiner Steinfeldt, Monika Rhein, and Dagmar Kieke
Biogeosciences, 21, 3839–3867, https://doi.org/10.5194/bg-21-3839-2024, https://doi.org/10.5194/bg-21-3839-2024, 2024
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We calculate the amount of anthropogenic carbon (Cant) in the Atlantic for the years 1990, 2000, 2010 and 2020. Cant is the carbon that is taken up by the ocean as a result of humanmade CO2 emissions. To determine the amount of Cant, we apply a technique that is based on the observations of other humanmade gases (e.g., chlorofluorocarbons). Regionally, changes in ocean ventilation have an impact on the storage of Cant. Overall, the increase in Cant is driven by the rising CO2 in the atmosphere.
Stephanie Delacroix, Tor Jensen Nystuen, August E. Dessen Tobiesen, Andrew L. King, and Erik Höglund
Biogeosciences, 21, 3677–3690, https://doi.org/10.5194/bg-21-3677-2024, https://doi.org/10.5194/bg-21-3677-2024, 2024
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The addition of alkaline minerals into the ocean might reduce excessive anthropogenic CO2 emissions. Magnesium hydroxide can be added in large amounts because of its low seawater solubility without reaching harmful pH levels. The toxicity effect results of magnesium hydroxide, by simulating the expected concentrations from a ship's dispersion scenario, demonstrated low impacts on both sensitive and local assemblages of marine microalgae when compared to calcium hydroxide.
Precious Mongwe, Matthew Long, Takamitsu Ito, Curtis Deutsch, and Yeray Santana-Falcón
Biogeosciences, 21, 3477–3490, https://doi.org/10.5194/bg-21-3477-2024, https://doi.org/10.5194/bg-21-3477-2024, 2024
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We use a collection of measurements that capture the physiological sensitivity of organisms to temperature and oxygen and a CESM1 large ensemble to investigate how natural climate variations and climate warming will impact the ability of marine heterotrophic marine organisms to support habitats in the future. We find that warming and dissolved oxygen loss over the next several decades will reduce the volume of ocean habitats and will increase organisms' vulnerability to extremes.
Charly A. Moras, Tyler Cyronak, Lennart T. Bach, Renaud Joannes-Boyau, and Kai G. Schulz
Biogeosciences, 21, 3463–3475, https://doi.org/10.5194/bg-21-3463-2024, https://doi.org/10.5194/bg-21-3463-2024, 2024
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We investigate the effects of mineral grain size and seawater salinity on magnesium hydroxide dissolution and calcium carbonate precipitation kinetics for ocean alkalinity enhancement. Salinity did not affect the dissolution, but calcium carbonate formed earlier at lower salinities due to the lower magnesium and dissolved organic carbon concentrations. Smaller grain sizes dissolved faster but calcium carbonate precipitated earlier, suggesting that medium grain sizes are optimal for kinetics.
Rosie M. Sheward, Christina Gebühr, Jörg Bollmann, and Jens O. Herrle
Biogeosciences, 21, 3121–3141, https://doi.org/10.5194/bg-21-3121-2024, https://doi.org/10.5194/bg-21-3121-2024, 2024
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How quickly do marine microorganisms respond to salinity stress? Our experiments with the calcifying marine plankton Emiliania huxleyi show that growth and cell morphology responded to salinity stress within as little as 24–48 hours, demonstrating that morphology and calcification are sensitive to salinity over a range of timescales. Our results have implications for understanding the short-term role of E. huxleyi in biogeochemical cycles and in size-based paleoproxies for salinity.
Laura Marín-Samper, Javier Arístegui, Nauzet Hernández-Hernández, Joaquín Ortiz, Stephen D. Archer, Andrea Ludwig, and Ulf Riebesell
Biogeosciences, 21, 2859–2876, https://doi.org/10.5194/bg-21-2859-2024, https://doi.org/10.5194/bg-21-2859-2024, 2024
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Our planet is facing a climate crisis. Scientists are working on innovative solutions that will aid in capturing the hard to abate emissions before it is too late. Exciting research reveals that ocean alkalinity enhancement, a key climate change mitigation strategy, does not harm phytoplankton, the cornerstone of marine ecosystems. Through meticulous study, we may have uncovered a positive relationship: up to a specific limit, enhancing ocean alkalinity boosts photosynthesis by certain species.
Kieran Curran, Tracy Villareal, and Robert T. Letscher
EGUsphere, https://doi.org/10.5194/egusphere-2024-1416, https://doi.org/10.5194/egusphere-2024-1416, 2024
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This work provides a two year record of marine organic gel concentrations from an open ocean site in the subtropical North Pacific Ocean north of Hawaii. These microscopic gels are investigated to understand their importance as an understudied component of organic matter cycling by marine microbes. We find an important role for gel cycling during the summer months, helping explain previously contradictory estimates of nutrient supply and demand for the subtropical ocean.
France Van Wambeke, Pascal Conan, Mireille Pujo-Pay, Vincent Taillandier, Olivier Crispi, Alexandra Pavlidou, Sandra Nunige, Morgane Didry, Christophe Salmeron, and Elvira Pulido-Villena
Biogeosciences, 21, 2621–2640, https://doi.org/10.5194/bg-21-2621-2024, https://doi.org/10.5194/bg-21-2621-2024, 2024
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Phosphomonoesterase (PME) and phosphodiesterase (PDE) activities over the epipelagic zone are described in the eastern Mediterranean Sea in winter and autumn. The types of concentration kinetics obtained for PDE (saturation at 50 µM, high Km, high turnover times) compared to those of PME (saturation at 1 µM, low Km, low turnover times) are discussed in regard to the possible inequal distribution of PDE and PME in the size continuum of organic material and accessibility to phosphodiesters.
Jenny Hieronymus, Magnus Hieronymus, Matthias Gröger, Jörg Schwinger, Raffaele Bernadello, Etienne Tourigny, Valentina Sicardi, Itzel Ruvalcaba Baroni, and Klaus Wyser
Biogeosciences, 21, 2189–2206, https://doi.org/10.5194/bg-21-2189-2024, https://doi.org/10.5194/bg-21-2189-2024, 2024
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The timing of the net primary production annual maxima in the North Atlantic in the period 1750–2100 is investigated using two Earth system models and the high-emissions scenario SSP5-8.5. It is found that, for most of the region, the annual maxima occur progressively earlier, with the most change occurring after the year 2000. Shifts in the seasonality of the primary production may impact the entire ecosystem, which highlights the need for long-term monitoring campaigns in this area.
Nicole M. Travis, Colette L. Kelly, and Karen L. Casciotti
Biogeosciences, 21, 1985–2004, https://doi.org/10.5194/bg-21-1985-2024, https://doi.org/10.5194/bg-21-1985-2024, 2024
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We conducted experimental manipulations of light level on microbial communities from the primary nitrite maximum. Overall, while individual microbial processes have different directions and magnitudes in their response to increasing light, the net community response is a decline in nitrite production with increasing light. We conclude that while increased light may decrease net nitrite production, high-light conditions alone do not exclude nitrification from occurring in the surface ocean.
