Articles | Volume 17, issue 1
Research article 18 Jan 2021
Research article | 18 Jan 2021
Circulation timescales of Atlantic Water in the Arctic Ocean determined from anthropogenic radionuclides
Anne-Marie Wefing et al.
No articles found.
Amanda R. Fay, Luke Gregor, Peter Landschützer, Galen A. McKinley, Nicolas Gruber, Marion Gehlen, Yosuke Iida, Goulven G. Laruelle, Christian Rödenbeck, and Jiye Zeng
Earth Syst. Sci. Data Discuss.,
Preprint under review for ESSDShort summary
The movement of carbon dioxide from the atmosphere to the ocean is estimated using surface ocean carbon (pCO2) measurements and an equation including variables such as temperature and wind speed; the choices of these variables lead to uncertainties. Introducing the SeaFlux ensemble which provides carbon flux maps calculated in a consistent manner, thus reducing uncertainty by using common choices for wind speed and a set definition of "global" coverage.
Luke Gregor and Nicolas Gruber
Earth Syst. Sci. Data, 13, 777–808,Short summary
Ocean acidification (OA) has altered the ocean's carbonate chemistry, with consequences for marine life. Yet, no observation-based data set exists that permits us to study changes in OA. We fill this gap with a global data set of relevant surface ocean parameters over the period 1985–2018. This data set, OceanSODA-ETHZ, was created by using satellite and other data to extrapolate ship-based measurements of carbon dioxide and total alkalinity from which parameters for OA were computed.
Derara Hailegeorgis, Zouhair Lachkar, Christoph Rieper, and Nicolas Gruber
Biogeosciences, 18, 303–325,Short summary
Using a Lagrangian modeling approach, this study provides a quantitative analysis of water and nitrogen offshore transport in the Canary Current System. We investigate the timescales, reach and structure of offshore transport and demonstrate that the Canary upwelling is a key source of nutrients to the open North Atlantic Ocean. Our findings stress the need for improving the representation of the Canary system and other eastern boundary upwelling systems in global coarse-resolution models.
Giulia Bonino, Elisa Lovecchio, Nicolas Gruber, Matthias Münnich, Simona Masina, and Doroteaciro Iovino
Revised manuscript accepted for BGShort summary
Seasonal variations of processes such as upwelling and biological production that happen along the north-western African coast can modulate the temporal variability of the biological activity of the adjacent open North Atlantic hundreds of kilometers away from the coast thanks to the lateral transport of the coastal organic carbon. This happens with a temporal delay, which is smaller than a season up to roughly 500 km from the coast due to the intense transport by small scale filaments.
Leonie Peti, Kathryn E. Fitzsimmons, Jenni L. Hopkins, Andreas Nilsson, Toshiyuki Fujioka, David Fink, Charles Mifsud, Marcus Christl, Raimund Muscheler, and Paul C. Augustinus
Geochronology, 2, 367–410,Short summary
Orakei Basin – a former maar lake in Auckland, New Zealand – provides an outstanding sediment record over the last ca. 130 000 years, but an age model is required to allow the reconstruction of climate change and volcanic eruptions contained in the sequence. To construct a relationship between depth in the sediment core and age of deposition, we combined tephrochronology, radiocarbon dating, luminescence dating, and the relative intensity of the paleomagnetic field in a Bayesian age–depth model.
