Articles | Volume 12, issue 7
https://doi.org/10.5194/bg-12-2195-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bg-12-2195-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
15 Apr 2015
Research article |
| 15 Apr 2015
Radiative forcing bias of simulated surface albedo modifications linked to forest cover changes at northern latitudes
Industrial Ecology Program, Energy and Process Engineering, Norwegian University of Science and Technology, Høgskoleringen 5, E-1, 7491 Trondheim, Norway
Norwegian Forest and Landscape Institute, P.O. Box 115, 1431 Ås, Norway
Center for International Climate and Environmental Research – Oslo (CICERO), P.O. Box 1129, Blindern, 0318 Oslo, Norway
R. Astrup
Norwegian Forest and Landscape Institute, P.O. Box 115, 1431 Ås, Norway
C. Antón-Fernández
Norwegian Forest and Landscape Institute, P.O. Box 115, 1431 Ås, Norway
A. H. Strømman
Industrial Ecology Program, Energy and Process Engineering, Norwegian University of Science and Technology, Høgskoleringen 5, E-1, 7491 Trondheim, Norway
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María A. Burgos, Elisabeth Andrews, Gloria Titos, Angela Benedetti, Huisheng Bian, Virginie Buchard, Gabriele Curci, Zak Kipling, Alf Kirkevåg, Harri Kokkola, Anton Laakso, Julie Letertre-Danczak, Marianne T. Lund, Hitoshi Matsui, Gunnar Myhre, Cynthia Randles, Michael Schulz, Twan van Noije, Kai Zhang, Lucas Alados-Arboledas, Urs Baltensperger, Anne Jefferson, James Sherman, Junying Sun, Ernest Weingartner, and Paul Zieger
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The radiative forcing of the direct aerosol effects can be decomposed into clear-sky and cloudy-sky portions. In this study we use observational methods and two sets of multi-model global aerosol simulations over the industrial era to show that the contribution from cloudy-sky regions is likely weak.
Tao Tang, Drew Shindell, Yuqiang Zhang, Apostolos Voulgarakis, Jean-Francois Lamarque, Gunnar Myhre, Camilla W. Stjern, Gregory Faluvegi, and Bjørn H. Samset
Atmos. Chem. Phys., 20, 8251–8266, https://doi.org/10.5194/acp-20-8251-2020, https://doi.org/10.5194/acp-20-8251-2020, 2020
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By using climate simulations, we found that both CO2 and black carbon aerosols could reduce low-level cloud cover, which is mainly due to changes in relative humidity, cloud water, dynamics, and stability. Because the impact of cloud on solar radiation is in effect only during daytime, such cloud reduction could enhance solar heating, thereby raising the daily maximum temperature by 10–50 %, varying by region, which has great implications for extreme climate events and socioeconomic activity.
Nicolas Bellouin, Will Davies, Keith P. Shine, Johannes Quaas, Johannes Mülmenstädt, Piers M. Forster, Chris Smith, Lindsay Lee, Leighton Regayre, Guy Brasseur, Natalia Sudarchikova, Idir Bouarar, Olivier Boucher, and Gunnar Myhre
Earth Syst. Sci. Data, 12, 1649–1677, https://doi.org/10.5194/essd-12-1649-2020, https://doi.org/10.5194/essd-12-1649-2020, 2020
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Quantifying the imbalance in the Earth's energy budget caused by human activities is important to understand and predict climate changes. This study presents new estimates of the imbalance caused by changes in atmospheric concentrations of carbon dioxide, methane, ozone, and particles of pollution. Over the period 2003–2017, the overall imbalance has been positive, indicating that the climate system has gained energy and will warm further.