Zoë Rebecca van Kemenade, Zeynep Erdem, Ellen Christine Hopmans, Jaap Smede Sinninghe Damsté, and Darci Rush
Biogeosciences, 21, 1517–1532, https://doi.org/10.5194/bg-21-1517-2024, https://doi.org/10.5194/bg-21-1517-2024, 2024
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The California Current system (CCS) hosts the eastern subtropical North Pacific oxygen minimum zone (ESTNP OMZ). This study shows anaerobic ammonium oxidizing (anammox) bacteria cause a loss of bioavailable nitrogen (N) in the ESTNP OMZ throughout the late Quaternary. Anammox occurred during both glacial and interglacial periods and was driven by the supply of organic matter and changes in ocean currents. These findings may have important consequences for biogeochemical models of the CCS.
Cathy Wimart-Rousseau, Tobias Steinhoff, Birgit Klein, Henry Bittig, and Arne Körtzinger
Biogeosciences, 21, 1191–1211, https://doi.org/10.5194/bg-21-1191-2024, https://doi.org/10.5194/bg-21-1191-2024, 2024
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The marine CO2 system can be measured independently and continuously by BGC-Argo floats since numerous pH sensors have been developed to suit these autonomous measurements platforms. By applying the Argo correction routines to float pH data acquired in the subpolar North Atlantic Ocean, we report the uncertainty and lack of objective criteria associated with the choice of the reference method as well the reference depth for the pH correction.
Sabine Mecking and Kyla Drushka
Biogeosciences, 21, 1117–1133, https://doi.org/10.5194/bg-21-1117-2024, https://doi.org/10.5194/bg-21-1117-2024, 2024
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This study investigates whether northeastern North Pacific oxygen changes may be caused by surface density changes in the northwest as water moves along density horizons from the surface into the subsurface ocean. A correlation is found with a lag that about matches the travel time of water from the northwest to the northeast. Salinity is the main driver causing decadal changes in surface density, whereas salinity and temperature contribute about equally to long-term declining density trends.
Takamitsu Ito, Hernan E. Garcia, Zhankun Wang, Shoshiro Minobe, Matthew C. Long, Just Cebrian, James Reagan, Tim Boyer, Christopher Paver, Courtney Bouchard, Yohei Takano, Seth Bushinsky, Ahron Cervania, and Curtis A. Deutsch
Biogeosciences, 21, 747–759, https://doi.org/10.5194/bg-21-747-2024, https://doi.org/10.5194/bg-21-747-2024, 2024
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This study aims to estimate how much oceanic oxygen has been lost and its uncertainties. One major source of uncertainty comes from the statistical gap-filling methods. Outputs from Earth system models are used to generate synthetic observations where oxygen data are extracted from the model output at the location and time of historical oceanographic cruises. Reconstructed oxygen trend is approximately two-thirds of the true trend.
Robert W. Izett, Katja Fennel, Adam C. Stoer, and David P. Nicholson
Biogeosciences, 21, 13–47, https://doi.org/10.5194/bg-21-13-2024, https://doi.org/10.5194/bg-21-13-2024, 2024
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This paper provides an overview of the capacity to expand the global coverage of marine primary production estimates using autonomous ocean-going instruments, called Biogeochemical-Argo floats. We review existing approaches to quantifying primary production using floats, provide examples of the current implementation of the methods, and offer insights into how they can be better exploited. This paper is timely, given the ongoing expansion of the Biogeochemical-Argo array.
Qian Liu, Yingjie Liu, and Xiaofeng Li
Biogeosciences, 20, 4857–4874, https://doi.org/10.5194/bg-20-4857-2023, https://doi.org/10.5194/bg-20-4857-2023, 2023
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In the Southern Ocean, abundant eddies behave opposite to our expectations. That is, anticyclonic (cyclonic) eddies are cold (warm). By investigating the variations of physical and biochemical parameters in eddies, we find that abnormal eddies have unique and significant effects on modulating the parameters. This study fills a gap in understanding the effects of abnormal eddies on physical and biochemical parameters in the Southern Ocean.
Caroline Ulses, Claude Estournel, Patrick Marsaleix, Karline Soetaert, Marine Fourrier, Laurent Coppola, Dominique Lefèvre, Franck Touratier, Catherine Goyet, Véronique Guglielmi, Fayçal Kessouri, Pierre Testor, and Xavier Durrieu de Madron
Biogeosciences, 20, 4683–4710, https://doi.org/10.5194/bg-20-4683-2023, https://doi.org/10.5194/bg-20-4683-2023, 2023
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Deep convection plays a key role in the circulation, thermodynamics, and biogeochemical cycles in the Mediterranean Sea, considered to be a hotspot of biodiversity and climate change. In this study, we investigate the seasonal and annual budget of dissolved inorganic carbon in the deep-convection area of the northwestern Mediterranean Sea.
Daniela König and Alessandro Tagliabue
Biogeosciences, 20, 4197–4212, https://doi.org/10.5194/bg-20-4197-2023, https://doi.org/10.5194/bg-20-4197-2023, 2023
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Using model simulations, we show that natural and anthropogenic changes in the global climate leave a distinct fingerprint in the isotopic signatures of iron in the surface ocean. We find that these climate effects on iron isotopes are often caused by the redistribution of iron from different external sources to the ocean, due to changes in ocean currents, and by changes in algal growth, which take up iron. Thus, isotopes may help detect climate-induced changes in iron supply and algal uptake.
Chloé Baumas, Robin Fuchs, Marc Garel, Jean-Christophe Poggiale, Laurent Memery, Frédéric A. C. Le Moigne, and Christian Tamburini
Biogeosciences, 20, 4165–4182, https://doi.org/10.5194/bg-20-4165-2023, https://doi.org/10.5194/bg-20-4165-2023, 2023
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Through the sink of particles in the ocean, carbon (C) is exported and sequestered when reaching 1000 m. Attempts to quantify C exported vs. C consumed by heterotrophs have increased. Yet most of the conducted estimations have led to C demands several times higher than C export. The choice of parameters greatly impacts the results. As theses parameters are overlooked, non-accurate values are often used. In this study we show that C budgets can be well balanced when using appropriate values.
Anna Belcher, Sian F. Henley, Katharine Hendry, Marianne Wootton, Lisa Friberg, Ursula Dallman, Tong Wang, Christopher Coath, and Clara Manno
Biogeosciences, 20, 3573–3591, https://doi.org/10.5194/bg-20-3573-2023, https://doi.org/10.5194/bg-20-3573-2023, 2023
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The oceans play a crucial role in the uptake of atmospheric carbon dioxide, particularly the Southern Ocean. The biological pumping of carbon from the surface to the deep ocean is key to this. Using sediment trap samples from the Scotia Sea, we examine biogeochemical fluxes of carbon, nitrogen, and biogenic silica and their stable isotope compositions. We find phytoplankton community structure and physically mediated processes are important controls on particulate fluxes to the deep ocean.
