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3. In the Wake of Deeper Convection: Nonsteady State Anthropogenic Carbon in the Greenland Sea.

Author

Olsen, Are, Rajasakaren, Balamuralli, Jeansson, Emil, Lauvset, Siv K., Omar, Abdirahman M., and Becker, Meike

Subjects
CARBON cycle, CARBON emissions, CARBON, ATMOSPHERIC carbon dioxide, CLIMATE research, WATER depth
Abstract

We evaluate changes in dissolved inorganic carbon (DIC) in the Greenland Sea between 2002 and 2016, a period characterized by increasing convection depths. We find a mid‐depth maximum in anthropogenic carbon (Cant) accumulation that occurred as waters at these depths were rejuvenated by deeper reaching convection; broadly, these waters have caught up with the atmospheric CO2 rise that had happened between the last time they were ventilated and 2002 and also tracked the atmospheric CO2 rise 2002–2016. The overlying waters only tracked the atmospheric CO2 rise 2002–2016. The mid‐depth maximum in Cant accumulation was not evident in estimates generated with commonly used multiple linear regression (MLR) methods. We analyze the reasons why and show that the eMLR(C*) method may not fully capture nonsteady state changes in Cant when applied along a single hydrographic section as done here. This nonsteady component equates to redistribution of C*, whose spatial gradients in the Greenland Sea are dominated by Cant. We also show that the regular extended multiple linear regression method is sensitive to loss of spatial DIC gradients, which now happens as more and more Cant enters the ocean. Our findings demonstrate that MLR‐based estimates of the Cant accumulation rate should not be taken at face value in highly dynamical ocean regions, such as the Greenland Sea, and the need for also considering the total change in DIC and how this is affected by natural processes. Further investigations into the ability of MLR methods to reproduce nonsteady state changes in Cant are encouraged. Plain Language Summary: The ocean holds vast quantities of carbon. Each year this inventory increases as the ocean absorbs a quarter of our CO2 emissions. Keeping track of ocean carbon is a key climate change research priority. Observations from the Greenland Sea indicate at first glance a steady rise in DIC concentrations in the upper approximately 1,500–2,000 m of the water column, roughly equal to what one would expect from the atmospheric CO2 rise. This is unusually deep compared to the rest of the global ocean but reflects the deep‐water formation that occurs in this region. A closer inspection of the data, however, reveals that the seemingly uneventful rise in carbon in this region is the net result of several counteracting processes. In response to deeper convection, mid‐depth waters have lost inorganic carbon generated by the remineralization of organic matter, natural carbon. This has been counteracted by an unusually large rise in their content of man‐made, or anthropogenic carbon. Widely adopted methods for estimating decadal rises in anthropogenic carbon struggle to quantify these changes, such that our ability to detect the nature of effects of climate variability and change on the efficiency of the ocean carbon sink can be questioned. Key Points: Deeper convection caused a mid‐depth maximum in the rate of anthropogenic carbon increase in the Greenland Sea from 2002 to 2016The mid‐depth maximum in anthropogenic carbon accumulation was not evident in estimates generated with multiple linear regression methodsNonsteady state anthropogenic carbon accumulation may bias the eMLR(C*) method when applied along a single hydrographic section [ABSTRACT FROM AUTHOR]

Published
2024
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4. Global Carbon Budget 2023

