Articles | Volume 18, issue 4
https://doi.org/10.5194/bg-18-1407-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-1407-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note: Interpreting pH changes
Andrea J. Fassbender
CORRESPONDING AUTHOR
Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss
Landing, CA 95039, USA
James C. Orr
LSCE/IPSL, Laboratoire des Sciences du Climat et de l'Environnement,
CEA-CNRS-UVSQ, Gif-sur-Yvette, France
Andrew G. Dickson
Scripps Institution of Oceanography, University of California, San
Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
Related authors
Brandon Stephens, Montserrat Roca-Martí, Amy Maas, Vinícius Amaral, Samantha Clevenger, Shawnee Traylor, Claudia Benitez-Nelson, Philip Boyd, Ken Buesseler, Craig Carlson, Nicolas Cassar, Margaret Estapa, Andrea Fassbender, Yibin Huang, Phoebe Lam, Olivier Marchal, Susanne Menden-Deuer, Nicola Paul, Alyson Santoro, David Siegel, and David Nicholson
EGUsphere, https://doi.org/10.5194/egusphere-2024-2251, https://doi.org/10.5194/egusphere-2024-2251, 2024
Short summary
Short summary
The ocean’s mesopelagic zone (MZ) plays a crucial role in the global carbon cycle. This study combines new and previously published measurements of organic carbon supply and demand collected in August 2018 for the MZ in the subarctic North Pacific Ocean. Supply was insufficient to meet demand in August, but supply entering into the MZ in the spring of 2018 could have met the August demand. Results suggest observations over seasonal time scales may help to close MZ carbon budgets.
Jonathan D. Sharp, Andrea J. Fassbender, Brendan R. Carter, Gregory C. Johnson, Cristina Schultz, and John P. Dunne
Earth Syst. Sci. Data, 15, 4481–4518, https://doi.org/10.5194/essd-15-4481-2023, https://doi.org/10.5194/essd-15-4481-2023, 2023
Short summary
Short summary
Dissolved oxygen content is a critical metric of ocean health. Recently, expanding fleets of autonomous platforms that measure oxygen in the ocean have produced a wealth of new data. We leverage machine learning to take advantage of this growing global dataset, producing a gridded data product of ocean interior dissolved oxygen at monthly resolution over nearly 2 decades. This work provides novel information for investigations of spatial, seasonal, and interannual variability in ocean oxygen.
Jonathan D. Sharp, Andrea J. Fassbender, Brendan R. Carter, Paige D. Lavin, and Adrienne J. Sutton
Earth Syst. Sci. Data, 14, 2081–2108, https://doi.org/10.5194/essd-14-2081-2022, https://doi.org/10.5194/essd-14-2081-2022, 2022
Short summary
Short summary
Oceanographers calculate the exchange of carbon between the ocean and atmosphere by comparing partial pressures of carbon dioxide (pCO2). Because seawater pCO2 is not measured everywhere at all times, interpolation schemes are required to fill observational gaps. We describe a monthly gap-filled dataset of pCO2 in the northeast Pacific Ocean off the west coast of North America created by machine-learning interpolation. This dataset is unique in its robust representation of coastal seasonality.
Chiho Sukigara, Ryuichiro Inoue, Kanako Sato, Yoshihisa Mino, Takeyoshi Nagai, Andrea J. Fassbender, Yuichiro Takeshita, Stuart Bishop, and Eitarou Oka
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-9, https://doi.org/10.5194/bg-2022-9, 2022
Manuscript not accepted for further review
Short summary
Short summary
To investigate the physical changes in the ocean from winter to spring and the corresponding biological activities, two automated floats were used to conduct observations in the western North Pacific from January to April 2018. During the observation, repeated storms passed and mixed the ocean surface layer. Afterwards, active biological activity was observed. Using data from the float, we observed the formation, decomposition, and settling of particulate organic matter.
Chiho Sukigara, Ryuichiro Inoue, Kanako Sato, Yoshihisa Mino, Takeyoshi Nagai, Andrea J. Fassbender, Yuichiro Takeshita, and Eitarou Oka
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-116, https://doi.org/10.5194/bg-2021-116, 2021
Manuscript not accepted for further review
Short summary
Short summary
We combined ship-borne water sampling with the use of two Argo floats equipped with biogeochemical sensors to determine the changes in primary productivity associated with the passage of storms and resultant disturbance in the subtropical western North Pacific. We found that the episodic influx of carbon to the surface facilitated by storms played a key role in promoting primary production. Particulate carbon transported to the twilight layer were not the major substrate for the respiration.
Andrea J. Fassbender, Simone R. Alin, Richard A. Feely, Adrienne J. Sutton, Jan A. Newton, Christopher Krembs, Julia Bos, Mya Keyzers, Allan Devol, Wendi Ruef, and Greg Pelletier
Earth Syst. Sci. Data, 10, 1367–1401, https://doi.org/10.5194/essd-10-1367-2018, https://doi.org/10.5194/essd-10-1367-2018, 2018
Short summary
Short summary
Ocean acidification (OA) is difficult to identify in coastal marine waters due to the magnitude of natural variability and lack of historical baseline information. To provide regional context for ongoing research, adaptation, and management efforts, we have collated high-quality publicly available data to characterize seasonal cycles of OA-relevant parameters in the Pacific Northwest marine surface waters. Large nonstationary chemical gradients from the open ocean into the Salish Sea are found.
Brandon Stephens, Montserrat Roca-Martí, Amy Maas, Vinícius Amaral, Samantha Clevenger, Shawnee Traylor, Claudia Benitez-Nelson, Philip Boyd, Ken Buesseler, Craig Carlson, Nicolas Cassar, Margaret Estapa, Andrea Fassbender, Yibin Huang, Phoebe Lam, Olivier Marchal, Susanne Menden-Deuer, Nicola Paul, Alyson Santoro, David Siegel, and David Nicholson
EGUsphere, https://doi.org/10.5194/egusphere-2024-2251, https://doi.org/10.5194/egusphere-2024-2251, 2024
Short summary
Short summary
The ocean’s mesopelagic zone (MZ) plays a crucial role in the global carbon cycle. This study combines new and previously published measurements of organic carbon supply and demand collected in August 2018 for the MZ in the subarctic North Pacific Ocean. Supply was insufficient to meet demand in August, but supply entering into the MZ in the spring of 2018 could have met the August demand. Results suggest observations over seasonal time scales may help to close MZ carbon budgets.
Nina Bednaršek, Greg Pelletier, Hanna van de Mortel, Marisol García-Reyes, Richard Feely, and Andrew Dickson
EGUsphere, https://doi.org/10.5194/egusphere-2024-947, https://doi.org/10.5194/egusphere-2024-947, 2024
Short summary
Short summary
The environmental impacts of ocean alkalinity enhancement (OAE) are unknown. A conceptual framework was developed showing 40 % of species to respond positively, 20 % negatively and 40 % with neutral response upon alkalinity addition. Biological thresholds were found between 10 to 500 µmol/kg NaOH addition, emphasizing lab experiments to be conducted at lower dosages. A precautionary approach is warranted to avoid potential risks.
Kai G. Schulz, Lennart T. Bach, and Andrew G. Dickson
State Planet, 2-oae2023, 2, https://doi.org/10.5194/sp-2-oae2023-2-2023, https://doi.org/10.5194/sp-2-oae2023-2-2023, 2023
Short summary
Short summary
Ocean alkalinity enhancement is a promising approach for long-term anthropogenic carbon dioxide sequestration, required to avoid catastrophic climate change. In this chapter we describe its impacts on seawater carbonate chemistry speciation and highlight pitfalls that need to be avoided during sampling, storage, measurements, and calculations.
Jonathan D. Sharp, Andrea J. Fassbender, Brendan R. Carter, Gregory C. Johnson, Cristina Schultz, and John P. Dunne
Earth Syst. Sci. Data, 15, 4481–4518, https://doi.org/10.5194/essd-15-4481-2023, https://doi.org/10.5194/essd-15-4481-2023, 2023
Short summary
Short summary
Dissolved oxygen content is a critical metric of ocean health. Recently, expanding fleets of autonomous platforms that measure oxygen in the ocean have produced a wealth of new data. We leverage machine learning to take advantage of this growing global dataset, producing a gridded data product of ocean interior dissolved oxygen at monthly resolution over nearly 2 decades. This work provides novel information for investigations of spatial, seasonal, and interannual variability in ocean oxygen.
Jonathan D. Sharp, Andrea J. Fassbender, Brendan R. Carter, Paige D. Lavin, and Adrienne J. Sutton
Earth Syst. Sci. Data, 14, 2081–2108, https://doi.org/10.5194/essd-14-2081-2022, https://doi.org/10.5194/essd-14-2081-2022, 2022
Short summary
Short summary
Oceanographers calculate the exchange of carbon between the ocean and atmosphere by comparing partial pressures of carbon dioxide (pCO2). Because seawater pCO2 is not measured everywhere at all times, interpolation schemes are required to fill observational gaps. We describe a monthly gap-filled dataset of pCO2 in the northeast Pacific Ocean off the west coast of North America created by machine-learning interpolation. This dataset is unique in its robust representation of coastal seasonality.
Chiho Sukigara, Ryuichiro Inoue, Kanako Sato, Yoshihisa Mino, Takeyoshi Nagai, Andrea J. Fassbender, Yuichiro Takeshita, Stuart Bishop, and Eitarou Oka
Biogeosciences Discuss., https://doi.org/10.5194/bg-2022-9, https://doi.org/10.5194/bg-2022-9, 2022
Manuscript not accepted for further review
Short summary
Short summary
To investigate the physical changes in the ocean from winter to spring and the corresponding biological activities, two automated floats were used to conduct observations in the western North Pacific from January to April 2018. During the observation, repeated storms passed and mixed the ocean surface layer. Afterwards, active biological activity was observed. Using data from the float, we observed the formation, decomposition, and settling of particulate organic matter.
Chiho Sukigara, Ryuichiro Inoue, Kanako Sato, Yoshihisa Mino, Takeyoshi Nagai, Andrea J. Fassbender, Yuichiro Takeshita, and Eitarou Oka
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-116, https://doi.org/10.5194/bg-2021-116, 2021
Manuscript not accepted for further review
Short summary
Short summary
We combined ship-borne water sampling with the use of two Argo floats equipped with biogeochemical sensors to determine the changes in primary productivity associated with the passage of storms and resultant disturbance in the subtropical western North Pacific. We found that the episodic influx of carbon to the surface facilitated by storms played a key role in promoting primary production. Particulate carbon transported to the twilight layer were not the major substrate for the respiration.
Lester Kwiatkowski, Olivier Torres, Laurent Bopp, Olivier Aumont, Matthew Chamberlain, James R. Christian, John P. Dunne, Marion Gehlen, Tatiana Ilyina, Jasmin G. John, Andrew Lenton, Hongmei Li, Nicole S. Lovenduski, James C. Orr, Julien Palmieri, Yeray Santana-Falcón, Jörg Schwinger, Roland Séférian, Charles A. Stock, Alessandro Tagliabue, Yohei Takano, Jerry Tjiputra, Katsuya Toyama, Hiroyuki Tsujino, Michio Watanabe, Akitomo Yamamoto, Andrew Yool, and Tilo Ziehn
Biogeosciences, 17, 3439–3470, https://doi.org/10.5194/bg-17-3439-2020, https://doi.org/10.5194/bg-17-3439-2020, 2020
Short summary
Short summary
We assess 21st century projections of marine biogeochemistry in the CMIP6 Earth system models. These models represent the most up-to-date understanding of climate change. The models generally project greater surface ocean warming, acidification, subsurface deoxygenation, and euphotic nitrate reductions but lesser primary production declines than the previous generation of models. This has major implications for the impact of anthropogenic climate change on marine ecosystems.
Jens Terhaar, James C. Orr, Marion Gehlen, Christian Ethé, and Laurent Bopp
Biogeosciences, 16, 2343–2367, https://doi.org/10.5194/bg-16-2343-2019, https://doi.org/10.5194/bg-16-2343-2019, 2019
Short summary
Short summary
A budget of anthropogenic carbon in the Arctic Ocean, the main driver of open-ocean acidification, was constructed for the first time using a high-resolution ocean model. The budget reveals that anthropogenic carbon enters the Arctic Ocean mainly by lateral transport; the air–sea flux plays a minor role. Coarser-resolution versions of the same model, typical of earth system models, store less anthropogenic carbon in the Arctic Ocean and thus underestimate ocean acidification in the Arctic Ocean.
Camille Richon, Jean-Claude Dutay, Laurent Bopp, Briac Le Vu, James C. Orr, Samuel Somot, and François Dulac
Biogeosciences, 16, 135–165, https://doi.org/10.5194/bg-16-135-2019, https://doi.org/10.5194/bg-16-135-2019, 2019
Short summary
Short summary
We evaluate the effects of climate change and biogeochemical forcing evolution on the nutrient and plankton cycles of the Mediterranean Sea for the first time. We use a high-resolution coupled physical and biogeochemical model and perform 120-year transient simulations. The results indicate that changes in external nutrient fluxes and climate change may have synergistic or antagonistic effects on nutrient concentrations, depending on the region and the scenario.
Andrea J. Fassbender, Simone R. Alin, Richard A. Feely, Adrienne J. Sutton, Jan A. Newton, Christopher Krembs, Julia Bos, Mya Keyzers, Allan Devol, Wendi Ruef, and Greg Pelletier
Earth Syst. Sci. Data, 10, 1367–1401, https://doi.org/10.5194/essd-10-1367-2018, https://doi.org/10.5194/essd-10-1367-2018, 2018
Short summary
Short summary
Ocean acidification (OA) is difficult to identify in coastal marine waters due to the magnitude of natural variability and lack of historical baseline information. To provide regional context for ongoing research, adaptation, and management efforts, we have collated high-quality publicly available data to characterize seasonal cycles of OA-relevant parameters in the Pacific Northwest marine surface waters. Large nonstationary chemical gradients from the open ocean into the Salish Sea are found.
James C. Orr, Raymond G. Najjar, Olivier Aumont, Laurent Bopp, John L. Bullister, Gokhan Danabasoglu, Scott C. Doney, John P. Dunne, Jean-Claude Dutay, Heather Graven, Stephen M. Griffies, Jasmin G. John, Fortunat Joos, Ingeborg Levin, Keith Lindsay, Richard J. Matear, Galen A. McKinley, Anne Mouchet, Andreas Oschlies, Anastasia Romanou, Reiner Schlitzer, Alessandro Tagliabue, Toste Tanhua, and Andrew Yool
Geosci. Model Dev., 10, 2169–2199, https://doi.org/10.5194/gmd-10-2169-2017, https://doi.org/10.5194/gmd-10-2169-2017, 2017
Short summary
Short summary
The Ocean Model Intercomparison Project (OMIP) is a model comparison effort under Phase 6 of the Coupled Model Intercomparison Project (CMIP6). Its physical component is described elsewhere in this special issue. Here we describe its ocean biogeochemical component (OMIP-BGC), detailing simulation protocols and analysis diagnostics. Simulations focus on ocean carbon, other biogeochemical tracers, air-sea exchange of CO2 and related gases, and chemical tracers used to evaluate modeled circulation.
Stephen M. Griffies, Gokhan Danabasoglu, Paul J. Durack, Alistair J. Adcroft, V. Balaji, Claus W. Böning, Eric P. Chassignet, Enrique Curchitser, Julie Deshayes, Helge Drange, Baylor Fox-Kemper, Peter J. Gleckler, Jonathan M. Gregory, Helmuth Haak, Robert W. Hallberg, Patrick Heimbach, Helene T. Hewitt, David M. Holland, Tatiana Ilyina, Johann H. Jungclaus, Yoshiki Komuro, John P. Krasting, William G. Large, Simon J. Marsland, Simona Masina, Trevor J. McDougall, A. J. George Nurser, James C. Orr, Anna Pirani, Fangli Qiao, Ronald J. Stouffer, Karl E. Taylor, Anne Marie Treguier, Hiroyuki Tsujino, Petteri Uotila, Maria Valdivieso, Qiang Wang, Michael Winton, and Stephen G. Yeager
Geosci. Model Dev., 9, 3231–3296, https://doi.org/10.5194/gmd-9-3231-2016, https://doi.org/10.5194/gmd-9-3231-2016, 2016
Short summary
Short summary
The Ocean Model Intercomparison Project (OMIP) aims to provide a framework for evaluating, understanding, and improving the ocean and sea-ice components of global climate and earth system models contributing to the Coupled Model Intercomparison Project Phase 6 (CMIP6). This document defines OMIP and details a protocol both for simulating global ocean/sea-ice models and for analysing their output.
Timothée Bourgeois, James C. Orr, Laure Resplandy, Jens Terhaar, Christian Ethé, Marion Gehlen, and Laurent Bopp
Biogeosciences, 13, 4167–4185, https://doi.org/10.5194/bg-13-4167-2016, https://doi.org/10.5194/bg-13-4167-2016, 2016
Short summary
Short summary
The global coastal ocean took up 0.1 Pg C yr−1 of anthropogenic carbon during 1993–2012 based on new biogeochemical simulations with an eddying 3-D global model. That is about half of the most recent estimate, an extrapolation based on surface areas. It should not be confused with the continental shelf pump, perhaps 10 times larger, which includes natural as well as anthropogenic carbon. Coastal uptake of anthropogenic carbon is limited by its offshore transport.
Roland Séférian, Marion Gehlen, Laurent Bopp, Laure Resplandy, James C. Orr, Olivier Marti, John P. Dunne, James R. Christian, Scott C. Doney, Tatiana Ilyina, Keith Lindsay, Paul R. Halloran, Christoph Heinze, Joachim Segschneider, Jerry Tjiputra, Olivier Aumont, and Anastasia Romanou
Geosci. Model Dev., 9, 1827–1851, https://doi.org/10.5194/gmd-9-1827-2016, https://doi.org/10.5194/gmd-9-1827-2016, 2016
Short summary
Short summary
This paper explores how the large diversity in spin-up protocols used for ocean biogeochemistry in CMIP5 models contributed to inter-model differences in modeled fields. We show that a link between spin-up duration and skill-score metrics emerges from both individual IPSL-CM5A-LR's results and an ensemble of CMIP5 models. Our study suggests that differences in spin-up protocols constitute a source of inter-model uncertainty which would require more attention in future intercomparison exercises.
J. C. Orr, J.-M. Epitalon, and J.-P. Gattuso
Biogeosciences, 12, 1483–1510, https://doi.org/10.5194/bg-12-1483-2015, https://doi.org/10.5194/bg-12-1483-2015, 2015
Short summary
Short summary
Basic marine carbonate system variables such as pH are often computed from others. Such calculations are made with many public software packages, but their results have never been compared. A new study compares 10 of these packages, quantifying differences, isolating causes, and making recommendations to reduce future discrepancies. This comparison effort has led to more than a 10-fold reduction in differences between packages for some computed variables.
J. C. Orr and J.-M. Epitalon
Geosci. Model Dev., 8, 485–499, https://doi.org/10.5194/gmd-8-485-2015, https://doi.org/10.5194/gmd-8-485-2015, 2015
Short summary
Short summary
We provide improved routines to model the ocean carbonate system, i.e., to compute ocean pH and related variables from dissolved inorganic carbon and total alkalinity. These routines (1) rely on the fastest available algorithm to solve the alkalinity-pH equation, which converges even under extreme conditions; (2) avoid common model approximations that lead to errors of 3% or more in computed variables; and (3) account for large pressure effects on subsurface pCO2, unlike other packages.
J. Palmiéri, J. C. Orr, J.-C. Dutay, K. Béranger, A. Schneider, J. Beuvier, and S. Somot
Biogeosciences, 12, 781–802, https://doi.org/10.5194/bg-12-781-2015, https://doi.org/10.5194/bg-12-781-2015, 2015
Short summary
Short summary
Different observational-based estimates of CO2 uptake and resulting
acidification of the Mediterranean Sea vary widely. A new study finds
that even the smallest of those are an upper limit because the approach
used assumes air-sea CO2 equilibrium. Then with a lower limit from new
fine-scale numerical model simulations, the authors bracket
Mediterranean Sea CO2 uptake and acidification rates. They conclude that
its rate of surface acidifcation is much like that for typical ocean
waters.
M. Gehlen, R. Séférian, D. O. B. Jones, T. Roy, R. Roth, J. Barry, L. Bopp, S. C. Doney, J. P. Dunne, C. Heinze, F. Joos, J. C. Orr, L. Resplandy, J. Segschneider, and J. Tjiputra
Biogeosciences, 11, 6955–6967, https://doi.org/10.5194/bg-11-6955-2014, https://doi.org/10.5194/bg-11-6955-2014, 2014
Short summary
Short summary
This study evaluates potential impacts of pH reductions on North Atlantic deep-sea ecosystems in response to latest IPCC scenarios.Multi-model projections of pH changes over the seafloor are analysed with reference to a critical threshold based on palaeo-oceanographic studies, contemporary observations and model results. By 2100 under the most severe IPCC CO2 scenario, pH reductions occur over ~23% of deep-sea canyons and ~8% of seamounts – including seamounts proposed as marine protected areas.
L. Bopp, L. Resplandy, J. C. Orr, S. C. Doney, J. P. Dunne, M. Gehlen, P. Halloran, C. Heinze, T. Ilyina, R. Séférian, J. Tjiputra, and M. Vichi
Biogeosciences, 10, 6225–6245, https://doi.org/10.5194/bg-10-6225-2013, https://doi.org/10.5194/bg-10-6225-2013, 2013
E. E. Bockmon, C. A. Frieder, M. O. Navarro, L. A. White-Kershek, and A. G. Dickson
Biogeosciences, 10, 5967–5975, https://doi.org/10.5194/bg-10-5967-2013, https://doi.org/10.5194/bg-10-5967-2013, 2013
V. Cocco, F. Joos, M. Steinacher, T. L. Frölicher, L. Bopp, J. Dunne, M. Gehlen, C. Heinze, J. Orr, A. Oschlies, B. Schneider, J. Segschneider, and J. Tjiputra
Biogeosciences, 10, 1849–1868, https://doi.org/10.5194/bg-10-1849-2013, https://doi.org/10.5194/bg-10-1849-2013, 2013
Related subject area
Earth System Science/Response to Global Change: Climate Change
Effect of terrestrial nutrient limitation on the estimation of the remaining carbon budget
Projected changes in forest fire season, the number of fires, and burnt area in Fennoscandia by 2100
New ozone–nitrogen model shows early senescence onset is the primary cause of ozone-induced reduction in grain quality of wheat
Ocean alkalinity enhancement approaches and the predictability of runaway precipitation processes: results of an experimental study to determine critical alkalinity ranges for safe and sustainable application scenarios
Variations of polyphenols and carbohydrates of Emiliania huxleyi grown under simulated ocean acidification conditions
Global and regional hydrological impacts of global forest expansion
The biological and preformed carbon pumps in perpetually slower and warmer oceans
The Southern Ocean as the climate's freight train – driving ongoing global warming under zero-emission scenarios with ACCESS-ESM1.5
Mapping the future afforestation distribution of China constrained by a national afforestation plan and climate change
Southern Ocean phytoplankton under climate change: a shifting balance of bottom-up and top-down control
Coherency and time lag analyses between MODIS vegetation indices and climate across forests and grasslands in the European temperate zone
Direct foliar phosphorus uptake from wildfire ash
Unifying framework for assessing sensitivity for marine calcifiers to ocean alkalinity enhancement identifies winners, losers and biological thresholds – importance of caution with precautionary principle
Effect of the 2022 summer drought across forest types in Europe
The effect of forest cover changes on the regional climate conditions in Europe during the period 1986–2015
Carbon cycle feedbacks in an idealized simulation and a scenario simulation of negative emissions in CMIP6 Earth system models
Responses of field-grown maize to different soil types, water regimes, and contrasting vapor pressure deficit
Spatiotemporal heterogeneity in the increase in ocean acidity extremes in the northeastern Pacific
Particle fluxes by subtropical pelagic communities under ocean alkalinity enhancement
Anthropogenic climate change drives non-stationary phytoplankton internal variability
The response of wildfire regimes to Last Glacial Maximum carbon dioxide and climate
Simulated responses of soil carbon to climate change in CMIP6 Earth system models: the role of false priming
Alkalinity biases in CMIP6 Earth system models and implications for simulated CO2 drawdown via artificial alkalinity enhancement
Experiments of the efficacy of tree ring blue intensity as a climate proxy in central and western China
Burned area and carbon emissions across northwestern boreal North America from 2001–2019
Quantifying land carbon cycle feedbacks under negative CO2 emissions
The potential of an increased deciduous forest fraction to mitigate the effects of heat extremes in Europe
Ideas and perspectives: Alleviation of functional limitations by soil organisms is key to climate feedbacks from arctic soils
A comparison of the climate and carbon cycle effects of carbon removal by afforestation and an equivalent reduction in fossil fuel emissions
Stability of alkalinity in ocean alkalinity enhancement (OAE) approaches – consequences for durability of CO2 storage
Ideas and perspectives: Land–ocean connectivity through groundwater
Bioclimatic change as a function of global warming from CMIP6 climate projections
Reconciling different approaches to quantifying land surface temperature impacts of afforestation using satellite observations
Drivers of intermodel uncertainty in land carbon sink projections
Reviews and syntheses: A framework to observe, understand and project ecosystem response to environmental change in the East Antarctic Southern Ocean
Acidification impacts and acclimation potential of Caribbean benthic foraminifera assemblages in naturally discharging low-pH water
Monitoring vegetation condition using microwave remote sensing: the standardized vegetation optical depth index (SVODI)
Evaluation of soil carbon simulation in CMIP6 Earth system models
Diazotrophy as a key driver of the response of marine net primary productivity to climate change
Impact of negative and positive CO2 emissions on global warming metrics using an ensemble of Earth system model simulations
Acidification, deoxygenation, and nutrient and biomass declines in a warming Mediterranean Sea
Ocean alkalinity enhancement – avoiding runaway CaCO3 precipitation during quick and hydrated lime dissolution
Assessment of the impacts of biological nitrogen fixation structural uncertainty in CMIP6 earth system models
Soil carbon loss in warmed subarctic grasslands is rapid and restricted to topsoil
The European forest carbon budget under future climate conditions and current management practices
The influence of mesoscale climate drivers on hypoxia in a fjord-like deep coastal inlet and its potential implications regarding climate change: examining a decade of water quality data
Contrasting responses of phytoplankton productivity between coastal and offshore surface waters in the Taiwan Strait and the South China Sea to short-term seawater acidification
Modeling interactions between tides, storm surges, and river discharges in the Kapuas River delta
The application of dendrometers to alpine dwarf shrubs – a case study to investigate stem growth responses to environmental conditions
Climate, land cover and topography: essential ingredients in predicting wetland permanence
Makcim L. De Sisto and Andrew H. MacDougall
Biogeosciences, 21, 4853–4873, https://doi.org/10.5194/bg-21-4853-2024, https://doi.org/10.5194/bg-21-4853-2024, 2024
Short summary
Short summary
The remaining carbon budget (RCB) represents the allowable future CO2 emissions before a temperature target is reached. Understanding the uncertainty in the RCB is critical for effective climate regulation and policy-making. One major source of uncertainty is the representation of the carbon cycle in Earth system models. We assessed how nutrient limitation affects the estimation of the RCB. We found a reduction in the estimated RCB when nutrient limitation is taken into account.
Outi Kinnunen, Leif Backman, Juha Aalto, Tuula Aalto, and Tiina Markkanen
Biogeosciences, 21, 4739–4763, https://doi.org/10.5194/bg-21-4739-2024, https://doi.org/10.5194/bg-21-4739-2024, 2024
Short summary
Short summary
Climate change is expected to increase the risk of forest fires. Ecosystem process model simulations are used to project changes in fire occurrence in Fennoscandia under six climate projections. The findings suggest a longer fire season, more fires, and an increase in burnt area towards the end of the century.
Jo Cook, Clare Brewster, Felicity Hayes, Nathan Booth, Sam Bland, Pritha Pande, Samarthia Thankappan, Håkan Pleijel, and Lisa Emberson
Biogeosciences, 21, 4809–4835, https://doi.org/10.5194/bg-21-4809-2024, https://doi.org/10.5194/bg-21-4809-2024, 2024
Short summary
Short summary
At ground level, the air pollutant ozone (O3) damages wheat yield and quality. We modified the DO3SE-Crop model to simulate O3 effects on wheat quality and identified onset of leaf death as the key process affecting wheat quality upon O3 exposure. This aligns with expectations, as the onset of leaf death aids nutrient transfer from leaves to grains. Breeders should prioritize wheat varieties resistant to protein loss from delayed leaf death, to maintain yield and quality under O3 exposure.
Niels Suitner, Giulia Faucher, Carl Lim, Julieta Schneider, Charly A. Moras, Ulf Riebesell, and Jens Hartmann
Biogeosciences, 21, 4587–4604, https://doi.org/10.5194/bg-21-4587-2024, https://doi.org/10.5194/bg-21-4587-2024, 2024
Short summary
Short summary
Recent studies described the precipitation of carbonates as a result of alkalinity enhancement in seawater, which could adversely affect the carbon sequestration potential of ocean alkalinity enhancement (OAE) approaches. By conducting experiments in natural seawater, this study observed uniform patterns during the triggered runaway carbonate precipitation, which allow the prediction of safe and efficient local application levels of OAE scenarios.
Milagros Rico, Paula Santiago-Díaz, Guillermo Samperio-Ramos, Melchor González-Dávila, and Juana Magdalena Santana-Casiano
Biogeosciences, 21, 4381–4394, https://doi.org/10.5194/bg-21-4381-2024, https://doi.org/10.5194/bg-21-4381-2024, 2024
Short summary
Short summary
Changes in pH generate stress conditions, either because high pH drastically decreases the availability of trace metals such as Fe(II), a restrictive element for primary productivity, or because reactive oxygen species are increased with low pH. The metabolic functions and composition of microalgae can be affected. These modifications in metabolites are potential factors leading to readjustments in phytoplankton community structure and diversity and possible alteration in marine ecosystems.
James A. King, James Weber, Peter Lawrence, Stephanie Roe, Abigail L. S. Swann, and Maria Val Martin
Biogeosciences, 21, 3883–3902, https://doi.org/10.5194/bg-21-3883-2024, https://doi.org/10.5194/bg-21-3883-2024, 2024
Short summary
Short summary
Tackling climate change by adding, restoring, or enhancing forests is gaining global support. However, it is important to investigate the broader implications of this. We used a computer model of the Earth to investigate a future where tree cover expanded as much as possible. We found that some tropical areas were cooler because of trees pumping water into the atmosphere, but this also led to soil and rivers drying. This is important because it might be harder to maintain forests as a result.
Benoît Pasquier, Mark Holzer, and Matthew A. Chamberlain
Biogeosciences, 21, 3373–3400, https://doi.org/10.5194/bg-21-3373-2024, https://doi.org/10.5194/bg-21-3373-2024, 2024
Short summary
Short summary
How do perpetually slower and warmer oceans sequester carbon? Compared to the preindustrial state, we find that biological productivity declines despite warming-stimulated growth because of a lower nutrient supply from depth. This throttles the biological carbon pump, which still sequesters more carbon because it takes longer to return to the surface. The deep ocean is isolated from the surface, allowing more carbon from the atmosphere to pass through the ocean without contributing to biology.
Matthew A. Chamberlain, Tilo Ziehn, and Rachel M. Law
Biogeosciences, 21, 3053–3073, https://doi.org/10.5194/bg-21-3053-2024, https://doi.org/10.5194/bg-21-3053-2024, 2024
Short summary
Short summary
This paper explores the climate processes that drive increasing global average temperatures in zero-emission commitment (ZEC) simulations despite decreasing atmospheric CO2. ACCESS-ESM1.5 shows the Southern Ocean to continue to warm locally in all ZEC simulations. In ZEC simulations that start after the emission of more than 1000 Pg of carbon, the influence of the Southern Ocean increases the global temperature.
Shuaifeng Song, Xuezhen Zhang, and Xiaodong Yan
Biogeosciences, 21, 2839–2858, https://doi.org/10.5194/bg-21-2839-2024, https://doi.org/10.5194/bg-21-2839-2024, 2024
Short summary
Short summary
We mapped the distribution of future potential afforestation regions based on future high-resolution climate data and climate–vegetation models. After considering the national afforestation policy and climate change, we found that the future potential afforestation region was mainly located around and to the east of the Hu Line. This study provides a dataset for exploring the effects of future afforestation.
Tianfei Xue, Jens Terhaar, A. E. Friederike Prowe, Thomas L. Frölicher, Andreas Oschlies, and Ivy Frenger
Biogeosciences, 21, 2473–2491, https://doi.org/10.5194/bg-21-2473-2024, https://doi.org/10.5194/bg-21-2473-2024, 2024
Short summary
Short summary
Phytoplankton play a crucial role in marine ecosystems. However, climate change's impact on phytoplankton biomass remains uncertain, particularly in the Southern Ocean. In this region, phytoplankton biomass within the water column is likely to remain stable in response to climate change, as supported by models. This stability arises from a shallower mixed layer, favoring phytoplankton growth but also increasing zooplankton grazing due to phytoplankton concentration near the surface.
Kinga Kulesza and Agata Hościło
Biogeosciences, 21, 2509–2527, https://doi.org/10.5194/bg-21-2509-2024, https://doi.org/10.5194/bg-21-2509-2024, 2024
Short summary
Short summary
We present coherence and time lags in spectral response of three vegetation types in the European temperate zone to the influencing meteorological factors and teleconnection indices for the period 2002–2022. Vegetation condition in broadleaved forest, coniferous forest and pastures was measured with MODIS NDVI and EVI, and the coherence between NDVI and EVI and meteorological elements was described using the methods of wavelet coherence and Pearson’s linear correlation with time lag.
Anton Lokshin, Daniel Palchan, and Avner Gross
Biogeosciences, 21, 2355–2365, https://doi.org/10.5194/bg-21-2355-2024, https://doi.org/10.5194/bg-21-2355-2024, 2024
Short summary
Short summary
Ash particles from wildfires are rich in phosphorus (P), a crucial nutrient that constitutes a limiting factor in 43 % of the world's land ecosystems. We hypothesize that wildfire ash could directly contribute to plant nutrition. We find that fire ash application boosts the growth of plants, but the only way plants can uptake P from fire ash is through the foliar uptake pathway and not through the roots. The fertilization impact of fire ash was also maintained under elevated levels of CO2.
Nina Bednaršek, Greg Pelletier, Hanna van de Mortel, Marisol García-Reyes, Richard Feely, and Andrew Dickson
EGUsphere, https://doi.org/10.5194/egusphere-2024-947, https://doi.org/10.5194/egusphere-2024-947, 2024
Short summary
Short summary
The environmental impacts of ocean alkalinity enhancement (OAE) are unknown. A conceptual framework was developed showing 40 % of species to respond positively, 20 % negatively and 40 % with neutral response upon alkalinity addition. Biological thresholds were found between 10 to 500 µmol/kg NaOH addition, emphasizing lab experiments to be conducted at lower dosages. A precautionary approach is warranted to avoid potential risks.
Mana Gharun, Ankit Shekhar, Jingfeng Xiao, Xing Li, and Nina Buchmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-423, https://doi.org/10.5194/egusphere-2024-423, 2024
Short summary
Short summary
In 2022, Europe's forests faced unprecedented dry conditions. Our study aimed to understand how different forest types respond to extreme drought. Using meteorological data and satellite imagery, we compared 2022 with two previous extreme years, 2003 and 2018. Despite less severe drought in 2022, forests showed a 30 % greater decline in photosynthesis compared to 2018 and 60 % more than 2003. This suggests a concerning trend of declining forest resilience to more frequent droughts.
Marcus Breil, Vanessa K. M. Schneider, and Joaquim G. Pinto
Biogeosciences, 21, 811–824, https://doi.org/10.5194/bg-21-811-2024, https://doi.org/10.5194/bg-21-811-2024, 2024
Short summary
Short summary
The general impact of afforestation on the regional climate conditions in Europe during the period 1986–2015 is investigated. For this purpose, a regional climate model simulation is performed, in which afforestation during this period is considered, and results are compared to a simulation in which this is not the case. Results show that afforestation had discernible impacts on the climate change signal in Europe, which may have mitigated the local warming trend, especially in summer in Europe.
Ali Asaadi, Jörg Schwinger, Hanna Lee, Jerry Tjiputra, Vivek Arora, Roland Séférian, Spencer Liddicoat, Tomohiro Hajima, Yeray Santana-Falcón, and Chris D. Jones
Biogeosciences, 21, 411–435, https://doi.org/10.5194/bg-21-411-2024, https://doi.org/10.5194/bg-21-411-2024, 2024
Short summary
Short summary
Carbon cycle feedback metrics are employed to assess phases of positive and negative CO2 emissions. When emissions become negative, we find that the model disagreement in feedback metrics increases more strongly than expected from the assumption that the uncertainties accumulate linearly with time. The geographical patterns of such metrics over land highlight that differences in response between tropical/subtropical and temperate/boreal ecosystems are a major source of model disagreement.
Thuy Huu Nguyen, Thomas Gaiser, Jan Vanderborght, Andrea Schnepf, Felix Bauer, Anja Klotzsche, Lena Lärm, Hubert Hüging, and Frank Ewert
EGUsphere, https://doi.org/10.5194/egusphere-2023-2967, https://doi.org/10.5194/egusphere-2023-2967, 2024
Short summary
Short summary
Leaf water potential was at certain thresholds which depends on soil types, water treatment, and weather conditions. In rainfed plot, the lower water availability in the stony soil resulted in less roots with a higher root tissue conductance than the silty soil. In silty soil, higher stress in the rainfed soil led to more roots with a lower root tissue conductance than in the irrigated plot. Crop responses to water stress can be opposite depending on soil water conditions that are compared.
Flora Desmet, Matthias Münnich, and Nicolas Gruber
Biogeosciences, 20, 5151–5175, https://doi.org/10.5194/bg-20-5151-2023, https://doi.org/10.5194/bg-20-5151-2023, 2023
Short summary
Short summary
Ocean acidity extremes in the upper 250 m depth of the northeastern Pacific rapidly increase with atmospheric CO2 rise, which is worrisome for marine organisms that rapidly experience pH levels outside their local environmental conditions. Presented research shows the spatiotemporal heterogeneity in this increase between regions and depths. In particular, the subsurface increase is substantially slowed down by the presence of mesoscale eddies, often not resolved in Earth system models.
Philipp Suessle, Jan Taucher, Silvan Goldenberg, Moritz Baumann, Kristian Spilling, Andrea Noche-Ferreira, Mari Vanharanta, and Ulf Riebesell
EGUsphere, https://doi.org/10.5194/egusphere-2023-2800, https://doi.org/10.5194/egusphere-2023-2800, 2023
Short summary
Short summary
Ocean alkalinity enhancement (OAE) is a negative emission technology which may alter marine communities and the particle export they drive. Here, impacts of carbonate-based OAE on the flux and attenuation of sinking particles in an oligotrophic plankton community are presented. Whilst biological parameters remained unaffected, abiotic carbonate precipitation occurred. Among counteracting OAE’s efficiency, it influenced mineral ballasting and particle sinking velocities, requiring monitoring.
Geneviève W. Elsworth, Nicole S. Lovenduski, Kristen M. Krumhardt, Thomas M. Marchitto, and Sarah Schlunegger
Biogeosciences, 20, 4477–4490, https://doi.org/10.5194/bg-20-4477-2023, https://doi.org/10.5194/bg-20-4477-2023, 2023
Short summary
Short summary
Anthropogenic climate change will influence marine phytoplankton over the coming century. Here, we quantify the influence of anthropogenic climate change on marine phytoplankton internal variability using an Earth system model ensemble and identify a decline in global phytoplankton biomass variance with warming. Our results suggest that climate mitigation efforts that account for marine phytoplankton changes should also consider changes in phytoplankton variance driven by anthropogenic warming.
Olivia Haas, Iain Colin Prentice, and Sandy P. Harrison
Biogeosciences, 20, 3981–3995, https://doi.org/10.5194/bg-20-3981-2023, https://doi.org/10.5194/bg-20-3981-2023, 2023
Short summary
Short summary
We quantify the impact of CO2 and climate on global patterns of burnt area, fire size, and intensity under Last Glacial Maximum (LGM) conditions using three climate scenarios. Climate change alone did not produce the observed LGM reduction in burnt area, but low CO2 did through reducing vegetation productivity. Fire intensity was sensitive to CO2 but strongly affected by changes in atmospheric dryness. Low CO2 caused smaller fires; climate had the opposite effect except in the driest scenario.
Rebecca M. Varney, Sarah E. Chadburn, Eleanor J. Burke, Simon Jones, Andy J. Wiltshire, and Peter M. Cox
Biogeosciences, 20, 3767–3790, https://doi.org/10.5194/bg-20-3767-2023, https://doi.org/10.5194/bg-20-3767-2023, 2023
Short summary
Short summary
This study evaluates soil carbon projections during the 21st century in CMIP6 Earth system models. In general, we find a reduced spread of changes in global soil carbon in CMIP6 compared to the previous CMIP5 generation. The reduced CMIP6 spread arises from an emergent relationship between soil carbon changes due to change in plant productivity and soil carbon changes due to changes in turnover time. We show that this relationship is consistent with false priming under transient climate change.
Claudia Hinrichs, Peter Köhler, Christoph Völker, and Judith Hauck
Biogeosciences, 20, 3717–3735, https://doi.org/10.5194/bg-20-3717-2023, https://doi.org/10.5194/bg-20-3717-2023, 2023
Short summary
Short summary
This study evaluated the alkalinity distribution in 14 climate models and found that most models underestimate alkalinity at the surface and overestimate it in the deeper ocean. It highlights the need for better understanding and quantification of processes driving alkalinity distribution and calcium carbonate dissolution and the importance of accounting for biases in model results when evaluating potential ocean alkalinity enhancement experiments.
Yonghong Zheng, Huanfeng Shen, Rory Abernethy, and Rob Wilson
Biogeosciences, 20, 3481–3490, https://doi.org/10.5194/bg-20-3481-2023, https://doi.org/10.5194/bg-20-3481-2023, 2023
Short summary
Short summary
Investigations in central and western China show that tree ring inverted latewood intensity expresses a strong positive relationship with growing-season temperatures, indicating exciting potential for regions south of 30° N that are traditionally not targeted for temperature reconstructions. Earlywood BI also shows good potential to reconstruct hydroclimate parameters in some humid areas and will enhance ring-width-based hydroclimate reconstructions in the future.
Stefano Potter, Sol Cooperdock, Sander Veraverbeke, Xanthe Walker, Michelle C. Mack, Scott J. Goetz, Jennifer Baltzer, Laura Bourgeau-Chavez, Arden Burrell, Catherine Dieleman, Nancy French, Stijn Hantson, Elizabeth E. Hoy, Liza Jenkins, Jill F. Johnstone, Evan S. Kane, Susan M. Natali, James T. Randerson, Merritt R. Turetsky, Ellen Whitman, Elizabeth Wiggins, and Brendan M. Rogers
Biogeosciences, 20, 2785–2804, https://doi.org/10.5194/bg-20-2785-2023, https://doi.org/10.5194/bg-20-2785-2023, 2023
Short summary
Short summary
Here we developed a new burned-area detection algorithm between 2001–2019 across Alaska and Canada at 500 m resolution. We estimate 2.37 Mha burned annually between 2001–2019 over the domain, emitting 79.3 Tg C per year, with a mean combustion rate of 3.13 kg C m−2. We found larger-fire years were generally associated with greater mean combustion. The burned-area and combustion datasets described here can be used for local- to continental-scale applications of boreal fire science.
V. Rachel Chimuka, Claude-Michel Nzotungicimpaye, and Kirsten Zickfeld
Biogeosciences, 20, 2283–2299, https://doi.org/10.5194/bg-20-2283-2023, https://doi.org/10.5194/bg-20-2283-2023, 2023
Short summary
Short summary
We propose a new method to quantify carbon cycle feedbacks under negative CO2 emissions. Our method isolates the lagged carbon cycle response to preceding positive emissions from the response to negative emissions. Our findings suggest that feedback parameters calculated with the novel approach are larger than those calculated with the conventional approach whereby carbon cycle inertia is not corrected for, with implications for the effectiveness of carbon dioxide removal in reducing CO2 levels.
Marcus Breil, Annabell Weber, and Joaquim G. Pinto
Biogeosciences, 20, 2237–2250, https://doi.org/10.5194/bg-20-2237-2023, https://doi.org/10.5194/bg-20-2237-2023, 2023
Short summary
Short summary
A promising strategy for mitigating burdens of heat extremes in Europe is to replace dark coniferous forests with brighter deciduous forests. The consequence of this would be reduced absorption of solar radiation, which should reduce the intensities of heat periods. In this study, we show that deciduous forests have a certain cooling effect on heat period intensities in Europe. However, the magnitude of the temperature reduction is quite small.
Gesche Blume-Werry, Jonatan Klaminder, Eveline J. Krab, and Sylvain Monteux
Biogeosciences, 20, 1979–1990, https://doi.org/10.5194/bg-20-1979-2023, https://doi.org/10.5194/bg-20-1979-2023, 2023
Short summary
Short summary
Northern soils store a lot of carbon. Most research has focused on how this carbon storage is regulated by cold temperatures. However, it is soil organisms, from minute bacteria to large earthworms, that decompose the organic material. Novel soil organisms from further south could increase decomposition rates more than climate change does and lead to carbon losses. We therefore advocate for including soil organisms when predicting the fate of soil functions in warming northern ecosystems.
Koramanghat Unnikrishnan Jayakrishnan and Govindasamy Bala
Biogeosciences, 20, 1863–1877, https://doi.org/10.5194/bg-20-1863-2023, https://doi.org/10.5194/bg-20-1863-2023, 2023
Short summary
Short summary
Afforestation and reducing fossil fuel emissions are two important mitigation strategies to reduce the amount of global warming. Our work shows that reducing fossil fuel emissions is relatively more effective than afforestation for the same amount of carbon removed from the atmosphere. However, understanding of the processes that govern the biophysical effects of afforestation should be improved before considering our results for climate policy.
Jens Hartmann, Niels Suitner, Carl Lim, Julieta Schneider, Laura Marín-Samper, Javier Arístegui, Phil Renforth, Jan Taucher, and Ulf Riebesell
Biogeosciences, 20, 781–802, https://doi.org/10.5194/bg-20-781-2023, https://doi.org/10.5194/bg-20-781-2023, 2023
Short summary
Short summary
CO2 can be stored in the ocean via increasing alkalinity of ocean water. Alkalinity can be created via dissolution of alkaline materials, like limestone or soda. Presented research studies boundaries for increasing alkalinity in seawater. The best way to increase alkalinity was found using an equilibrated solution, for example as produced from reactors. Adding particles for dissolution into seawater on the other hand produces the risk of losing alkalinity and degassing of CO2 to the atmosphere.
Damian L. Arévalo-Martínez, Amir Haroon, Hermann W. Bange, Ercan Erkul, Marion Jegen, Nils Moosdorf, Jens Schneider von Deimling, Christian Berndt, Michael Ernst Böttcher, Jasper Hoffmann, Volker Liebetrau, Ulf Mallast, Gudrun Massmann, Aaron Micallef, Holly A. Michael, Hendrik Paasche, Wolfgang Rabbel, Isaac Santos, Jan Scholten, Katrin Schwalenberg, Beata Szymczycha, Ariel T. Thomas, Joonas J. Virtasalo, Hannelore Waska, and Bradley A. Weymer
Biogeosciences, 20, 647–662, https://doi.org/10.5194/bg-20-647-2023, https://doi.org/10.5194/bg-20-647-2023, 2023
Short summary
Short summary
Groundwater flows at the land–ocean transition and the extent of freshened groundwater below the seafloor are increasingly relevant in marine sciences, both because they are a highly uncertain term of biogeochemical budgets and due to the emerging interest in the latter as a resource. Here, we discuss our perspectives on future research directions to better understand land–ocean connectivity through groundwater and its potential responses to natural and human-induced environmental changes.
Morgan Sparey, Peter Cox, and Mark S. Williamson
Biogeosciences, 20, 451–488, https://doi.org/10.5194/bg-20-451-2023, https://doi.org/10.5194/bg-20-451-2023, 2023
Short summary
Short summary
Accurate climate models are vital for mitigating climate change; however, projections often disagree. Using Köppen–Geiger bioclimate classifications we show that CMIP6 climate models agree well on the fraction of global land surface that will change classification per degree of global warming. We find that 13 % of land will change climate per degree of warming from 1 to 3 K; thus, stabilising warming at 1.5 rather than 2 K would save over 7.5 million square kilometres from bioclimatic change.
Huanhuan Wang, Chao Yue, and Sebastiaan Luyssaert
Biogeosciences, 20, 75–92, https://doi.org/10.5194/bg-20-75-2023, https://doi.org/10.5194/bg-20-75-2023, 2023
Short summary
Short summary
This study provided a synthesis of three influential methods to quantify afforestation impact on surface temperature. Results showed that actual effect following afforestation was highly dependent on afforestation fraction. When full afforestation is assumed, the actual effect approaches the potential effect. We provided evidence the afforestation faction is a key factor in reconciling different methods and emphasized that it should be considered for surface cooling impacts in policy evaluation.
Ryan S. Padrón, Lukas Gudmundsson, Laibao Liu, Vincent Humphrey, and Sonia I. Seneviratne
Biogeosciences, 19, 5435–5448, https://doi.org/10.5194/bg-19-5435-2022, https://doi.org/10.5194/bg-19-5435-2022, 2022
Short summary
Short summary
The answer to how much carbon land ecosystems are projected to remove from the atmosphere until 2100 is different for each Earth system model. We find that differences across models are primarily explained by the annual land carbon sink dependence on temperature and soil moisture, followed by the dependence on CO2 air concentration, and by average climate conditions. Our insights on why each model projects a relatively high or low land carbon sink can help to reduce the underlying uncertainty.
Julian Gutt, Stefanie Arndt, David Keith Alan Barnes, Horst Bornemann, Thomas Brey, Olaf Eisen, Hauke Flores, Huw Griffiths, Christian Haas, Stefan Hain, Tore Hattermann, Christoph Held, Mario Hoppema, Enrique Isla, Markus Janout, Céline Le Bohec, Heike Link, Felix Christopher Mark, Sebastien Moreau, Scarlett Trimborn, Ilse van Opzeeland, Hans-Otto Pörtner, Fokje Schaafsma, Katharina Teschke, Sandra Tippenhauer, Anton Van de Putte, Mia Wege, Daniel Zitterbart, and Dieter Piepenburg
Biogeosciences, 19, 5313–5342, https://doi.org/10.5194/bg-19-5313-2022, https://doi.org/10.5194/bg-19-5313-2022, 2022
Short summary
Short summary
Long-term ecological observations are key to assess, understand and predict impacts of environmental change on biotas. We present a multidisciplinary framework for such largely lacking investigations in the East Antarctic Southern Ocean, combined with case studies, experimental and modelling work. As climate change is still minor here but is projected to start soon, the timely implementation of this framework provides the unique opportunity to document its ecological impacts from the very onset.
Daniel François, Adina Paytan, Olga Maria Oliveira de Araújo, Ricardo Tadeu Lopes, and Cátia Fernandes Barbosa
Biogeosciences, 19, 5269–5285, https://doi.org/10.5194/bg-19-5269-2022, https://doi.org/10.5194/bg-19-5269-2022, 2022
Short summary
Short summary
Our analysis revealed that under the two most conservative acidification projections foraminifera assemblages did not display considerable changes. However, a significant decrease in species richness was observed when pH decreases to 7.7 pH units, indicating adverse effects under high-acidification scenarios. A micro-CT analysis revealed that calcified tests of Archaias angulatus were of lower density in low pH, suggesting no acclimation capacity for this species.
Leander Moesinger, Ruxandra-Maria Zotta, Robin van der Schalie, Tracy Scanlon, Richard de Jeu, and Wouter Dorigo
Biogeosciences, 19, 5107–5123, https://doi.org/10.5194/bg-19-5107-2022, https://doi.org/10.5194/bg-19-5107-2022, 2022
Short summary
Short summary
The standardized vegetation optical depth index (SVODI) can be used to monitor the vegetation condition, such as whether the vegetation is unusually dry or wet. SVODI has global coverage, spans the past 3 decades and is derived from multiple spaceborne passive microwave sensors of that period. SVODI is based on a new probabilistic merging method that allows the merging of normally distributed data even if the data are not gap-free.
Rebecca M. Varney, Sarah E. Chadburn, Eleanor J. Burke, and Peter M. Cox
Biogeosciences, 19, 4671–4704, https://doi.org/10.5194/bg-19-4671-2022, https://doi.org/10.5194/bg-19-4671-2022, 2022
Short summary
Short summary
Soil carbon is the Earth’s largest terrestrial carbon store, and the response to climate change represents one of the key uncertainties in obtaining accurate global carbon budgets required to successfully militate against climate change. The ability of climate models to simulate present-day soil carbon is therefore vital. This study assesses soil carbon simulation in the latest ensemble of models which allows key areas for future model development to be identified.
Laurent Bopp, Olivier Aumont, Lester Kwiatkowski, Corentin Clerc, Léonard Dupont, Christian Ethé, Thomas Gorgues, Roland Séférian, and Alessandro Tagliabue
Biogeosciences, 19, 4267–4285, https://doi.org/10.5194/bg-19-4267-2022, https://doi.org/10.5194/bg-19-4267-2022, 2022
Short summary
Short summary
The impact of anthropogenic climate change on the biological production of phytoplankton in the ocean is a cause for concern because its evolution could affect the response of marine ecosystems to climate change. Here, we identify biological N fixation and its response to future climate change as a key process in shaping the future evolution of marine phytoplankton production. Our results show that further study of how this nitrogen fixation responds to environmental change is essential.