Julie M. Nicely, Bryan N. Duncan, Thomas F. Hanisco, Glenn M. Wolfe, Ross J. Salawitch, Makoto Deushi, Amund S. Haslerud, Patrick Jöckel, Béatrice Josse, Douglas E. Kinnison, Andrew Klekociuk, Michael E. Manyin, Virginie Marécal, Olaf Morgenstern, Lee T. Murray, Gunnar Myhre, Luke D. Oman, Giovanni Pitari, Andrea Pozzer, Ilaria Quaglia, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Kane Stone, Susan Strahan, Simone Tilmes, Holger Tost, Daniel M. Westervelt, and Guang Zeng
Atmos. Chem. Phys., 20, 1341–1361, https://doi.org/10.5194/acp-20-1341-2020, https://doi.org/10.5194/acp-20-1341-2020, 2020
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Differences in methane lifetime among global models are large and poorly understood. We use a neural network method and simulations from the Chemistry Climate Model Initiative to quantify the factors influencing methane lifetime spread among models and variations over time. UV photolysis, tropospheric ozone, and nitrogen oxides drive large model differences, while the same factors plus specific humidity contribute to a decreasing trend in methane lifetime between 1980 and 2015.
Marianne T. Lund, Gunnar Myhre, and Bjørn H. Samset
Atmos. Chem. Phys., 19, 13827–13839, https://doi.org/10.5194/acp-19-13827-2019, https://doi.org/10.5194/acp-19-13827-2019, 2019
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Atmospheric aerosols play an integral role in shaping local and global climate by modifying the energy balance, clouds and precipitation. They are also a leading cause of premature mortality in many areas. New scenarios provide projections of emissions until 2100 given strong, medium or weak air pollution control stringency. We quantify the consequent regional and global aerosol loading and radiative forcing, showing a large spread at the end of the century and regional differences in trends.
Øivind Hodnebrog, Gunnar Myhre, Bjørn H. Samset, Kari Alterskjær, Timothy Andrews, Olivier Boucher, Gregory Faluvegi, Dagmar Fläschner, Piers M. Forster, Matthew Kasoar, Alf Kirkevåg, Jean-Francois Lamarque, Dirk Olivié, Thomas B. Richardson, Dilshad Shawki, Drew Shindell, Keith P. Shine, Philip Stier, Toshihiko Takemura, Apostolos Voulgarakis, and Duncan Watson-Parris
Atmos. Chem. Phys., 19, 12887–12899, https://doi.org/10.5194/acp-19-12887-2019, https://doi.org/10.5194/acp-19-12887-2019, 2019
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Different greenhouse gases (e.g. CO2) and aerosols (e.g. black carbon) impact the Earth’s water cycle differently. Here we investigate how various gases and particles impact atmospheric water vapour and its lifetime, i.e., the average number of days that water vapour stays in the atmosphere after evaporation and before precipitation. We find that this lifetime could increase substantially by the end of this century, indicating that important changes in precipitation patterns are excepted.
Ryan M. Bright and Thomas L. O'Halloran
Geosci. Model Dev., 12, 3975–3990, https://doi.org/10.5194/gmd-12-3975-2019, https://doi.org/10.5194/gmd-12-3975-2019, 2019
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To determine the effects of land cover change on climate, researchers must be able to quantify the net change in energy (radiation) at the top of the atmosphere caused by changes in surface reflectance (albedo). Historically, this was done with sophisticated models that require detailed input datasets only available to specialists. Here we combine existing remotely sensed datasets and a new formulation to create a new model that is accurate, transparent, and easy to use.
Titta Majasalmi and Ryan M. Bright
Geosci. Model Dev., 12, 3923–3938, https://doi.org/10.5194/gmd-12-3923-2019, https://doi.org/10.5194/gmd-12-3923-2019, 2019
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Many land surface models rely on solutions derived from two-stream approximations utilizing leaf-level optical properties, many of which have not been formally reviewed or published. Using plant functional type groupings of the Community Land Model (CLM), we found large deviations between measured and CLM default near-infrared optical properties, implying that the modeled shortwave radiation budget including surface albedo may be expected to change after updating the biased parameters.