Author

Friedlingstein, Pierre, primary, O'Sullivan, Michael, additional, Jones, Matthew W., additional, Andrew, Robbie M., additional, Bakker, Dorothee C. E., additional, Hauck, Judith, additional, Landschützer, Peter, additional, Le Quéré, Corinne, additional, Luijkx, Ingrid T., additional, Peters, Glen P., additional, Peters, Wouter, additional, Pongratz, Julia, additional, Schwingshackl, Clemens, additional, Sitch, Stephen, additional, Canadell, Josep G., additional, Ciais, Philippe, additional, Jackson, Robert B., additional, Alin, Simone R., additional, Anthoni, Peter, additional, Barbero, Leticia, additional, Bates, Nicholas R., additional, Becker, Meike, additional, Bellouin, Nicolas, additional, Decharme, Bertrand, additional, Bopp, Laurent, additional, Brasika, Ida Bagus Mandhara, additional, Cadule, Patricia, additional, Chamberlain, Matthew A., additional, Chandra, Naveen, additional, Chau, Thi-Tuyet-Trang, additional, Chevallier, Frédéric, additional, Chini, Louise P., additional, Cronin, Margot, additional, Dou, Xinyu, additional, Enyo, Kazutaka, additional, Evans, Wiley, additional, Falk, Stefanie, additional, Feely, Richard A., additional, Feng, Liang, additional, Ford, Daniel J., additional, Gasser, Thomas, additional, Ghattas, Josefine, additional, Gkritzalis, Thanos, additional, Grassi, Giacomo, additional, Gregor, Luke, additional, Gruber, Nicolas, additional, Gürses, Özgür, additional, Harris, Ian, additional, Hefner, Matthew, additional, Heinke, Jens, additional, Houghton, Richard A., additional, Hurtt, George C., additional, Iida, Yosuke, additional, Ilyina, Tatiana, additional, Jacobson, Andrew R., additional, Jain, Atul, additional, Jarníková, Tereza, additional, Jersild, Annika, additional, Jiang, Fei, additional, Jin, Zhe, additional, Joos, Fortunat, additional, Kato, Etsushi, additional, Keeling, Ralph F., additional, Kennedy, Daniel, additional, Klein Goldewijk, Kees, additional, Knauer, Jürgen, additional, Korsbakken, Jan Ivar, additional, Körtzinger, Arne, additional, Lan, Xin, additional, Lefèvre, Nathalie, additional, Li, Hongmei, additional, Liu, Junjie, additional, Liu, Zhiqiang, additional, Ma, Lei, additional, Marland, Greg, additional, Mayot, Nicolas, additional, McGuire, Patrick C., additional, McKinley, Galen A., additional, Meyer, Gesa, additional, Morgan, Eric J., additional, Munro, David R., additional, Nakaoka, Shin-Ichiro, additional, Niwa, Yosuke, additional, O'Brien, Kevin M., additional, Olsen, Are, additional, Omar, Abdirahman M., additional, Ono, Tsuneo, additional, Paulsen, Melf, additional, Pierrot, Denis, additional, Pocock, Katie, additional, Poulter, Benjamin, additional, Powis, Carter M., additional, Rehder, Gregor, additional, Resplandy, Laure, additional, Robertson, Eddy, additional, Rödenbeck, Christian, additional, Rosan, Thais M., additional, Schwinger, Jörg, additional, Séférian, Roland, additional, Smallman, T. Luke, additional, Smith, Stephen M., additional, Sospedra-Alfonso, Reinel, additional, Sun, Qing, additional, Sutton, Adrienne J., additional, Sweeney, Colm, additional, Takao, Shintaro, additional, Tans, Pieter P., additional, Tian, Hanqin, additional, Tilbrook, Bronte, additional, Tsujino, Hiroyuki, additional, Tubiello, Francesco, additional, van der Werf, Guido R., additional, van Ooijen, Erik, additional, Wanninkhof, Rik, additional, Watanabe, Michio, additional, Wimart-Rousseau, Cathy, additional, Yang, Dongxu, additional, Yang, Xiaojuan, additional, Yuan, Wenping, additional, Yue, Xu, additional, Zaehle, Sönke, additional, Zeng, Jiye, additional, and Zheng, Bo, additional

Published
2023
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5. Supplementary material to "Global Carbon Budget 2023"