Asmita Singh, Susanne Fietz, Sandy J. Thomalla, Nicolas Sanchez, Murat V. Ardelan, Sébastien Moreau, Hanna M. Kauko, Agneta Fransson, Melissa Chierici, Saumik Samanta, Thato N. Mtshali, Alakendra N. Roychoudhury, and Thomas J. Ryan-Keogh
Biogeosciences, 20, 3073–3091, https://doi.org/10.5194/bg-20-3073-2023, https://doi.org/10.5194/bg-20-3073-2023, 2023
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Despite the scarcity of iron in the Southern Ocean, seasonal blooms occur due to changes in nutrient and light availability. Surprisingly, during an autumn bloom in the Antarctic sea-ice zone, the results from incubation experiments showed no significant photophysiological response of phytoplankton to iron addition. This suggests that ambient iron concentrations were sufficient, challenging the notion of iron deficiency in the Southern Ocean through extended iron-replete post-bloom conditions.
Benoît Pasquier, Mark Holzer, Matthew A. Chamberlain, Richard J. Matear, Nathaniel L. Bindoff, and François W. Primeau
Biogeosciences, 20, 2985–3009, https://doi.org/10.5194/bg-20-2985-2023, https://doi.org/10.5194/bg-20-2985-2023, 2023
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Modeling the ocean's carbon and oxygen cycles accurately is challenging. Parameter optimization improves the fit to observed tracers but can introduce artifacts in the biological pump. Organic-matter production and subsurface remineralization rates adjust to compensate for circulation biases, changing the pathways and timescales with which nutrients return to the surface. Circulation biases can thus strongly alter the system’s response to ecological change, even when parameters are optimized.
Priyanka Banerjee
Biogeosciences, 20, 2613–2643, https://doi.org/10.5194/bg-20-2613-2023, https://doi.org/10.5194/bg-20-2613-2023, 2023
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This study shows that atmospheric deposition is the most important source of iron to the upper northern Indian Ocean for phytoplankton growth. This is followed by iron from continental-shelf sediment. Phytoplankton increase following iron addition is possible only with high background levels of nitrate. Vertical mixing is the most important physical process supplying iron to the upper ocean in this region throughout the year. The importance of ocean currents in supplying iron varies seasonally.
Iris Kriest, Julia Getzlaff, Angela Landolfi, Volkmar Sauerland, Markus Schartau, and Andreas Oschlies
Biogeosciences, 20, 2645–2669, https://doi.org/10.5194/bg-20-2645-2023, https://doi.org/10.5194/bg-20-2645-2023, 2023
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Global biogeochemical ocean models are often subjectively assessed and tuned against observations. We applied different strategies to calibrate a global model against observations. Although the calibrated models show similar tracer distributions at the surface, they differ in global biogeochemical fluxes, especially in global particle flux. Simulated global volume of oxygen minimum zones varies strongly with calibration strategy and over time, rendering its temporal extrapolation difficult.
John C. Tracey, Andrew R. Babbin, Elizabeth Wallace, Xin Sun, Katherine L. DuRussel, Claudia Frey, Donald E. Martocello III, Tyler Tamasi, Sergey Oleynik, and Bess B. Ward
Biogeosciences, 20, 2499–2523, https://doi.org/10.5194/bg-20-2499-2023, https://doi.org/10.5194/bg-20-2499-2023, 2023
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Nitrogen (N) is essential for life; thus, its availability plays a key role in determining marine productivity. Using incubations of seawater spiked with a rare form of N measurable on a mass spectrometer, we quantified microbial pathways that determine marine N availability. The results show that pathways that recycle N have higher rates than those that result in its loss from biomass and present new evidence for anaerobic nitrite oxidation, a process long thought to be strictly aerobic.
Amanda Gerotto, Hongrui Zhang, Renata Hanae Nagai, Heather M. Stoll, Rubens César Lopes Figueira, Chuanlian Liu, and Iván Hernández-Almeida
Biogeosciences, 20, 1725–1739, https://doi.org/10.5194/bg-20-1725-2023, https://doi.org/10.5194/bg-20-1725-2023, 2023
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Based on the analysis of the response of coccolithophores’ morphological attributes in a laboratory dissolution experiment and surface sediment samples from the South China Sea, we proposed that the thickness shape (ks) factor of fossil coccoliths together with the normalized ks variation, which is the ratio of the standard deviation of ks (σ) over the mean ks (σ/ks), is a robust and novel proxy to reconstruct past changes in deep ocean carbon chemistry.
Katherine E. Turner, Doug M. Smith, Anna Katavouta, and Richard G. Williams
Biogeosciences, 20, 1671–1690, https://doi.org/10.5194/bg-20-1671-2023, https://doi.org/10.5194/bg-20-1671-2023, 2023
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We present a new method for reconstructing ocean carbon using climate models and temperature and salinity observations. To test this method, we reconstruct modelled carbon using synthetic observations consistent with current sampling programmes. Sensitivity tests show skill in reconstructing carbon trends and variability within the upper 2000 m. Our results indicate that this method can be used for a new global estimate for ocean carbon content.
Alexandre Mignot, Hervé Claustre, Gianpiero Cossarini, Fabrizio D'Ortenzio, Elodie Gutknecht, Julien Lamouroux, Paolo Lazzari, Coralie Perruche, Stefano Salon, Raphaëlle Sauzède, Vincent Taillandier, and Anna Teruzzi
Biogeosciences, 20, 1405–1422, https://doi.org/10.5194/bg-20-1405-2023, https://doi.org/10.5194/bg-20-1405-2023, 2023
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Numerical models of ocean biogeochemistry are becoming a major tool to detect and predict the impact of climate change on marine resources and monitor ocean health. Here, we demonstrate the use of the global array of BGC-Argo floats for the assessment of biogeochemical models. We first detail the handling of the BGC-Argo data set for model assessment purposes. We then present 23 assessment metrics to quantify the consistency of BGC model simulations with respect to BGC-Argo data.
Cited articles
Accornero, A., Manno, C., Esposito, F., and Gambi, M. C.: The vertical flux of particulate matter in the polynya of Terra Nova Bay. Part II. Biological components, Antarct. Sci., 15, 175–188, https://doi.org/10.1017/S0954102003001214, 2003.
Andersson, A. J., Mackenzie, F. T., and Gattuso, J.-P.: Effects of ocean acidification on benthic processes, organisms, and ecosystems, in: Ocean Acidification, edited by: Gattuso, J.-P. and Hanson, L., Oxford University Press, New York, USA, 122–153, 2011.
Archer, D., Eby, M., Brovkin, V., Ridgwell, A., Cao, L., Mikolajewicz, U., Caldeira, K., Matsumoto, K., Munhoven, G., Montenegro, A., and Tokos, K.: Atmospheric Lifetime of Fossil Fuel Carbon Dioxide, Annu. Rev. Earth Pl. Sc., 37, 117–134, https://doi.org/10.1146/annurev.earth.031208.100206, 2009.
Arrigo, K. R. and McClain, C. R.: Spring Phytoplankton Production in the Western Ross Sea, Science, 266, 261–263, https://doi.org/10.1126/science.266.5183.261, 1994.
Arrigo, K. R. and van Dijken, G. L.: Phytoplankton dynamics within 37 Antarctic coastal polynya systems, J. Geophys. Res., 108, 3271, https://doi.org/10.1029/2002JC001739, 2003.
Arrigo, K. R. and van Dijken, G. L.: Annual changes in sea-ice, chlorophyll a, and primary production in the Ross Sea, Antarctica, Deep-Sea Res. Pt. II, 51, 117–138, https://doi.org/10.1016/j.dsr2.2003.04.003, 2004.
Arrigo, K. R. and van Dijken, G. L.: Interannual variation in air-sea CO2 flux in the Ross Sea, Antarctica: A model analysis, J. Geophys. Res., 112, 1–16, https://doi.org/10.1029/2006JC003492, 2007.
Arrigo, K. R., Robinson, D. H., Worthen, D. L., Dunbar, R. B., DiTullio, G. R., VanWoert, M., and Lizotte, M. P.: Phytoplankton community structure and the drawdown of nutrients and CO2 in the Southern Ocean, Science, 283, 365–367, https://doi.org/10.1126/science.283.5400.365, 1999.
Arrigo, K. R., Worthen, D. L., and Robinson, D. H.: A coupled ocean-ecosystem model of the Ross Sea: 2. Iron regulation of phytoplankton taxonomic variability and primary production, J. Geophys. Res., 108, 3231, https://doi.org/10.1029/2001JC000856, 2003.
Arrigo, K. R., van Dijken, G. L., and Bushinsky, S.: Primary production in the Southern Ocean, 1997–2006, J. Geophys. Res., 113, C08004, https://doi.org/10.1029/2007JC004551, 2008.
Bates, N. R., Hansell, D. A., Carlson, C. A., and Gordon, L. I.: Distribution of CO2 species, estimates of net community production, and air-sea CO2 exchange in the Ross Sea polynya, J. Geophys. Res., 103, 2883–2896, https://doi.org/10.1029/97jc02473, 1998.
Bates, N. R., Orchowska, M. I., Garley, R., and Mathis, J. T.: Summertime calcium carbonate undersaturation in shelf waters of the western Arctic Ocean – how biological processes exacerbate the impact of ocean acidification, Biogeosciences, 10, 5281–5309, https://doi.org/10.5194/bg-10-5281-2013, 2013.
Bednaršek, N., Tarling, G. A., Bakker, D. C. E., Fielding, S., Jones, E. M., Venables, H. J., Ward, P., Kuzirian, A., Lézé, B., Feely, R. A., and Murphy, E. J.: Extensive dissolution of live pteropods in the Southern Ocean, Nat. Geosci., 5, 881–885, https://doi.org/10.1038/ngeo1635, 2012.
Bednaršek, N., Tarling, G. A., Bakker, D. C., Fielding, S., and Feely, R. A.: Dissolution dominating calcification process in polar pteropods close to the point of aragonite undersaturation, PLoS One, 9, e109183, https://doi.org/10.1371/journal.pone.0109183, 2014.
Bresnahan, P. J., Martz, T. R., Takeshita, Y., Johnson, K. S., and Lashomb, M.: Best practices for autonomous measurement of seawater pH with the Honeywell Durafet, Methods Oceanogr., 9, 1–33, https://doi.org/10.1016/j.mio.2014.08.003, 2014.
Brewer, P. G. and Goldman, J. C.: Alkalinity changes generated by phytoplankton growth, Limnol. Oceanogr., 21, 108–117, https://doi.org/10.4319/lo.1976.21.1.0108, 1976.
Byrne, M., Ho, M. A., Koleits, L., Price, C., King, C. K., Virtue, P., Tilbrook, B., and Lamare, M.: Vulnerability of the calcifying larval stage of the Antarctic sea urchin Sterechinus neumayeri to near-future ocean acidification and warming, Glob. Change Biol., 19, 2264–2275, https://doi.org/10.1111/gcb.12190, 2013.
Caldeira, K. and Wickett, M. E.: Oceanography: anthropogenic carbon and ocean pH, Nature, 425, p. 365, https://doi.org/10.1038/425365a, 2003.
Chierici, M. and Fransson, A.: Calcium carbonate saturation in the surface water of the Arctic Ocean: undersaturation in freshwater influenced shelves, Biogeosciences, 6, 2421–2431, https://doi.org/10.5194/bg-6-2421-2009, 2009.
Collier, R., Dymond, J., Honjo, S., Manganini, S., Francois, R., and Dunbar, R.: The vertical flux of biogenic and lithogenic material in the Ross Sea: Moored sediment trap observations 1996–1998, Deep-Sea Res. Pt. II, 47, 3491–3520, https://doi.org/10.1016/S0967-0645(00)00076-X, 2000.
Comeau, S., Gorsky, G., Alliouane, S., and Gattuso, J.-P.: Larvae of the pteropod Cavolinia inflexa exposed to aragonite undersaturation are viable but shell-less, Mar. Biol., 157, 2341–2345, https://doi.org/10.1007/s00227-010-1493-6, 2010.
Cummings, V., Hewitt, J., Van Rooyen, A., Currie, K., Beard, S., Thrush, S., Norkko, J., Barr, N., Heath, P., Halliday, N. J., Sedcole, R., Gomez, A., McGraw, C., and Metcalf, V.: Ocean acidification at high latitudes: potential effects on functioning of the Antarctic bivalve Laternula elliptica, PLoS ONE, 6, e16069, https://doi.org/10.1371/journal.pone.0016069, 2011.
Dickson, A. G.: The carbon dioxide system in seawater: equilibrium chemistry and measurements, in: Guide to Best Practices in Ocean Acidification Reseach and Data Reporting, edited by: Riebesell, U., Fabry, V. J., Hansson, L., and Gattuso, J.-P., Office for Official Publications of the European Communities, Luxembourg, 17–40, 2010.
Dickson, A. G. and Millero, F. J.: A comparison of the equilibrium constants for the dissociation of carbonic acid in seawater media, Deep-Sea Res., 34, 1733–1743, https://doi.org/10.1016/0198-0149(87)90021-5, 1987.