Marianne Tronstad Lund, Gunnar Myhre, Amund Søvde Haslerud, Ragnhild Bieltvedt Skeie, Jan Griesfeller, Stephen Matthew Platt, Rajesh Kumar, Cathrine Lund Myhre, and Michael Schulz
Geosci. Model Dev., 11, 4909–4931, https://doi.org/10.5194/gmd-11-4909-2018, https://doi.org/10.5194/gmd-11-4909-2018, 2018
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Atmospheric aerosols play a key role in the climate system, but their exact impact on the energy balance remains uncertain. Accurate representation of the geographical distribution and properties of aerosols in global models is key to reduce this uncertainty. Here we use a new emission inventory and a range of observations to carefully validate a state-of-the-art model and present an updated estimate of the net direct effect of anthropogenic aerosols since the preindustrial era.
Ragnhild Bieltvedt Skeie, Terje Berntsen, Magne Aldrin, Marit Holden, and Gunnar Myhre
Earth Syst. Dynam., 9, 879–894, https://doi.org/10.5194/esd-9-879-2018, https://doi.org/10.5194/esd-9-879-2018, 2018
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A key question in climate science is how the global mean surface temperature responds to changes in greenhouse gases. This dependency is quantified by the climate sensitivity, which is determined by the complex feedbacks in the climate system. In this study observations of past climate change are used to estimate this sensitivity. Our estimate is consistent with values for the equilibrium climate sensitivity estimated by complex climate models but sensitive to the use of uncertain input data.
Tao Tang, Drew Shindell, Bjørn H. Samset, Oliviér Boucher, Piers M. Forster, Øivind Hodnebrog, Gunnar Myhre, Jana Sillmann, Apostolos Voulgarakis, Timothy Andrews, Gregory Faluvegi, Dagmar Fläschner, Trond Iversen, Matthew Kasoar, Viatcheslav Kharin, Alf Kirkevåg, Jean-Francois Lamarque, Dirk Olivié, Thomas Richardson, Camilla W. Stjern, and Toshihiko Takemura
Atmos. Chem. Phys., 18, 8439–8452, https://doi.org/10.5194/acp-18-8439-2018, https://doi.org/10.5194/acp-18-8439-2018, 2018
Titta Majasalmi, Stephanie Eisner, Rasmus Astrup, Jonas Fridman, and Ryan M. Bright
Biogeosciences, 15, 399–412, https://doi.org/10.5194/bg-15-399-2018, https://doi.org/10.5194/bg-15-399-2018, 2018
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Forest management shapes forest structure and in turn surface–atmosphere interactions. We used Fennoscandian forest maps and inventory data to develop a classification system for forest structure. The classification was integrated with the ESA Climate Change Initiative land cover map to achieve complete surface representation. The result is an improved product for modeling surface–atmosphere exchanges in regions with intensively managed forests.
Sunil Vadakkepuliyambatta, Ragnhild B. Skeie, Gunnar Myhre, Stig B. Dalsøren, Anna Silyakova, Norbert Schmidbauer, Cathrine Lund Myhre, and Jürgen Mienert
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2017-110, https://doi.org/10.5194/esd-2017-110, 2017
Preprint retracted
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Release of methane, one of the major greenhouse gases, from melting hydrates has been proposed as a mechanism that accelerated global warming in the past. We focus on Arctic Ocean warming as a robust case study for accelerated melting of hydrates, assessing the impact of Arctic methane release on global air temperatures during the next century. Contrary to popular belief, it is shown that methane emissions from melting hydrates from the Arctic seafloor is not a major driver of global warming.