Author

Friedlingstein, Pierre, primary, O'Sullivan, Michael, additional, Jones, Matthew W., additional, Andrew, Robbie M., additional, Bakker, Dorothee C. E., additional, Hauck, Judith, additional, Landschützer, Peter, additional, Le Quéré, Corinne, additional, Luijkx, Ingrid T., additional, Peters, Glen P., additional, Peters, Wouter, additional, Pongratz, Julia, additional, Schwingshackl, Clemens, additional, Sitch, Stephen, additional, Canadell, Josep G., additional, Ciais, Philippe, additional, Jackson, Robert B., additional, Alin, Simone R., additional, Anthoni, Peter, additional, Barbero, Leticia, additional, Bates, Nicholas R., additional, Becker, Meike, additional, Bellouin, Nicolas, additional, Decharme, Bertrand, additional, Bopp, Laurent, additional, Brasika, Ida Bagus Mandhara, additional, Cadule, Patricia, additional, Chamberlain, Matthew A., additional, Chandra, Naveen, additional, Chau, Thi-Tuyet-Trang, additional, Chevallier, Frédéric, additional, Chini, Louise P., additional, Cronin, Margot, additional, Dou, Xinyu, additional, Enyo, Kazutaka, additional, Evans, Wiley, additional, Falk, Stefanie, additional, Feely, Richard A., additional, Feng, Liang, additional, Ford, Daniel. J., additional, Gasser, Thomas, additional, Ghattas, Josefine, additional, Gkritzalis, Thanos, additional, Grassi, Giacomo, additional, Gregor, Luke, additional, Gruber, Nicolas, additional, Gürses, Özgür, additional, Harris, Ian, additional, Hefner, Matthew, additional, Heinke, Jens, additional, Houghton, Richard A., additional, Hurtt, George C., additional, Iida, Yosuke, additional, Ilyina, Tatiana, additional, Jacobson, Andrew R., additional, Jain, Atul, additional, Jarníková, Tereza, additional, Jersild, Annika, additional, Jiang, Fei, additional, Jin, Zhe, additional, Joos, Fortunat, additional, Kato, Etsushi, additional, Keeling, Ralph F., additional, Kennedy, Daniel, additional, Klein Goldewijk, Kees, additional, Knauer, Jürgen, additional, Korsbakken, Jan Ivar, additional, Körtzinger, Arne, additional, Lan, Xin, additional, Lefèvre, Nathalie, additional, Li, Hongmei, additional, Liu, Junjie, additional, Liu, Zhiqiang, additional, Ma, Lei, additional, Marland, Greg, additional, Mayot, Nicolas, additional, McGuire, Patrick C., additional, McKinley, Galen A., additional, Meyer, Gesa, additional, Morgan, Eric J., additional, Munro, David R., additional, Nakaoka, Shin-Ichiro, additional, Niwa, Yosuke, additional, O'Brien, Kevin M., additional, Olsen, Are, additional, Omar, Abdirahman M., additional, Ono, Tsuneo, additional, Paulsen, Melf E., additional, Pierrot, Denis, additional, Pocock, Katie, additional, Poulter, Benjamin, additional, Powis, Carter M., additional, Rehder, Gregor, additional, Resplandy, Laure, additional, Robertson, Eddy, additional, Rödenbeck, Christian, additional, Rosan, Thais M., additional, Schwinger, Jörg, additional, Séférian, Roland, additional, Smallman, T. Luke, additional, Smith, Stephen M., additional, Sospedra-Alfonso, Reinel, additional, Sun, Qing, additional, Sutton, Adrienne J., additional, Sweeney, Colm, additional, Takao, Shintaro, additional, Tans, Pieter P., additional, Tian, Hanqin, additional, Tilbrook, Bronte, additional, Tsujino, Hiroyuki, additional, Tubiello, Francesco, additional, van der Werf, Guido R., additional, van Ooijen, Erik, additional, Wanninkhof, Rik, additional, Watanabe, Michio, additional, Wimart-Rousseau, Cathy, additional, Yang, Dongxu, additional, Yang, Xiaojuan, additional, Yuan, Wenping, additional, Yue, Xu, additional, Zaehle, Sönke, additional, Zeng, Jiye, additional, and Zheng, Bo, additional

Published
2023
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6. Global Carbon Budget 2023

Author

Friedlingstein, Pierre, O'Sullivan, Michael, Jones, Matthew W., Andrew, Robbie M., Bakker, Dorothee C. E., Hauck, Judith, Landschützer, Peter, Le Quéré, Corinne, Luijkx, Ingrid T., Peters, Glen P., Peters, Wouter, Pongratz, Julia, Schwingshackl, Clemens, Sitch, Stephen, Canadell, Josep G., Ciais, Philippe, Jackson, Robert B., Alin, Simone R., Anthoni, Peter, Barbero, Leticia, Bates, Nicholas R., Becker, Meike, Bellouin, Nicolas, Decharme, Bertrand, Bopp, Laurent, Brasika, Ida Bagus Mandhara, Cadule, Patricia, Chamberlain, Matthew A., Chandra, Naveen, Chau, Thi-Tuyet-Trang, Chevallier, Frédéric, Chini, Louise P., Cronin, Margot, Dou, Xinyu, Enyo, Kazutaka, Evans, Wiley, Falk, Stefanie, Feely, Richard A., Feng, Liang, Ford, Daniel J., Gasser, Thomas, Ghattas, Josefine, Gkritzalis, Thanos, Grassi, Giacomo, Gregor, Luke, Gruber, Nicolas, Gürses, Özgür, Harris, Ian, Hefner, Matthew, Heinke, Jens, Houghton, Richard A., Hurtt, George C., Iida, Yosuke, Ilyina, Tatiana, Jacobson, Andrew R., Jain, Atul, Jarníková, Tereza, Jersild, Annika, Jiang, Fei, Jin, Zhe, Joos, Fortunat, Kato, Etsushi, Keeling, Ralph F., Kennedy, Daniel, Klein Goldewijk, Kees, Knauer, Jürgen, Korsbakken, Jan Ivar, Körtzinger, Arne, Lan, Xin, Lefèvre, Nathalie, Li, Hongmei, Liu, Junjie, Liu, Zhiqiang, Ma, Lei, Marland, Greg, Mayot, Nicolas, McGuire, Patrick C., McKinley, Galen A., Meyer, Gesa, Morgan, Eric J., Munro, David R., Nakaoka, Shin-Ichiro, Niwa, Yosuke, O'Brien, Kevin M., Olsen, Are, Omar, Abdirahman M., Ono, Tsuneo, Paulsen, Melf, Pierrot, Denis, Pocock, Katie, Poulter, Benjamin, Powis, Carter M., Rehder, Gregor, Resplandy, Laure, Robertson, Eddy, Rödenbeck, Christian, Rosan, Thais M., Schwinger, Jörg, Séférian, Roland, Smallman, T. Luke, Smith, Stephen M., Sospedra-Alfonso, Reinel, Sun, Qing, Sutton, Adrienne J., Sweeney, Colm, Takao, Shintaro, Tans, Pieter P., Tian, Hanqin, Tilbrook, Bronte, Tsujino, Hiroyuki, Tubiello, Francesco, van der Werf, Guido R., van Ooijen, Erik, Wanninkhof, Rik, Watanabe, Michio, Wimart-Rousseau, Cathy, Yang, Dongxu, Yang, Xiaojuan, Yuan, Wenping, Yue, Xu, Zaehle, Sönke, Zeng, Jiye, Zheng, Bo, Friedlingstein, Pierre, O'Sullivan, Michael, Jones, Matthew W., Andrew, Robbie M., Bakker, Dorothee C. E., Hauck, Judith, Landschützer, Peter, Le Quéré, Corinne, Luijkx, Ingrid T., Peters, Glen P., Peters, Wouter, Pongratz, Julia, Schwingshackl, Clemens, Sitch, Stephen, Canadell, Josep G., Ciais, Philippe, Jackson, Robert B., Alin, Simone R., Anthoni, Peter, Barbero, Leticia, Bates, Nicholas R., Becker, Meike, Bellouin, Nicolas, Decharme, Bertrand, Bopp, Laurent, Brasika, Ida Bagus Mandhara, Cadule, Patricia, Chamberlain, Matthew A., Chandra, Naveen, Chau, Thi-Tuyet-Trang, Chevallier, Frédéric, Chini, Louise P., Cronin, Margot, Dou, Xinyu, Enyo, Kazutaka, Evans, Wiley, Falk, Stefanie, Feely, Richard A., Feng, Liang, Ford, Daniel J., Gasser, Thomas, Ghattas, Josefine, Gkritzalis, Thanos, Grassi, Giacomo, Gregor, Luke, Gruber, Nicolas, Gürses, Özgür, Harris, Ian, Hefner, Matthew, Heinke, Jens, Houghton, Richard A., Hurtt, George C., Iida, Yosuke, Ilyina, Tatiana, Jacobson, Andrew R., Jain, Atul, Jarníková, Tereza, Jersild, Annika, Jiang, Fei, Jin, Zhe, Joos, Fortunat, Kato, Etsushi, Keeling, Ralph F., Kennedy, Daniel, Klein Goldewijk, Kees, Knauer, Jürgen, Korsbakken, Jan Ivar, Körtzinger, Arne, Lan, Xin, Lefèvre, Nathalie, Li, Hongmei, Liu, Junjie, Liu, Zhiqiang, Ma, Lei, Marland, Greg, Mayot, Nicolas, McGuire, Patrick C., McKinley, Galen A., Meyer, Gesa, Morgan, Eric J., Munro, David R., Nakaoka, Shin-Ichiro, Niwa, Yosuke, O'Brien, Kevin M., Olsen, Are, Omar, Abdirahman M., Ono, Tsuneo, Paulsen, Melf, Pierrot, Denis, Pocock, Katie, Poulter, Benjamin, Powis, Carter M., Rehder, Gregor, Resplandy, Laure, Robertson, Eddy, Rödenbeck, Christian, Rosan, Thais M., Schwinger, Jörg, Séférian, Roland, Smallman, T. Luke, Smith, Stephen M., Sospedra-Alfonso, Reinel, Sun, Qing, Sutton, Adrienne J., Sweeney, Colm, Takao, Shintaro, Tans, Pieter P., Tian, Hanqin, Tilbrook, Bronte, Tsujino, Hiroyuki, Tubiello, Francesco, van der Werf, Guido R., van Ooijen, Erik, Wanninkhof, Rik, Watanabe, Michio, Wimart-Rousseau, Cathy, Yang, Dongxu, Yang, Xiaojuan, Yuan, Wenping, Yue, Xu, Zaehle, Sönke, Zeng, Jiye, and Zheng, Bo