Pierre Friedlingstein, Michael O'Sullivan, Matthew W. Jones, Robbie M. Andrew, Judith Hauck, Are Olsen, Glen P. Peters, Wouter Peters, Julia Pongratz, Stephen Sitch, Corinne Le Quéré, Josep G. Canadell, Philippe Ciais, Robert B. Jackson, Simone Alin, Luiz E. O. C. Aragão, Almut Arneth, Vivek Arora, Nicholas R. Bates, Meike Becker, Alice Benoit-Cattin, Henry C. Bittig, Laurent Bopp, Selma Bultan, Naveen Chandra, Frédéric Chevallier, Louise P. Chini, Wiley Evans, Liesbeth Florentie, Piers M. Forster, Thomas Gasser, Marion Gehlen, Dennis Gilfillan, Thanos Gkritzalis, Luke Gregor, Nicolas Gruber, Ian Harris, Kerstin Hartung, Vanessa Haverd, Richard A. Houghton, Tatiana Ilyina, Atul K. Jain, Emilie Joetzjer, Koji Kadono, Etsushi Kato, Vassilis Kitidis, Jan Ivar Korsbakken, Peter Landschützer, Nathalie Lefèvre, Andrew Lenton, Sebastian Lienert, Zhu Liu, Danica Lombardozzi, Gregg Marland, Nicolas Metzl, David R. Munro, Julia E. M. S. Nabel, Shin-Ichiro Nakaoka, Yosuke Niwa, Kevin O'Brien, Tsuneo Ono, Paul I. Palmer, Denis Pierrot, Benjamin Poulter, Laure Resplandy, Eddy Robertson, Christian Rödenbeck, Jörg Schwinger, Roland Séférian, Ingunn Skjelvan, Adam J. P. Smith, Adrienne J. Sutton, Toste Tanhua, Pieter P. Tans, Hanqin Tian, Bronte Tilbrook, Guido van der Werf, Nicolas Vuichard, Anthony P. Walker, Rik Wanninkhof, Andrew J. Watson, David Willis, Andrew J. Wiltshire, Wenping Yuan, Xu Yue, and Sönke Zaehle
Earth Syst. Sci. Data, 12, 3269–3340,Short summary
The Global Carbon Budget 2020 describes the data sets and methodology used to quantify the emissions of carbon dioxide and their partitioning among the atmosphere, land, and ocean. These living data are updated every year to provide the highest transparency and traceability in the reporting of CO2, the key driver of climate change.
Tessa Sophia van der Voort, Thomas M. Blattmann, Muhammed Usman, Daniel Montluçon, Thomas Loeffler, Maria Luisa Tavagna, Nicolas Gruber, and Timothy Ian Eglinton
Earth Syst. Sci. Data Discuss.,
Revised manuscript accepted for ESSDShort summary
Ocean sediments form the largest and most long-term storage or organic carbon. Despite their global importance, information on these sediments is often scattered, incomplete or inaccessible. Here we present MOSAIC (Modern Ocean Sediment Archive and Inventory of Carbon, mosaic.ethz.ch), a (radio)carbon-centric database that addresses this information gap. This database provides a platform for assessing the transport, deposition and storage of carbon in ocean surface sediments.
Marius L. Huber, Maarten Lupker, Sean F. Gallen, Marcus Christl, and Ananta P. Gajurel
Earth Surf. Dynam., 8, 769–787,Short summary
Large boulders found in two Himalayan valleys show signs of long fluvial transport (>10 km). Paleo-discharges required to mobilize these boulders exceed typical monsoon discharges. Exposure dating shows that a cluster of these boulders was emplaced ca. 5 kyr ago. This period is coeval with a weakening of the Indian monsoon and glacier retreat in the area. We, therefore, suggest that glacier lake outburst floods are likely mechanisms that can explain these exceptional transport processes.
David Mair, Alessandro Lechmann, Romain Delunel, Serdar Yeşilyurt, Dmitry Tikhomirov, Christof Vockenhuber, Marcus Christl, Naki Akçar, and Fritz Schlunegger
Earth Surf. Dynam., 8, 637–659,
Damiano Righetti, Meike Vogt, Niklaus E. Zimmermann, Michael D. Guiry, and Nicolas Gruber
Earth Syst. Sci. Data, 12, 907–933,Short summary
Phytoplankton sustain marine life, as they are the principal primary producers in the global ocean. Despite their ecological importance, their distribution and diversity patterns are poorly known, mostly due to data limitations. We present a global dataset that synthesizes over 1.3 million occurrences of phytoplankton from public archives. It is easily extendable. This dataset can be used to characterize phytoplankton distribution and diversity in current and future oceans.