Huisheng Bian, Mian Chin, Didier A. Hauglustaine, Michael Schulz, Gunnar Myhre, Susanne E. Bauer, Marianne T. Lund, Vlassis A. Karydis, Tom L. Kucsera, Xiaohua Pan, Andrea Pozzer, Ragnhild B. Skeie, Stephen D. Steenrod, Kengo Sudo, Kostas Tsigaridis, Alexandra P. Tsimpidi, and Svetlana G. Tsyro
Atmos. Chem. Phys., 17, 12911–12940, https://doi.org/10.5194/acp-17-12911-2017, https://doi.org/10.5194/acp-17-12911-2017, 2017
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Atmospheric nitrate contributes notably to total aerosol mass in the present day and is likely to be more important over the next century, with a projected decline in SO2 and NOx emissions and increase in NH3 emissions. This paper investigates atmospheric nitrate using multiple global models and measurements. The study is part of the AeroCom phase III activity. The study is the first attempt to look at global atmospheric nitrate simulation at physical and chemical process levels.
Maria Sand, Bjørn H. Samset, Yves Balkanski, Susanne Bauer, Nicolas Bellouin, Terje K. Berntsen, Huisheng Bian, Mian Chin, Thomas Diehl, Richard Easter, Steven J. Ghan, Trond Iversen, Alf Kirkevåg, Jean-François Lamarque, Guangxing Lin, Xiaohong Liu, Gan Luo, Gunnar Myhre, Twan van Noije, Joyce E. Penner, Michael Schulz, Øyvind Seland, Ragnhild B. Skeie, Philip Stier, Toshihiko Takemura, Kostas Tsigaridis, Fangqun Yu, Kai Zhang, and Hua Zhang
Atmos. Chem. Phys., 17, 12197–12218, https://doi.org/10.5194/acp-17-12197-2017, https://doi.org/10.5194/acp-17-12197-2017, 2017
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The role of aerosols in the changing polar climate is not well understood and the aerosols are poorly constrained in the models. In this study we have compared output from 16 different aerosol models with available observations at both poles. We show that the model median is representative of the observations, but the model spread is large. The Arctic direct aerosol radiative effect over the industrial area is positive during spring due to black carbon and negative during summer due to sulfate.
Gunnar Myhre, Wenche Aas, Ribu Cherian, William Collins, Greg Faluvegi, Mark Flanner, Piers Forster, Øivind Hodnebrog, Zbigniew Klimont, Marianne T. Lund, Johannes Mülmenstädt, Cathrine Lund Myhre, Dirk Olivié, Michael Prather, Johannes Quaas, Bjørn H. Samset, Jordan L. Schnell, Michael Schulz, Drew Shindell, Ragnhild B. Skeie, Toshihiko Takemura, and Svetlana Tsyro
Atmos. Chem. Phys., 17, 2709–2720, https://doi.org/10.5194/acp-17-2709-2017, https://doi.org/10.5194/acp-17-2709-2017, 2017
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Over the past decades, the geographical distribution of emissions of substances that alter the atmospheric energy balance has changed due to economic growth and pollution regulations. Here, we show the resulting changes to aerosol and ozone abundances and their radiative forcing using recently updated emission data for the period 1990–2015, as simulated by seven global atmospheric composition models. The global mean radiative forcing is more strongly positive than reported in IPCC AR5.
William J. Collins, Jean-François Lamarque, Michael Schulz, Olivier Boucher, Veronika Eyring, Michaela I. Hegglin, Amanda Maycock, Gunnar Myhre, Michael Prather, Drew Shindell, and Steven J. Smith
Geosci. Model Dev., 10, 585–607, https://doi.org/10.5194/gmd-10-585-2017, https://doi.org/10.5194/gmd-10-585-2017, 2017
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We have designed a set of climate model experiments called the Aerosol Chemistry Model Intercomparison Project (AerChemMIP). These are designed to quantify the climate and air quality impacts of aerosols and chemically reactive gases in the climate models that are used to simulate past and future climate. We hope that many climate modelling centres will choose to run these experiments to help understand the contribution of aerosols and chemistry to climate change.