Abstract

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere in a changing climate is critical to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe and synthesize data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (E-FOS) are based on energy statistics and cement production data, while emissions from land-use change (E-LUC), mainly deforestation, are based on land-use and land-use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly, and its growth rate (G(ATM)) is computed from the annual changes in concentration. The ocean CO2 sink (S-OCEAN) is estimated with global ocean biogeochemistry models and observation-based fCO(2) products. The terrestrial CO2 sink (S-LAND) is estimated with dynamic global vegetation models. Additional lines of evidence on land and ocean sinks are provided by atmospheric inversions, atmospheric oxygen measurements, and Earth system models. The resulting carbon budget imbalance (B-IM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and incomplete understanding of the contemporary carbon cycle. All uncertainties are reported as +/- 1 sigma. For the year 2022, E-FOS increased by 0.9% relative to 2021, with fossil emissions at 9.9 +/- 0.5 GtC yr(-1) (10.2 +/- 0.5 GtC yr(-1) when the cement carbonation sink is not included), and E-LUC was 1.2 +/- 0.7 GtC yr(-1), for a total anthropogenic CO2 emission (including the cement carbonation sink) of 11.1 +/- 0.8 GtC yr(-1) (40.7 +/- 3.2 GtCO(2) yr(-1)). Also, for 2022, G(ATM) was 4.6 +/- 0.2 GtC yr(-1) (2.18 +/- 0.1 ppm yr(-1); ppm denotes parts per million), S-OCEAN was 2.8 +/- 0.4 GtC yr(-1)

Published
2023
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7. Assurance offshore CO2 monitoring, a cross-disciplinary approach. 

Author

Alendal, Guttorm, primary, Blackford, Jerry, additional, Carpentier, Stefan, additional, Dankel, Dorothy J., additional, Dewar, Marius, additional, El Droubi, Sufyan, additional, Fagerås, Bjarte, additional, Gasda, Sarah E., additional, Olyenik, Anna, additional, Omar, Abdirahman, additional, Pawar, Rajesh, additional, Romanak, Katherine, additional, Snee, Darren, additional, Schütz, Sigrid E., additional, and Torabi, Parisa, additional

Published
2023
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11. Acidification of the Nordic Seas

Author

Fransner, Filippa, primary, Fröb, Friederike, additional, Tjiputra, Jerry, additional, Goris, Nadine, additional, Lauvset, Siv K., additional, Skjelvan, Ingunn, additional, Jeansson, Emil, additional, Omar, Abdirahman, additional, Chierici, Melissa, additional, Jones, Elizabeth, additional, Fransson, Agneta, additional, Ólafsdóttir, Sólveig R., additional, Johannessen, Truls, additional, and Olsen, Are, additional

Published
2022
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