Articles | Volume 16, issue 3
https://doi.org/10.5194/bg-16-797-2019
© Author(s) 2019. 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-16-797-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
13 Feb 2019
Research article |
| 13 Feb 2019
| 13 Feb 2019
Variations in the summer oceanic pCO2 and carbon sink in Prydz Bay using the self-organizing map analysis approach
Suqing Xu
Key Laboratory of Global Change and Marine-Atmospheric Chemistry, Third
Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005,
P. R.
China
Keyhong Park
CORRESPONDING AUTHOR
Division of Polar Ocean Sciences, Korea Polar Research Institute, Incheon
21990, South Korea
Yanmin Wang
Haikou Marine Environment Monitoring Central Station, State Oceanic
Administration, Haikou 570100, China
Liqi Chen
CORRESPONDING AUTHOR
Key Laboratory of Global Change and Marine-Atmospheric Chemistry, Third
Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005,
P. R.
China
Di Qi
Key Laboratory of Global Change and Marine-Atmospheric Chemistry, Third
Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005,
P. R.
China
Bingrui Li
Polar Oceanography Division, Polar Research Institute of China, Shanghai 200136, China
Related authors
Jun Shi, Jinpei Yan, Shanshan Wang, Shuhui Zhao, Miming Zhang, Suqing Xu, Qi Lin, Hang Yang, and Siying Dai
Atmos. Chem. Phys., 23, 10349–10359, https://doi.org/10.5194/acp-23-10349-2023, https://doi.org/10.5194/acp-23-10349-2023, 2023
Short summary
Short summary
An underway aerosol-monitoring system was used to determine the Na+ concentration during different cyclone periods in the Southern Ocean in order to assess the potential effects of cyclones on sea spray aerosol (SSA) emissions. It was estimated that more than 23 % of SSAs were transported upwards during cyclone periods. Vertically transported SSAs can be regarded as an important source of CCN and hence have an effect on climate in the middle and high latitudes of the Southern Hemisphere.
Miming Zhang, Jinpei Yan, Qi Lin, Hongguo Zheng, Keyhong Park, Shuhui Zhao, Suqing Xu, Meina Ruan, Shanshan Wang, Xinlin Zhong, and Suli Zhao
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-454, https://doi.org/10.5194/acp-2022-454, 2022
Revised manuscript not accepted
Short summary
Short summary
Extremely low contribution of DMS chemistry to the aerosols over the high AO was determined by the inhibition of marine phytoplankton, which extends the knowledge how will biogenic sulfur cycle impact the regional climate as AO sea ice retreat in the future.
Jinpei Yan, Jinyoung Jung, Miming Zhang, Federico Bianchi, Yee Jun Tham, Suqing Xu, Qi Lin, Shuhui Zhao, Lei Li, and Liqi Chen
Atmos. Chem. Phys., 20, 3259–3271, https://doi.org/10.5194/acp-20-3259-2020, https://doi.org/10.5194/acp-20-3259-2020, 2020
Short summary
Short summary
Methanesulfonic acid (MSA) is important to the CCN in the MBL. The uptake of MSA on particles is lacking in knowledge. The characteristics of MSA uptake on different particles were studied in the Southern Ocean. The MSA uptake on different particles was associated with particle properties. Uptake of MSA on sea salt particles was favored, while acidic and hydrophobic particles suppressed the MSA uptake. The results extend the knowledge of MSA formation and behavior in the atmosphere.
Dorothee C. E. Bakker, Benjamin Pfeil, Camilla S. Landa, Nicolas Metzl, Kevin M. O'Brien, Are Olsen, Karl Smith, Cathy Cosca, Sumiko Harasawa, Stephen D. Jones, Shin-ichiro Nakaoka, Yukihiro Nojiri, Ute Schuster, Tobias Steinhoff, Colm Sweeney, Taro Takahashi, Bronte Tilbrook, Chisato Wada, Rik Wanninkhof, Simone R. Alin, Carlos F. Balestrini, Leticia Barbero, Nicholas R. Bates, Alejandro A. Bianchi, Frédéric Bonou, Jacqueline Boutin, Yann Bozec, Eugene F. Burger, Wei-Jun Cai, Robert D. Castle, Liqi Chen, Melissa Chierici, Kim Currie, Wiley Evans, Charles Featherstone, Richard A. Feely, Agneta Fransson, Catherine Goyet, Naomi Greenwood, Luke Gregor, Steven Hankin, Nick J. Hardman-Mountford, Jérôme Harlay, Judith Hauck, Mario Hoppema, Matthew P. Humphreys, Christopher W. Hunt, Betty Huss, J. Severino P. Ibánhez, Truls Johannessen, Ralph Keeling, Vassilis Kitidis, Arne Körtzinger, Alex Kozyr, Evangelia Krasakopoulou, Akira Kuwata, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Claire Lo Monaco, Ansley Manke, Jeremy T. Mathis, Liliane Merlivat, Frank J. Millero, Pedro M. S. Monteiro, David R. Munro, Akihiko Murata, Timothy Newberger, Abdirahman M. Omar, Tsuneo Ono, Kristina Paterson, David Pearce, Denis Pierrot, Lisa L. Robbins, Shu Saito, Joe Salisbury, Reiner Schlitzer, Bernd Schneider, Roland Schweitzer, Rainer Sieger, Ingunn Skjelvan, Kevin F. Sullivan, Stewart C. Sutherland, Adrienne J. Sutton, Kazuaki Tadokoro, Maciej Telszewski, Matthias Tuma, Steven M. A. C. van Heuven, Doug Vandemark, Brian Ward, Andrew J. Watson, and Suqing Xu
Earth Syst. Sci. Data, 8, 383–413, https://doi.org/10.5194/essd-8-383-2016, https://doi.org/10.5194/essd-8-383-2016, 2016
Short summary
Short summary
Version 3 of the Surface Ocean CO2 Atlas (www.socat.info) has 14.5 million CO2 (carbon dioxide) values for the years 1957 to 2014 covering the global oceans and coastal seas. Version 3 is an update to version 2 with a longer record and 44 % more CO2 values. The CO2 measurements have been made on ships, fixed moorings and drifting buoys. SOCAT enables quantification of the ocean carbon sink and ocean acidification, as well as model evaluation, thus informing climate negotiations.
Jiao Xue, Tian Zhang, Keyhong Park, Jinpei Yan, Young Jun Yoon, Jiyeon Park, and Bingbing Wang
Atmos. Chem. Phys., 24, 7731–7754, https://doi.org/10.5194/acp-24-7731-2024, https://doi.org/10.5194/acp-24-7731-2024, 2024
Short summary
Short summary
Ice formation by particles is an important way of making mixed-phase and ice clouds. We found that particles collected in the marine atmosphere exhibit diverse ice nucleation abilities and mixing states. Sea salt mixed-sulfate particles were enriched in ice-nucleating particles. Selective aging on sea salt particles made particle populations more externally mixed. Characterizations of particles and their mixing state are needed for a better understanding of aerosol–cloud interactions.
Miao Yu, Peng Lu, Matti Leppäranta, Bin Cheng, Ruibo Lei, Bingrui Li, Qingkai Wang, and Zhijun Li
The Cryosphere, 18, 273–288, https://doi.org/10.5194/tc-18-273-2024, https://doi.org/10.5194/tc-18-273-2024, 2024
Short summary
Short summary
Variations in Arctic sea ice are related not only to its macroscale properties but also to its microstructure. Arctic ice cores in the summers of 2008 to 2016 were used to analyze variations in the ice inherent optical properties related to changes in the ice microstructure. The results reveal changing ice microstructure greatly increased the amount of solar radiation transmitted to the upper ocean even when a constant ice thickness was assumed, especially in marginal ice zones.
Jun Shi, Jinpei Yan, Shanshan Wang, Shuhui Zhao, Miming Zhang, Suqing Xu, Qi Lin, Hang Yang, and Siying Dai
Atmos. Chem. Phys., 23, 10349–10359, https://doi.org/10.5194/acp-23-10349-2023, https://doi.org/10.5194/acp-23-10349-2023, 2023
Short summary
Short summary
An underway aerosol-monitoring system was used to determine the Na+ concentration during different cyclone periods in the Southern Ocean in order to assess the potential effects of cyclones on sea spray aerosol (SSA) emissions. It was estimated that more than 23 % of SSAs were transported upwards during cyclone periods. Vertically transported SSAs can be regarded as an important source of CCN and hence have an effect on climate in the middle and high latitudes of the Southern Hemisphere.
Na Li, Ruibo Lei, Petra Heil, Bin Cheng, Minghu Ding, Zhongxiang Tian, and Bingrui Li
The Cryosphere, 17, 917–937, https://doi.org/10.5194/tc-17-917-2023, https://doi.org/10.5194/tc-17-917-2023, 2023
Short summary
Short summary
The observed annual maximum landfast ice (LFI) thickness off Zhongshan (Davis) was 1.59±0.17 m (1.64±0.08 m). Larger interannual and local spatial variabilities for the seasonality of LFI were identified at Zhongshan, with the dominant influencing factors of air temperature anomaly, snow atop, local topography and wind regime, and oceanic heat flux. The variability of LFI properties across the study domain prevailed at interannual timescales, over any trend during the recent decades.
Miming Zhang, Jinpei Yan, Qi Lin, Hongguo Zheng, Keyhong Park, Shuhui Zhao, Suqing Xu, Meina Ruan, Shanshan Wang, Xinlin Zhong, and Suli Zhao
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-454, https://doi.org/10.5194/acp-2022-454, 2022
Revised manuscript not accepted
Short summary
Short summary
Extremely low contribution of DMS chemistry to the aerosols over the high AO was determined by the inhibition of marine phytoplankton, which extends the knowledge how will biogenic sulfur cycle impact the regional climate as AO sea ice retreat in the future.
Jinyoung Jung, Sang-Bum Hong, Meilian Chen, Jin Hur, Liping Jiao, Youngju Lee, Keyhong Park, Doshik Hahm, Jung-Ok Choi, Eun Jin Yang, Jisoo Park, Tae-Wan Kim, and SangHoon Lee
Atmos. Chem. Phys., 20, 5405–5424, https://doi.org/10.5194/acp-20-5405-2020, https://doi.org/10.5194/acp-20-5405-2020, 2020
Short summary
Short summary
Characteristics of atmospheric sulfur and organic carbon species in marine aerosols and the environmental factors influencing their distributions were investigated over the Southern Ocean and the Amundsen Sea, Antarctica, during austral summer. The simultaneous measurements of chemical species in aerosols as well as the chemical and biological properties of seawater in the Amundsen Sea allowed for a better understanding of the effect of the ocean ecosystem on marine aerosols.