Ole Valk, Michiel M. Rutgers van der Loeff, Walter Geibert, Sandra Gdaniec, S. Bradley Moran, Kate Lepore, Robert Lawrence Edwards, Yanbin Lu, Viena Puigcorbé, Nuria Casacuberta, Ronja Paffrath, William Smethie, and Matthieu Roy-Barman
Ocean Sci., 16, 221–234,Short summary
After 2007 230Th decreased significantly in the central Amundsen Basin. This decrease is accompanied by a circulation change, indicated by changes in salinity. Ventilation of waters is most likely not the reason for the observed depletion in 230Th as atmospherically derived tracers do not reveal an increase in ventilation rate. It is suggested that these interior waters have undergone enhanced scavenging of Th during transit from Fram Strait and the Barents Sea to the central Amundsen Basin.
Pierre Friedlingstein, Matthew W. Jones, Michael O'Sullivan, Robbie M. Andrew, Judith Hauck, Glen P. Peters, Wouter Peters, Julia Pongratz, Stephen Sitch, Corinne Le Quéré, Dorothee C. E. Bakker, Josep G. Canadell, Philippe Ciais, Robert B. Jackson, Peter Anthoni, Leticia Barbero, Ana Bastos, Vladislav Bastrikov, Meike Becker, Laurent Bopp, Erik Buitenhuis, Naveen Chandra, Frédéric Chevallier, Louise P. Chini, Kim I. Currie, Richard A. Feely, Marion Gehlen, Dennis Gilfillan, Thanos Gkritzalis, Daniel S. Goll, Nicolas Gruber, Sören Gutekunst, Ian Harris, Vanessa Haverd, Richard A. Houghton, George Hurtt, Tatiana Ilyina, Atul K. Jain, Emilie Joetzjer, Jed O. Kaplan, Etsushi Kato, Kees Klein Goldewijk, Jan Ivar Korsbakken, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Andrew Lenton, Sebastian Lienert, Danica Lombardozzi, Gregg Marland, Patrick C. McGuire, Joe R. Melton, Nicolas Metzl, David R. Munro, Julia E. M. S. Nabel, Shin-Ichiro Nakaoka, Craig Neill, Abdirahman M. Omar, Tsuneo Ono, Anna Peregon, Denis Pierrot, Benjamin Poulter, Gregor Rehder, Laure Resplandy, Eddy Robertson, Christian Rödenbeck, Roland Séférian, Jörg Schwinger, Naomi Smith, Pieter P. Tans, Hanqin Tian, Bronte Tilbrook, Francesco N. Tubiello, Guido R. van der Werf, Andrew J. Wiltshire, and Sönke Zaehle
Earth Syst. Sci. Data, 11, 1783–1838,Short summary
The Global Carbon Budget 2019 describes the data sets and methodology used to quantify the emissions of carbon dioxide and their partitioning among the atmosphere, land, and ocean. These living data are updated every year to provide the highest transparency and traceability in the reporting of CO2, the key driver of climate change.
François Clapuyt, Veerle Vanacker, Marcus Christl, Kristof Van Oost, and Fritz Schlunegger
Solid Earth, 10, 1489–1503,Short summary
Using state-of-the-art geomorphic techniques, we quantified a 2-order of magnitude discrepancy between annual, decadal, and millennial sediment fluxes of a landslide-affected mountainous river catchment in the Swiss Alps. Our results illustrate that the impact of a single sediment pulse is strongly attenuated at larger spatial and temporal scales by sediment transport. The accumulation of multiple sediment pulses has rather a measurable impact on the regional pattern of sediment fluxes.