Negar Vakilifard, Richard G. Williams, Philip B. Holden, Katherine Turner, Neil R. Edwards, and David J. Beerling
Biogeosciences, 19, 4249–4265, https://doi.org/10.5194/bg-19-4249-2022, https://doi.org/10.5194/bg-19-4249-2022, 2022
Short summary
Short summary
To remain within the Paris climate agreement, there is an increasing need to develop and implement carbon capture and sequestration techniques. The global climate benefits of implementing negative emission technologies over the next century are assessed using an Earth system model covering a wide range of plausible climate states. In some model realisations, there is continued warming after emissions cease. This continued warming is avoided if negative emissions are incorporated.
Marco Reale, Gianpiero Cossarini, Paolo Lazzari, Tomas Lovato, Giorgio Bolzon, Simona Masina, Cosimo Solidoro, and Stefano Salon
Biogeosciences, 19, 4035–4065, https://doi.org/10.5194/bg-19-4035-2022, https://doi.org/10.5194/bg-19-4035-2022, 2022
Short summary
Short summary
Future projections under the RCP8.5 and RCP4.5 emission scenarios of the Mediterranean Sea biogeochemistry at the end of the 21st century show different levels of decline in nutrients, oxygen and biomasses and an acidification of the water column. The signal intensity is stronger under RCP8.5 and in the eastern Mediterranean. Under RCP4.5, after the second half of the 21st century, biogeochemical variables show a recovery of the values observed at the beginning of the investigated period.
Charly A. Moras, Lennart T. Bach, Tyler Cyronak, Renaud Joannes-Boyau, and Kai G. Schulz
Biogeosciences, 19, 3537–3557, https://doi.org/10.5194/bg-19-3537-2022, https://doi.org/10.5194/bg-19-3537-2022, 2022
Short summary
Short summary
This research presents the first laboratory results of quick and hydrated lime dissolution in natural seawater. These two minerals are of great interest for ocean alkalinity enhancement, a strategy aiming to decrease atmospheric CO2 concentrations. Following the dissolution of these minerals, we identified several hurdles and presented ways to avoid them or completely negate them. Finally, we proceeded to various simulations in today’s oceans to implement the strategy at its highest potential.
Taraka Davies-Barnard, Sönke Zaehle, and Pierre Friedlingstein
Biogeosciences, 19, 3491–3503, https://doi.org/10.5194/bg-19-3491-2022, https://doi.org/10.5194/bg-19-3491-2022, 2022
Short summary
Short summary
Biological nitrogen fixation is the largest natural input of new nitrogen onto land. Earth system models mainly represent global total terrestrial biological nitrogen fixation within observational uncertainties but overestimate tropical fixation. The model range of increase in biological nitrogen fixation in the SSP3-7.0 scenario is 3 % to 87 %. While biological nitrogen fixation is a key source of new nitrogen, its predictive power for net primary productivity in models is limited.
Niel Verbrigghe, Niki I. W. Leblans, Bjarni D. Sigurdsson, Sara Vicca, Chao Fang, Lucia Fuchslueger, Jennifer L. Soong, James T. Weedon, Christopher Poeplau, Cristina Ariza-Carricondo, Michael Bahn, Bertrand Guenet, Per Gundersen, Gunnhildur E. Gunnarsdóttir, Thomas Kätterer, Zhanfeng Liu, Marja Maljanen, Sara Marañón-Jiménez, Kathiravan Meeran, Edda S. Oddsdóttir, Ivika Ostonen, Josep Peñuelas, Andreas Richter, Jordi Sardans, Páll Sigurðsson, Margaret S. Torn, Peter M. Van Bodegom, Erik Verbruggen, Tom W. N. Walker, Håkan Wallander, and Ivan A. Janssens
Biogeosciences, 19, 3381–3393, https://doi.org/10.5194/bg-19-3381-2022, https://doi.org/10.5194/bg-19-3381-2022, 2022
Short summary
Short summary
In subarctic grassland on a geothermal warming gradient, we found large reductions in topsoil carbon stocks, with carbon stocks linearly declining with warming intensity. Most importantly, however, we observed that soil carbon stocks stabilised within 5 years of warming and remained unaffected by warming thereafter, even after > 50 years of warming. Moreover, in contrast to the large topsoil carbon losses, subsoil carbon stocks remained unaffected after > 50 years of soil warming.
Roberto Pilli, Ramdane Alkama, Alessandro Cescatti, Werner A. Kurz, and Giacomo Grassi
Biogeosciences, 19, 3263–3284, https://doi.org/10.5194/bg-19-3263-2022, https://doi.org/10.5194/bg-19-3263-2022, 2022
Short summary
Short summary
To become carbon neutral by 2050, the European Union (EU27) forest C sink should increase to −450 Mt CO2 yr-1. Our study highlights that under current management practices (i.e. excluding any policy scenario) the forest C sink of the EU27 member states and the UK may decrease to about −250 Mt CO2eq yr-1 in 2050. The expected impacts of future climate change, however, add a considerable uncertainty, potentially nearly doubling or halving the sink associated with forest management.
Johnathan Daniel Maxey, Neil David Hartstein, Aazani Mujahid, and Moritz Müller
Biogeosciences, 19, 3131–3150, https://doi.org/10.5194/bg-19-3131-2022, https://doi.org/10.5194/bg-19-3131-2022, 2022
Short summary
Short summary
Deep coastal inlets are important sites for regulating land-based organic pollution before it enters coastal oceans. This study focused on how large climate forces, rainfall, and river flow impact organic loading and oxygen conditions in a coastal inlet in Tasmania. Increases in rainfall were linked to higher organic loading and lower oxygen in basin waters. Finally we observed a significant correlation between the Southern Annular Mode and oxygen concentrations in the system's basin waters.
Guang Gao, Tifeng Wang, Jiazhen Sun, Xin Zhao, Lifang Wang, Xianghui Guo, and Kunshan Gao
Biogeosciences, 19, 2795–2804, https://doi.org/10.5194/bg-19-2795-2022, https://doi.org/10.5194/bg-19-2795-2022, 2022
Short summary
Short summary
After conducting large-scale deck-incubation experiments, we found that seawater acidification (SA) increased primary production (PP) in coastal waters but reduced it in pelagic zones, which is mainly regulated by local pH, light intensity, salinity, and community structure. In future oceans, SA combined with decreased upward transports of nutrients may synergistically reduce PP in pelagic zones.
Joko Sampurno, Valentin Vallaeys, Randy Ardianto, and Emmanuel Hanert
Biogeosciences, 19, 2741–2757, https://doi.org/10.5194/bg-19-2741-2022, https://doi.org/10.5194/bg-19-2741-2022, 2022
Short summary
Short summary
This study is the first assessment to evaluate the interactions between river discharges, tides, and storm surges and how they can drive compound flooding in the Kapuas River delta. We successfully created a realistic hydrodynamic model whose domain covers the land–sea continuum using a wetting–drying algorithm in a data-scarce environment. We then proposed a new method to delineate compound flooding hazard zones along the river channels based on the maximum water level profiles.
Svenja Dobbert, Roland Pape, and Jörg Löffler
Biogeosciences, 19, 1933–1958, https://doi.org/10.5194/bg-19-1933-2022, https://doi.org/10.5194/bg-19-1933-2022, 2022
Short summary
Short summary
Understanding how vegetation might respond to climate change is especially important in arctic–alpine ecosystems, where major shifts in shrub growth have been observed. We studied how such changes come to pass and how future changes might look by measuring hourly variations in the stem diameter of dwarf shrubs from one common species. From these data, we are able to discern information about growth mechanisms and can thus show the complexity of shrub growth and micro-environment relations.
Jody Daniel, Rebecca C. Rooney, and Derek T. Robinson
Biogeosciences, 19, 1547–1570, https://doi.org/10.5194/bg-19-1547-2022, https://doi.org/10.5194/bg-19-1547-2022, 2022
Short summary
Short summary
The threat posed by climate change to prairie pothole wetlands is well documented, but gaps remain in our ability to make meaningful predictions about how prairie pothole wetlands will respond. We integrate aspects of topography, land cover/land use and climate to model the permanence class of tens of thousands of wetlands at the western edge of the Prairie Pothole Region.
Cited articles
Archer, D. E., Kheshgi, H., and Maier-Reimer, E.: Dynamics of fossil fuel
CO2 neutralization by marine CaCO3, Global Biogeochem. Cy.,
12, 259–276, https://doi.org/10.1029/98GB00744, 1998.
Bates, N., Astor, Y., Church, M. J., Currie, K., Dore, J.,
Gonaález-Dávila, M., Lorenzoni, L., Muller-Karger, F., Olafsson, J.,
and Santana-Casiano, J. M.: A time-series view of changing ocean chemistry
due to ocean uptake of anthropogenic CO2 and ocean acidification,
Oceanography, 27, 126–141, https://doi.org/10.5670/oceanog.2014.16, 2014.
Bates, R. G.: pH measurements in the marine environment, Pure Appl. Chem.,
54, 229–232, https://doi.org/10.1351/pac198254010229, 1982.
Bates, R. G. and Guggenheim, E. A.: Report on the standardization of pH and
related terminology, Pure Appl. Chem., 1, 163–168,
https://doi.org/10.1351/pac196001010163, 1960.
Baucke, F. G. K.: New IUPAC recommendations on the measurement of pH – background
and essentials, Anal. Bioanal. Chem., 374, 772–777,
https://doi.org/10.1007/s00216-002-1523-4, 2002.
Bopp, L., Resplandy, L., Orr, J. C., Doney, S. C., Dunne, J. P., Gehlen, M., Halloran, P., Heinze, C., Ilyina, T., Séférian, R., Tjiputra, J., and Vichi, M.: Multiple stressors of ocean ecosystems in the 21st century: projections with CMIP5 models, Biogeosciences, 10, 6225–6245, https://doi.org/10.5194/bg-10-6225-2013, 2013.
Boudreau, B. P., Middelburg, J. J., and Luo, Y.: The role of calcification in
carbonate compensation, Nat. Geosci., 11, 894–900,
https://doi.org/10.1038/s41561-018-0259-5, 2018.
Boyd, P. W., Cornwall, C. E., Davison, A., Doney, S. C., Fourquez, M., Hurd,
C. L., Lima, I. D., and McMinn, A.: Biological responses to environmental
heterogeneity under future ocean conditions, Global Change Biol., 22, 2633–2650, https://doi.org/10.1111/gcb.13287, 2016.
Brewer, P. G.: A short history of ocean acidification science in the 20th century: a chemist's view, Biogeosciences, 10, 7411–7422, https://doi.org/10.5194/bg-10-7411-2013, 2013.
Buck, R. P., Rondinini, S., Covington, A. K., Baucke, F. G. K., Brett, C. M.
A., Camoes, M. F., Milton, M. J. T., Mussini, T., Naumann, R., Pratt, K. W.,
Spitzer, P., and Wilson, G. S.: Measurement of pH, Definition, standards, and
procedures (IUPAC Recommendations 2002), Pure Appl. Chem., 74,
2169–2200, https://doi.org/10.1351/pac200274112169, 2002.
Bushinsky, S. M., Takeshita, Y., and Williams, N. L.: Observing changes in
ocean carbonate chemistry: our autonomous future,
Curr. Clim. Change Reports, 5, 207–220, https://doi.org/10.1007/s40641-019-00129-8, 2019.
Caldeira, K. and Wickett, M. E.: Anthropogenic carbon and ocean pH, Nature,
425, 365, https://doi.org/10.1038/425365a, 2003.
Carstensen, J. and Duarte, C. M.: Drivers of pH Variability in Coastal
Ecosystems, Environ. Sci. Technol., 53, 4020–4029,
https://doi.org/10.1021/acs.est.8b03655, 2019.
Carter, B. R., Feely, R. A., Wanninkhof, R., Kouketsu, S., Sonnerup, R. E.,
Pardo, P. C., Sabine, C. L., Johnson, G. C., Sloyan, B. M., Murata, A.,
Mecking, S., Tilbrook, B., Speer, K., Talley, L. D., Millero, F. J.,
Wijffels, S. E., Macdonald, A. M., Gruber, N., and Bullister, J. L.: Pacific
anthropogenic carbon between 1991 and 2017, Global Biogeochem. Cy., 33, 597–617,
https://doi.org/10.1029/2018GB006154, 2019.
Chen, C.-T. A., Lui, H.-K., Hsieh, C.-H., Yanagi, T., Kosugi, N., Ishii, M.,
and Gong, G.-C.: Deep oceans may acidify faster than anticipated due to
global warming, Nat. Clim. Change, 7, 890–894,
https://doi.org/10.1038/s41558-017-0003-y, 2017.
Chu, S. N., Wang, Z. A., Doney, S. C., Lawson, G. L., and Hoering, K. A.:
Changes in anthropogenic carbon storage in the Northeast Pacific in the last
decade, J. Geophys. Res.-Oceans, 121, 4618–4632,
https://doi.org/10.1002/2016JC011775, 2016.
Clark, W. M.: The determination of hydrogen ions, edn. 2, Williams and
Wilkins Company, Baltimore, Maryland, USA, 480 pp., 1922.
Clark, W. M., Wherry, E. T., and Adams, E. Q.: Reply to Wherry and Adams'
article on methods of stating acidity,
J. Washingt. Acad. Sci., 11, 199–202, available at: https://www.jstor.org/stable/24532479 (last access: 1 February 2021), 1921.
Cohen, E. R., Cvitas, T., Frey, J. G., Holström, B., Kuchitsu, K., Marquardt, R., Mills, I., Pavese, F., Quack, M., Stohner, J., Strauss, H. L., Takami, M., and Thor, A. J.: Quantities, Units and Symbols in Physical Chemistry, Third Edit., edited by: Cohen, E. R., Cvitas, T., Frey, J. G., Holström, B., Kuchitsu, K., Marquardt, R., Mills, I., Pavese, F., Quack, M., Stohner, J., Strauss, H. L., Takami, M., and Thor, A. J., Royal Society of Chemistry, Cambridge, 1–250, 2007.
Covington, A. K., Bates, R. G., and Durst, R. A.: Definition of pH scales,
standard reference values, measurement of pH and related terminology
(recommendations 1984), available at:
http://publications.iupac.org/pac/1985/pdf/5703x0531.pdf (last access: 15 January 2021), 1985.
Dickson, A. G.: pH scales and proton-transfer reactions in saline media such
as sea water, Geochim. Cosmochim. Ac., 48, 2299–2308,
https://doi.org/10.1016/0016-7037(84)90225-4, 1984.
Dickson, A. G.: Standard potential of the reaction: AgCl(s) +
H2(g) = Ag(s) + HCl(aq), and the standard acidity constant of
the ion HSO in synthetic sea water from 273.15 to 318.15 K,
J. Chem. Thermodyn., 22, 113–127, https://doi.org/10.1016/0021-9614(90)90074-Z, 1990.
Dickson, A. G.: Seawater carbonate chemistry, Part I, in: Guide to best
practices for ocean acidification research and data reporting, edited by:
Riebesell, U., Fabry, V. J., Hansson, L., and Gattuso, J. P., European Commission, Brussels, Belgium, 17–40, 2010.
Dickson, A. G., Camões, M. F., Spitzer, P., Fisicaro, P., Stoica, D.,
Pawlowicz, R., and Feistel, R.: Metrological challenges for measurements of
key climatological observables, Part 3: seawater pH, Metrologia, 53,
R26–R39, https://doi.org/10.1088/0026-1394/53/1/R26, 2016.
Doney, S. C., Fabry, V. J., Feely, R. A., and Kleypas, J. A.: Ocean
acidification: the other CO2 problem, Annu. Rev. Mar. Sci., 1,
169–192, https://doi.org/10.1146/annurev.marine.010908.163834, 2009.
Doney, S. C., Bopp, L., and Long, M.: Historical and future trends in ocean
climate and biogeochemistry, Oceanography, 27, 108–119,
https://doi.org/10.5670/oceanog.2014.14, 2014.
Dore, J., Lukas, R., Sadler, D. W., Church, M. J., and Karl, D. M.: Physical
and biogeochemical modulation of ocean acidification in the central North
Pacific, P. Natl. Acad. Sci. USA, 106, 12235–12240, https://doi.org/10.1073/pnas.0906044106, 2009.
Dunne, J. P., John, J. G., Adcroft, A. J., Griffies, S. M., Hallberg, R. W.,
Shevliakova, E., Stouffer, R. J., Cooke, W., Dunne, K. A., Harrison, M. J.,
Krasting, J. P., Malyshev, S. L., Milly, P. C. D., Phillipps, P. J.,
Sentman, L. T., Samuels, B. L., Spelman, M. J., Winton, M., Wittenberg, A.
T., and Zadeh, N.: GFDL's ESM2 global coupled climate–carbon Earth System
Models, Part I: physical formulation and baseline simulation
characteristics, J. Climate, 25, 6646–6665,
https://doi.org/10.1175/JCLI-D-11-00560.1, 2012.
Dunne, J. P., John, J. G., Shevliakova, E., Stouffer, R. J., Krasting, J.
P., Malyshev, S. L., Milly, P. C. D., Sentman, L. T., Adcroft, A. J., Cooke,
W., Dunne, K. A., Griffies, S. M., Hallberg, R. W., Harrison, M. J., Levy,
H., Wittenberg, A. T., Phillips, P. J., and Zadeh, N.: GFDL's ESM2 global
coupled climate–carbon Earth System Models, Part II: carbon system
formulation and baseline simulation characteristics, J. Climate, 26,
2247–2267, https://doi.org/10.1175/JCLI-D-12-00150.1, 2013.
Fassbender, A. J., Sabine, C. L., and Palevsky, H. I.: Nonuniform ocean
acidification and attenuation of the ocean carbon sink, Geophys. Res. Lett.,
44, 8404–8413, https://doi.org/10.1002/2017GL074389, 2017.
GCOS: The Global Observing System for climate: implementation needs,
available at: https://library.wmo.int/doc_num.php?explnum_id=3417 (last access: 23 September 2020), 2016.
GOOS: Essential Ocean Variables, available at:
http://www.goosocean.org/index.php?option=com_content&view=article&id=14&Itemid=114, last access: 1 August 2019.
Hales, B., Suhrbier, A., Waldbusser, G. G., Feely, R. A., and Newton, J. A.:
The Carbonate Chemistry of the “Fattening Line”, Willapa Bay, 2011–2014,
Estuar. Coast., 40, 173–186, https://doi.org/10.1007/s12237-016-0136-7, 2017.
Hamer, W. J. and Acree, S. F.: Primary pH measurements and standards,
J. Res. Natl. Bur. Stand., 23, 647–657, 1939.
Hofmann, G. E., Barry, J. P., Edmunds, P. J., Gates, R. D., Hutchins, D. A.,
Klinger, T., and Sewell, M. A.: The effect of ocean acidification on
calcifying organisms in marine ecosystems: an organism-to-ecosystem
perspective, Annu. Rev. Ecol. Evol. S., 41, 127–147,
https://doi.org/10.1146/annurev.ecolsys.110308.120227, 2010.
Hofmann, G. E., Smith, J. E., Johnson, K. S., Send, U., Levin, L. A.,
Micheli, F., Paytan, A., Price, N. N., Peterson, B., Takeshita, Y., Matson,
P. G., Crook, E. D., Kroeker, K. J., Gambi, M. C., Rivest, E. B., Frieder,
C. A., Yu, P. C., and Martz, T. R.: High-frequency dynamics of ocean pH: a
multi-ecosystem comparison, PLoS One, 6, e28983,
https://doi.org/10.1371/journal.pone.0028983, 2011.
Jiang, L.-Q., Carter, B. R., Feely, R. A., Lauvset, S. K., and Olsen, A.:
Surface ocean pH and buffer capacity: past, present and future, Sci. Rep.,
9, 18624, https://doi.org/10.1038/s41598-019-55039-4, 2019.
Kapsenberg, L. and Cyronak, T.: Ocean acidification refugia in variable
environments, Global Change Biol., 25, 3201–3214, https://doi.org/10.1111/gcb.14730,
2019.
Kleypas, J. A., Feely, R. A., Fabry, V. J., Langdon, C., Sabine, C. L., and
Robbins, L. L.: Impacts of ocean acidification on coral reefs and other marine
calcifiers: a guide for future research, report of a workshop held 18–20 April 2005, St. Petersburg, FL, sponsored by NSF, NOAA, and the U.S. Geological Survey, 88 pp., 2006.
Kwiatkowski, L. and Orr, J. C.: Diverging seasonal extremes for ocean
acidification during the twenty-first century, Nat. Clim. Change, 8,
141–145, https://doi.org/10.1038/s41558-017-0054-0, 2018.
Kwiatkowski, L., Torres, O., Bopp, L., Aumont, O., Chamberlain, M., Christian, J. R., Dunne, J. P., Gehlen, M., Ilyina, T., John, J. G., Lenton, A., Li, H., Lovenduski, N. S., Orr, J. C., Palmieri, J., Santana-Falcón, Y., Schwinger, J., Séférian, R., Stock, C. A., Tagliabue, A., Takano, Y., Tjiputra, J., Toyama, K., Tsujino, H., Watanabe, M., Yamamoto, A., Yool, A., and Ziehn, T.: Twenty-first century ocean warming, acidification, deoxygenation, and upper-ocean nutrient and primary production decline from CMIP6 model projections, Biogeosciences, 17, 3439–3470, https://doi.org/10.5194/bg-17-3439-2020, 2020.