Jinpei Yan, Jinyoung Jung, Miming Zhang, Federico Bianchi, Yee Jun Tham, Suqing Xu, Qi Lin, Shuhui Zhao, Lei Li, and Liqi Chen
Atmos. Chem. Phys., 20, 3259–3271, https://doi.org/10.5194/acp-20-3259-2020, https://doi.org/10.5194/acp-20-3259-2020, 2020
Short summary
Short summary
Methanesulfonic acid (MSA) is important to the CCN in the MBL. The uptake of MSA on particles is lacking in knowledge. The characteristics of MSA uptake on different particles were studied in the Southern Ocean. The MSA uptake on different particles was associated with particle properties. Uptake of MSA on sea salt particles was favored, while acidic and hydrophobic particles suppressed the MSA uptake. The results extend the knowledge of MSA formation and behavior in the atmosphere.
Dorothee C. E. Bakker, Benjamin Pfeil, Camilla S. Landa, Nicolas Metzl, Kevin M. O'Brien, Are Olsen, Karl Smith, Cathy Cosca, Sumiko Harasawa, Stephen D. Jones, Shin-ichiro Nakaoka, Yukihiro Nojiri, Ute Schuster, Tobias Steinhoff, Colm Sweeney, Taro Takahashi, Bronte Tilbrook, Chisato Wada, Rik Wanninkhof, Simone R. Alin, Carlos F. Balestrini, Leticia Barbero, Nicholas R. Bates, Alejandro A. Bianchi, Frédéric Bonou, Jacqueline Boutin, Yann Bozec, Eugene F. Burger, Wei-Jun Cai, Robert D. Castle, Liqi Chen, Melissa Chierici, Kim Currie, Wiley Evans, Charles Featherstone, Richard A. Feely, Agneta Fransson, Catherine Goyet, Naomi Greenwood, Luke Gregor, Steven Hankin, Nick J. Hardman-Mountford, Jérôme Harlay, Judith Hauck, Mario Hoppema, Matthew P. Humphreys, Christopher W. Hunt, Betty Huss, J. Severino P. Ibánhez, Truls Johannessen, Ralph Keeling, Vassilis Kitidis, Arne Körtzinger, Alex Kozyr, Evangelia Krasakopoulou, Akira Kuwata, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Claire Lo Monaco, Ansley Manke, Jeremy T. Mathis, Liliane Merlivat, Frank J. Millero, Pedro M. S. Monteiro, David R. Munro, Akihiko Murata, Timothy Newberger, Abdirahman M. Omar, Tsuneo Ono, Kristina Paterson, David Pearce, Denis Pierrot, Lisa L. Robbins, Shu Saito, Joe Salisbury, Reiner Schlitzer, Bernd Schneider, Roland Schweitzer, Rainer Sieger, Ingunn Skjelvan, Kevin F. Sullivan, Stewart C. Sutherland, Adrienne J. Sutton, Kazuaki Tadokoro, Maciej Telszewski, Matthias Tuma, Steven M. A. C. van Heuven, Doug Vandemark, Brian Ward, Andrew J. Watson, and Suqing Xu
Earth Syst. Sci. Data, 8, 383–413, https://doi.org/10.5194/essd-8-383-2016, https://doi.org/10.5194/essd-8-383-2016, 2016
Short summary
Short summary
Version 3 of the Surface Ocean CO2 Atlas (www.socat.info) has 14.5 million CO2 (carbon dioxide) values for the years 1957 to 2014 covering the global oceans and coastal seas. Version 3 is an update to version 2 with a longer record and 44 % more CO2 values. The CO2 measurements have been made on ships, fixed moorings and drifting buoys. SOCAT enables quantification of the ocean carbon sink and ocean acidification, as well as model evaluation, thus informing climate negotiations.
Related subject area
Biogeochemistry: Greenhouse Gases
Nitrous oxide (N2O) in Macquarie Harbour, Tasmania
Technical note: A low-cost, automatic soil–plant–atmosphere enclosure system to investigate CO2 and evapotranspiration flux dynamics
Tidal influence on carbon dioxide and methane fluxes from tree stems and soils in mangrove forests
Drought conditions disrupt atmospheric carbon uptake in a Mediterranean saline lake
Physicochemical perturbation increases nitrous oxide production from denitrification in soils and sediments
Carbon degradation and mobilisation potentials of thawing permafrost peatlands in northern Norway inferred from laboratory incubations
Seasonal dynamics and regional distribution patterns of CO2 and CH4 in the north-eastern Baltic Sea
Interannual and seasonal variability of the air–sea CO2 exchange at Utö in the coastal region of the Baltic Sea
CO2 emissions of drained coastal peatlands in the Netherlands and potential emission reduction by water infiltration systems
Seasonal and inter-annual variability of carbon fluxes in southern Africa seen by GOSAT
Influence of wind strength and direction on diffusive methane fluxes and atmospheric methane concentrations above the North Sea
Eddy covariance fluxes of CO2, CH4 and N2O on a drained peatland forest after clearcutting
Eddy Covariance Evaluation of Ecosystem Fluxes at a Temperate Saltmarsh in Victoria, Australia Shows Large CO2 Uptake
Using eddy covariance observations to determine the carbon sequestration characteristics of subalpine forests in the Qinghai–Tibet Plateau
Dynamics of CO2 and CH4 fluxes in Red Sea mangrove soils
Isotopomer labeling and oxygen dependence of hybrid nitrous oxide production
The emission of CO from tropical rainforest soils
Interferences caused by the microbial methane cycle during the assessment of abandoned oil and gas wells
Carbon sequestration in different urban vegetation types in Southern Finland
Modelling CO2 and N2O emissions from soils in silvopastoral systems of the West African Sahelian band
Ensemble estimates of global wetland methane emissions over 2000–2020
A case study on topsoil removal and rewetting for paludiculture: effect on biogeochemistry and greenhouse gas emissions from Typha latifolia, Typha angustifolia, and Azolla filiculoides
Seasonal carbon fluxes from vegetation and soil in a Mediterranean non-tidal salt marsh
Assessing improvements in global ocean pCO2 machine learning reconstructions with Southern Ocean autonomous sampling
Proglacial methane emissions driven by meltwater and groundwater flushing in a high Arctic glacial catchment
Timescale dependence of airborne fraction and underlying climate–carbon-cycle feedbacks for weak perturbations in CMIP5 models
Technical note: Preventing CO2 overestimation from mercuric or copper(II) chloride preservation of dissolved greenhouse gases in freshwater samples
Exploring temporal and spatial variation of nitrous oxide flux using several years of peatland forest automatic chamber data
Diurnal versus spatial variability of greenhouse gas emissions from an anthropogenically modified lowland river in Germany
Regional assessment and uncertainty analysis of carbon and nitrogen balances at cropland scale using the ecosystem model LandscapeDNDC
Resolving heterogeneous fluxes from tundra halves the growing season carbon budget
Lawns and meadows in urban green space – a comparison from perspectives of greenhouse gases, drought resilience and plant functional types
Large contribution of soil N2O emission to the global warming potential of a large-scale oil palm plantation despite changing from conventional to reduced management practices
Air temperature and precipitation constraining the modelled wetland methane emissions in a boreal region in Northern Europe
Identifying landscape hot and cold spots of soil greenhouse gas fluxes by combining field measurements and remote sensing data
Explainable machine learning for modelling of net ecosystem exchange in boreal forest
Enhanced Southern Ocean CO2 outgassing as a result of stronger and poleward shifted southern hemispheric westerlies
Spatial and temporal variability of methane emissions and environmental conditions in a hyper-eutrophic fishpond
Optical and radar Earth observation data for upscaling methane emissions linked to permafrost degradation in sub-Arctic peatlands in northern Sweden
Herbivore–shrub interactions influence ecosystem respiration and biogenic volatile organic compound composition in the subarctic
Methane emissions due to reservoir flushing: a significant emission pathway?
Carbon dioxide and methane fluxes from mounds of African fungus-growing termites
Diel and seasonal methane dynamics in the shallow and turbulent Wadden Sea
Technical note: Skirt chamber – an open dynamic method for the rapid and minimally intrusive measurement of greenhouse gas emissions from peatlands
Seasonal variability of nitrous oxide concentrations and emissions in a temperate estuary
Reviews and syntheses: Recent advances in microwave remote sensing in support of terrestrial carbon cycle science in Arctic–boreal regions
Simulated methane emissions from Arctic ponds are highly sensitive to warming
Water-table-driven greenhouse gas emission estimates guide peatland restoration at national scale
Relationships between greenhouse gas production and landscape position during short-term permafrost thaw under anaerobic conditions in the Lena Delta
Carbon emissions and radiative forcings from tundra wildfires in the Yukon–Kuskokwim River Delta, Alaska
Johnathan Daniel Maxey, Neil D. Hartstein, Hermann W. Bange, and Moritz Müller
Biogeosciences, 21, 5613–5637, https://doi.org/10.5194/bg-21-5613-2024, https://doi.org/10.5194/bg-21-5613-2024, 2024
Short summary
Short summary
The distribution of N2O in fjord-like estuaries is poorly described in the Southern Hemisphere. Our study describes N2O distribution and its drivers in one such system in Macquarie Harbour, Tasmania. Water samples were collected seasonally in 2022 and 2023. Results show the system removes atmospheric N2O when river flow is high, whereas the system emits N2O when the river flow is low. N2O generated in basins is intercepted by the surface water and exported to the ocean during high river flow.
Wael Al Hamwi, Maren Dubbert, Jörg Schaller, Matthias Lück, Marten Schmidt, and Mathias Hoffmann
Biogeosciences, 21, 5639–5651, https://doi.org/10.5194/bg-21-5639-2024, https://doi.org/10.5194/bg-21-5639-2024, 2024
Short summary
Short summary
We present a fully automatic, low-cost soil–plant enclosure system to monitor CO2 and evapotranspiration fluxes within greenhouse experiments. It operates in two modes: independent, using low-cost sensors, and dependent, where multiple chambers connect to a single gas analyzer via a low-cost multiplexer. This system provides precise, accurate measurements and high temporal resolution, enabling comprehensive monitoring of plant–soil responses to various treatments and conditions.