Riley X. Brady, Nicole S. Lovenduski, Michael A. Alexander, Michael Jacox, and Nicolas Gruber
Biogeosciences, 16, 329–346,
Géraldine Sarthou, Pascale Lherminier, Eric P. Achterberg, Fernando Alonso-Pérez, Eva Bucciarelli, Julia Boutorh, Vincent Bouvier, Edward A. Boyle, Pierre Branellec, Lidia I. Carracedo, Nuria Casacuberta, Maxi Castrillejo, Marie Cheize, Leonardo Contreira Pereira, Daniel Cossa, Nathalie Daniault, Emmanuel De Saint-Léger, Frank Dehairs, Feifei Deng, Floriane Desprez de Gésincourt, Jérémy Devesa, Lorna Foliot, Debany Fonseca-Batista, Morgane Gallinari, Maribel I. García-Ibáñez, Arthur Gourain, Emilie Grossteffan, Michel Hamon, Lars Eric Heimbürger, Gideon M. Henderson, Catherine Jeandel, Catherine Kermabon, François Lacan, Philippe Le Bot, Manon Le Goff, Emilie Le Roy, Alison Lefèbvre, Stéphane Leizour, Nolwenn Lemaitre, Pere Masqué, Olivier Ménage, Jan-Lukas Menzel Barraqueta, Herlé Mercier, Fabien Perault, Fiz F. Pérez, Hélène F. Planquette, Frédéric Planchon, Arnout Roukaerts, Virginie Sanial, Raphaëlle Sauzède, Catherine Schmechtig, Rachel U. Shelley, Gillian Stewart, Jill N. Sutton, Yi Tang, Nadine Tisnérat-Laborde, Manon Tonnard, Paul Tréguer, Pieter van Beek, Cheryl M. Zurbrick, and Patricia Zunino
Biogeosciences, 15, 7097–7109,Short summary
The GEOVIDE cruise (GEOTRACES Section GA01) was conducted in the North Atlantic Ocean and Labrador Sea in May–June 2014. In this special issue, results from GEOVIDE, including physical oceanography and trace element and isotope cyclings, are presented among 17 articles. Here, the scientific context, project objectives, and scientific strategy of GEOVIDE are provided, along with an overview of the main results from the articles published in the special issue.
Cara Nissen, Meike Vogt, Matthias Münnich, Nicolas Gruber, and F. Alexander Haumann
Biogeosciences, 15, 6997–7024,Short summary
Using a regional ocean model, we find that coccolithophore biomass in the Southern Ocean is highest in the subantarctic in late summer when diatom growth becomes limited by silicate. We show that zooplankton grazing is crucial to explain phytoplankton biomass distributions in this area and conclude that assessments of future distributions should not only consider physical and chemical factors (temperature, light, nutrients, pH), but also interactions with other phytoplankton or zooplankton.
Maxi Castrillejo, Núria Casacuberta, Marcus Christl, Christof Vockenhuber, Hans-Arno Synal, Maribel I. García-Ibáñez, Pascale Lherminier, Géraldine Sarthou, Jordi Garcia-Orellana, and Pere Masqué
Biogeosciences, 15, 5545–5564,Short summary
The investigation of water mass transport pathways and timescales is important to understand the global ocean circulation. Following earlier studies, we use artificial radionuclides introduced to the oceans in the 1950s to investigate the water transport in the subpolar North Atlantic (SPNA). For the first time, we combine measurements of the long-lived iodine-129 and uranium-236 to confirm earlier findings/hypotheses and to better understand shallow and deep ventilation processes in the SPNA.
Max Boxleitner, Susan Ivy-Ochs, Dagmar Brandova, Marcus Christl, Markus Egli, and Max Maisch
Geogr. Helv., 73, 241–252,
Elisa Lovecchio, Nicolas Gruber, and Matthias Münnich
Biogeosciences, 15, 5061–5091,Short summary
We find that the ocean's flow on scales of a few tens to a few hundred km has a central role in the lateral redistribution of the organic carbon from the coast to the open ocean. Narrow coastal filaments drive the offshore flux of organic carbon and strongly enhance its availability up to 1000 km from the coast. Eddies extend the flux up to 2000 km offshore containing 30 % of the organic matter in the open waters. Resolving these scales is essential to capture the coastal/open ocean coupling.
Ivy Frenger, Matthias Münnich, and Nicolas Gruber
Biogeosciences, 15, 4781–4798,Short summary
Although mesoscale ocean eddies are ubiquitous in the Southern Ocean (SO), their regional and seasonal association with phytoplankton has not been quantified. We identify over 100 000 eddies and determine the associated phytoplankton biomass anomalies using satellite-based chlorophyll (Chl) as a proxy. The emerging Chl anomalies can be explained largely by lateral advection of Chl by eddies. This impact of eddies on phytoplankton may implicate downstream effects on SO biogeochemical properties.
Catharina Dieleman, Susan Ivy-Ochs, Kristina Hippe, Olivia Kronig, Florian Kober, and Marcus Christl
E&G Quaternary Sci. J., 67, 17–23,
Antoine Cogez, Frédéric Herman, Éric Pelt, Thierry Reuschlé, Gilles Morvan, Christopher M. Darvill, Kevin P. Norton, Marcus Christl, Lena Märki, and François Chabaux
Earth Surf. Dynam., 6, 121–140,Short summary
Sediments produced by glaciers are transported by rivers and wind toward the ocean. During their journey, these sediments are weathered, and we know that this has an impact on climate. One key factor is time, but the duration of this journey is largely unknown. We were able to measure the average time that sediment spends only in the glacial area. This time is 100–200 kyr, which is long and allows a lot of processes to act on sediments during their journey.
Lorenz Wüthrich, Claudio Brändli, Régis Braucher, Heinz Veit, Negar Haghipour, Carla Terrizzano, Marcus Christl, Christian Gnägi, and Roland Zech
E&G Quaternary Sci. J., 66, 57–68,
Yu Liu, Nicolas Gruber, and Dominik Brunner
Atmos. Chem. Phys., 17, 14145–14169,Short summary
We analyze fossil fuel signals in atmospheric CO2 over Europe using a high-resolution atmospheric transport model and diurnal emission data. We find that fossil fuel CO2 accounts for more than half of the atmospheric CO2 variations, mainly at diurnal timescales. The covariance of diurnal emission and transport also leads to a substantial rectification effect. Thus, the consideration of diurnal emissions and high-resolution transport is paramount for accurately modeling the fossil fuel signal.
Goulven G. Laruelle, Peter Landschützer, Nicolas Gruber, Jean-Louis Tison, Bruno Delille, and Pierre Regnier
Biogeosciences, 14, 4545–4561,
Maarten Lupker, Jérôme Lavé, Christian France-Lanord, Marcus Christl, Didier Bourlès, Julien Carcaillet, Colin Maden, Rainer Wieler, Mustafizur Rahman, Devojit Bezbaruah, and Liu Xiaohan
Earth Surf. Dynam., 5, 429–449,Short summary
We use geochemical approaches (10Be) on river sediments to quantify the erosion rates across the Tsangpo-Brahmaputra (TB) catchment in the eastern Himalayas. Our approach confirms the high erosion rates in the eastern Himalayan syntaxis region and we suggest that the abrasion of landslide material in the syntaxis is a key process in explaining how erosion signals are transferred to the sediment load.
Jakob Zscheischler, Miguel D. Mahecha, Valerio Avitabile, Leonardo Calle, Nuno Carvalhais, Philippe Ciais, Fabian Gans, Nicolas Gruber, Jens Hartmann, Martin Herold, Kazuhito Ichii, Martin Jung, Peter Landschützer, Goulven G. Laruelle, Ronny Lauerwald, Dario Papale, Philippe Peylin, Benjamin Poulter, Deepak Ray, Pierre Regnier, Christian Rödenbeck, Rosa M. Roman-Cuesta, Christopher Schwalm, Gianluca Tramontana, Alexandra Tyukavina, Riccardo Valentini, Guido van der Werf, Tristram O. West, Julie E. Wolf, and Markus Reichstein
Biogeosciences, 14, 3685–3703,Short summary
Here we synthesize a wide range of global spatiotemporal observational data on carbon exchanges between the Earth surface and the atmosphere. A key challenge was to consistently combining observational products of terrestrial and aquatic surfaces. Our primary goal is to identify today’s key uncertainties and observational shortcomings that would need to be addressed in future measurement campaigns or expansions of in situ observatories.
Elisa Lovecchio, Nicolas Gruber, Matthias Münnich, and Zouhair Lachkar
Biogeosciences, 14, 3337–3369,Short summary
We find that a big portion of the phytoplankton, zooplankton, and detrital organic matter produced near the northern African coast is laterally transported towards the open North Atlantic. This offshore flux sustains a relevant part of the biological activity in the open sea and reaches as far as the middle of the North Atlantic. Our results, obtained with a state-of-the-art model, highlight the fundamental role of the narrow but productive coastal ocean in sustaining global marine life.
Eric Laloy, Koen Beerten, Veerle Vanacker, Marcus Christl, Bart Rogiers, and Laurent Wouters
Earth Surf. Dynam., 5, 331–345,Short summary
Over very long timescales, 100 000 years or more, landscapes may drastically change. Sediments preserved in these landscapes have a cosmogenic radionuclide inventory that tell us when and how fast such changes took place. In this paper, we provide first evidence of an elevated long-term erosion rate of the northwestern Campine Plateau (lowland Europe), which can be explained by the loose nature of the subsoil.
Jean L. Dixon, Friedhelm von Blanckenburg, Kurt Stüwe, and Marcus Christl
Earth Surf. Dynam., 4, 895–909,Short summary
We quantify the glacial legacy of Holocene erosion at the eastern edge of the European Alps and add insight to the debate on drivers of Alpine erosion. We present the first data explicitly comparing 10Be-based erosion rates in previously glaciated and non-glaciated basins (n = 26). Erosion rates vary 5-fold across the region, correlating with local topography and glacial history. Our approach and unique study site allow us to isolate the role of glacial topographic legacies from other controls.
Charlotte Laufkötter, Meike Vogt, Nicolas Gruber, Olivier Aumont, Laurent Bopp, Scott C. Doney, John P. Dunne, Judith Hauck, Jasmin G. John, Ivan D. Lima, Roland Seferian, and Christoph Völker
Biogeosciences, 13, 4023–4047,Short summary
We compare future projections in marine export production, generated by four ecosystem models under IPCC's high-emission scenario RCP8.5. While all models project decreases in export, they differ strongly regarding the drivers. The formation of sinking particles of organic matter is the most uncertain process with models not agreeing on either magnitude or the direction of change. Changes in diatom concentration are a strong driver for export in some models but of low significance in others.
C. Rödenbeck, D. C. E. Bakker, N. Gruber, Y. Iida, A. R. Jacobson, S. Jones, P. Landschützer, N. Metzl, S. Nakaoka, A. Olsen, G.-H. Park, P. Peylin, K. B. Rodgers, T. P. Sasse, U. Schuster, J. D. Shutler, V. Valsala, R. Wanninkhof, and J. Zeng
Biogeosciences, 12, 7251–7278,Short summary
This study investigates variations in the CO2 uptake of the ocean from year to year. These variations have been calculated from measurements of the surface-ocean carbon content by various different interpolation methods. The equatorial Pacific is estimated to be the region with the strongest year-to-year variations, tied to the El Nino phase. The global ocean CO2 uptake gradually increased from about the year 2000. The comparison of the interpolation methods identifies these findings as robust.
C. Laufkötter, M. Vogt, N. Gruber, M. Aita-Noguchi, O. Aumont, L. Bopp, E. Buitenhuis, S. C. Doney, J. Dunne, T. Hashioka, J. Hauck, T. Hirata, J. John, C. Le Quéré, I. D. Lima, H. Nakano, R. Seferian, I. Totterdell, M. Vichi, and C. Völker
Biogeosciences, 12, 6955–6984,Short summary
We analyze changes in marine net primary production (NPP) and its drivers for the 21st century in 9 marine ecosystem models under the RCP8.5 scenario. NPP decreases in 5 models and increases in 1 model; 3 models show no significant trend. The main drivers include stronger nutrient limitation, but in many models warming-induced increases in phytoplankton growth outbalance the nutrient effect. Temperature-driven increases in grazing and other loss processes cause a net decrease in biomass and NPP.
R. Arruda, P. H. R. Calil, A. A. Bianchi, S. C. Doney, N. Gruber, I. Lima, and G. Turi
Biogeosciences, 12, 5793–5809,Short summary
We investigate surface ocean pCO2 and air-sea CO2 fluxes climatological variability through biogeochemical modeling in the southwestern Atlantic Ocean. Surface ocean pCO2 spatio-temporal variability was found to be controlled mainly by temperature and Dissolved Inorganic Carbon (DIC). Biological production, physical transport and solubility are the main controlling processes. With different behaviors on subtropical and subantarctic open ocean, and on inner/outer continental shelves.
B. Oney, S. Henne, N. Gruber, M. Leuenberger, I. Bamberger, W. Eugster, and D. Brunner
Atmos. Chem. Phys., 15, 11147–11164,Short summary
We present a detailed analysis of a new greenhouse gas measurement network in the Swiss Plateau, situated between the Jura mountains and the Alps. We find the network's measurements to be information rich and suitable for studying surface carbon fluxes of the study region. However, we are limited by the high-resolution (2km) atmospheric transport model's ability to simulate meteorology at the individual measurement stations, especially at those situated in rough terrain.
A. Jahn, K. Lindsay, X. Giraud, N. Gruber, B. L. Otto-Bliesner, Z. Liu, and E. C. Brady
Geosci. Model Dev., 8, 2419–2434,Short summary
Carbon isotopes have been added to the ocean model of the Community Earth System Model version 1 (CESM1). This paper describes the details of how the abiotic 14C tracer and the biotic 13C and 14C tracers were added to the existing ocean model of the CESM. In addition, it shows the first results of the new model features compared to observational data for the 1990s.
J. Martinez-Rey, L. Bopp, M. Gehlen, A. Tagliabue, and N. Gruber
Biogeosciences, 12, 4133–4148,
S. K. Lauvset, N. Gruber, P. Landschützer, A. Olsen, and J. Tjiputra
Biogeosciences, 12, 1285–1298,Short summary
This paper utilizes the SOCATv2 data product to calculate surface ocean pH. The pH data are divided into 17 biomes, and a linear regression is used to derive the long-term trend of pH in each biome. The results are consistent with the trends observed at time series stations. The uncertainties are too large for a mechanistic understanding of the driving forces behind the trend, but there are indications that concurrent changes in chemistry create spatial variability.
S. Sitch, P. Friedlingstein, N. Gruber, S. D. Jones, G. Murray-Tortarolo, A. Ahlström, S. C. Doney, H. Graven, C. Heinze, C. Huntingford, S. Levis, P. E. Levy, M. Lomas, B. Poulter, N. Viovy, S. Zaehle, N. Zeng, A. Arneth, G. Bonan, L. Bopp, J. G. Canadell, F. Chevallier, P. Ciais, R. Ellis, M. Gloor, P. Peylin, S. L. Piao, C. Le Quéré, B. Smith, Z. Zhu, and R. Myneni
Biogeosciences, 12, 653–679,
F. Fendereski, M. Vogt, M. R. Payne, Z. Lachkar, N. Gruber, A. Salmanmahiny, and S. A. Hosseini
Biogeosciences, 11, 6451–6470,
P. Ciais, A. J. Dolman, A. Bombelli, R. Duren, A. Peregon, P. J. Rayner, C. Miller, N. Gobron, G. Kinderman, G. Marland, N. Gruber, F. Chevallier, R. J. Andres, G. Balsamo, L. Bopp, F.-M. Bréon, G. Broquet, R. Dargaville, T. J. Battin, A. Borges, H. Bovensmann, M. Buchwitz, J. Butler, J. G. Canadell, R. B. Cook, R. DeFries, R. Engelen, K. R. Gurney, C. Heinze, M. Heimann, A. Held, M. Henry, B. Law, S. Luyssaert, J. Miller, T. Moriyama, C. Moulin, R. B. Myneni, C. Nussli, M. Obersteiner, D. Ojima, Y. Pan, J.-D. Paris, S. L. Piao, B. Poulter, S. Plummer, S. Quegan, P. Raymond, M. Reichstein, L. Rivier, C. Sabine, D. Schimel, O. Tarasova, R. Valentini, R. Wang, G. van der Werf, D. Wickland, M. Williams, and C. Zehner
Biogeosciences, 11, 3547–3602,
G. Turi, Z. Lachkar, and N. Gruber
Biogeosciences, 11, 671–690,
P. Landschützer, N. Gruber, D. C. E. Bakker, U. Schuster, S. Nakaoka, M. R. Payne, T. P. Sasse, and J. Zeng
Biogeosciences, 10, 7793–7815,
C. Laufkötter, M. Vogt, and N. Gruber
Biogeosciences, 10, 7373–7393,
A. Schmittner, N. Gruber, A. C. Mix, R. M. Key, A. Tagliabue, and T. K. Westberry
Biogeosciences, 10, 5793–5816,
C. J. O'Brien, J. A. Peloquin, M. Vogt, M. Heinle, N. Gruber, P. Ajani, H. Andruleit, J. Arístegui, L. Beaufort, M. Estrada, D. Karentz, E. Kopczyńska, R. Lee, A. J. Poulton, T. Pritchard, and C. Widdicombe
Earth Syst. Sci. Data, 5, 259–276,
A. Lenton, B. Tilbrook, R. M. Law, D. Bakker, S. C. Doney, N. Gruber, M. Ishii, M. Hoppema, N. S. Lovenduski, R. J. Matear, B. I. McNeil, N. Metzl, S. E. Mikaloff Fletcher, P. M. S. Monteiro, C. Rödenbeck, C. Sweeney, and T. Takahashi
Biogeosciences, 10, 4037–4054,
S. Khatiwala, T. Tanhua, S. Mikaloff Fletcher, M. Gerber, S. C. Doney, H. D. Graven, N. Gruber, G. A. McKinley, A. Murata, A. F. Ríos, and C. L. Sabine
Biogeosciences, 10, 2169–2191,
J. Peloquin, C. Swan, N. Gruber, M. Vogt, H. Claustre, J. Ras, J. Uitz, R. Barlow, M. Behrenfeld, R. Bidigare, H. Dierssen, G. Ditullio, E. Fernandez, C. Gallienne, S. Gibb, R. Goericke, L. Harding, E. Head, P. Holligan, S. Hooker, D. Karl, M. Landry, R. Letelier, C. A. Llewellyn, M. Lomas, M. Lucas, A. Mannino, J.-C. Marty, B. G. Mitchell, F. Muller-Karger, N. Nelson, C. O'Brien, B. Prezelin, D. Repeta, W. O. Jr. Smith, D. Smythe-Wright, R. Stumpf, A. Subramaniam, K. Suzuki, C. Trees, M. Vernet, N. Wasmund, and S. Wright
Earth Syst. Sci. Data, 5, 109–123,
R. Wanninkhof, G. -H. Park, T. Takahashi, C. Sweeney, R. Feely, Y. Nojiri, N. Gruber, S. C. Doney, G. A. McKinley, A. Lenton, C. Le Quéré, C. Heinze, J. Schwinger, H. Graven, and S. Khatiwala
Biogeosciences, 10, 1983–2000,
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Atlantic Water that carries heat and anthropogenic carbon into the Arctic Ocean plays an important role in the Arctic sea-ice cover decline, but its pathways and travel times remain unclear. Here we used two radionuclides of anthropogenic origin (129I and 236U) to track Atlantic-derived waters along their way through the Arctic Ocean, estimating their travel times and mixing properties. Results help to understand how future changes in Atlantic Water properties will spread through the Arctic.
Atlantic Water that carries heat and anthropogenic carbon into the Arctic Ocean plays an...