Dickson, A. G., Afghan, J. D., and Anderson, G. C.: Reference materials for oceanic CO2 analysis: a method for the certification of total alkalinity, Mar. Chem., 80, 185–197, https://doi.org/10.1016/S0304-4203(02)00133-0, 2003.
Dickson, A. G., Sabine, C. L., and Christian, J. R.: Guide to best practices for ocean CO2 measurements, PICES Spec. Publ., 3, p. 191, https://doi.org/10.1159/000331784, 2007.
Dieckmann, G. S., Nehrke, G., Papadimitriou, S., Göttlicher, J., Steininger, R., Kennedy, H., Wolf-Gladrow, D., and Thomas, D. N.: Calcium carbonate as ikaite crystals in Antarctic sea ice, Geophys. Res. Lett., 35, 35–37, https://doi.org/10.1029/2008GL033540, 2008.
Dinniman, M. S., Klinck, J. M., and Smith, W. O.: A model study of Circumpolar Deep Water on the West Antarctic Peninsula and Ross Sea continental shelves, Deep-Sea Res. Pt. II, 58, 1508–1523, https://doi.org/10.1016/j.dsr2.2010.11.013, 2011.
Ericson, J. A., Ho, M. A., Miskelly, A., King, C. K., Virtue, P., Tilbrook, B., and Byrne, M.: Combined effects of two ocean change stressors, warming and acidification, on fertilization and early development of the Antarctic echinoid Sterechinus neumayeri, Polar Biol., 35, 1027–1034, https://doi.org/10.1007/s00300-011-1150-7, 2012.
Feely, R., Doney, S., and Cooley, S.: Ocean Acidification: Present Conditions and Future Changes in a High-CO2 World, Oceanography, 22, 36–47, https://doi.org/10.5670/oceanog.2009.95, 2009.
Feng, Y., Hare, C. E., Rose, J. M., Handy, S. M., DiTullio, G. R., Lee, P. A., Smith, W. O., Peloquin, J., Tozzi, S., Sun, J., Zhang, Y., Dunbar, R. B., Long, M. C., Sohst, B., Lohan, M., and Hutchins, D. A.: Interactive effects of iron, irradiance and CO2 on Ross Sea phytoplankton, Deep-Sea Res. Pt. I, 57, 368–383, https://doi.org/10.1016/j.dsr.2009.10.013, 2010.
Foster, B. A. and Montgomery, J. C.: Planktivory in benthic nototheniid fish in McMurdo Sound, Antarctica, Environ. Biol. Fish., 36, 313–318, https://doi.org/10.1007/BF00001727, 1993.
Fransson, A., Chierici, M., Yager, P. L., and Smith, W. O.: Antarctic sea ice carbon dioxide system and controls, J. Geophys. Res., 116, C12035, https://doi.org/10.1029/2010JC006844, 2011.
Gannefors, C., Boer, M., Kattner, G., Graeve, M., Eiane, K., Gulliksen, B., Hop, H., and Falk-Petersen, S.: The Arctic sea butterfly Limacina helicina: lipids and life strategy, Mar. Biol., 147, 169–177, https://doi.org/10.1007/s00227-004-1544-y, 2005.
Gibson, J. A. E. and Trull, T. W.: Annual cycle of fCO2 under sea-ice and in open water in Prydz Bay, East Antarctica, Mar. Chem., 66, 187–200, https://doi.org/10.1016/S0304-4203(99)00040-7, 1999.
Gonzalez-Bernat, M. J., Lamare, M., and Barker, M.: Effects of reduced seawater pH on fertilisation, embryogenesis and larval development in the Antarctic seastar Odontaster validus, Polar Biol., 36, 235–247, https://doi.org/10.1007/s00300-012-1255-7, 2013.
Gordon, L. I., Codispoti, L. A., Jennings J. C., J., Millero, F. J., Morrison, J. M., and Sweeney, C.: Seasonal evolution of hydrographic properties in the Ross Sea, Antarctica, 1996–1997, Deep-Sea Res. Pt. II, 47, 3095–3117, https://doi.org/10.1016/S0967-0645(00)00060-6, 2000.
Hauck, J., Hoppema, M., Bellerby, R. G. J., Völker, C., and Wolf-Gladrow, D.: Data-based estimation of anthropogenic carbon and acidification in the Weddell Sea on a decadal timescale, J. Geophys. Res.-Oceans, 115, 1–14, https://doi.org/10.1029/2009JC005479, 2010.
Hauck, J., Arrigo, K. R., Hoppema, M., Van Dijken, G. L., Völker, C. and Wolf-Gladrow, D. A.: Insignificant buffering capacity of Antarctic shelf carbonates, Global Biogeochem. Cy., 27, 11–20, https://doi.org/10.1029/2011GB004211, 2013.
Hauri, C., Gruber, N., Vogt, M., Doney, S. C., Feely, R. A., Lachkar, Z., Leinweber, A., McDonnell, A. M. P., Munnich, M., and Plattner, G.-K.: Spatiotemporal variability and long-term trends of ocean acidification in the California Current System, Biogeosciences, 10, 193–216, https://doi.org/10.5194/bg-10-193-2013, 2013.
Hauri, C., Doney, S. C., Takahashi, T., Erickson, M., Jiang, G., and Ducklow, H. W.: Two decades of inorganic carbon dynamics along the Western Antarctic Peninsula, Biogeosciences Discuss., 12, 6929–6969, https://doi.org/10.5194/bgd-12-6929-2015, 2015.
Hopkins, T. L.: Midwater food web in McMurdo Sound, Ross Sea, Antarctica, Mar. Biol., 96, 93–106, https://doi.org/10.1007/BF00394842, 1987.
Hunt, B. P. V, Pakhomov, E. A., Hosie, G. W., Siegel, V., Ward, P., and Bernard, K.: Pteropods in Southern Ocean ecosystems, Prog. Oceanogr., 78, 193–221, https://doi.org/10.1016/j.pocean.2008.06.001, 2008.
IPCC AR5 WG1, Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change Rep., Cambridge, UK and New York, NY, USA, 1535 pp., 2013.
Jacobs, S. S.: On the nature and significance of the Antarctic Slope Front, Mar. Chem., 35, 9–24, https://doi.org/10.1016/S0304-4203(09)90005-6, 1991.
Jacobs, S. S. and Giulivi, C. F.: Large multidecadal salinity trends near the Pacific-Antarctic continental margin, J. Climate, 23, 4508–4524, https://doi.org/10.1175/2010JCLI3284.1, 2010.
Jacobs, S. S., Fairbanks, R. G., and Horibe, Y.: Origin and evolution of water masses near the Antarctic continental margin: evidence from H218O/H216O ratios in seawater, in: Oceanography of the Antarctic Continental Shelf, Antarctic Research Series, 43, edited by: Jacobs, S. S., American Geophysical Union, Washington, DC, USA, 59–85, 1985.
Kapsenberg, L., Kelley, A. L., Shaw, E. C., Martz, T. R., and Hofmann, G. E.: Near-shore Antarctic pH variability has implications for the design of ocean acidification experiments, Sci. Rep., 5, 9638, https://doi.org/10.1038/srep09638, 2015.
Kawaguchi, S., Ishida, A., King, R., Raymond, B., Waller, N., Constable, A., Nicol, S., Wakita, M., and Ishimatsu, A.: Risk maps for Antarctic krill under projected Southern Ocean acidification, Nat. Clim. Chang., 3, 843–847, https://doi.org/10.1038/nclimate1937, 2013.
Knap, A., Michaels A., Close A., Ducklow, H., and A. Dickson: Protocols for the Joint Global Ocean Flux Study (JGOFS) Core Measurements, JGOFS Rep., 19, 1–170, 1996.
Kohut, J., Hunter, E., and Huber, B.: Small-scale variability of the cross-shelf flow over the outer shelf of the Ross Sea, J. Geophys. Res.-Oceans, 118, 1863–1876, https://doi.org/10.1002/jgrc.20090, 2013.
La Mesa, M., Vacchi, M., and Zunini Sertorio, T.: Feeding plasticity of Trematomus newnesi (Pisces, Nototheniidae) in Terra Nova Bay, Ross Sea, in relation to environmental conditions, Polar Biol., 23, 38–45, https://doi.org/10.1007/s003000050006, 2000.
La Mesa, M., Eastman, J. T., and Vacchi, M.: The role of notothenioid fish in the food web of the Ross Sea shelf waters: A review, Polar Biol., 27, 321–338, https://doi.org/10.1007/s00300-004-0599-z, 2004.
Lee, K., Millero, F. J., Byrne, R. H., Feely, R. A., and Wanninkhof, R.: The recommended dissociation constants for carbonic acid in seawater, Geophys. Res. Lett., 27, 229–232, https://doi.org/10.1029/1999GL002345, 2000.
Lenton, A., Codron, F., Bopp, L., Metzl, N., Cadule, P., Tagliabue, A., and Le Sommer, J.: Stratospheric ozone depletion reduces ocean carbon uptake and enhances ocean acidification, Geophys. Res. Lett., 36, L12606, https://doi.org/10.1029/2009GL038227, 2009.
Lewis, E. and Wallace, D. W. R.: Program Developed for CO2 System Calculations ORNL/CDIAC-105, Carbon Dioxide Information Analysis Centre, Oakridge National Laboratory, US Department of Energy, Oakridge, TN, USA, 1998.
Long, M. C., Dunbar, R. B., Tortell, P. D., Smith, W. O., Mucciarone, D. A., and Ditullio, G. R.: Vertical structure, seasonal drawdown, and net community production in the Ross Sea, Antarctica, J. Geophys. Res.-Oceans, 116, 1–19, https://doi.org/10.1029/2009JC005954, 2011.
Manno, C., Tirelli, V., Accornero, A., and Fonda Umani, S.: Importance of the contribution of limacina helicina faecal pellets to the carbon pump in terra nova bay (Antarctica), J. Plankton Res., 32, 145–152, https://doi.org/10.1093/plankt/fbp108, 2010.
Matson, P. G., Washburn, L., Martz, T. R., and Hofmann, G. E.: Abiotic versus Biotic Drivers of Ocean pH Variation under Fast Sea Ice in McMurdo Sound, Antarctica, 9, e107239, https://doi.org/10.1371/journal.pone.0107239, 2014.
Mattsdotter Björk, M., Fransson, A., Torstensson, A., and Chierici, M.: Ocean acidification state in western Antarctic surface waters: controls and interannual variability, Biogeosciences, 11, 57–73, https://doi.org/10.5194/bg-11-57-2014, 2014.
McClintock, J. B., Angus, R. A., Mcdonald, M. R., Amsler, C. D., Catledge, S. A., and Vohra, Y. K.: Rapid dissolution of shells of weakly calcified antarctic benthic macroorganisms indicates high vulnerability to ocean acidification, Antarct. Sci., 21, 449–456, https://doi.org/10.1017/S0954102009990198, 2009.
McClintock, J. B., Amsler, M. O., Angus, R. A., Challener, R. C., Schram, J. B., Amsler, C. D., Mah, C. L., Cuce, J., and Baker, B. J.: The Mg-Calcite Composition of Antarctic Echinoderms: Important Implications for Predicting the Impacts of Ocean Acidification, J. Geol., 119, 457–466, https://doi.org/10.1086/660890, 2011.
McNeil, B. I. and Matear, R. J.: Southern Ocean acidification: a tipping point at 450-ppm atmospheric CO2, P. Natl. Acad. Sci. USA, 105, 18860–18864, https://doi.org/10.1073/pnas.0806318105, 2008.
McNeil, B. I., Metzl, N., Key, R. M., Matear, R. J., and Corbiere, A.: An empirical estimate of the Southern Ocean air-sea CO2 flux, Global Biogeochem. Cy., 21, GB3011, https://doi.org/10.1029/2007GB002991, 2007.
McNeil, B. I., Tagliabue, A., and Sweeney, C.: A multi-decadal delay in the onset of corrosive acidified waters in the Ross Sea of Antarctica due to strong air-sea CO2 disequilibrium, Geophys. Res. Lett., 37, 1–5, https://doi.org/10.1029/2010GL044597, 2010.
McNeil, B. I., Sweeney, C., and Gibson, J. A. E.: Short Note: Natural seasonal variability of aragonite saturation state within two Antarctic coastal ocean sites, Antarct. Sci., 23, 411–412, https://doi.org/10.1017/S0954102011000204, 2011.
Mehrback, C., Culberson, C. H., Hawley, J. E., and Pytkowicz, R. M.: Measurement of the apparent dissociation constants of carbonic acid in seawater at atmospheric pressure, Limnol. Oceanogr., 18, 897–907, https://doi.org/10.4319/lo.1973.18.6.0897, 1973.
Meinshausen, M., Smith, S. J., Calvin, K., Daniel, J. S., Kainuma, M. L. T., Lamarque, J., Matsumoto, K., Montzka, S. A., Raper, S. C. B., Riahi, K., Thomson, A., Velders, G. J. M. and van Vuuren, D. P. P.: The RCP greenhouse gas concentrations and their extensions from 1765 to 2300, Clim. Change, 109, 213–241, https://doi.org/10.1007/s10584-011-0156-z, 2011.
Metzl, N., Brunet, C., Jabaud-Jan, A., Poisson, A., and Schauer, B.: Summer and winter air-sea CO2 fluxes in the Southern Ocean, Deep-Sea Res. Pt. I, 53, 1548–1563, https://doi.org/10.1016/j.dsr.2006.07.006, 2006.
Millero, F. J., Lee, K., and Roche, M.: Distribution of alkalinity in the surface waters of the major oceans, Mar. Chem., 60, 111–130, 1998.
Millero, F. J., Pierrot, D., Lee, K., Wanninkhof, R., Feely, R., Sabine, C. L., Key, R. M. and Takahashi, T.: Dissociation constants for carbonic acid determined from field measurements, Deep-Sea Res. Pt. I, 49, 1705–1723, https://doi.org/10.1016/S0967-0637(02)00093-6, 2002.
Moy, A. D., Howard, W. R., Bray, S. G., and Trull, T. W.: Reduced calcification in modern Southern Ocean planktonic foraminifera, Nat. Geosci., 2, 276–280, https://doi.org/10.1038/ngeo460, 2009.
Mucci, A.: The solubility of calcite and aragonite in seawater at various salinities, temperatures, and one atmosphere total pressure, Am. J. Sci., 283, 780–799, https://doi.org/10.2475/ajs.283.7.780, 1983.
Orr, J. C., Fabry, V. J., Aumont, O., Bopp, L., Doney, S. C., Feely, R. A., Gnanadesikan, A., Gruber, N., Ishida, A., Joos, F., Key, R. M., Lindsay, K., Maier-Reimer, E., Matear, R., Monfray, P., Mouchet, A., Najjar, R. G., Plattner, G.-K., Rodgers, K. B., Sabine, C. L., Sarmiento, J. L., Schlitzer, R., Slater, R. D., Totterdell, I. J., and Weirig, M.-F., Yamanaka, Y. and Yool, A.: Anthropogenic ocean acidification over the twenty-first century and its impact on calcifying organisms, Nature, 437, 681–686, https://doi.org/10.1038/nature04095, 2005.
Orsi, A. H. and Wiederwohl, C. L.: A recount of Ross Sea waters, Deep-Sea Res. Pt. II, 56, 778–795, https://doi.org/10.1016/j.dsr2.2008.10.033, 2009.
Orsi, A. H., Whitworth, T., and Nowlin, W. D.: On the meridional extent and fronts of the Antarctic Circumpolar Current, Deep-Sea Res. Pt. I, 42, 641–673, https://doi.org/10.1016/0967-0637(95)00021-W, 1995.
Petty, A. A., Holland, P. R., and Feltham, D. L.: Sea ice and the ocean mixed layer over the Antarctic shelf seas, The Cryosphere, 8, 761–783, https://doi.org/10.5194/tc-8-761-2014, 2014.
Reuer, M. K., Barnett, B. A., Bender, M. L., Falkowski, P. G., and Hendricks, M. B.: New estimates of Southern Ocean biological production rates from O2/Ar ratios and the triple isotope composition of O2, Deep-Sea Res. Pt. I, 54, 951–974, https://doi.org/10.1016/j.dsr.2007.02.007, 2007.
Riebesell, U., Zondervan, I., Rost, B., Tortell, P. D., Zeebe, R. E., and Morel, F. M.: Reduced calcification of marine plankton in response to increased atmospheric CO2, Nature, 407, 364–367, https://doi.org/10.1038/35030078, 2000.
Rintoul, S., Hughes, C., and Olbers, D.: The Antarctic Circumpolar Current System, in: Ocean Circulation and Climate, edited by: Siedler, G., Church, J., and Gould, J., Elsevier, New York, USA, 271–301, 2001.
Rivaro, P., Messa, R., Ianni, C., Magi, E., and Budillon, G.: Distribution of total alkalinity and pH in the Ross Sea (Antarctica) waters during austral summer 2008, Polar Res., 33, 20403, https://doi.org/10.3402/polar.v33.20403, 2014.
Robbins, L. L., Wynn, J. G., Lisle, J. T., Yates, K. K., Knorr, P. O., Byrne, R. H., Liu, X., Patsavas, M. C., Azetsu-Scott, K., and Takahashi, T.: Baseline monitoring of the western Arctic Ocean estimates 20
Roden, N. P., Shadwick, E. H., Tilbrook, B., and Trull, T. W.: Annual cycle of carbonate chemistry and decadal change in coastal Prydz Bay, East Antarctica, Mar. Chem., 155, 135–147, https://doi.org/10.1016/j.marchem.2013.06.006, 2013.
Rubin, S. I.: Carbon and nutrient cycling in the upper water column across the Polar Frontal Zone and Antarctic Circumpolar Current along 170° W, Global Biogeochem. Cy., 17, 1087, https://doi.org/10.1029/2002GB001900, 2003.
Rubin, S. I., Takahashi, T., Chipman, D. W., and Goddard, J. G.: Primary productivity and nutrient utilization ratios in the pacific sector of the Southern Ocean based on seasonal changes in seawater chemistry, Deep-Sea Res. Pt. I, 45, 1211–1234, https://doi.org/10.1016/S0967-0637(98)00021-1, 1998.
Saenz, B. T. and Arrigo, K. R.: Annual primary production in Antarctic sea ice during 2005-2006 from a sea ice state estimate, J. Geophys. Res.-Oceans, 119, 3645–3678, https://doi.org/10.1002/2013JC009677, 2014.
Sandrini, S., Ait-Ameur, N., Rivaro, P., Massolo, S., Touratier, F., Tositti, L., and Goyet, C.: Anthropogenic carbon distribution in the Ross Sea, Antarctica, Antarct. Sci., 19, 395–407, https://doi.org/10.1017/S0954102007000405, 2007.
Schram, J. B., Schoenrock, K. M., McClintock, J. B., Amsler, C. D., and Angus, R. A.: Multi-frequency observations of seawater carbonate chemistry on the central coast of the western Antarctic Peninsula, Polar Res., 1, 1–49, 2015.
Seibel, B. A. and Dierssen, H. M.: Cascading Trophic Impacts of Reduced Biomass in the Ross Sea, Antarctica: Just the Tip of the Iceberg?, Biol. Bull., 205, 93–97, 2003.
Sewell, M. A. and Hofmann, G. E.: Antarctic echinoids and climate change: A major impact on the brooding forms, Glob. Change Biol., 17, 734–744, https://doi.org/10.1111/j.1365-2486.2010.02288.x, 2011.
Shadwick, E. H., Rintoul, S. R., Tilbrook, B., Williams, G. D., Young, N., Fraser, A. D., Marchant, H., Smith, J., and Tamura, T.: Glacier tongue calving reduced dense water formation and enhanced carbon uptake, Geophys. Res. Lett., 40, 904–909, https://doi.org/10.1002/grl.50178, 2013.
Shadwick, E. H., Tilbrook, B., and Williams, G. D.: Carbonate chemistry in the Mertz Polynya (East Antarctica): Biological and physical modification of dense water outflows and the export of anthropogenic CO2, J. Geophys. Res.-Oceans, 119, 1–14, https://doi.org/10.1002/2013JC009286, 2014.
Smith, W., Sedwick, P., Arrigo, K., Ainley, D., and Orsi, A.: The Ross Sea in a Sea of Change, Oceanography, 25, 90–103, https://doi.org/10.5670/oceanog.2012.80, 2012.
Smith, W. O. and Gordon, L. I.: Hyperproductivity of the Ross Sea (Antarctica) polynya during austral spring, Geophys. Res. Lett., 24, 233–236, https://doi.org/10.1029/96GL03926, 1997.
Sokolov, S. and Rintoul, S. R.: Circumpolar structure and distribution of the antarctic circumpolar current fronts: 1. Mean circumpolar paths, J. Geophys. Res.-Oceans, 114, 1–19, https://doi.org/10.1029/2008JC005108, 2009.
Spreen, G., Kaleschke, L., and Heygster, G.: Sea ice remote sensing using AMSR-E 89-GHz channels, J. Geophys. Res.-Oceans, 113, C02S03, https://doi.org/10.1029/2005JC003384, 2008.
Stumpp, M., Hu, M. Y., Melzner, F., Gutowska, M. A., Dorey, N., Himmerkus, N., Holtmann, W. C., Dupont, S. T., Thorndyke, M. C., and Bleich, M.: Acidified seawater impacts sea urchin larvae pH regulatory systems relevant for calcification., P. Natl. Acad. Sci. USA., 109, 18192–18197, https://doi.org/10.1073/pnas.1209174109, 2012.
Suckling, C. C., Clark, M. S., Richard, J., Morley, S. A., Thorne, M. S., Harper, E. M., and Peck, L. S.: Adult acclimation to combined temperature and pH stressors significantly enhances reproductive outcomes compared to short-term exposures, J. Anim. Ecol., 84, 773–784, https://doi.org/10.1111/1365-2656.12316, 2015.
Sweeney, C.: The Annual Cycle of Surface Water CO2 and O2 in the Ross Sea: A model for Gas Exchange on the Continental Shelves of Antarctica, in: Biogeochemistry of the Ross Sea, 295–310. 2003.
Sweeney, C., Hansell, D. A., Carlson, C. A., Codispoti, L. A., Gordon, L. I., Marra, J., Millero, F. J., Smith, W. O., and Takahashi, T.: Biogeochemical regimes, net community production and carbon export in the Ross Sea, Antarctica, Deep-Sea Res. Pt. II., 47, 3369–3394, https://doi.org/10.1016/S0967-0645(00)00072-2, 2000a.
Sweeney, C., Smith, W. O., Hales, B., Bidigare, R. R., Carlson, C. A., Codispoti, L. A., Gordon, L. I., Hansell, D. A., Millero, F. J., Park, M. O., and Takahashi, T.: Nutrient and carbon removal ratios and fluxes in the Ross Sea, Antarctica, Deep-Sea Res. Pt. II, 47, 3395–3421, https://doi.org/10.1016/S0967-0645(00)00073-4, 2000b.
Swift, J. H. and Orsi, A. H.: Sixty-four days of hydrography and storms: RVIB Nathaniel B. Palmer's 2011 SO4P Cruise, Oceanography, 25, 54–55, https://doi.org/10.5670/oceanog.2012.74, 2012.
Tagliabue, A. and Arrigo, K. R.: Iron in the Ross Sea: 1. Impact on CO2 fluxes via variation in phytoplankton functional group and non-Redfield stoichiometry, J. Geophys. Res.-Oceans, 110, 1–15, https://doi.org/10.1029/2004JC002531, 2005.
Takahashi, T., Sutherland, S. C., Wanninkhof, R., Sweeney, C., Feely, R. A., Chipman, D. W., Hales, B., Friederich, G., Chavez, F., Sabine, C., Watson, A., Bakker, D. C. E., Schuster, U., Metzl, N., Yoshikawa-Inoue, H., Ishii, M., Midorikawa, T., Nojiri, Y., Körtzinger, A., Steinhoff, T., Hoppema, M., Olafsson, J., Arnarson, T. S., Tilbrook, B., Johannessen, T., Olsen, A., Bellerby, R., Wong, C. S., Delille, B., Bates, N. R., and de Baar, H. J. W.: Climatological mean and decadal change in surface ocean pCO2, and net sea-air CO2 flux over the global oceans, Deep-Sea Res. Pt II, 56, 554–577, https://doi.org/10.1016/j.dsr2.2008.12.009, 2009.
Takahashi, T., Sweeney, C., Hales, B., Chipman, D., Newberger, T., Goddard, J., Iannuzzi, R., and Sutherland, S.: The Changing Carbon Cycle in the Southern Ocean, Oceanography, 25, 26–37, https://doi.org/10.5670/oceanog.2012.71, 2012.
Tortell, P. D., Payne, C. D., Li, Y., Trimborn, S., Rost, B., Smith, W. O., Riesselman, C., Dunbar, R. B., Sedwick, P., and DiTullio, G. R.: CO2 sensitivity of Southern Ocean phytoplankton, Geophys. Res. Lett., 35, L04605, https://doi.org/10.1029/2007GL032583, 2008.
van Heuven, S., Pierrot, D., Rae, J. W. B., Lewis, E., and Wallace, D. W. R.: MATLAB program developed for CO2 system calculations, ORNL/CDIAC-105b, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, TN, USA, availabe at: http://cdiac.ornl.gov/ftp/co2sys/CO2SYS_calc_MATLAB_v1.1/ (last access: 27 November 2015), 2011.
Weeber, A., Swart, S., and Monteiro, P. M. S.: Seasonality of sea ice controls interannual variability of summertime ΩA at the ice shelf in the Eastern Weddell Sea – an ocean acidification sensitivity study, Biogeosciences Discuss., 12, 1653–1687, https://doi.org/10.5194/bgd-12-1653-2015, 2015.
Yamamoto-Kawai, M., McLaughlin, F. A., Carmack, E. C., Nishino, S., and Shimada, K.: Aragonite undersaturation in the Arctic Ocean: effects of ocean acidification and sea ice melt, Science, 326, 1098–1100, https://doi.org/10.1126/science.1174190, 2009.
Yu, P. C., Sewell, M. A., Matson, P. G., Rivest, E. B., Kapsenberg, L., and Hofmann, G. E.: Growth attenuation with developmental schedule progression in embryos and early larvae of Sterechinus neumayeri raised under elevated CO2, PLoS One, 8, e52448, https://doi.org/10.1371/journal.pone.0052448, 2013.
Short summary
We calculate the carbonate saturation state of surface water from the Ross Sea and along a transect between the Ross Sea and southern Chile using ~ 1700 total alkalinity measurements. Our results suggest that variability in surface carbonate saturation state is driven by biological productivity. We argue that in the Ross Sea the aragonite saturation state of surface water during the early spring never falls below 1.2.
We calculate the carbonate saturation state of surface water from the Ross Sea and along a...
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