Zhao-Jun Yong, Wei-Jen Lin, Chiao-Wen Lin, and Hsing-Juh Lin
Biogeosciences, 21, 5247–5260, https://doi.org/10.5194/bg-21-5247-2024, https://doi.org/10.5194/bg-21-5247-2024, 2024
Short summary
Short summary
We measured CO2 and CH4 fluxes from mangrove stems and soils of Avicennia marina and Kandelia obovata during tidal cycles. Both stem types served as CO2 and CH4 sources, emitting less CH4 than soils, with no difference in CO2 flux. While A. marina stems showed increased CO2 fluxes from low to high tides, they acted as a CH4 sink before flooding and as a source after ebbing. However, K. obovata stems showed no flux pattern. This study highlights the need to consider tidal influence and species.
Ihab Alfadhel, Ignacio Peralta-Maraver, Isabel Reche, Enrique P. Sánchez-Cañete, Sergio Aranda-Barranco, Eva Rodríguez-Velasco, Andrew S. Kowalski, and Penélope Serrano-Ortiz
Biogeosciences, 21, 5117–5129, https://doi.org/10.5194/bg-21-5117-2024, https://doi.org/10.5194/bg-21-5117-2024, 2024
Short summary
Short summary
Inland saline lakes are crucial in the global carbon cycle, but increased droughts may alter their carbon exchange capacity. We measured CO2 and CH4 fluxes in a Mediterranean saline lake using the eddy covariance method under dry and wet conditions. We found the lake acts as a carbon sink during wet periods but not during droughts. These results highlight the importance of saline lakes in carbon sequestration and their vulnerability to climate-change-induced droughts.
Nathaniel B. Weston, Cynthia Troy, Patrick J. Kearns, Jennifer L. Bowen, William Porubsky, Christelle Hyacinthe, Christof Meile, Philippe Van Cappellen, and Samantha B. Joye
Biogeosciences, 21, 4837–4851, https://doi.org/10.5194/bg-21-4837-2024, https://doi.org/10.5194/bg-21-4837-2024, 2024
Short summary
Short summary
Nitrous oxide (N2O) is a potent greenhouse and ozone-depleting gas produced largely from microbial nitrogen cycling processes, and human activities have resulted in increases in atmospheric N2O. We investigate the role of physical and chemical disturbances to soils and sediments in N2O production. We demonstrate that physicochemical perturbation increases N2O production, microbial community adapts over time, and initial perturbation appears to confer resilience to subsequent disturbance.
Sigrid Trier Kjær, Sebastian Westermann, Nora Nedkvitne, and Peter Dörsch
Biogeosciences, 21, 4723–4737, https://doi.org/10.5194/bg-21-4723-2024, https://doi.org/10.5194/bg-21-4723-2024, 2024
Short summary
Short summary
Permafrost peatlands are thawing due to climate change, releasing large quantities of carbon that degrades upon thawing and is released as CO2, CH4 or dissolved organic carbon (DOC). We incubated thawed Norwegian permafrost peat plateaus and thermokarst pond sediment found next to permafrost for up to 350 d to measure carbon loss. CO2 production was initially the highest, whereas CH4 production increased over time. The largest carbon loss was measured at the top of the peat plateau core as DOC.
Silvie Lainela, Erik Jacobs, Stella-Theresa Luik, Gregor Rehder, and Urmas Lips
Biogeosciences, 21, 4495–4519, https://doi.org/10.5194/bg-21-4495-2024, https://doi.org/10.5194/bg-21-4495-2024, 2024
Short summary
Short summary
We evaluate the variability of carbon dioxide and methane in the surface layer of the north-eastern basins of the Baltic Sea in 2018. We show that the shallower coastal areas have considerably higher spatial variability and seasonal amplitude of surface layer pCO2 and cCH4 than measured in the offshore areas of the Baltic Sea. Despite this high variability, caused mostly by coastal physical processes, the average annual air–sea CO2 fluxes differed only marginally between the sub-basins.
Martti Honkanen, Mika Aurela, Juha Hatakka, Lumi Haraguchi, Sami Kielosto, Timo Mäkelä, Jukka Seppälä, Simo-Matti Siiriä, Ken Stenbäck, Juha-Pekka Tuovinen, Pasi Ylöstalo, and Lauri Laakso
Biogeosciences, 21, 4341–4359, https://doi.org/10.5194/bg-21-4341-2024, https://doi.org/10.5194/bg-21-4341-2024, 2024
Short summary
Short summary
The exchange of CO2 between the sea and the atmosphere was studied in the Archipelago Sea, Baltic Sea, in 2017–2021, using an eddy covariance technique. The sea acted as a net source of CO2 with an average yearly emission of 27.1 gC m-2 yr-1, indicating that the marine ecosystem respired carbon that originated elsewhere. The yearly CO2 emission varied between 18.2–39.2 gC m-2 yr-1, mostly due to the yearly variation of ecosystem carbon uptake.
Ralf C. H. Aben, Daniël van de Craats, Jim Boonman, Stijn H. Peeters, Bart Vriend, Coline C. F. Boonman, Ype van der Velde, Gilles Erkens, and Merit van den Berg
Biogeosciences, 21, 4099–4118, https://doi.org/10.5194/bg-21-4099-2024, https://doi.org/10.5194/bg-21-4099-2024, 2024
Short summary
Short summary
Drained peatlands cause high CO2 emissions. We assessed the effectiveness of subsurface water infiltration systems (WISs) in reducing CO2 emissions related to increases in water table depth (WTD) on 12 sites for up to 4 years. Results show WISs markedly reduced emissions by 2.1 t CO2-C ha-1 yr-1. The relationship between the amount of carbon above the WTD and CO2 emission was stronger than the relationship between WTD and emission. Long-term monitoring is crucial for accurate emission estimates.
Eva-Marie Metz, Sanam Noreen Vardag, Sourish Basu, Martin Jung, and André Butz
EGUsphere, https://doi.org/10.5194/egusphere-2024-1955, https://doi.org/10.5194/egusphere-2024-1955, 2024
Short summary
Short summary
We estimate CO2 fluxes in semi-arid southern Africa from 2009 to 2018 based on satellite CO2 measurements and atmospheric inverse modelling. By selecting process-based vegetation models, which agree with the satellite CO2 fluxes, we find that soil respiration mainly drives the seasonality, whereas photosynthesis substantially influences the interannual variability. Our study emphasizes the need of better representing the response of semi-arid ecosystems to soil rewetting in vegetation models.
Ingeborg Bussmann, Eric P. Achterberg, Holger Brix, Nicolas Brüggemann, Götz Flöser, Claudia Schütze, and Philipp Fischer
Biogeosciences, 21, 3819–3838, https://doi.org/10.5194/bg-21-3819-2024, https://doi.org/10.5194/bg-21-3819-2024, 2024
Short summary
Short summary
Methane (CH4) is an important greenhouse gas and contributes to climate warming. However, the input of CH4 from coastal areas to the atmosphere is not well defined. Dissolved and atmospheric CH4 was determined at high spatial resolution in or above the North Sea. The atmospheric CH4 concentration was mainly influenced by wind direction. With our detailed study on the spatial distribution of CH4 fluxes we were able to provide a detailed and more realistic estimation of coastal CH4 fluxes.
Olli-Pekka Tikkasalo, Olli Peltola, Pavel Alekseychik, Juha Heikkinen, Samuli Launiainen, Aleksi Lehtonen, Qian Li, Eduardo Martinez-García, Mikko Peltoniemi, Petri Salovaara, Ville Tuominen, and Raisa Mäkipää
EGUsphere, https://doi.org/10.5194/egusphere-2024-1994, https://doi.org/10.5194/egusphere-2024-1994, 2024
Short summary
Short summary
The emissions of greenhouse gases (GHG) carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) were measured from a clearcut peatland forest site. The measurements covered the whole year of 2022 which was the second growing season after the clearcut. The site was a strong GHG source and the highest emissions came from CO2 followed by N2O and CH4. A statistical model that included information on different surfaces in the site was developed to unravel surface-type specific GHG fluxes.
Ruth Reef, Edoardo Daly, Tivanka Anandappa, Eboni-Jane Vienna-Hallam, Harriet Robertson, Matthew Peck, and Adrien Guyot
EGUsphere, https://doi.org/10.5194/egusphere-2024-2182, https://doi.org/10.5194/egusphere-2024-2182, 2024
Short summary
Short summary
Studies show that saltmarshes excel at capturing carbon from the atmosphere. In this study, we measured CO2 flux in an Australian temperate saltmarsh on French Island. The temperate saltmarsh exhibited strong seasonality. During the warmer growing season, the saltmarsh absorbed on average 10.5 grams of CO2 from the atmosphere per m2 daily. Even in winter, when plants were dormant, it continued to be a CO2 sink, albeit smaller. Cool temperatures and high cloud cover inhibit carbon sequestration.
Niu Zhu, Jinniu Wang, Dongliang Luo, Xufeng Wang, Cheng Shen, and Ning Wu
Biogeosciences, 21, 3509–3522, https://doi.org/10.5194/bg-21-3509-2024, https://doi.org/10.5194/bg-21-3509-2024, 2024
Short summary
Short summary
Our study delves into the vital role of subalpine forests in the Qinghai–Tibet Plateau as carbon sinks in the context of climate change. Utilizing advanced eddy covariance systems, we uncover their significant carbon sequestration potential, observing distinct seasonal patterns influenced by temperature, humidity, and radiation. Notably, these forests exhibit robust carbon absorption, with potential implications for global carbon balance.
Jessica Ashley Valerie Breavington, Alexandra Steckbauer, Chuancheng Fu, Mongi Ennasri, and Carlos Manuel Duarte
EGUsphere, https://doi.org/10.5194/egusphere-2024-1831, https://doi.org/10.5194/egusphere-2024-1831, 2024
Short summary
Short summary
Mangroves are known for storing large amounts of carbon in their soils, but this is lower in the Red Sea due to challenging growth conditions. We collected soil cores over multiple seasons to measure soil properties, and the greenhouse gasses (GHG) of carbon dioxide and methane. We found that GHG emissions are generally a small offset to carbon storage but punctuated by periods of very high GHG emission and this variability is linked to multiple environmental and soil properties.