Nicolas Bellouin, Laura Baker, Øivind Hodnebrog, Dirk Olivié, Ribu Cherian, Claire Macintosh, Bjørn Samset, Anna Esteve, Borgar Aamaas, Johannes Quaas, and Gunnar Myhre
Atmos. Chem. Phys., 16, 13885–13910, https://doi.org/10.5194/acp-16-13885-2016, https://doi.org/10.5194/acp-16-13885-2016, 2016
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This study uses global climate models to quantify how strongly man-made emissions of selected pollutants modify the energy budget of the Earth. The pollutants studied interact directly and indirectly with sunlight and terrestrial radiation and remain a relatively short time in the atmosphere, leading to regional and seasonal variations in their impacts. This new data set is useful to compare the potential climate impacts of different pollutants in support of policies to reduce climate change.
Camilla Weum Stjern, Bjørn Hallvard Samset, Gunnar Myhre, Huisheng Bian, Mian Chin, Yanko Davila, Frank Dentener, Louisa Emmons, Johannes Flemming, Amund Søvde Haslerud, Daven Henze, Jan Eiof Jonson, Tom Kucsera, Marianne Tronstad Lund, Michael Schulz, Kengo Sudo, Toshihiko Takemura, and Simone Tilmes
Atmos. Chem. Phys., 16, 13579–13599, https://doi.org/10.5194/acp-16-13579-2016, https://doi.org/10.5194/acp-16-13579-2016, 2016
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Air pollution can reach distant regions through intercontinental transport. Here we first present results from the Hemispheric Transport of Air Pollution Phase 2 exercise, where many models performed the same set of coordinated emission-reduction experiments. We find that mitigations have considerable extra-regional effects, and show that this is particularly true for black carbon emissions, as long-range transport elevates aerosols to higher levels where their radiative influence is stronger.
B. Quennehen, J.-C. Raut, K. S. Law, N. Daskalakis, G. Ancellet, C. Clerbaux, S.-W. Kim, M. T. Lund, G. Myhre, D. J. L. Olivié, S. Safieddine, R. B. Skeie, J. L. Thomas, S. Tsyro, A. Bazureau, N. Bellouin, M. Hu, M. Kanakidou, Z. Klimont, K. Kupiainen, S. Myriokefalitakis, J. Quaas, S. T. Rumbold, M. Schulz, R. Cherian, A. Shimizu, J. Wang, S.-C. Yoon, and T. Zhu
Atmos. Chem. Phys., 16, 10765–10792, https://doi.org/10.5194/acp-16-10765-2016, https://doi.org/10.5194/acp-16-10765-2016, 2016
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This paper evaluates the ability of six global models and one regional model in reproducing short-lived pollutants (defined here as ozone and its precursors, aerosols and black carbon) concentrations over Asia using satellite, ground-based and airborne observations.
Key findings are that models homogeneously reproduce the trace gas observations although nitrous oxides are underestimated, whereas the aerosol distributions are heterogeneously reproduced, implicating important uncertainties.
Stig B. Dalsøren, Cathrine L. Myhre, Gunnar Myhre, Angel J. Gomez-Pelaez, Ole A. Søvde, Ivar S. A. Isaksen, Ray F. Weiss, and Christina M. Harth
Atmos. Chem. Phys., 16, 3099–3126, https://doi.org/10.5194/acp-16-3099-2016, https://doi.org/10.5194/acp-16-3099-2016, 2016
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Methane is a key greenhouse gas. Observations at surface sites show a more than 10 % increase over the period 1984–2012. Using an atmospheric model we calculate a growth in the atmospheric chemical methane loss the last decades. Without this, the rise in atmospheric methane would have been even higher. The model reproduces trends and short-term variations in observation data. However, some discrepancies in model performance question the accuracy in estimates of emission increases in Asia.
A. Stohl, B. Aamaas, M. Amann, L. H. Baker, N. Bellouin, T. K. Berntsen, O. Boucher, R. Cherian, W. Collins, N. Daskalakis, M. Dusinska, S. Eckhardt, J. S. Fuglestvedt, M. Harju, C. Heyes, Ø. Hodnebrog, J. Hao, U. