Articles | Volume 12, issue 20
https://doi.org/10.5194/bg-12-6085-2015
© 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-12-6085-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Air–water fluxes and sources of carbon dioxide in the Delaware Estuary: spatial and seasonal variability
A. Joesoef
School of Marine Science and Policy, University of Delaware, Newark, Delaware, USA
W.-J. Huang
School of Marine Science and Policy, University of Delaware, Newark, Delaware, USA
present address: Department of Oceanography, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
Y. Gao
School of Marine Science and Policy, University of Delaware, Newark, Delaware, USA
W.-J. Cai
CORRESPONDING AUTHOR
School of Marine Science and Policy, University of Delaware, Newark, Delaware, USA
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In this paper, we focus on key, poorly understood properties of carbonate geochemistry in one of the largest estuaries in North America. We explore how varying environmental factors impact estuarine inorganic carbon fluxes and seasonal net ecosystem production. Comparisons with long-term records highlight the significance of tributary inputs as well as a regional shift towards increased riverine bicarbonate concentrations.
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Li-Qing Jiang, Richard A. Feely, Rik Wanninkhof, Dana Greeley, Leticia Barbero, Simone Alin, Brendan R. Carter, Denis Pierrot, Charles Featherstone, James Hooper, Chris Melrose, Natalie Monacci, Jonathan D. Sharp, Shawn Shellito, Yuan-Yuan Xu, Alex Kozyr, Robert H. Byrne, Wei-Jun Cai, Jessica Cross, Gregory C. Johnson, Burke Hales, Chris Langdon, Jeremy Mathis, Joe Salisbury, and David W. Townsend
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Coastal ecosystems account for most of the economic activities related to commercial and recreational fisheries and aquaculture industries, supporting about 90 % of the global fisheries yield and 80 % of known species of marine fish. Despite the large potential risks from ocean acidification (OA), internally consistent water column OA data products in the coastal ocean still do not exist. This paper is the first time we report a high quality OA data product in North America's coastal waters.
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The biological production and air–sea CO2 exchange in the surface water of the northern Gulf of Mexico during springtime were mainly controlled by the changes in the availability of light and nutrients during the river–ocean mixing process, with strong CO2 uptake occurring in the river plume regions. The slow air–sea CO2 exchange rate and buffering effect of the CO2 system may result in decoupling between biological production and CO2 flux.
Adrienne J. Sutton, Richard A. Feely, Stacy Maenner-Jones, Sylvia Musielwicz, John Osborne, Colin Dietrich, Natalie Monacci, Jessica Cross, Randy Bott, Alex Kozyr, Andreas J. Andersson, Nicholas R. Bates, Wei-Jun Cai, Meghan F. Cronin, Eric H. De Carlo, Burke Hales, Stephan D. Howden, Charity M. Lee, Derek P. Manzello, Michael J. McPhaden, Melissa Meléndez, John B. Mickett, Jan A. Newton, Scott E. Noakes, Jae Hoon Noh, Solveig R. Olafsdottir, Joseph E. Salisbury, Uwe Send, Thomas W. Trull, Douglas C. Vandemark, and Robert A. Weller
Earth Syst. Sci. Data, 11, 421–439, https://doi.org/10.5194/essd-11-421-2019, https://doi.org/10.5194/essd-11-421-2019, 2019
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Long-term observations are critical records for distinguishing natural cycles from climate change. We present a data set of 40 surface ocean CO2 and pH time series that suggests the time length necessary to detect a trend in seawater CO2 due to uptake of atmospheric CO2 varies from 8 years in the least variable ocean regions to 41 years in the most variable coastal regions. This data set provides a tool to evaluate natural cycles of ocean CO2, with long-term trends emerging as records lengthen.
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Biogeosciences, 14, 2441–2468, https://doi.org/10.5194/bg-14-2441-2017, https://doi.org/10.5194/bg-14-2441-2017, 2017
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The C-GEM generic reactive-transport model is applied to each tidal estuary of the US East Coast. Seasonal simulations are performed, which allows the understanding and quantification of the effect of the estuarine filter on the lateral fluxes of carbon coming from rivers.
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Adrienne J. Sutton, Christopher L. Sabine, Richard A. Feely, Wei-Jun Cai, Meghan F. Cronin, Michael J. McPhaden, Julio M. Morell, Jan A. Newton, Jae-Hoon Noh, Sólveig R. Ólafsdóttir, Joseph E. Salisbury, Uwe Send, Douglas C. Vandemark, and Robert A. Weller
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Biogeosciences, 13, 4359–4377, https://doi.org/10.5194/bg-13-4359-2016, https://doi.org/10.5194/bg-13-4359-2016, 2016
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D. C. E. Bakker, B. Pfeil, K. Smith, S. Hankin, A. Olsen, S. R. Alin, C. Cosca, S. Harasawa, A. Kozyr, Y. Nojiri, K. M. O'Brien, U. Schuster, M. Telszewski, B. Tilbrook, C. Wada, J. Akl, L. Barbero, N. R. Bates, J. Boutin, Y. Bozec, W.-J. Cai, R. D. Castle, F. P. Chavez, L. Chen, M. Chierici, K. Currie, H. J. W. de Baar, W. Evans, R. A. Feely, A. Fransson, Z. Gao, B. Hales, N. J. Hardman-Mountford, M. Hoppema, W.-J. Huang, C. W. Hunt, B. Huss, T. Ichikawa, T. Johannessen, E. M. Jones, S. D. Jones, S. Jutterström, V. Kitidis, A. Körtzinger, P. Landschützer, S. K. Lauvset, N. Lefèvre, A. B. Manke, J. T. Mathis, L. Merlivat, N. Metzl, A. Murata, T. Newberger, A. M. Omar, T. Ono, G.-H. Park, K. Paterson, D. Pierrot, A. F. Ríos, C. L. Sabine, S. Saito, J. Salisbury, V. V. S. S. Sarma, R. Schlitzer, R. Sieger, I. Skjelvan, T. Steinhoff, K. F. Sullivan, H. Sun, A. J. Sutton, T. Suzuki, C. Sweeney, T. Takahashi, J. Tjiputra, N. Tsurushima, S. M. A. C. van Heuven, D. Vandemark, P. Vlahos, D. W. R. Wallace, R. Wanninkhof, and A. J. Watson
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W.-J. Huang, W.-J. Cai, Y. Wang, and C. S. Hopkinson
Biogeosciences Discuss., https://doi.org/10.5194/bgd-10-19867-2013, https://doi.org/10.5194/bgd-10-19867-2013, 2013
Revised manuscript has not been submitted
W.-C. Chou, G.-C. Gong, W.-J. Cai, and C.-M. Tseng
Biogeosciences, 10, 3889–3899, https://doi.org/10.5194/bg-10-3889-2013, https://doi.org/10.5194/bg-10-3889-2013, 2013
L. J. Zhang, L. Wang, W.-J. Cai, D. M. Liu, and Z. G. Yu
Biogeosciences, 10, 2513–2524, https://doi.org/10.5194/bg-10-2513-2013, https://doi.org/10.5194/bg-10-2513-2013, 2013
L.-Q. Jiang, W.-J. Cai, Y. Wang, and J. E. Bauer
Biogeosciences, 10, 839–849, https://doi.org/10.5194/bg-10-839-2013, https://doi.org/10.5194/bg-10-839-2013, 2013
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Biogeochemistry: Air - Sea Exchange
Dimethyl sulfide (DMS) climatologies, fluxes, and trends – Part 1: Differences between seawater DMS estimations
Dimethyl sulfide (DMS) climatologies, fluxes, and trends – Part 2: Sea–air fluxes
High-frequency continuous measurements reveal strong diel and seasonal cycling of pCO2 and CO2 flux in a mesohaline reach of the Chesapeake Bay
Significant role of physical transport in the marine carbon monoxide (CO) cycle: observations in the East Sea (Sea of Japan), the western North Pacific, and the Bering Sea in summer
Central Arctic Ocean surface–atmosphere exchange of CO2 and CH4 constrained by direct measurements
Spatial and seasonal variability in volatile organic sulfur compounds in seawater and the overlying atmosphere of the Bohai and Yellow seas
Estimating marine carbon uptake in the northeast Pacific using a neural network approach
Sea–air methane flux estimates derived from marine surface observations and instantaneous atmospheric measurements in the northern Labrador Sea and Baffin Bay
Global analysis of the controls on seawater dimethylsulfide spatial variability
Air–sea gas exchange in a seagrass ecosystem – results from a 3He ∕ SF6 tracer release experiment
Concentrations of dissolved dimethyl sulfide (DMS), methanethiol and other trace gases in context of microbial communities from the temperate Atlantic to the Arctic Ocean
Marine nitrogen fixation as a possible source of atmospheric water-soluble organic nitrogen aerosols in the subtropical North Pacific
Ice nucleating properties of the sea ice diatom Fragilariopsis cylindrus and its exudates
On physical mechanisms enhancing air–sea CO2 exchange
Winter season Southern Ocean distributions of climate-relevant trace gases
How biogenic polymers control surfactant dynamics in the surface microlayer: insights from a coastal Baltic Sea study
Identifying the biological control of the annual and multi-year variations in South Atlantic air–sea CO2 flux
The sensitivity of pCO2 reconstructions to sampling scales across a Southern Ocean sub-domain: a semi-idealized ocean sampling simulation approach
Physical mechanisms for biological carbon uptake during the onset of the spring phytoplankton bloom in the northwestern Mediterranean Sea (BOUSSOLE site)
Wintertime process study of the North Brazil Current rings reveals the region as a larger sink for CO2 than expected
New constraints on biological production and mixing processes in the South China Sea from triple isotope composition of dissolved oxygen
Tidal mixing of estuarine and coastal waters in the western English Channel is a control on spatial and temporal variability in seawater CO2
A seamless ensemble-based reconstruction of surface ocean pCO2 and air–sea CO2 fluxes over the global coastal and open oceans
Sea ice concentration impacts dissolved organic gases in the Canadian Arctic
Evaluating the Arabian Sea as a regional source of atmospheric CO2: seasonal variability and drivers
An empirical MLR for estimating surface layer DIC and a comparative assessment to other gap-filling techniques for ocean carbon time series
Derivation of seawater pCO2 from net community production identifies the South Atlantic Ocean as a CO2 source
Eukaryotic community composition in the sea surface microlayer across an east–west transect in the Mediterranean Sea
Enhancement of the North Atlantic CO2 sink by Arctic Waters
Global ocean dimethyl sulfide climatology estimated from observations and an artificial neural network
Atmospheric deposition of organic matter at a remote site in the central Mediterranean Sea: implications for the marine ecosystem
Underway seawater and atmospheric measurements of volatile organic compounds in the Southern Ocean
Dimethylsulfide (DMS), marine biogenic aerosols and the ecophysiology of coral reefs
Spatial variations in CO2 fluxes in the Saguenay Fjord (Quebec, Canada) and results of a water mixing model
Gas exchange estimates in the Peruvian upwelling regime biased by multi-day near-surface stratification
Insights from year-long measurements of air–water CH4 and CO2 exchange in a coastal environment
On the role of climate modes in modulating the air–sea CO2 fluxes in eastern boundary upwelling systems
Reviews and syntheses: the GESAMP atmospheric iron deposition model intercomparison study
Increase of dissolved inorganic carbon and decrease in pH in near-surface waters in the Mediterranean Sea during the past two decades
Utilizing the Drake Passage Time-series to understand variability and change in subpolar Southern Ocean pCO2
Effect of wind speed on the size distribution of gel particles in the sea surface microlayer: insights from a wind–wave channel experiment
The seasonal cycle of pCO2 and CO2 fluxes in the Southern Ocean: diagnosing anomalies in CMIP5 Earth system models
Marine phytoplankton stoichiometry mediates nonlinear interactions between nutrient supply, temperature, and atmospheric CO2
Interannual drivers of the seasonal cycle of CO2 in the Southern Ocean
Constraints on global oceanic emissions of N2O from observations and models
Arctic Ocean CO2 uptake: an improved multiyear estimate of the air–sea CO2 flux incorporating chlorophyll a concentrations
Uncertainty in the global oceanic CO2 uptake induced by wind forcing: quantification and spatial analysis
Phytoplankton growth response to Asian dust addition in the northwest Pacific Ocean versus the Yellow Sea
Global high-resolution monthly pCO2 climatology for the coastal ocean derived from neural network interpolation
Changes in the partial pressure of carbon dioxide in the Mauritanian–Cap Vert upwelling region between 2005 and 2012
Sankirna D. Joge, Anoop S. Mahajan, Shrivardhan Hulswar, Christa A. Marandino, Martí Galí, Thomas G. Bell, and Rafel Simó
Biogeosciences, 21, 4439–4452, https://doi.org/10.5194/bg-21-4439-2024, https://doi.org/10.5194/bg-21-4439-2024, 2024
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Dimethyl sulfide (DMS) is the largest natural source of sulfur in the atmosphere and leads to the formation of cloud condensation nuclei. DMS emission and quantification of its impacts have large uncertainties, but a detailed study on the emissions and drivers of their uncertainty is missing to date. The emissions are usually calculated from the seawater DMS concentrations and a flux parameterization. Here we quantify the differences in DMS seawater products, which can affect DMS fluxes.
Sankirna D. Joge, Anoop S. Mahajan, Shrivardhan Hulswar, Christa A. Marandino, Martí Galí, Thomas G. Bell, Mingxi Yang, and Rafel Simó
Biogeosciences, 21, 4453–4467, https://doi.org/10.5194/bg-21-4453-2024, https://doi.org/10.5194/bg-21-4453-2024, 2024
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Dimethyl sulfide (DMS) is the largest natural source of sulfur in the atmosphere and leads to the formation of cloud condensation nuclei. DMS emissions and quantification of their impacts have large uncertainties, but a detailed study on the range of emissions and drivers of their uncertainty is missing to date. The emissions are calculated from the seawater DMS concentrations and a flux parameterization. Here we quantify the differences in the effect of flux parameterizations used in models.
A. Whitman Miller, Jim R. Muirhead, Amanda C. Reynolds, Mark S. Minton, and Karl J. Klug
Biogeosciences, 21, 3717–3734, https://doi.org/10.5194/bg-21-3717-2024, https://doi.org/10.5194/bg-21-3717-2024, 2024
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High frequency pCO2 measurements reveal net neutral CO2 flux in a mesohaline reach of the Chesapeake Bay. Net off-gassing to the atmosphere begins in June when water temperatures rise above ~26ºC, continuing through November when temperatures fall below ~10ºC. Dissolved CO2 concentrations follow day–night cycles and are especially pronounced in warm waters. From December through May, the river is largely an uninterrupted sink for CO2 (i.e. CO2 is drawn out of the atmosphere into the river).
Young Shin Kwon, Tae Siek Rhee, Hyun-Cheol Kim, and Hyoun-Woo Kang
Biogeosciences, 21, 1847–1865, https://doi.org/10.5194/bg-21-1847-2024, https://doi.org/10.5194/bg-21-1847-2024, 2024
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Delving into CO dynamics from the East Sea to the Bering Sea, our study unveils the influence of physical transport on CO budgets. By measuring CO concentrations and parameters, we elucidate the interplay between biological and physical processes, highlighting the role of lateral transport in shaping CO distributions. Our findings underscore the importance of considering both biogeochemical and physical drivers in understanding marine carbon fluxes.
John Prytherch, Sonja Murto, Ian Brown, Adam Ulfsbo, Brett F. Thornton, Volker Brüchert, Michael Tjernström, Anna Lunde Hermansson, Amanda T. Nylund, and Lina A. Holthusen
Biogeosciences, 21, 671–688, https://doi.org/10.5194/bg-21-671-2024, https://doi.org/10.5194/bg-21-671-2024, 2024
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We directly measured methane and carbon dioxide exchange between ocean or sea ice and the atmosphere during an icebreaker-based expedition to the central Arctic Ocean (CAO) in summer 2021. These measurements can help constrain climate models and carbon budgets. The methane measurements, the first such made in the CAO, are lower than previous estimates and imply that the CAO is an insignificant contributor to Arctic methane emission. Gas exchange rates are slower than previous estimates.
Juan Yu, Lei Yu, Zhen He, Gui-Peng Yang, Jing-Guang Lai, and Qian Liu
Biogeosciences, 21, 161–176, https://doi.org/10.5194/bg-21-161-2024, https://doi.org/10.5194/bg-21-161-2024, 2024
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The distributions of volatile organic sulfur compounds (VSCs) (DMS, COS, and CS2) in the seawater and atmosphere of the Bohai and Yellow Seas were evaluated. Seasonal variations in VSCs were found and showed summer > spring. The COS concentrations exhibited positive correlation with DOC concentrations in seawater during summer. VSCs concentrations in seawater decreased with the depth. Sea-to-air fluxes of COS, DMS, and CS2 indicated that these marginal seas are sources of atmospheric VSCs.
Patrick J. Duke, Roberta C. Hamme, Debby Ianson, Peter Landschützer, Mohamed M. M. Ahmed, Neil C. Swart, and Paul A. Covert
Biogeosciences, 20, 3919–3941, https://doi.org/10.5194/bg-20-3919-2023, https://doi.org/10.5194/bg-20-3919-2023, 2023
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The ocean is both impacted by climate change and helps mitigate its effects through taking up carbon from the atmosphere. We used a machine learning approach to investigate what controls open-ocean carbon uptake in the northeast Pacific open ocean. Marine heatwaves that lasted 2–3 years increased uptake, while the upwelling strength of the Alaskan Gyre controlled uptake over 10-year time periods. The trend from 1998–2019 suggests carbon uptake in the northeast Pacific open ocean is increasing.
Judith Vogt, David Risk, Evelise Bourlon, Kumiko Azetsu-Scott, Evan N. Edinger, and Owen A. Sherwood
Biogeosciences, 20, 1773–1787, https://doi.org/10.5194/bg-20-1773-2023, https://doi.org/10.5194/bg-20-1773-2023, 2023
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The release of the greenhouse gas methane from Arctic submarine sources could exacerbate climate change in a positive feedback. Continuous monitoring of atmospheric methane levels over a 5100 km voyage in the western margin of the Labrador Sea and Baffin Bay revealed above-global averages likely affected by both onshore and offshore methane sources. Instantaneous sea–air methane fluxes were near zero at all measured stations, including a persistent cold-seep location.
George Manville, Thomas G. Bell, Jane P. Mulcahy, Rafel Simó, Martí Galí, Anoop S. Mahajan, Shrivardhan Hulswar, and Paul R. Halloran
Biogeosciences, 20, 1813–1828, https://doi.org/10.5194/bg-20-1813-2023, https://doi.org/10.5194/bg-20-1813-2023, 2023
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We present the first global investigation of controls on seawater dimethylsulfide (DMS) spatial variability over scales of up to 100 km. Sea surface height anomalies, density, and chlorophyll a help explain almost 80 % of DMS variability. The results suggest that physical and biogeochemical processes play an equally important role in controlling DMS variability. These data provide independent confirmation that existing parameterisations of seawater DMS concentration use appropriate variables.
Ryo Dobashi and David T. Ho
Biogeosciences, 20, 1075–1087, https://doi.org/10.5194/bg-20-1075-2023, https://doi.org/10.5194/bg-20-1075-2023, 2023
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Seagrass meadows are productive ecosystems and bury much carbon. Understanding their role in the global carbon cycle requires knowledge of air–sea CO2 fluxes and hence the knowledge of gas transfer velocity (k). In this study, k was determined from the dual tracer technique in Florida Bay. The observed gas transfer velocity was lower than previous studies in the coastal and open oceans at the same wind speeds, most likely due to wave attenuation by seagrass and limited wind fetch in this area.
Valérie Gros, Bernard Bonsang, Roland Sarda-Estève, Anna Nikolopoulos, Katja Metfies, Matthias Wietz, and Ilka Peeken
Biogeosciences, 20, 851–867, https://doi.org/10.5194/bg-20-851-2023, https://doi.org/10.5194/bg-20-851-2023, 2023
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The oceans are both sources and sinks for trace gases important for atmospheric chemistry and marine ecology. Here, we quantified selected trace gases (including the biological metabolites dissolved dimethyl sulfide, methanethiol and isoprene) along a 2500 km transect from the North Atlantic to the Arctic Ocean. In the context of phytoplankton and bacterial communities, our study suggests that methanethiol (rarely measured before) might substantially influence ocean–atmosphere cycling.
Tsukasa Dobashi, Yuzo Miyazaki, Eri Tachibana, Kazutaka Takahashi, Sachiko Horii, Fuminori Hashihama, Saori Yasui-Tamura, Yoko Iwamoto, Shu-Kuan Wong, and Koji Hamasaki
Biogeosciences, 20, 439–449, https://doi.org/10.5194/bg-20-439-2023, https://doi.org/10.5194/bg-20-439-2023, 2023
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Water-soluble organic nitrogen (WSON) in marine aerosols is important for biogeochemical cycling of bioelements. Our shipboard measurements suggested that reactive nitrogen produced and exuded by nitrogen-fixing microorganisms in surface seawater likely contributed to the formation of WSON aerosols in the subtropical North Pacific. This study provides new implications for the role of marine microbial activity in the formation of WSON aerosols in the ocean surface.
Lukas Eickhoff, Maddalena Bayer-Giraldi, Naama Reicher, Yinon Rudich, and Thomas Koop
Biogeosciences, 20, 1–14, https://doi.org/10.5194/bg-20-1-2023, https://doi.org/10.5194/bg-20-1-2023, 2023
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The formation of ice is an important process in Earth’s atmosphere, biosphere, and cryosphere, in particular in polar regions. Our research focuses on the influence of the sea ice diatom Fragilariopsis cylindrus and of molecules produced by it upon heterogenous ice nucleation. For that purpose, we studied the freezing of tiny droplets containing the diatoms in a microfluidic device. Together with previous studies, our results suggest a common freezing behaviour of various sea ice diatoms.
Lucía Gutiérrez-Loza, Erik Nilsson, Marcus B. Wallin, Erik Sahlée, and Anna Rutgersson
Biogeosciences, 19, 5645–5665, https://doi.org/10.5194/bg-19-5645-2022, https://doi.org/10.5194/bg-19-5645-2022, 2022
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The exchange of CO2 between the ocean and the atmosphere is an essential aspect of the global carbon cycle and is highly relevant for the Earth's climate. In this study, we used 9 years of in situ measurements to evaluate the temporal variability in the air–sea CO2 fluxes in the Baltic Sea. Furthermore, using this long record, we assessed the effect of atmospheric and water-side mechanisms controlling the efficiency of the air–sea CO2 exchange under different wind-speed conditions.
Li Zhou, Dennis Booge, Miming Zhang, and Christa A. Marandino
Biogeosciences, 19, 5021–5040, https://doi.org/10.5194/bg-19-5021-2022, https://doi.org/10.5194/bg-19-5021-2022, 2022
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Trace gas air–sea exchange exerts an important control on air quality and climate, especially in the Southern Ocean (SO). Almost all of the measurements there are skewed to summer, but it is essential to expand our measurement database over greater temporal and spatial scales. Therefore, we report measured concentrations of dimethylsulfide (DMS, as well as related sulfur compounds) and isoprene in the Atlantic sector of the SO. The observations of isoprene are the first in the winter in the SO.
Theresa Barthelmeß and Anja Engel
Biogeosciences, 19, 4965–4992, https://doi.org/10.5194/bg-19-4965-2022, https://doi.org/10.5194/bg-19-4965-2022, 2022
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Greenhouse gases released by human activity cause a global rise in mean temperatures. While scientists can predict how much of these gases accumulate in the atmosphere based on not only human-derived sources but also oceanic sinks, it is rather difficult to predict the major influence of coastal ecosystems. We provide a detailed study on the occurrence, composition, and controls of substances that suppress gas exchange. We thus help to determine what controls coastal greenhouse gas fluxes.
Daniel J. Ford, Gavin H. Tilstone, Jamie D. Shutler, and Vassilis Kitidis
Biogeosciences, 19, 4287–4304, https://doi.org/10.5194/bg-19-4287-2022, https://doi.org/10.5194/bg-19-4287-2022, 2022
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This study explores the seasonal, inter-annual, and multi-year drivers of the South Atlantic air–sea CO2 flux. Our analysis showed seasonal sea surface temperatures dominate in the subtropics, and the subpolar regions correlated with biological processes. Inter-annually, the El Niño–Southern Oscillation correlated with the CO2 flux by modifying sea surface temperatures and biological activity. Long-term trends indicated an important biological contribution to changes in the air–sea CO2 flux.
Laique M. Djeutchouang, Nicolette Chang, Luke Gregor, Marcello Vichi, and Pedro M. S. Monteiro
Biogeosciences, 19, 4171–4195, https://doi.org/10.5194/bg-19-4171-2022, https://doi.org/10.5194/bg-19-4171-2022, 2022
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Based on observing system simulation experiments using a mesoscale-resolving model, we found that to significantly improve uncertainties and biases in carbon dioxide (CO2) mapping in the Southern Ocean, it is essential to resolve the seasonal cycle (SC) of the meridional gradient of CO2 through high frequency (at least daily) observations that also span the region's meridional axis. We also showed that the estimated SC anomaly and mean annual CO2 are highly sensitive to seasonal sampling biases.
Liliane Merlivat, Michael Hemming, Jacqueline Boutin, David Antoine, Vincenzo Vellucci, Melek Golbol, Gareth A. Lee, and Laurence Beaumont
Biogeosciences, 19, 3911–3920, https://doi.org/10.5194/bg-19-3911-2022, https://doi.org/10.5194/bg-19-3911-2022, 2022
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We use in situ high-temporal-resolution measurements of dissolved inorganic carbon and atmospheric parameters at the air–sea interface to analyse phytoplankton bloom initiation identified as the net rate of biological carbon uptake in the Mediterranean Sea. The shift from wind-driven to buoyancy-driven mixing creates conditions for blooms to begin. Active mixing at the air–sea interface leads to the onset of the surface phytoplankton bloom due to the relaxation of wind speed following storms.
Léa Olivier, Jacqueline Boutin, Gilles Reverdin, Nathalie Lefèvre, Peter Landschützer, Sabrina Speich, Johannes Karstensen, Matthieu Labaste, Christophe Noisel, Markus Ritschel, Tobias Steinhoff, and Rik Wanninkhof
Biogeosciences, 19, 2969–2988, https://doi.org/10.5194/bg-19-2969-2022, https://doi.org/10.5194/bg-19-2969-2022, 2022
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We investigate the impact of the interactions between eddies and the Amazon River plume on the CO2 air–sea fluxes to better characterize the ocean carbon sink in winter 2020. The region is a strong CO2 sink, previously underestimated by a factor of 10 due to a lack of data and understanding of the processes responsible for the variability in ocean carbon parameters. The CO2 absorption is mainly driven by freshwater from the Amazon entrained by eddies and by the winter seasonal cooling.
Hana Jurikova, Osamu Abe, Fuh-Kwo Shiah, and Mao-Chang Liang
Biogeosciences, 19, 2043–2058, https://doi.org/10.5194/bg-19-2043-2022, https://doi.org/10.5194/bg-19-2043-2022, 2022
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We studied the isotopic composition of oxygen dissolved in seawater in the South China Sea. This tells us about the origin of oxygen in the water column, distinguishing between biological oxygen produced by phytoplankton communities and atmospheric oxygen entering seawater through gas exchange. We found that the East Asian Monsoon plays an important role in determining the amount of oxygen produced vs. consumed by the phytoplankton, as well as in inducing vertical water mass mixing.
Richard P. Sims, Michael Bedington, Ute Schuster, Andrew J. Watson, Vassilis Kitidis, Ricardo Torres, Helen S. Findlay, James R. Fishwick, Ian Brown, and Thomas G. Bell
Biogeosciences, 19, 1657–1674, https://doi.org/10.5194/bg-19-1657-2022, https://doi.org/10.5194/bg-19-1657-2022, 2022
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The amount of carbon dioxide (CO2) being absorbed by the ocean is relevant to the earth's climate. CO2 values in the coastal ocean and estuaries are not well known because of the instrumentation used. We used a new approach to measure CO2 across the coastal and estuarine zone. We found that CO2 and salinity were linked to the state of the tide. We used our CO2 measurements and model salinity to predict CO2. Previous studies overestimate how much CO2 the coastal ocean draws down at our site.
Thi Tuyet Trang Chau, Marion Gehlen, and Frédéric Chevallier
Biogeosciences, 19, 1087–1109, https://doi.org/10.5194/bg-19-1087-2022, https://doi.org/10.5194/bg-19-1087-2022, 2022
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Air–sea CO2 fluxes and associated uncertainty over the open ocean to coastal shelves are estimated with a new ensemble-based reconstruction of pCO2 trained on observation-based data. The regional distribution and seasonality of CO2 sources and sinks are consistent with those suggested in previous studies as well as mechanisms discussed therein. The ensemble-based uncertainty field allows identifying critical regions where improvements in pCO2 and air–sea CO2 flux estimates should be a priority.
Charel Wohl, Anna E. Jones, William T. Sturges, Philip D. Nightingale, Brent Else, Brian J. Butterworth, and Mingxi Yang
Biogeosciences, 19, 1021–1045, https://doi.org/10.5194/bg-19-1021-2022, https://doi.org/10.5194/bg-19-1021-2022, 2022
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We measured concentrations of five different organic gases in seawater in the high Arctic during summer. We found higher concentrations near the surface of the water column (top 5–10 m) and in areas of partial ice cover. This suggests that sea ice influences the concentrations of these gases. These gases indirectly exert a slight cooling effect on the climate, and it is therefore important to measure the levels accurately for future climate predictions.
Alain de Verneil, Zouhair Lachkar, Shafer Smith, and Marina Lévy
Biogeosciences, 19, 907–929, https://doi.org/10.5194/bg-19-907-2022, https://doi.org/10.5194/bg-19-907-2022, 2022
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The Arabian Sea is a natural CO2 source to the atmosphere, but previous work highlights discrepancies between data and models in estimating air–sea CO2 flux. In this study, we use a regional ocean model, achieve a flux closer to available data, and break down the seasonal cycles that impact it, with one result being the great importance of monsoon winds. As demonstrated in a meta-analysis, differences from data still remain, highlighting the great need for further regional data collection.
Jesse M. Vance, Kim Currie, John Zeldis, Peter W. Dillingham, and Cliff S. Law
Biogeosciences, 19, 241–269, https://doi.org/10.5194/bg-19-241-2022, https://doi.org/10.5194/bg-19-241-2022, 2022
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Long-term monitoring is needed to detect changes in our environment. Time series of ocean carbon have aided our understanding of seasonal cycles and provided evidence for ocean acidification. Data gaps are inevitable, yet no standard method for filling gaps exists. We present a regression approach here and compare it to seven other common methods to understand the impact of different approaches when assessing seasonal to climatic variability in ocean carbon.
Daniel J. Ford, Gavin H. Tilstone, Jamie D. Shutler, and Vassilis Kitidis
Biogeosciences, 19, 93–115, https://doi.org/10.5194/bg-19-93-2022, https://doi.org/10.5194/bg-19-93-2022, 2022
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This study identifies the most accurate biological proxy for the estimation of seawater pCO2 fields, which are key to assessing the ocean carbon sink. Our analysis shows that the net community production (NCP), the balance between photosynthesis and respiration, was more accurate than chlorophyll a within a neural network scheme. The improved pCO2 estimates, based on NCP, identified the South Atlantic Ocean as a net CO2 source, compared to a CO2 sink using chlorophyll a.
Birthe Zäncker, Michael Cunliffe, and Anja Engel
Biogeosciences, 18, 2107–2118, https://doi.org/10.5194/bg-18-2107-2021, https://doi.org/10.5194/bg-18-2107-2021, 2021
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Fungi are found in numerous marine environments. Our study found an increased importance of fungi in the Ionian Sea, where bacterial and phytoplankton counts were reduced, but organic matter was still available, suggesting fungi might benefit from the reduced competition from bacteria in low-nutrient, low-chlorophyll (LNLC) regions.
Jon Olafsson, Solveig R. Olafsdottir, Taro Takahashi, Magnus Danielsen, and Thorarinn S. Arnarson
Biogeosciences, 18, 1689–1701, https://doi.org/10.5194/bg-18-1689-2021, https://doi.org/10.5194/bg-18-1689-2021, 2021
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The Atlantic north of 50° N is an intense ocean sink area for atmospheric CO2. Observations in the vicinity of Iceland reveal a previously unrecognized Arctic contribution to the North Atlantic CO2 sink. Sustained CO2 influx to waters flowing from the Arctic Ocean is linked to their excess alkalinity derived from sources in the changing Arctic. The results relate to the following question: will the North Atlantic continue to absorb CO2 in the future as it has in the past?
Wei-Lei Wang, Guisheng Song, François Primeau, Eric S. Saltzman, Thomas G. Bell, and J. Keith Moore
Biogeosciences, 17, 5335–5354, https://doi.org/10.5194/bg-17-5335-2020, https://doi.org/10.5194/bg-17-5335-2020, 2020
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Dimethyl sulfide, a volatile compound produced as a byproduct of marine phytoplankton activity, can be emitted to the atmosphere via gas exchange. In the atmosphere, DMS is oxidized to cloud condensation nuclei, thus contributing to cloud formation. Therefore, oceanic DMS plays an important role in regulating the planet's climate by influencing the radiation budget. In this study, we use an artificial neural network model to update the global DMS climatology and estimate the sea-to-air flux.
Yuri Galletti, Silvia Becagli, Alcide di Sarra, Margherita Gonnelli, Elvira Pulido-Villena, Damiano M. Sferlazzo, Rita Traversi, Stefano Vestri, and Chiara Santinelli
Biogeosciences, 17, 3669–3684, https://doi.org/10.5194/bg-17-3669-2020, https://doi.org/10.5194/bg-17-3669-2020, 2020
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This paper reports the first data about atmospheric deposition of dissolved organic matter (DOM) on the island of Lampedusa. It also shows the implications for the surface marine layer by studying the impact of atmospheric organic carbon deposition in the marine ecosystem. It is a preliminary study, but it is pioneering and important for having new data that can be crucial in order to understand the impact of atmospheric deposition on the marine carbon cycle in a global climate change scenario.
Charel Wohl, Ian Brown, Vassilis Kitidis, Anna E. Jones, William T. Sturges, Philip D. Nightingale, and Mingxi Yang
Biogeosciences, 17, 2593–2619, https://doi.org/10.5194/bg-17-2593-2020, https://doi.org/10.5194/bg-17-2593-2020, 2020
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The oceans represent a poorly understood source of organic carbon to the atmosphere. In this paper, we present ship-based measurements of specific compounds in ambient air and seawater of the Southern Ocean. We present fluxes of these gases between air and sea at very high resolution. The data also contain evidence for day and night variations in some of these compounds. These measurements can be used to better understand the role of the Southern Ocean in the cycling of these compounds.
Rebecca L. Jackson, Albert J. Gabric, Roger Cropp, and Matthew T. Woodhouse
Biogeosciences, 17, 2181–2204, https://doi.org/10.5194/bg-17-2181-2020, https://doi.org/10.5194/bg-17-2181-2020, 2020
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Coral reefs are a strong source of atmospheric sulfur through stress-induced emissions of dimethylsulfide (DMS). This biogenic sulfur can influence aerosol and cloud properties and, consequently, the radiative balance over the ocean. DMS emissions may therefore help to mitigate coral physiological stress via increased low-level cloud cover and reduced sea surface temperature. The importance of DMS in coral physiology and climate is reviewed and the implications for coral bleaching are discussed.
Louise Delaigue, Helmuth Thomas, and Alfonso Mucci
Biogeosciences, 17, 547–566, https://doi.org/10.5194/bg-17-547-2020, https://doi.org/10.5194/bg-17-547-2020, 2020
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This paper reports on the first compilation and analysis of the surface water pCO2 distribution in the Saguenay Fjord, the southernmost subarctic fjord in the Northern Hemisphere, and thus fills a significant knowledge gap in current regional estimates of estuarine CO2 emissions.
Tim Fischer, Annette Kock, Damian L. Arévalo-Martínez, Marcus Dengler, Peter Brandt, and Hermann W. Bange
Biogeosciences, 16, 2307–2328, https://doi.org/10.5194/bg-16-2307-2019, https://doi.org/10.5194/bg-16-2307-2019, 2019
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We investigated air–sea gas exchange in oceanic upwelling regions for the case of nitrous oxide off Peru. In this region, routine concentration measurements from ships at 5 m or 10 m depth prove to overestimate surface (bulk) concentration. Thus, standard estimates of gas exchange will show systematic error. This is due to very shallow stratified layers that inhibit exchange between surface water and waters below and can exist for several days. Maximum bias occurs in moderate wind conditions.
Mingxi Yang, Thomas G. Bell, Ian J. Brown, James R. Fishwick, Vassilis Kitidis, Philip D. Nightingale, Andrew P. Rees, and Timothy J. Smyth
Biogeosciences, 16, 961–978, https://doi.org/10.5194/bg-16-961-2019, https://doi.org/10.5194/bg-16-961-2019, 2019
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We quantify the emissions and uptake of the greenhouse gases carbon dioxide and methane from the coastal seas of the UK over 1 year using the state-of-the-art eddy covariance technique. Our measurements show how these air–sea fluxes vary twice a day (tidal), diurnally (circadian) and seasonally. We also estimate the air–sea gas transfer velocity, which is essential for modelling and predicting coastal air-sea exchange.
Riley X. Brady, Nicole S. Lovenduski, Michael A. Alexander, Michael Jacox, and Nicolas Gruber
Biogeosciences, 16, 329–346, https://doi.org/10.5194/bg-16-329-2019, https://doi.org/10.5194/bg-16-329-2019, 2019
Stelios Myriokefalitakis, Akinori Ito, Maria Kanakidou, Athanasios Nenes, Maarten C. Krol, Natalie M. Mahowald, Rachel A. Scanza, Douglas S. Hamilton, Matthew S. Johnson, Nicholas Meskhidze, Jasper F. Kok, Cecile Guieu, Alex R. Baker, Timothy D. Jickells, Manmohan M. Sarin, Srinivas Bikkina, Rachel Shelley, Andrew Bowie, Morgane M. G. Perron, and Robert A. Duce
Biogeosciences, 15, 6659–6684, https://doi.org/10.5194/bg-15-6659-2018, https://doi.org/10.5194/bg-15-6659-2018, 2018
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The first atmospheric iron (Fe) deposition model intercomparison is presented in this study, as a result of the deliberations of the United Nations Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP; http://www.gesamp.org/) Working Group 38. We conclude that model diversity over remote oceans reflects uncertainty in the Fe content parameterizations of dust aerosols, combustion aerosol emissions and the size distribution of transported aerosol Fe.
Liliane Merlivat, Jacqueline Boutin, David Antoine, Laurence Beaumont, Melek Golbol, and Vincenzo Vellucci
Biogeosciences, 15, 5653–5662, https://doi.org/10.5194/bg-15-5653-2018, https://doi.org/10.5194/bg-15-5653-2018, 2018
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The fugacity of carbon dioxide in seawater (fCO2) was measured hourly in the surface waters of the NW Mediterranean Sea during two 3-year sequences separated by 18 years. A decrease of pH of 0.0022 yr−1 was computed. About 85 % of the accumulation of dissolved inorganic carbon (DIC) comes from chemical equilibration with increasing atmospheric CO2; the remaining 15 % accumulation is consistent with estimates of transfer of Atlantic waters through the Gibraltar Strait.
Amanda R. Fay, Nicole S. Lovenduski, Galen A. McKinley, David R. Munro, Colm Sweeney, Alison R. Gray, Peter Landschützer, Britton B. Stephens, Taro Takahashi, and Nancy Williams
Biogeosciences, 15, 3841–3855, https://doi.org/10.5194/bg-15-3841-2018, https://doi.org/10.5194/bg-15-3841-2018, 2018
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The Southern Ocean is highly under-sampled and since this region dominates the ocean sink for CO2, understanding change is critical. Here we utilize available observations to evaluate how the seasonal cycle, variability, and trends in surface ocean carbon in the well-sampled Drake Passage region compare to that of the broader subpolar Southern Ocean. Results indicate that the Drake Passage is representative of the broader region; however, additional winter observations would improve comparisons.
Cui-Ci Sun, Martin Sperling, and Anja Engel
Biogeosciences, 15, 3577–3589, https://doi.org/10.5194/bg-15-3577-2018, https://doi.org/10.5194/bg-15-3577-2018, 2018
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Biogenic gel particles such as transparent exopolymer particles (TEP) and Coomassie stainable particles (CSP) are important components in the sea-surface microlayer (SML). Their potential role in air–sea gas exchange and in primary organic aerosol emission has generated considerable research interest. Our wind wave channel experiment revealed how wind speed controls the accumulation and size distribution of biogenic gel particles in the SML.
N. Precious Mongwe, Marcello Vichi, and Pedro M. S. Monteiro
Biogeosciences, 15, 2851–2872, https://doi.org/10.5194/bg-15-2851-2018, https://doi.org/10.5194/bg-15-2851-2018, 2018
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Here we analyze seasonal cycle of CO2 biases in 10 CMIP5 models in the SO. We find two main model biases; exaggeration of primary production such that biologically driven DIC changes mainly regulates FCO2 variability, and an overestimation of the role of solubility, such that changes in temperature dominantly drive FCO2 seasonal changes to an extent of opposing biological CO2 uptake in spring. CMIP5 models show greater zonal homogeneity in the seasonal cycle of FCO2 than observational products.
Allison R. Moreno, George I. Hagstrom, Francois W. Primeau, Simon A. Levin, and Adam C. Martiny
Biogeosciences, 15, 2761–2779, https://doi.org/10.5194/bg-15-2761-2018, https://doi.org/10.5194/bg-15-2761-2018, 2018
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To bridge the missing links between variable marine elemental stoichiometry, phytoplankton physiology and carbon cycling, we embed four environmentally controlled stoichiometric models into a five-box ocean model. As predicted each model varied in its influence on the biological pump. Surprisingly, we found that variation can lead to nonlinear controls on atmospheric CO2 and carbon export, suggesting the need for further studies of ocean C : P and the impact on ocean carbon cycling.
Luke Gregor, Schalk Kok, and Pedro M. S. Monteiro
Biogeosciences, 15, 2361–2378, https://doi.org/10.5194/bg-15-2361-2018, https://doi.org/10.5194/bg-15-2361-2018, 2018
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The Southern Ocean accounts for a large portion of the variability in oceanic CO2 uptake. However, the drivers of these changes are not understood due to a lack of observations. In this study, we used an ensemble of gap-filling methods to estimate surface CO2. We found that winter was a more important driver of longer-term variability driven by changes in wind stress. Summer variability of CO2 was driven primarily by increases in primary production.
Erik T. Buitenhuis, Parvadha Suntharalingam, and Corinne Le Quéré
Biogeosciences, 15, 2161–2175, https://doi.org/10.5194/bg-15-2161-2018, https://doi.org/10.5194/bg-15-2161-2018, 2018
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Thanks to decreases in CFC concentrations, N2O is now the third-most important greenhouse gas, and the dominant contributor to stratospheric ozone depletion. Here we estimate the ocean–atmosphere N2O flux. We find that an estimate based on observations alone has a large uncertainty. By combining observations and a range of model simulations we find that the uncertainty is much reduced to 2.45 ± 0.8 Tg N yr−1, and better constrained and at the lower end of the estimate in the latest IPCC report.
Sayaka Yasunaka, Eko Siswanto, Are Olsen, Mario Hoppema, Eiji Watanabe, Agneta Fransson, Melissa Chierici, Akihiko Murata, Siv K. Lauvset, Rik Wanninkhof, Taro Takahashi, Naohiro Kosugi, Abdirahman M. Omar, Steven van Heuven, and Jeremy T. Mathis
Biogeosciences, 15, 1643–1661, https://doi.org/10.5194/bg-15-1643-2018, https://doi.org/10.5194/bg-15-1643-2018, 2018
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We estimated monthly air–sea CO2 fluxes in the Arctic Ocean and its adjacent seas north of 60° N from 1997 to 2014, after mapping pCO2 in the surface water using a self-organizing map technique. The addition of Chl a as a parameter enabled us to improve the estimate of pCO2 via better representation of its decline in spring. The uncertainty in the CO2 flux estimate was reduced, and a net annual Arctic Ocean CO2 uptake of 180 ± 130 Tg C y−1 was determined to be significant.
Alizée Roobaert, Goulven G. Laruelle, Peter Landschützer, and Pierre Regnier
Biogeosciences, 15, 1701–1720, https://doi.org/10.5194/bg-15-1701-2018, https://doi.org/10.5194/bg-15-1701-2018, 2018
Chao Zhang, Huiwang Gao, Xiaohong Yao, Zongbo Shi, Jinhui Shi, Yang Yu, Ling Meng, and Xinyu Guo
Biogeosciences, 15, 749–765, https://doi.org/10.5194/bg-15-749-2018, https://doi.org/10.5194/bg-15-749-2018, 2018
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This study compares the response of phytoplankton growth in the northwest Pacific to those in the Yellow Sea. In general, larger positive responses of phytoplankton induced by combined nutrients (in the subtropical gyre of the northwest Pacific) than those induced by a single nutrient (in the Kuroshio Extension and the Yellow Sea) from the dust are observed. We also emphasize the importance of an increase in bioavailable P stock for phytoplankton growth following dust addition.
Goulven G. Laruelle, Peter Landschützer, Nicolas Gruber, Jean-Louis Tison, Bruno Delille, and Pierre Regnier
Biogeosciences, 14, 4545–4561, https://doi.org/10.5194/bg-14-4545-2017, https://doi.org/10.5194/bg-14-4545-2017, 2017
Melchor González-Dávila, J. Magdalena Santana Casiano, and Francisco Machín
Biogeosciences, 14, 3859–3871, https://doi.org/10.5194/bg-14-3859-2017, https://doi.org/10.5194/bg-14-3859-2017, 2017
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The Mauritanian–Cap Vert upwelling is shown to be sensitive to climate change forcing on upwelling processes, which strongly affects the CO2 surface distribution, ocean acidification rates, and air–sea CO2 exchange. We confirmed an upwelling intensification, an increase in the CO2 outgassing, and an important decrease in the pH of the surface waters. Upwelling areas are poorly studied and VOS lines are shown as one of the most significant contributors to our knowledge of the ocean's response.
Cited articles
Abril, G. and Borges, A. V.: Carbon dioxide and methane emissions from estuaries, in: Greenhouse gas emissions from natural environments and hydroelectric reservoirs: fluxes and processes, Environmental Science Series, edited by: Tremblay, A., Varfalvy, L., Roehm, C., and Garneau, M., Berlin, Heidelberg, New York, 187–207, 2004.
Abril, G., Etcheber, H., Borges, A. V., and Frankignoulle, M.: Excess atmospheric carbon dioxide transported by rivers into the Scheldt estuary, Cr. Acad. Sci. II A., 330, 761–768, 2000.
Abril, G., Commarieu, M. V., Sottolichio, A., Bretel, P., and Guérin, F.: Turbidity limits gas exchange in a large macrotidal estuary, Estuar. Coast. Shelf. S., 83, 342–348, 2009.
Allan, R. P. and Soden, B. J.: Atmospheric warming and the amplification of precipitation extremes, Science, 321, 1481–1484, 2008.