Colette L. Kelly, Nicole M. Travis, Pascale Anabelle Baya, Claudia Frey, Xin Sun, Bess B. Ward, and Karen L. Casciotti
Biogeosciences, 21, 3215–3238, https://doi.org/10.5194/bg-21-3215-2024, https://doi.org/10.5194/bg-21-3215-2024, 2024
Short summary
Short summary
Nitrous oxide, a potent greenhouse gas, accumulates in regions of the ocean that are low in dissolved oxygen. We used a novel combination of chemical tracers to determine how nitrous oxide is produced in one of these regions, the eastern tropical North Pacific Ocean. Our experiments showed that the two most important sources of nitrous oxide under low-oxygen conditions are denitrification, an anaerobic process, and a novel “hybrid” process performed by ammonia-oxidizing archaea.
Hella van Asperen, Thorsten Warneke, Alessandro Carioca de Araújo, Bruce Forsberg, Sávio José Filgueiras Ferreira, Thomas Röckmann, Carina van der Veen, Sipko Bulthuis, Leonardo Ramos de Oliveira, Thiago de Lima Xavier, Jailson da Mata, Marta de Oliveira Sá, Paulo Ricardo Teixeira, Julie Andrews de França e Silva, Susan Trumbore, and Justus Notholt
Biogeosciences, 21, 3183–3199, https://doi.org/10.5194/bg-21-3183-2024, https://doi.org/10.5194/bg-21-3183-2024, 2024
Short summary
Short summary
Carbon monoxide (CO) is regarded as an important indirect greenhouse gas. Soils can emit and take up CO, but, until now, uncertainty remains as to which process dominates in tropical rainforests. We present the first soil CO flux measurements from a tropical rainforest. Based on our observations, we report that tropical rainforest soils are a net source of CO. In addition, we show that valley streams and inundated areas are likely additional hot spots of CO in the ecosystem.
Sebastian F. A. Jordan, Stefan Schloemer, Martin Krüger, Tanja Heffner, Marcus A. Horn, and Martin Blumenberg
EGUsphere, https://doi.org/10.5194/egusphere-2024-1461, https://doi.org/10.5194/egusphere-2024-1461, 2024
Short summary
Short summary
In a multilayered approach, we studied eight cut and buried abandoned oil wells in a peat rich area of Northern Germany for methane flux, soil gas composition, and isotopic signatures of soil methane and carbon dioxide. The detected methane emissions were of biogenic, peat origin and were not associated with the abandoned wells. Additional microbial analysis and methane oxidation rate measurements demonstrated a high methane-emission mitigation potential in the studied peat-soils.
Laura Thölix, Leif Backman, Minttu Havu, Esko Karvinen, Jesse Soininen, Justine Trémeau, Olli Nevalainen, Joyson Ahongshangbam, Leena Järvi, and Liisa Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2024-1453, https://doi.org/10.5194/egusphere-2024-1453, 2024
Short summary
Short summary
Cities seek carbon neutrality and are interested in the sinks of urban vegetation. Measurements are difficult to do which leads to the need for modeling carbon cycle. In this study, we examined the performance of models in estimating carbon sequestration rates in lawns, park trees, and urban forests in Helsinki, Finland. We found that models simulated seasonal and annual variations well. Trees had larger carbon sequestration rates compared with lawns and irrigation often increased carbon sink.
Yélognissè Agbohessou, Claire Delon, Manuela Grippa, Eric Mougin, Daouda Ngom, Espoir Koudjo Gaglo, Ousmane Ndiaye, Paulo Salgado, and Olivier Roupsard
Biogeosciences, 21, 2811–2837, https://doi.org/10.5194/bg-21-2811-2024, https://doi.org/10.5194/bg-21-2811-2024, 2024
Short summary
Short summary
Emissions of greenhouse gases in the Sahel are not well represented because they are considered weak compared to the rest of the world. However, natural areas in the Sahel emit carbon dioxide and nitrous oxides, which need to be assessed because of extended surfaces. We propose an assessment of such emissions in Sahelian silvopastoral systems and of how they are influenced by environmental characteristics. These results are essential to inform climate change strategies in the region.
Zhen Zhang, Benjamin Poulter, Joe R. Melton, William J. Riley, George H. Allen, David J. Beerling, Philippe Bousquet, Josep G. Canadell, Etienne Fluet-Chouinard, Philippe Ciais, Nicola Gedney, Peter O. Hopcroft, Akihiko Ito, Robert B. Jackson, Atul K. Jain, Katherine Jensen, Fortunat Joos, Thomas Kleinen, Sara Knox, Tingting Li, Xin Li, Xiangyu Liu, Kyle McDonald, Gavin McNicol, Paul A. Miller, Jurek Müller, Prabir K. Patra, Changhui Peng, Shushi Peng, Zhangcai Qin, Ryan M. Riggs, Marielle Saunois, Qing Sun, Hanqin Tian, Xiaoming Xu, Yuanzhi Yao, Xi Yi, Wenxin Zhang, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
EGUsphere, https://doi.org/10.5194/egusphere-2024-1584, https://doi.org/10.5194/egusphere-2024-1584, 2024
Short summary
Short summary
This study assesses global methane emissions from wetlands between 2000 and 2020 using multiple models. We found that wetland emissions increased by 6–7 Tg CH4 per year in the 2010s compared to the 2000s. Rising temperatures primarily drove this increase, while changes in precipitation and CO2 levels also played roles. Our findings highlight the importance of wetlands in the global methane budget and the need for continuous monitoring to understand their impact on climate change.
Merit van den Berg, Thomas M. Gremmen, Renske J. E. Vroom, Jacobus van Huissteden, Jim Boonman, Corine J. A. van Huissteden, Ype van der Velde, Alfons J. P. Smolders, and Bas P. van de Riet
Biogeosciences, 21, 2669–2690, https://doi.org/10.5194/bg-21-2669-2024, https://doi.org/10.5194/bg-21-2669-2024, 2024
Short summary
Short summary
Drained peatlands emit 3 % of the global greenhouse gas emissions. Paludiculture is a way to reduce CO2 emissions while at the same time generating an income for landowners. The side effect is the potentially high methane emissions. We found very high methane emissions for broadleaf cattail compared with narrowleaf cattail and water fern. The rewetting was, however, effective to stop CO2 emissions for all species. The highest potential to reduce greenhouse gas emissions had narrowleaf cattail.
Lorena Carrasco-Barea, Dolors Verdaguer, Maria Gispert, Xavier D. Quintana, Hélène Bourhis, and Laura Llorens
EGUsphere, https://doi.org/10.5194/egusphere-2024-1320, https://doi.org/10.5194/egusphere-2024-1320, 2024
Short summary
Short summary
Carbon dioxide fluxes have been measured seasonally in four plant species in a Mediterranean non-tidal salt marsh highlighting the high carbon removal potential that these species have. Carbon dioxide and methane emissions from soil showed high variability among the habitats studied and they were generally higher than those observed in tidal salt marshes. Our results are important to make more accurate predictions regarding carbon emissions from these ecosystems.
Thea H. Heimdal, Galen A. McKinley, Adrienne J. Sutton, Amanda R. Fay, and Lucas Gloege
Biogeosciences, 21, 2159–2176, https://doi.org/10.5194/bg-21-2159-2024, https://doi.org/10.5194/bg-21-2159-2024, 2024
Short summary
Short summary
Measurements of ocean carbon are limited in time and space. Machine learning algorithms are therefore used to reconstruct ocean carbon where observations do not exist. Improving these reconstructions is important in order to accurately estimate how much carbon the ocean absorbs from the atmosphere. In this study, we find that a small addition of observations from the Southern Ocean, obtained by autonomous sampling platforms, could significantly improve the reconstructions.
Gabrielle Emma Kleber, Leonard Magerl, Alexandra V. Turchyn, Mark Trimmer, Yizhu Zhu, and Andrew Hodson
EGUsphere, https://doi.org/10.5194/egusphere-2024-1273, https://doi.org/10.5194/egusphere-2024-1273, 2024
Short summary
Short summary
Our research on Svalbard has uncovered that melting glaciers can release large amounts of methane, a potent greenhouse gas. By studying a glacier over two summers, we found that its river was highly concentrated in methane. This suggests that as the Arctic warms and glaciers melt, they could be a significant source of methane emissions. This is the first time such emissions have been measured on Svalbard, indicating a wider environmental concern as similar processes may occur across the Arctic.
Guilherme L. Torres Mendonça, Julia Pongratz, and Christian H. Reick
Biogeosciences, 21, 1923–1960, https://doi.org/10.5194/bg-21-1923-2024, https://doi.org/10.5194/bg-21-1923-2024, 2024
Short summary
Short summary
We study the timescale dependence of airborne fraction and underlying feedbacks by a theory of the climate–carbon system. Using simulations we show the predictive power of this theory and find that (1) this fraction generally decreases for increasing timescales and (2) at all timescales the total feedback is negative and the model spread in a single feedback causes the spread in the airborne fraction. Our study indicates that those are properties of the system, independently of the scenario.
François Clayer, Jan Erik Thrane, Kuria Ndungu, Andrew King, Peter Dörsch, and Thomas Rohrlack
Biogeosciences, 21, 1903–1921, https://doi.org/10.5194/bg-21-1903-2024, https://doi.org/10.5194/bg-21-1903-2024, 2024
Short summary
Short summary
Determination of dissolved greenhouse gas (GHG) in freshwater allows us to estimate GHG fluxes. Mercuric chloride (HgCl2) is used to preserve water samples prior to GHG analysis despite its environmental and health impacts and interferences with water chemistry in freshwater. Here, we tested the effects of HgCl2, two substitutes and storage time on GHG in water from two boreal lakes. Preservation with HgCl2 caused overestimation of CO2 concentration with consequences for GHG flux estimation.
Helena Rautakoski, Mika Korkiakoski, Jarmo Mäkelä, Markku Koskinen, Kari Minkkinen, Mika Aurela, Paavo Ojanen, and Annalea Lohila
Biogeosciences, 21, 1867–1886, https://doi.org/10.5194/bg-21-1867-2024, https://doi.org/10.5194/bg-21-1867-2024, 2024
Short summary
Short summary
Current and future nitrous oxide (N2O) emissions are difficult to estimate due to their high variability in space and time. Several years of N2O fluxes from drained boreal peatland forest indicate high importance of summer precipitation, winter temperature, and snow conditions in controlling annual N2O emissions. The results indicate increasing year-to-year variation in N2O emissions in changing climate with more extreme seasonal weather conditions.
Matthias Koschorreck, Norbert Kamjunke, Uta Koedel, Michael Rode, Claudia Schuetze, and Ingeborg Bussmann
Biogeosciences, 21, 1613–1628, https://doi.org/10.5194/bg-21-1613-2024, https://doi.org/10.5194/bg-21-1613-2024, 2024
Short summary
Short summary
We measured the emission of carbon dioxide (CO2) and methane (CH4) from different sites at the river Elbe in Germany over 3 days to find out what is more important for quantification: small-scale spatial variability or diurnal temporal variability. We found that CO2 emissions were very different between day and night, while CH4 emissions were more different between sites. Dried out river sediments contributed to CO2 emissions, while the side areas of the river were important CH4 sources.
Odysseas Sifounakis, Edwin Haas, Klaus Butterbach-Bahl, and Maria P. Papadopoulou
Biogeosciences, 21, 1563–1581, https://doi.org/10.5194/bg-21-1563-2024, https://doi.org/10.5194/bg-21-1563-2024, 2024
Short summary
Short summary
We performed a full assessment of the carbon and nitrogen cycles of a cropland ecosystem. An uncertainty analysis and quantification of all carbon and nitrogen fluxes were deployed. The inventory simulations include greenhouse gas emissions of N2O, NH3 volatilization and NO3 leaching from arable land cultivation in Greece. The inventory also reports changes in soil organic carbon and nitrogen stocks in arable soils.
Sarah M. Ludwig, Luke Schiferl, Jacqueline Hung, Susan M. Natali, and Roisin Commane
Biogeosciences, 21, 1301–1321, https://doi.org/10.5194/bg-21-1301-2024, https://doi.org/10.5194/bg-21-1301-2024, 2024
Short summary
Short summary
Landscapes are often assumed to be homogeneous when using eddy covariance fluxes, which can lead to biases when calculating carbon budgets. In this study we report eddy covariance carbon fluxes from heterogeneous tundra. We used the footprints of each flux observation to unmix the fluxes coming from components of the landscape. We identified and quantified hot spots of carbon emissions in the landscape. Accurately scaling with landscape heterogeneity yielded half as much regional carbon uptake.
Justine Trémeau, Beñat Olascoaga, Leif Backman, Esko Karvinen, Henriikka Vekuri, and Liisa Kulmala
Biogeosciences, 21, 949–972, https://doi.org/10.5194/bg-21-949-2024, https://doi.org/10.5194/bg-21-949-2024, 2024
Short summary
Short summary
We studied urban lawns and meadows in the Helsinki metropolitan area, Finland. We found that meadows are more resistant to drought events but that they do not increase carbon sequestration compared with lawns. Moreover, the transformation from lawns to meadows did not demonstrate any negative climate effects in terms of greenhouse gas emissions. Even though social and economic aspects also steer urban development, these results can guide planning to consider carbon-smart options.
Guantao Chen, Edzo Veldkamp, Muhammad Damris, Bambang Irawan, Aiyen Tjoa, and Marife D. Corre
Biogeosciences, 21, 513–529, https://doi.org/10.5194/bg-21-513-2024, https://doi.org/10.5194/bg-21-513-2024, 2024
Short summary
Short summary
We established an oil palm management experiment in a large-scale oil palm plantation in Jambi, Indonesia. We recorded oil palm fruit yield and measured soil CO2, N2O, and CH4 fluxes. After 4 years of treatment, compared with conventional fertilization with herbicide weeding, reduced fertilization with mechanical weeding did not reduce yield and soil greenhouse gas emissions, which highlights the legacy effects of over a decade of conventional management prior to the start of the experiment.
Tuula Aalto, Aki Tsuruta, Jarmo Mäkelä, Jurek Mueller, Maria Tenkanen, Eleanor Burke, Sarah Chadburn, Yao Gao, Vilma Mannisenaho, Thomas Kleinen, Hanna Lee, Antti Leppänen, Tiina Markkanen, Stefano Materia, Paul Miller, Daniele Peano, Olli Peltola, Benjamin Poulter, Maarit Raivonen, Marielle Saunois, David Wårlind, and Sönke Zaehle
EGUsphere, https://doi.org/10.5194/egusphere-2023-2873, https://doi.org/10.5194/egusphere-2023-2873, 2024
Short summary
Short summary
Wetland methane responses to temperature and precipitation were studied in a boreal wetland-rich region in Northern Europe using ecosystem models, atmospheric inversions and up-scaled flux observations. The ecosystem models differed in their responses to temperature and precipitation and in their seasonality. However, multi-model means, inversions and up-scaled fluxes had similar seasonality, and they suggested co-limitation by temperature and precipitation.
Elizabeth Gachibu Wangari, Ricky Mwangada Mwanake, Tobias Houska, David Kraus, Gretchen Maria Gettel, Ralf Kiese, Lutz Breuer, and Klaus Butterbach-Bahl
Biogeosciences, 20, 5029–5067, https://doi.org/10.5194/bg-20-5029-2023, https://doi.org/10.5194/bg-20-5029-2023, 2023
Short summary
Short summary
Agricultural landscapes act as sinks or sources of the greenhouse gases (GHGs) CO2, CH4, or N2O. Various physicochemical and biological processes control the fluxes of these GHGs between ecosystems and the atmosphere. Therefore, fluxes depend on environmental conditions such as soil moisture, soil temperature, or soil parameters, which result in large spatial and temporal variations of GHG fluxes. Here, we describe an example of how this variation may be studied and analyzed.
Ekaterina Ezhova, Topi Laanti, Anna Lintunen, Pasi Kolari, Tuomo Nieminen, Ivan Mammarella, Keijo Heljanko, and Markku Kulmala
EGUsphere, https://doi.org/10.5194/egusphere-2023-2559, https://doi.org/10.5194/egusphere-2023-2559, 2023
Short summary
Short summary
ML models are gaining popularity in biogeosciences. They are applied as gapfilling methods and used to upscale carbon fluxes to larger areas based on local measurements. In this study, we use Explainable ML methods to elucidate performance of machine learning models for carbon dioxide fluxes in boreal forest. We show that statistically equal models treat input variables differently. Explainable ML can help scientists to make informed solutions when applying ML models in their research.
Laurie C. Menviel, Paul Spence, Andrew E. Kiss, Matthew A. Chamberlain, Hakase Hayashida, Matthew H. England, and Darryn Waugh
Biogeosciences, 20, 4413–4431, https://doi.org/10.5194/bg-20-4413-2023, https://doi.org/10.5194/bg-20-4413-2023, 2023
Short summary
Short summary
As the ocean absorbs 25% of the anthropogenic emissions of carbon, it is important to understand the impact of climate change on the flux of carbon between the ocean and the atmosphere. Here, we use a very high-resolution ocean, sea-ice, carbon cycle model to show that the capability of the Southern Ocean to uptake CO2 has decreased over the last 40 years due to a strengthening and poleward shift of the southern hemispheric westerlies. This trend is expected to continue over the coming century.
Petr Znachor, Jiří Nedoma, Vojtech Kolar, and Anna Matoušů
Biogeosciences, 20, 4273–4288, https://doi.org/10.5194/bg-20-4273-2023, https://doi.org/10.5194/bg-20-4273-2023, 2023
Short summary
Short summary
We conducted intensive spatial sampling of the hypertrophic fishpond to better understand the spatial dynamics of methane fluxes and environmental heterogeneity in fishponds. The diffusive fluxes of methane accounted for only a minor fraction of the total fluxes and both varied pronouncedly within the pond and over the studied summer season. This could be explained only by the water depth. Wind substantially affected temperature, oxygen and chlorophyll a distribution in the pond.
Sofie Sjögersten, Martha Ledger, Matthias Siewert, Betsabé de la Barreda-Bautista, Andrew Sowter, David Gee, Giles Foody, and Doreen S. Boyd
Biogeosciences, 20, 4221–4239, https://doi.org/10.5194/bg-20-4221-2023, https://doi.org/10.5194/bg-20-4221-2023, 2023
Short summary
Short summary
Permafrost thaw in Arctic regions is increasing methane emissions, but quantification is difficult given the large and remote areas impacted. We show that UAV data together with satellite data can be used to extrapolate emissions across the wider landscape as well as detect areas at risk of higher emissions. A transition of currently degrading areas to fen type vegetation can increase emission by several orders of magnitude, highlighting the importance of quantifying areas at risk.
Cole G. Brachmann, Tage Vowles, Riikka Rinnan, Mats P. Björkman, Anna Ekberg, and Robert G. Björk
Biogeosciences, 20, 4069–4086, https://doi.org/10.5194/bg-20-4069-2023, https://doi.org/10.5194/bg-20-4069-2023, 2023
Short summary
Short summary
Herbivores change plant communities through grazing, altering the amount of CO2 and plant-specific chemicals (termed VOCs) emitted. We tested this effect by excluding herbivores and studying the CO2 and VOC emissions. Herbivores reduced CO2 emissions from a meadow community and altered VOC composition; however, community type had the strongest effect on the amount of CO2 and VOCs released. Herbivores can mediate greenhouse gas emissions, but the effect is marginal and community dependent.
Ole Lessmann, Jorge Encinas Fernández, Karla Martínez-Cruz, and Frank Peeters
Biogeosciences, 20, 4057–4068, https://doi.org/10.5194/bg-20-4057-2023, https://doi.org/10.5194/bg-20-4057-2023, 2023
Short summary
Short summary
Based on a large dataset of seasonally resolved methane (CH4) pore water concentrations in a reservoir's sediment, we assess the significance of CH4 emissions due to reservoir flushing. In the studied reservoir, CH4 emissions caused by one flushing operation can represent 7 %–14 % of the annual CH4 emissions and depend on the timing of the flushing operation. In reservoirs with high sediment loadings, regular flushing may substantially contribute to the overall CH4 emissions.
Matti Räsänen, Risto Vesala, Petri Rönnholm, Laura Arppe, Petra Manninen, Markus Jylhä, Jouko Rikkinen, Petri Pellikka, and Janne Rinne
Biogeosciences, 20, 4029–4042, https://doi.org/10.5194/bg-20-4029-2023, https://doi.org/10.5194/bg-20-4029-2023, 2023
Short summary
Short summary
Fungus-growing termites recycle large parts of dead plant material in African savannas and are significant sources of greenhouse gases. We measured CO2 and CH4 fluxes from their mounds and surrounding soils in open and closed habitats. The fluxes scale with mound volume. The results show that emissions from mounds of fungus-growing termites are more stable than those from other termites. The soil fluxes around the mound are affected by the termite colonies at up to 2 m distance from the mound.
Tim René de Groot, Anne Margriet Mol, Katherine Mesdag, Pierre Ramond, Rachel Ndhlovu, Julia Catherine Engelmann, Thomas Röckmann, and Helge Niemann
Biogeosciences, 20, 3857–3872, https://doi.org/10.5194/bg-20-3857-2023, https://doi.org/10.5194/bg-20-3857-2023, 2023
Short summary
Short summary
This study investigates methane dynamics in the Wadden Sea. Our measurements revealed distinct variations triggered by seasonality and tidal forcing. The methane budget was higher in warmer seasons but surprisingly high in colder seasons. Methane dynamics were amplified during low tides, flushing the majority of methane into the North Sea or releasing it to the atmosphere. Methanotrophic activity was also elevated during low tide but mitigated only a small fraction of the methane efflux.
Frederic Thalasso, Brenda Riquelme, Andrés Gómez, Roy Mackenzie, Francisco Javier Aguirre, Jorge Hoyos-Santillan, Ricardo Rozzi, and Armando Sepulveda-Jauregui
Biogeosciences, 20, 3737–3749, https://doi.org/10.5194/bg-20-3737-2023, https://doi.org/10.5194/bg-20-3737-2023, 2023
Short summary
Short summary
A robust skirt-chamber design to capture and quantify greenhouse gas emissions from peatlands is presented. Compared to standard methods, this design improves the spatial resolution of field studies in remote locations while minimizing intrusion.
Gesa Schulz, Tina Sanders, Yoana G. Voynova, Hermann W. Bange, and Kirstin Dähnke
Biogeosciences, 20, 3229–3247, https://doi.org/10.5194/bg-20-3229-2023, https://doi.org/10.5194/bg-20-3229-2023, 2023
Short summary
Short summary
Nitrous oxide (N2O) is an important greenhouse gas. However, N2O emissions from estuaries underlie significant uncertainties due to limited data availability and high spatiotemporal variability. We found the Elbe Estuary (Germany) to be a year-round source of N2O, with the highest emissions in winter along with high nitrogen loads. However, in spring and summer, N2O emissions did not decrease alongside lower nitrogen loads because organic matter fueled in situ N2O production along the estuary.
Alex Mavrovic, Oliver Sonnentag, Juha Lemmetyinen, Jennifer L. Baltzer, Christophe Kinnard, and Alexandre Roy
Biogeosciences, 20, 2941–2970, https://doi.org/10.5194/bg-20-2941-2023, https://doi.org/10.5194/bg-20-2941-2023, 2023
Short summary
Short summary
This review supports the integration of microwave spaceborne information into carbon cycle science for Arctic–boreal regions. The microwave data record spans multiple decades with frequent global observations of soil moisture and temperature, surface freeze–thaw cycles, vegetation water storage, snowpack properties, and land cover. This record holds substantial unexploited potential to better understand carbon cycle processes.
Zoé Rehder, Thomas Kleinen, Lars Kutzbach, Victor Stepanenko, Moritz Langer, and Victor Brovkin
Biogeosciences, 20, 2837–2855, https://doi.org/10.5194/bg-20-2837-2023, https://doi.org/10.5194/bg-20-2837-2023, 2023
Short summary
Short summary
We use a new model to investigate how methane emissions from Arctic ponds change with warming. We find that emissions increase substantially. Under annual temperatures 5 °C above present temperatures, pond methane emissions are more than 3 times higher than now. Most of this increase is caused by an increase in plant productivity as plants provide the substrate microbes used to produce methane. We conclude that vegetation changes need to be included in predictions of pond methane emissions.
Julian Koch, Lars Elsgaard, Mogens H. Greve, Steen Gyldenkærne, Cecilie Hermansen, Gregor Levin, Shubiao Wu, and Simon Stisen
Biogeosciences, 20, 2387–2403, https://doi.org/10.5194/bg-20-2387-2023, https://doi.org/10.5194/bg-20-2387-2023, 2023
Short summary
Short summary
Utilizing peatlands for agriculture leads to large emissions of greenhouse gases worldwide. The emissions are triggered by lowering the water table, which is a necessary step in order to make peatlands arable. Many countries aim at reducing their emissions by restoring peatlands, which can be achieved by stopping agricultural activities and thereby raising the water table. We estimate a total emission of 2.6 Mt CO2-eq for organic-rich peatlands in Denmark and a potential reduction of 77 %.
Mélissa Laurent, Matthias Fuchs, Tanja Herbst, Alexandra Runge, Susanne Liebner, and Claire C. Treat
Biogeosciences, 20, 2049–2064, https://doi.org/10.5194/bg-20-2049-2023, https://doi.org/10.5194/bg-20-2049-2023, 2023
Short summary
Short summary
In this study we investigated the effect of different parameters (temperature, landscape position) on the production of greenhouse gases during a 1-year permafrost thaw experiment. For very similar carbon and nitrogen contents, our results show a strong heterogeneity in CH4 production, as well as in microbial abundance. According to our study, these differences are mainly due to the landscape position and the hydrological conditions established as a result of the topography.
Michael Moubarak, Seeta Sistla, Stefano Potter, Susan M. Natali, and Brendan M. Rogers
Biogeosciences, 20, 1537–1557, https://doi.org/10.5194/bg-20-1537-2023, https://doi.org/10.5194/bg-20-1537-2023, 2023
Short summary
Short summary
Tundra wildfires are increasing in frequency and severity with climate change. We show using a combination of field measurements and computational modeling that tundra wildfires result in a positive feedback to climate change by emitting significant amounts of long-lived greenhouse gasses. With these effects, attention to tundra fires is necessary for mitigating climate change.
Cited articles
Bakker, D. C. E., Pfeil, B. Landa, C. S., Metzl, N., O'Brien, K. M., Olsen,
A.,Smith, K., Cosca, C., Harasawa, S., Jones, S. D., Nakaoka, S., Nojiri, Y.,
Schuster, U., Steinhoff, T., Sweeney, C., Takahashi, T., Tilbrook, B., Wada,
C., Wanninkhof, R., Alin, S. R., Balestrini, C. F., Barbero, L., Bates, N.
R., Bianchi, A. A., Bonou, F., Boutin, J., Bozec, Y., Burger, E. F., Cai,
W.-J., Castle, R. D., Chen, L., Chierici, M., Currie, K., Evans, W.,
Featherstone, C., Feely, R. A., Fransson, A., Goyet, C., Greenwood, N.,
Gregor, L., Hankin, S., Hardman-Mountford, N. J., Harlay, J., Hauck, J.,
Hoppema, M., Humphreys, M. P., Hunt, C. W., Huss, B., Ibánhez, J. S. P.,
Johannessen, T., Keeling, R., Kitidis, V., Körtzinger, A., Kozyr, A.,
Krasakopoulou, E., Kuwata, A., Landschützer, P., Lauvset, S. K.,
Lefèvre, N., Lo Monaco, C., Manke, A., Mathis, J. T., Merlivat, L.,
Millero, F. J., Monteiro, P. M. S., Munro, D. R., Murata, A., Newberger, T.,
Omar, A. M., Ono, T., Paterson, K., Pearce, D., Pierrot, D., Robbins, L. L.,
Saito, S., Salisbury, J., Schlitzer, R., Schneider, B., Schweitzer, R.,
Sieger, R., Skjelvan, I., Sullivan, K. F., Sutherland, S. C., Sutton, A. J.,
Tadokoro, K., Telszewski, M., Tuma, M., Van Heuven, S. M. A. C., Vandemark,
D., Ward, B., Watson, A. J., and Xu, S.: A multi-decade record of high
quality fCO2 data in version 3 of the Surface Ocean CO2
Atlas (SOCAT), Earth Syst. Sci. Data, 8, 383–413, https://doi.org/10.5194/essd-8-383-2016, 2016.
Barbini, R., Fantoni, R., Palucci, A., Colao, F., Sandrini, S., Ceradini, S.,
Tositti, L., Tubertini, O., and Ferrari, G. M.: Simultaneous measurements of
remote lidar chlorophyll and surface CO2 distributions in the Ross
Sea, Int. J. Remote Sens., 24, 3807–3819, 2003.
Bates, N. R., Hansell, D. A., Carlson, C. A., and Gordon, L. I.: Distribution
of CO2 species, estimates of net community production, and air-sea
CO2 exchange in the Ross Sea polynya, J. Geophys.
Res., 103, 2883–2896, 1998a.
Bates, N. R., Takahashi, T., Chipman, D. W., and Knapp, A. H.: Variability
of pCO2 on diel to seasonal time scales in the Sargasso Sea,
J.
Geophys. Res., 103, 15567–15585, 1998b.
Brainerd, K. E. and Gregg, M. C.: Surface mixed and mixing layer depth,
Deep-Sea Res. Pt. A, 42, 1521–1543, 1995.
Burkill, P. H., Edwards, E. S., and Sleight, M. A.: Microzooplankton and
their role in controlling phytoplankton growth in the marginal ice zone of
the Bellingshausen Sea, Deep-Sea Res. Pt. II, 42, 1277–1290, 1995.
Chen, L., Xu, S., Gao, Z., Chen, H., Zhang, Y., Zhan, J., and Li, W.:
Estimation of monthly air-sea CO2 flux in the southern Atlantic and
Indian Ocean using in-situ and remotely sensed data, Remote Sens.
Environ., 115, 1935–1941, 2011.
Chierici, M., Olsen, A., Johannessen, T., Trinanes, J., and Wanninkhof, R.:
Algorithms to estimate the carbon dioxide uptake in the northern North
Atlantic using ship-observations, satellite and ocean analysis data,
Deep-Sea Res. Pt. II, 56, 630–639, 2009.
Chu, P. C. and Fan, C.: Optimal linear fitting for objective determination
of ocean mixed layer depth from glider profiles, J. Atmos.
Ocean. Technol., 27, 1893–1989, 2010.
Dandonneau, Y.: Sea-surface partial pressure of carbon dioxide in the
eastern equatorial Pacific (August 1991 to October 1992): A multivariate
analysis of physical and biological factors, Deep-Sea Res. Pt. II, 42,
349–364, 1995.
Dong, S., Sprintall, J., Gille, S. T., and Talley, L.: Southern Ocean
mixed-layer depth from Argo float profiles, J. Geophys. Res.,
113, C06013, https://doi.org/10.1029/2006JC004051, 2008.
Edwards, A. M., Platt, T., and Sathyendranath, S.: The high-nutrient,
low-chlorophyll regime of the ocean: limits on biomass and nitrate before
and after iron enrichment, Ecol. Model., 171, 103–125, 2004.
Friedrich, T. and Oschlies, A.: Neural network-based estimates of North
Atlantic surface pCO2 from satellite data: A
methodological study, J. Geophys. Res., 114, C03020,
https://doi.org/10.1029/2007JC004646, 2009a.
Friedrich, T. and Oschlies, A.: Basin-scale pCO2 maps estimated from
ARGO float data: A model study, J. Geophys. Res., 114, C10012,
https://doi.org/10.1029/2009JC005322, 2009b.
Gao, Z., Chen, L., and Gao, Y.: Air-sea carbon fluxes and there controlling
factors in the PrydzBay in the Antarctic, Acta Oceanol. Sin., 3,
136–146, 2008.
Gibson, P. B., Perkins-Kirkpatrick, S. E., Uotila, P., Pepler, A. S., and
Alexander, L. V.: On the use of self-organizing maps for studying climate
extremes, J. Geophys. Res.-Atmos., 122, 3891–3903,
2017.
Gibsonab, J. A. E. and Trullb, T. W.: Annual cycle of fCO2 under
sea-ice and in open water in Prydz Bay, east Antarctica, Mar. Chem.,
66, 187–200, 1999.
Hales, B., Strutton, P., Saraceno, M., Letelier, R., Takahashi, T., Feely,
R., Sabine, C., and Chavez, F.: Satellite-based prediction of pCO2 in
coastal waters of the eastern North Pacific, Prog. Oceanogr., 103,
1–15, 2012.
Hardman-Mountford, N., Litt, E., Mangi, S., Dye, S., Schuster, U., Bakker,
D., and Watson, A.: Ocean uptake of carbon dioxide (CO2), MCCIP
BriefingNotes, 9 pp., 2009.
Heil, P., Allison, I., and Lytle,V. I.: Seasonal and interannual variations
of the oceanic heat flux under a landfast Antarctic sea ice cover, J.
Geophys. Res., 101, 25741–25752, https://doi.org/10.1029/96JC01921, 1996.
Huang, J., Xu, F., Zhou, K., Xiu, P., and Lin, Y.: Temporal evolution of
near-surface chlorophyll over cyclonic eddy lifecycles in the southeastern
Pacific, J. Geophys. Res.-Ocean., 122, 6165–6179, 2017a.
Huang, W., Chen, R., Yang, Z., Wang, B., and Ma, W.: Exploring the combined
effects of the Arctic Oscillation and ENSO on the wintertime climate over
East Asia using self-organizing maps, J. Geophys. Res.-Atmos., 122, 9107–9129, 2017b.
Iskandar, I.: Seasonal and interannual patterns of sea surface temperature
in Banda Sea as revealed by self-organizing map, Cont. Shelf Res.,
30, 1136–1148, 2010.
Jacobs, S. S. and Georgi, D. T.: Observations on the south-west
Indian/Antarctic Ocean, in: A Voyage of Discovery, edited by: Angel, M., Deep-Sea
Res., 24, 43–84, 1977.
Jamet, C., Moulin, C., and Lefèvre, N.: Estimation of the oceanic
pCO2 in the North Atlantic from VOS lines in-situ
measurements: parameters needed to generate seasonally mean maps, Ann.
Geophys., 25, 2247–2257, https://doi.org/10.5194/angeo-25-2247-2007, 2007.
Jiang, L. Q., Cai, W. J., Wanninkhof, R., Wang, Y., and Lüger, H.:
Air–sea CO2 fluxes on the US South Atlantic Bight: Spatial and
seasonal variability, J. Geophys. Res., 113, C07019,
https://doi.org/10.1029/2007JC004366, 2008.
Jo, Y. H., Dai, M. H., Zhai, W. D., Yan, X. H., and Shang, S. L.: On the
variations of sea surface pCO2 in the northern South China
sea: A remote sensing based neural network approach, J. Geophys. Res., 117,
C08022, https://doi.org/10.1029/2011JC007745, 2012.
Kohonen, T.: Self-Organization and Associative Memory, Springer, Berlin,
1984.
Lafevre, N., Watson, A. J., and Watson, A. R.: A comparison of multiple
regression and neural network techniques for mapping in situ
pCO2 data, Tellus B, 57, 375–384, 2005.
Laruelle, G. G., Landschützer, P., Gruber, N., Tison, J.-L., Delille, B.,
and Regnier, P.: Global high-resolution monthly pCO2
climatology for the coastal ocean derived from neural network interpolation,
Biogeosciences, 14, 4545–4561, https://doi.org/10.5194/bg-14-4545-2017,
2017.
Lei, R., Li, Z., Cheng, B., Zhang, Z., and Heil, P.: Annual cycle of landfast
sea ice in Prydz Bay, East Antarctica, J. Geophys. Res.-Atmos., 115, C02006,
https://doi.org/10.1029/2008JC005223, 2010.
Liu, C., Wang, Z., Cheng, C., Xia, R., Li, B., and Xie, Z.: Modeling modified
circumpolar deep water intrusions onto the Prydz Bay continental shelf, East
Antarctica, J. Geophys. Res., 122, 5198–5217, https://doi.org/10.1002/2016JC012336,
2017.
Liu, Y., Weisberg, R. H., and He, R.: Sea Surface Temperature Patterns on the
West Florida Shelf Using Growing Hierarchical Self-Organizing Maps, J. Atmos.
Ocean. Technol., 23, 325–338, 2006.
Liu, Z. and Cheng, Z.: The distribution feature of size-fractionated
chlorophyll a and primary productivity in Prydz Bay and its north sea area
during the austral summer, Chinese J. Polar Sci., 14, 81–89, 2003.
Liu, Z. L., Ning, X. R., Cai, Y. M., Liu, C. G., and Zhu, G. H.: Primary
productivity and chlorophyll a in the surface water on the route encircling
the Antarctica during austral summer of 1999/2000, Polar Res., 112, 235–244,
2000.
Lüger, H., Wallace, D. W. R., Körtzinger, A., and Nojiri, Y.: The
pCO2 variability in the midlatitude North Atlantic Ocean
during a full annual cycle, Global Biogeochem. Cy., 18, GB3023,
https://doi.org/10.1029/2003GB002200, 2004.
Metzl, N., Brunet, C., Jabaud-Jan, A., Poisson, A., and Schauer, B.: Sumer
and winter air-sea CO2 fluxes in the Southern Ocean, Deep-Sea Res.
Pt. I, 53, 1548–1563, 2006.
Middleton, J. H. and Humphries, S. E.: Thermohaline structure and mixing in
the region of Prydz Bay, Antarctica, Deep-Sea Res. Pt. A, 36, 1255–1266,
1989.
Morrison, J. M., Gaurin, S., Codispoti, L. A., Takahashi, T., Millero, F. J.,
Gardner, W. D., and Richardson, M. J.: Seasonal evolution of hydrographic
properties in the Antarctic circumpolar current at 170 W during 19970–1998,
Deep-Sea Res. Pt. I, 48, 3943–3972, 2001.
Nakaoka, S., Telszewski, M., Nojiri, Y., Yasunaka, S., Miyazaki, C., Mukai,
H., and Usui, N.: Estimating temporal and spatial variation of ocean surface
pCO2 in the North Pacific using a self-organizing map neural
network technique, Biogeosciences, 10, 6093–6106,
https://doi.org/10.5194/bg-10-6093-2013, 2013.
Nunes Vaz, R. A. and Lennon, G. W.: Physical oceanography of the Prydz Bay
region of Antarctic waters, Deep-Sea Res. Pt. I, 43, 603–641, 1996.
Olsen, A., Trinanes, J. A., and Wanninkhof, R.: Sea-air flux of CO2
in the Caribbean Sea estimated using in situ and remote sensing data, Remote
Sens. Environ., 89, 309–325, 2004.
Pfeil, B., Olsen, A., Bakker, D. C. E., Hankin, S., Koyuk, H., Kozyr, A.,
Malczyk, J., Manke, A., Metzl, N., Sabine, C. L., Akl, J., Alin, S. R.,
Bates, N., Bellerby, R. G. J., Borges, A., Boutin, J., Brown, P. J., Cai,
W.-J., Chavez, F. P., Chen, A., Cosca, C., Fassbender, A. J., Feely, R. A.,
González-Dávila, M., Goyet, C., Hales, B., Hardman-Mountford, N.,
Heinze, C., Hood, M., Hoppema, M., Hunt, C. W., Hydes, D., Ishii, M.,
Johannessen, T., Jones, S. D., Key, R. M., Körtzinger, A.,
Landschützer, P., Lauvset, S. K., Lefèvre, N., Lenton, A., Lourantou,
A., Merlivat, L., Midorikawa, T., Mintrop, L., Miyazaki, C., Murata, A.,
Nakadate, A., Nakano, Y., Nakaoka, S., Nojiri, Y., Omar, A. M., Padin, X. A.,
Park, G.-H., Paterson, K., Perez, F. F., Pierrot, D., Poisson, A., Ríos,
A. F., Santana-Casiano, J. M., Salisbury, J., Sarma, V. V. S. S., Schlitzer,
R., Schneider, B., Schuster, U., Sieger, R., Skjelvan, I., Steinhoff, T.,
Suzuki, T., Takahashi, T., Tedesco, K., Telszewski, M., Thomas, H., Tilbrook,
B., Tjiputra, J., Vandemark, D., Veness, T., Wanninkhof, R., Watson, A. J.,
Weiss, R., Wong, C. S., and Yoshikawa-Inoue, H.: A uniform, quality
controlled Surface Ocean CO2 Atlas (SOCAT), Earth Syst. Sci. Data, 5,
125–143, https://doi.org/10.5194/essd-5-125-2013, 2013.
Pierrot, D., Neill, C., Sullivan, L., Castle, R., Wanninkhof, R., Lüger,
H., Johannessen, T., Olsen, A., Feely, R. A., and Cosca, C. E.:
Recommendations for autonomous underway pCO2 measuring
systems and data-reduction routines, Deep-Sea Res. Pt. II, 56, 512–522,
2009.
Rangama, Y., Boutin, J., Etcheto, J., Merlivat, L., Takahashi, T., Delille,
B., Frankignoulle, M., and Bakker, D. C. E.: Variability of the net air-sea
CO2 flux inferred from shipboard and satellite measurements in the
Southern Ocean south of Tasmania and New Zealand, J. Geophys. Res.-Ocean.,
110, 1–17, https://doi.org/10.1029/2004JC002619, 2005.
Roden, N. P., Shadwick, E. H., Tilbrook, B., and Trull, T. W.: Annual cycle
of carbonate chemistry and decadal change in coastal Prydz Bay, East
Antarctica, Mar. Chem., 155, 135–147, 2013.
Rubin, S. I., Takahashi, T., and Goddard, J. G.: Primary productivity and
nutrient utilization ratios in the Pacific sector of the Southern Ocean based
on seasonal changes in seawater chemistry, Deep-Sea Res. Pt. I, 45,
1211–1234, 1998.
Sabine, L., Feely, R. A., Gruber, N., Key, R. M., Lee, K., Bullister, J. L.,
Wanninkhof, R., Wong, S., Wallace, D. W. R., Tilbrook, B., Millero, F. J.,
Peng, T.-H., Kozyr, A., Ono, T., and Rios, A. F.: The oceanic sink for
anthropogenic CO2, Science, 305, 367–371,
https://doi.org/10.1126/science.1097403, 2004.
Sarma, V. V. S. S., Saino, T., Sasaoka, K., Nojiri, Y., Ono, T., Ishii, M.,
Inoue, H. Y., and Matsumoto, K.: Basin-scale pCO2
distribution using satellite sea surface temperature, Chla, and
climatological salinity in the North Pacific in spring and summer, Global
Biogeochem. Cy., 20, GB3005, https://doi.org/10.1029/2005GB002594, 2006.
Shadwick, E. H., Trull, T. W., Thomas, H., and Gibson, J. A. E.:
Vulnerability of polar oceans to anthropogenic acidification: comparison of
Arctic and Antarctic seasonal cycles, Sci. Rep., 3, 2339,
https://doi.org/10.1038/srep02339, 2013.
Silulwane, N. F., Richardson, A. J., Shillington, F. A., and Mitchell-Innes,
B. A.: Identification and classification of vertical chlorophyll patterns in
the Benguela upwelling system and Angola-Benguela front using an artificial
neural network, S. Afr. J. Mar. Sci., 23, 37–51, 2001.
Smith, N. and Tréguer, P.: Physical and chemical oceanography in the
vicinity of Prydz Bay, Antarctica, Cambridge University Press, Cambridge,
1994.
Smith, N. R., Zhaoqian, D., Kerry, K. R., and Wright, S.: Water masses and
circulation in the region of Prydz Bay Antarctica, Deep-Sea Res., 31,
1121–1147, 1984.
Spreen, G., Kaleschke, L., and Heygster, G.: Sea ice remote sensing using
AMSR-E 89 GHz channels, J. Geophys. Res., 113, C02S03,
https://doi.org/10.1029/2005JC003384, 2008.
Sun, W. P., Han, Z. B., Hu, C. Y., and Pan, J. M.: Particulate barium flux
and its relationship with export production on the continental shelf of Prydz
Bay, east Antarctica, Mar. Chem., 157, 86–92, 2013.
Sweeney, C.: The annual cycle of surface water CO2 and O2
in the Ross Sea: a model for gas exchange on the continental shelves of
Antarctic, Biogeochemistry of the Ross Sea, Ant. Res. Ser., 78, 295–312,
2002.
Sweeney, C., Hansell, D. A., Carlson, C. A., Codispoti, L. A., Gordon, L. I.,
Marra, J., Millero, F. J., Smith, W. O., and Takahashi, T.: Biogeochemical
regimes, net community production and carbon export in the Ross Sea,
Antarctica, Deep-Sea Res. Pt. II, 47, 3369–3394, 2000.
Takahashi, T., Feely, R. A., Weiss, R. F., Wanninkhof, R. H., Chipman, D. W.,
Sutherland, S. C., and Takahashi, T. T.: Global sea air CO2 flux
based on climatological surface ocean pCO2, and seasonal
biological and temperature effects, Deep-Sea Res. Pt. II, 49, 1601–1622,
2002.
Takahashi, T., Sutherland, S. C., Wanninkhof, R., Sweeney, C., Feely, R. A.,
Chipman, D. W., Hales, B., Friederich, G., Chavez, F., Sabine, C., Watson, A.
J., Bakker, D. C., Schuster, U., Metzl, N., Yoshikawa-Inoue, H., Ishii, M.,
Midorikawa, T., Nojiri, Y., Körtzinger, A., Steinhoff, T., Hoppema, M.,
Olafsson, J., Arnarson, T. S., Tilbrook, B., Johannessen, T., Olsen, A.,
Bellerby, R., Wong, C. S., Delille, B., Bates, N. R., and de Baar, H. J. W.:
Climatological mean and decadal change in surface ocean
pCO2, and net sea-air CO2 flux over the global
oceans, Deep-Sea Res. Pt. II, 56, 554–577, 2009.
Takahashi, T., Sweeney, C., Hales, B., Chipman, D. W., Newberger, T.,
Goddard, J. G., Iannuzzi, R. A., and Sutherland, S. C.: The changing carbon
cycle in the Southern Ocean, Oceanography, 25, 26–37, 2012.
Telszewski, M., Chazottes, A., Schuster, U., Watson, A. J., Moulin, C.,
Bakker, D. C. E., González-Dávila, M., Johannessen, T.,
Körtzinger, A., Lüger, H., Olsen, A., Omar, A., Padin, X. A.,
Ríos, A. F., Steinhoff, T., Santana-Casiano, M., Wallace, D. W. R., and
Wanninkhof, R.: Estimating the monthly pCO2 distribution in
the North Atlantic using a self-organizing neural network, Biogeosciences, 6,
1405–1421, https://doi.org/10.5194/bg-6-1405-2009, 2009.
Thomson, R. E. and Fine, I. V.: Estimating mixed layer depth from oceanic
profile data, J. Atmos. Ocean. Technol., 20, 319–329, 2003.
Ultsch, A. and Röske, F.: Self-organizing feature maps predicting sea
levels, Inform. Sciences, 144, 91–125, 2002.
Vesanto, J.: Data Exploration Process Based on the Self-Organizing Map, Acta
Polytechnica Scandinavica, Mathematics and Computing Series, 115, 96 pp.,
2002.
Wanninkhof, R.: Relationship between wind speed and gas exchange over the
ocean revisited, Limnol. Oceanogr.-Methods, 12, 351–362, 2014.
Weiss, R. F.: Carbon dioxide in water and seawater: The solubility of a
nonideal gas, Mar. Chem., 2, 201–215, 1974.
Worby, A. P., Geiger, C. A., Paget, M. J., Van Woert, M. L., Ackley, S. F.,
and De Liberty, T. L.: Thickness distribution of Antarctic sea ice, J.
Geophys. Res., 113, C05S92, https://doi.org/10.1029/2007JC004254, 2008.
Wu, L., Wang, R., Xiao, W., Ge, S., Chen, Z., and Krijgsman, W.:
Productivity-climate coupling recorded in Pleistocene sediments off Prydz Bay
(East Antarctica), Palaegeogr. Palaeocl., 485, 260–270, 2017.
Xu, S., Chen, L., Chen, H., Li, J., Lin, W., and Qi, D.: Sea-air
CO2 fluxes in the Southern Ocean for the late spring and early
summer in 2009, Remote Sens. Environ., 175, 158–166, 2016.
Yabuki, T., Suga, T., Hanawa, K., Matsuoka, K., Kiwada, H., and Watanabe, T.:
Possible source of the Antarctic Bottom Water in Prydz Bay region, J.
Oceanogr., 62, 649–655, https://doi.org/10.1007/s10872-006-0083-1, 2006.
Zeng, J., Nojiri, Y., Murphy, P. P., Wong, C. S., and Fujinuma, Y.: A
comparison of pCO2 distributions in the northern North
Pacific using results from a commercial vessel in 1995–1999, Deep-Sea Res.
Pt. II, 49, 5303–5315, 2002.
Zeng, J. Nojiri, Y., Nakaoka, S., Nakajima, H., and Shirai, T.: Surface ocean
CO2 in 1990–2011 modelled using a feed-forward neural network,
Geosci. Data J., 2, 47–51, https://doi.org/10.1002/gdj3.26, 2015.
Zeng, J., Matsunaga, T., Saigusa, N., Shirai, T., Nakaoka, S.-I., and Tan,
Z.-H.: Technical note: Evaluation of three machine learning models for
surface ocean CO2 mapping, Ocean Sci., 13, 303–313,
https://doi.org/10.5194/os-13-303-2017, 2017.
Short summary
In this study we applied the self-organizing map (SOM) method to estimate the oceanic pCO2 in Prydz Bay derived from its main controlling factors. The RMSE of the SOM-derived pCO2 was 22.14 µatm compared to SOCAT datasets. Our results showed that the monthly averaged uptake of atmospheric CO2 for February 2015 was 23.57±6.36 TgC. Strong potential anthropogenic CO2 uptake in the
shelf regionwill enhance ocean acidification (OA) in the deep water of Prydz Bay and subsequently affect deep OA.
In this study we applied the self-organizing map (SOM) method to estimate the oceanic pCO2 in...
Altmetrics
Final-revised paper
Preprint