Lauvset, S. K., Gruber, N., Landschützer, P., Olsen, A., and Tjiputra, J.: Trends and drivers in global surface ocean pH over the past 3 decades, Biogeosciences, 12, 1285–1298, https://doi.org/10.5194/bg-12-1285-2015, 2015.
Lauvset, S. K., Key, R. M., Olsen, A., van Heuven, S., Velo, A., Lin, X., Schirnick, C., Kozyr, A., Tanhua, T., Hoppema, M., Jutterström, S., Steinfeldt, R., Jeansson, E., Ishii, M., Perez, F. F., Suzuki, T., and Watelet, S.: A new global interior ocean mapped climatology: the 1∘ × 1∘ GLODAP version 2, Earth Syst. Sci. Data, 8, 325–340, https://doi.org/10.5194/essd-8-325-2016, 2016.
Lauvset, S. K., Carter, B. R., Pèrez, F. F., Jiang, L.-Q., Feely, R.
A., Velo, A., and Olsen, A.: Processes driving global interior ocean pH
distribution, Global Biogeochem. Cy., 34, 1–17,
https://doi.org/10.1029/2019GB006229, 2020.
Lewis, E. and Wallace, D. W. R.: Program developed for CO2 system
calculations, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, Tennessee, USA, 4735,
available at:
https://www.nodc.noaa.gov/ocads/oceans/CO2SYS/co2rprt.html (last access: 2 July 2014), 1998.
Lueker, T. J., Dickson, A. G., and Keeling, C. D.: Ocean pCO2 calculated from dissolved inorganic carbon, alkalinity, and equations for K1 and
K2: validation based on laboratory measurements of CO2 in gas and
seawater at equilibrium, Mar. Chem., 70, 105–119,
https://doi.org/10.1016/S0304-4203(00)00022-0, 2000.
Marion, G. M., Millero, F. J., Camões, M. F., Spitzer, P., Feistel, R.,
and Chen, C.-T. A.: pH of seawater, Mar. Chem., 126, 89–96,
https://doi.org/10.1016/j.marchem.2011.04.002, 2011.
McGlashan, M. L.: Manual of symbols and terminology for physicochemical
quantities and units, Pure Appl. Chem., 21, 1–38, 1970.
McNeil, B. I. and Sasse, T. P.: Future ocean hypercapnia driven by
anthropogenic amplification of the natural CO2 cycle, Nature,
529, 383–386, https://doi.org/10.1038/nature16156, 2016.
Millero, F. J.: The marine inorganic carbon cycle, Chem. Rev., 107,
308–341, https://doi.org/10.1021/cr0503557, 2007.
Munro, D. R., Lovenduski, N. S., Takahashi, T., Stephens, B. B., Newberger,
T., and Sweeney, C.: Recent evidence for a strengthening CO2 sink in the
Southern Ocean from carbonate system measurements in the Drake Passage
(2002–2015), Geophys. Res. Lett., 42, 7623–7630,
https://doi.org/10.1002/2015GL065194, 2015.
Orr, J. C., Fabry, V. J., Aumont, O., Bopp, L., Doney, S. C., Feely, R. A.,
Gnanadesikan, A., Gruber, N., Ishida, A., Joos, F., Key, R. M., Lindsay, K.,
Maier-Reimer, E., Matear, R., Monfray, P., Mouchet, A., Najjar, R. G.,
Plattner, G.-K., Rodgers, K. B., Sabine, C. L., Sarmiento, J. L., Schlitzer,
R., Slater, R. D., Totterdell, I. J., Weirig, M.-F., Yamanaka, Y., and Yool,
A.: Anthropogenic ocean acidification over the twenty-first century and its
impact on calcifying organisms, Nature, 437, 681–686,
https://doi.org/10.1038/nature04095, 2005.
Orr, J. C., Epitalon, J.-M., and Gattuso, J.-P.: Comparison of ten packages that compute ocean carbonate chemistry, Biogeosciences, 12, 1483–1510, https://doi.org/10.5194/bg-12-1483-2015, 2015.
Passow, U. and Carlson, C. A.: The biological pump in a high CO2 world,
Mar. Ecol. Prog. Ser., 470, 249–271, https://doi.org/10.3354/meps09985, 2012.
Resplandy, L., Bopp, L., Orr, J. C., and Dunne, J. P.: Role of mode and
intermediate waters in future ocean acidification: Analysis of CMIP5 models,
Geophys. Res. Lett., 40, 3091–3095, https://doi.org/10.1002/grl.50414, 2013.
Revelle, R. and Suess, H. E.: Carbon dioxide exchange between atmosphere and
ocean and the question of an increase of atmospheric CO2 during the
past decades, Tellus, 9, 18–27, https://doi.org/10.1111/j.2153-3490.1957.tb01849.x,
1957.
Rhein, M., Rintoul, S. R., Aoki, S., Campos, E., Chambers, D., Feely, R. A., Gulev, S., Johnson, G. C., Josey, S. A., Kostianoy, A., Mauritzen, C., Roemmich, D., Talley, L. D., and Wang, F.: Observations: Ocean. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2013.
Riahi, K., Rao, S., Krey, V., Cho, C., Chirkov, V., Fischer, G., Kindermann,
G., Nakicenovic, N., and Rafaj, P.: RCP 8.5 – A scenario of comparatively
high greenhouse gas emissions, Climatic Change, 109, 33–57,
https://doi.org/10.1007/s10584-011-0149-y, 2011.
Ríos, A. F., Resplandy, L., García-Ibáñez, M. I., Fajar,
N. M., Velo, A., Padín, X. A., Wanninkhof, R., Steinfeldt, R.,
Rosón, G., Pérez, F. F., and Morel, F. M. M.: Decadal acidification
in the water masses of the Atlantic Ocean, P. Natl. Acad. Sci. USA,
112, 9950–9955, https://doi.org/10.1073/pnas.1504613112, 2015.
Sørensen, S. P. L.: Enzymstudien II: Über die Messung und Bedeutung
der Wasserstoffionen-konzentration bei biologischen Prozessen,
Biochem. Z., 21, 131–200, https://doi.org/10.1007/BF02325444, 1909.
Sørensen, S. P. L. and Linderstrøm-Lang, K.: On the determination and value
of po in electrometric measurements of hydrogen ion concentrations, Compt. rend. trav. lab. Carlsberg, 15, 1–40, 1924.
Spitzer, P. and Pratt, K. W.: The history and development of a rigorous
metrological basis for pH measurements, J. Solid State Electr., 15,
69–76, https://doi.org/10.1007/s10008-010-1106-9, 2011.
Steinacher, M., Joos, F., Frölicher, T. L., Plattner, G.-K., and Doney, S. C.: Imminent ocean acidification in the Arctic projected with the NCAR global coupled carbon cycle-climate model, Biogeosciences, 6, 515–533, https://doi.org/10.5194/bg-6-515-2009, 2009.
Sutton, A. J., Feely, R. A., Sabine, C. L., McPhaden, M. J., Takahashi, T.,
Chavez, F. P., Friederich, G. E., and Mathis, J. T.: Natural variability and
anthropogenic change in equatorial Pacific surface ocean pCO2 and pH,
Global Biogeochem. Cy., 28, 131–145, https://doi.org/10.1002/2013GB004679, 2014.
Takahashi, T., Sutherland, S. C., Chipman, D. W., Goddard, J. G., and Ho, C.:
Climatological distributions of pH, pCO2, total CO2, alkalinity,
and CaCO3 saturation in the global surface ocean, and temporal changes
at selected locations, Mar. Chem., 164, 95–125,
https://doi.org/10.1016/j.marchem.2014.06.004, 2014.
Thyng, K., Greene, C., Hetland, R., Zimmerle, H., and DiMarco, S.: True
Colors of Oceanography: Guidelines for Effective and Accurate Colormap
Selection, Oceanography, 29, 9–13, https://doi.org/10.5670/oceanog.2016.66, 2016.
Uppström, L. R.: The boron-chlorinity ratio of deep seawater from the
Pacific Ocean, Deep. Res. Part I, 21, 161–162, 1974.
van Heuven, S. M. A. C., Pierrot, D., Rae, J. W. B., Lewis, E., and Wallace,
D. W. R.: MATLAB program developed for CO2 system calculations,
ORNL/CDIAC-105b, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, US Department of Energy, Oak Ridge, Tennessee, USA, https://www.ncei.noaa.gov/access/ocean-carbon-data-system/oceans/CO2SYS/co2rprt.html, 2011.
Waters, J. F. and Millero, F. J.: The free proton concentration scale for
seawater pH, Mar. Chem., 149, 8–22, https://doi.org/10.1016/j.marchem.2012.11.003,
2013.
IPCC: Annex I: Glossary, edited by: Weyer, N. M., in: IPCC Special Report on the Ocean and Cryosphere in a Changing Climate, edited by: Pörtner, H.-O., Roberts, D. C., Masson-Delmotte, V., Zhai, P., Tignor, M., Poloczanska, E., Mintenbeck, K., Alegría, A., Nicolai, M., Okem, A., Petzold, J., Rama, B., and Weyer N. M., in press, 2019.
Wherry, E. T.: The statement of acidity and alkalinity, with special
reference to soils, J. Washingt. Acad. Sci., 9, 305–309, available at: https://www.jstor.org/stable/24521412 (last access: 23 September 2020), 1919.
Wherry, E. T. and Adams, E. Q.: Methods of stating acidity, J. Washingt.
Acad. Sci., 11, 197–199, available at:
https://www.jstor.org/stable/24532477 (last access: 23 September 2020), 1921.
Williams, N. L., Feely, R. A., Sabine, C. L., Dickson, A. G., Swift, J. H.,
Talley, L. D., and Russell, J. L.: Quantifying anthropogenic carbon inventory
changes in the Pacific sector of the Southern Ocean, Mar. Chem., 174,
147–160, https://doi.org/10.1016/j.marchem.2015.06.015, 2015.
Woosley, R. J., Millero, F. J., and Wanninkhof, R.: Rapid anthropogenic
changes in CO2 and pH in the Atlantic Ocean: 2003–2014, Global Biogeochem. Cy., 30, 70–90, https://doi.org/10.1002/2015GB005248, 2016.
Short summary
A decline in upper-ocean pH with time is typically ascribed to ocean acidification. A more quantitative interpretation is often confused by failing to recognize the implications of pH being a logarithmic transform of hydrogen ion concentration rather than an absolute measure. This can lead to an unwitting misinterpretation of pH data. We provide three real-world examples illustrating this and recommend the reporting of both hydrogen ion concentration and pH in studies of ocean chemical change.
A decline in upper-ocean pH with time is typically ascribed to ocean acidification. A more...
Altmetrics
Final-revised paper
Preprint