Bai, Y., Cai, W.-J., He, X., Zhai, W., Pan, D., Dai, M., and Yu, P.: A mechanistic semi-analytical method for remotely sensing sea surface pCO2 in river-dominated coastal oceans: A case study from the East China Sea, J. Geophys. Res.-Oceans., 120, 2331–2349, 2015.
Borges, A. V.: Do we have enough pieces of the jigsaw to integrate CO2 fluxes in the coastal ocean?, Estuaries, 28, 3–27, 2005.
Borges, A. V. and Frankignoulle, M.: Distribution of surface carbon dioxide and air-sea exchange in the upwelling system off the Galician coast, Global Biogeochem. Cy., 16, 13-1–13-13, https://doi.org/10.1029/2000GB001385, 2002.
Borges, A. V. and Abril, G.: Carbon dioxide and methane dynamics in estuaries, in: Treatise on estuarine and coastal science, edited by: Wolanski, E. and McLusky, D., Academic Press, Waltham, 119–161, 2011.
Borges, A. V., Delille, B., Schiettecatte, L.-S., Gazeau, F., Abril, G., and Frankignoulle, M.: Gas transfer velocities of CO2 in three European estuaries (Randers Fjord, Scheldt, and Thames), Limnol. Oceanogr., 49, 1630–1641, 2004.
Borges, A. V., Delille, B., and Frankignoulle, M.: Budgeting sinks and sources of CO2 in the coastal ocean: Diversity of ecosystems counts, Geophys. Res. Lett., 32, 1–4, 2005.
Borges, A. V., Schiettecatte, L.-S., Abril, G., Delille, B., and Gazeau, F.: Carbon dioxide in European coastal waters, Estuar. Coast. Shelf. S., 70, 375–387, 2006.
Cai, W.-J.: Estuarine and coastal ocean carbon paradox: CO2 sinks or sites of terrestrial carbon incineration?, Annu. Rev. Mar. Sci., 3, 123–145, 2011.
Cai, W.-J. and Wang, Y.: The chemistry, fluxes, and sources of carbon dioxide in the estuarine waters of the Satilla and Altamaha Rivers, Georgia, Limnol. Oceanogr., 43, 657–668, 1998.
Cai, W.-J., Wang, Y., and Hodson, R. E.: Acid-base properties of dissolved organic matter in the estuarine waters of Georgia, USA, Geochim. Cosmochim. Ac., 62, 473–483, 1998.
Cai, W.-J., Pomeroy, L., Moran, M. A., and Wang, Y.: Oxygen and carbon dioxide mass balance for the estuarine-intertidal marsh complex of five rivers in the southeastern US, Limnol. Oceanogr., 44, 639–649, 1999.
Cai, W.-J., Dai, M., and Wang, Y.: Air-sea exchange of carbon dioxide in ocean margins: A province-based synthesis, Geophys. Res. Lett., 33, 2–5, 2006.
Cai, W., Guo, X., Chen, A., Dai, M., Zhang, L., Zhai, W., Lohrenz, S. E., Yin, K., Harrison, P. J., and Wang, Y.: A comparative overview of weathering intensity and HCO3- flux in the world's major rivers with emphasis on the Changjiang, Huanghe, Zhujiang (Pearl) and Mississippi Rivers, Cont. Shelf. Res., 28, 1538–1549, https://doi.org/10.1016/j.csr.2007.10.014, 2008.
Cai, W.-J., Hu, X., Huang, W.-J., Jiang, L.-Q., Wang, Y., Peng, T.-H., and Zhang, X.: Alkalinity distribution in the western North Atlantic Ocean margins, J. Geophys. Res-Oceans., 115, 1–15, 2010a.
Cai, W.-J., Luther, G. W. III., Cornwell, J. C., and Giblin, A. E.: Carbon cycling and the coupling between proton and electron transfer reactions in aquatic sediments in Lake Champlain, Aquat. Geochem., 16, 421–446, 2010b.
Chen, C.-T. A. and Borges, A. V.: Reconciling opposing views on carbon cycling in the coastal ocean: Continental shelves as sinks and near-shore ecosystems as sources of atmospheric CO2, Deep-Sea. Res. Pt. II., 56, 578–590, 2009.
Chen, C.-T. A., Huang, T.-H., Chen, Y.-C., Bai, Y., He, X., and Kang, Y.: Air-sea exchanges of CO2 in the world's coastal seas, Biogeosciences, 10, 6509–6544, https://doi.org/10.5194/bg-10-6509-2013, 2013.
Cifuentes, L. A., Sharp, J. H., and Fogel, M. L.: Stable carbon and nitrogen isotope biogeochemistry in the Delaware Estuary, Limnol. Oceanogr., 33, 1102–1115, 1988.
Crosswell, J. R., Wetz, M. S., Hales, B., and Paerl, H. W.: Air-water CO2 fluxes in the microtidal Neuse River Estuary, North Carolina, J. Geophys. Res-Oceans., 117, 1–12, 2012.
Culberson, C. H.: Dissolved oxygen, inorganic carbon, and the acid–base system in the Delaware Estuary, in: Ecology and Restoration of the Delaware River Basin, Pennsylvania Academy of Science, University of Michigan, 58–76, 1988.
Culberson, C. H., Pennock, J. R., Lee, B. W., Biggs, R. B., Church, T. M., and Sharp, J. H.: Data from the YABLED cruises. September 1981- July 1984. Oceanographic data Report Number 4. Del. Sea. Grant. Program, University of Delaware, 170 pp., 1987.
Dai, T. and Wiegert, R.G.: Estimation of the primary productivity of Spartina alterniflora using a canopy model, Ecography, 19, 410–423, 1996.
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, 1987.
Dickson, A. G., Sabine, C. L., and Christian, J. R.: Guide to best practices for ocean CO2 measurements, PICES Special Publications, 3, 90–101, 2007.
Frankignoulle, M., Abril, G., Borges A.V., Bourge, I., Canon, C., Delille, B., Libert, E., and Théate, J. M.: Carbon dioxide emission from European estuaries, Science, 282, 434–436, 1998.
Gran, G.: Determination of the equivalence point in potentiometric titrations Part II, Analyst, 77, 661–671, 1952.
Huang, W.-J., Wang, Y., and Cai, W.-J.: Assessment of sample storage techniques for total alkalinity and dissolved inorganic carbon in seawater, Limnol. Oceanogr.-Meth., 10, 711–717, 2012.
Huang, W.-J., Cai, W.-J., Wang, Y., Lohrenz, S. E., and Murrell, M. C.: The carbon dioxide system on the Mississippi River-dominated continental shelf in the northern Gulf of Mexico: 1. Distribution and air-sea CO2 flux, J. Geophys. Res-Oceans., 120, 1429–1445, 2015.
Hunt, C. W., Salisbury, J. C., Vandemark, D., and McGillis, W.: Contrasting Carbon Dioxide Inputs and Exchange in Three Adjacent New England Estuaries, Estuar. Coast, 34, 68–77, 2010.
Hunt, C. W., Salisbury, J. E., and Vandemark, D.: CO2 input dynamics and air–sea exchange in a large New England estuary, Estuar. Coast, 37, 1078–1091, 2014.
Jiang, L.-Q., Cai, W.-J., and Wang, Y.: A comparative study of carbon dioxide degassing in river- and marine-dominated estuaries, Limnol. Oceanogr., 53, 2603–2615, 2008a.
Jiang, L.-Q., Cai, W.-J., Wanninkhof, R., Wang, Y., and Lüger, H.: Air-sea CO2 fluxes on the US South Atlantic Bight: spatial and seasonal variability, J. Geophys. Res., 113, C07019, https://doi.org/10.1029/2007JC004366, 2008b.
Ketchum, B. H.: The distribution of salinity in the estuary of the Delaware River, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, 1952.
Laruelle, G. G., Lauerwald, R., Rotschi, J., Raymond, P. A., Hartmann, J., and Regnier, P.: Seasonal response of air-water CO2 exchange along the land-ocean aquatic continuum of the northeast North American coast, Biogeosciences, 12, 1447–1458, https://doi.org/10.5194/bg-12-1447-2015, 2015.
Lebo, M. L., Cifuentes, L. A., Fogel, M. L., Hoch, M. P., Keil, R. G., Kirchman, D. L., Ludlam, J. M., Pennock, J. R., Sharp, J. H., Spicer, P. T., and Velinsky, D. J.: Data from the Delaware Estuary Scenic Cruises, April 1986–September 1988, Oceanographic Data Report Number 7, Del. Sea. Grant. Program, University of Delaware, 139 pp., 1990.
Mehrbach, 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, 1973.
Millero, F. J., Graham, T. B., Huang, F., Bustos-Serrano, H., and Pierrot, D.: Dissociation constants of carbonic acid in seawater as a function of salinity and temperature, Mar. Chem., 100, 80–94, 2006.
McGillis, W. R., Edson, J. B., Hare, J. E., and Fairall, C. W.: Direct covariance air-sea CO2 fluxes, J. Geophys. Res-Oceans., 106, 16729–16745, 2001.
McGillis, W. R., Edson, J. B., Zappa, C. J., Ware, J. D., McKenna, S. P., Terray, E. A., Hare, J. E., Fairall, C. W., Drennan, W., Donelan, M., DeGrandpre, M. D., Wanninkhof, R., and Feely, R. A.: Air-sea CO2 exchange in the equatorial Pacific, J. Geophys. Res-Oceans., 109, 1978–2012, 2004.
Neubauer, S. and Anderson, I. C.: Transport of dissolved inorganic carbon from a tidal freshwater marsh to the York River estuary, Limnol. Oceanogr., 48, 299–307, 2003.
Pennock, J. R. and Sharp, J. H.: Temporal alternation between light and nutrient-limitation of phytoplankton production in a coastal plain estuary, Mar. Ecol.-Prog. Ser., 111, 275–288, 1994.
Pierrot, D., Lewis, E., and Wallace, D. W. R.: CO2SYS DOS Program Developed for CO2System Calculations. ORNL/CDIAC-105, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, California, 2006.
Raymond, P. A. and Cole, J. J.: Gas exchange in rivers and estuaries: choosing a gas transfer velocity, Estuaries, 24, 312–317, 2001.
Raymond, P. A., Caraco, N. F., and Cole, J. J.: Carbon dioxide concentration and atmospheric flux in the Hudson River, Estuaries, 20, 381–390, 1997.
Raymond, P. A., Bauer, J. E., and Cole, J. J.: Atmospheric CO2 evasion, dissolved inorganic carbon production, and net heterotrophy in the York River estuary, Limnol. Oceanogr., 45, 1707–1717, 2000.
Regnier, P., Friedlingstein, P., Ciais, P., Mackenzie, F. T., Gruber, N., Janssens, I. A., Laruelle, G. G., Lauerwald, R., Luyssaert, S., Andersson, A. J., Arndt, S., Arnosti, C., Borges, A. V., Dale, A. W., Gallego-Sala, A., Godderis, Y., Goossens, N., Hartmann, J., Heinze, C., Ilyina, T., Joos, F., LaRowe, D. E., Leifeld, J., Meysman, F. J. R., Munhoven, G., Raymond, P. A., Spahni, R., Suntharalingam, P., and Thullner, M.: Anthropogenic perturbation of the carbon fluxes from land to ocean, Nat. Geosci., 6, 597–607, https://doi.org/10.1038/ngeo1830, 2013.
Salisbury, J. E., Vandemark, D., Hunt, C. W., Campbell, J. W., McGillis, W. R., and McDowell, W. H.: Seasonal observations of surface waters in two Gulf of Maine estuary-plume systems: Relationships between watershed attributes, optical measurements and surface pCO2, Estuar. Coast. Shelf. S., 77, 245–252, 2008.
Sharp, J. H.: The Delaware Estuary: Research as background for estuarine management and development, Univ. Delaware Sea Grant College Program, 79–118, 1983.
Sharp, J. H.: Estuarine oxygen dynamics: What can we learn about hypoxia from long-time records in the Delaware Estuary?, Limnol. Oceanogr., 55, 535–548, 2010.
Sharp, J. H., Yoshiyama, K., Parker, A. E., Schwartz, M. C., Curless, S. E., Beauregard, A. Y., Ossolinski, J. E., and Davis, A. R.: A biogeochemical view of estuarine eutrophication: seasonal and spatial trends and correlations in the Delaware Estuary, Estuar. Coast, 32, 1023–1043, 2009.
Sheldon, J. E. and Merryl, A.: A comparison of residence time calculations using simple compartment models of the Altamaha River Estuary, Georgia, Estuaries, 25, 1304–1317, 2002.
Takahashi, T., Ólafsson, J., Goddard, J. G., Chipman, D. W., and Sutherland, S. C.: Seasonal variation of CO2 and nutrient salts over the high latitude oceans: A comparative study, Global Biogeochem. Cy., 7, 843–878, 1993.
Takahashi, T., Sutherland, S. C., Sweeney, C., Poisson, A., Metzl, N., Tilbrook, T., Bates, N., Wanninkhof, R., Feely, R. A., Sabine, C., Olafsson, J., and Nojiri, Y.: Global sea-air CO2 flux based on climatological surface ocean pCO2, and seasonal biological and temperature effects, Deep-Sea Res. Pt. II, 49, 1601–1622, 2002.
Trabalka, J. R. and Reichle, D. E.: The changing carbon cycle: A global analysis, Springer, New York, 2013.
Voynova, Y. G. and Sharp, J. H.: Anomalous biogeochemical response to a flooding event in the Delaware Estuary: a possible typology shift due to climate change, Estuar. Coast, 35, 943–958, 2012.
Wang, Z. A. and Cai, W.-J.: Carbon dioxide degassing and inorganic carbon export from a marsh-dominated estuary (the Duplin River): A marsh CO2 pump, Limnol. Oceanogr., 49, 341–354, 2004.
Wanninkhof, R.: Relationship between wind speed and gas exchange over the ocean, J. Geophys. Res-Ocean., 97, 7373–7382, https://doi.org/10.1029/92jc00188, 1992.
Wanninkhof, R.: Relationship between wind speed and gas exchange over the ocean revisited, Limnol. Oceanogr-Meth., 12, 351–362, 2014.
Wanninkhof, R., Doney, S. C., Takahashi, T., and McGillis, W. R.: The effect of using time-averaged winds on regional air-sea CO2 fluxes, in: Gas transfer at water surfaces. Geophysical Monograph Series, edited by: Donelan, M., Drennan, W., Saltzman, E., and Wanninkhor, R., AGU, Washington D.C., 351–357, 2002.
Wanninkhof, R., Asher, W. E., Ho, D. T., Sweeney, C., and McGillis, W. R.: Advances in quantifying air-sea gas exchange and environmental forcing, Ann. Rev. Mar. Sci., 1, 213–244, 2009.
Weiss, R. F.: Carbon dioxide in water and seawater: the solubility of non-ideal gas, Mar. Chem., 2, 221–231, 1974.
Yoshiyama, K. and Sharp, H. J.: Phytoplankton response to nutrient enrichment in an urbanized estuary: Apparent inhibition of primary production by overeutrophication, Limnol. Oceanogr., 51, 424–434, 2006.
Zappa, C. J., McGillis, W. R., Raymond, P, A., Edson, J. B., Hintsa, E. J., Zemmelink, H. J., Dacey, J. W. H., and Ho, D. T.: Environmental turbulent mixing controls on air-water gas exchange in marine and aquatic systems, Geophys. Res. Lett., 34, L10601, https://doi.org/10.1029/2006GL028790, 2007.
Short summary
In this paper, we report the first seasonal distribution of pCO2 and air–water CO2 flux in the Delaware Estuary. We further assess the temperature and biological effects on pCO2 distributions as well as the overall contribution of internal versus riverine sources on CO2 inputs to the estuarine system. Finally, we present a summarized pCO2 distribution over the study area and provide a conceptual model to illustrate the control mechanisms on surface water CO2 dynamics in the Delaware Estuary.
In this paper, we report the first seasonal distribution of pCO2 and air–water CO2 flux in...
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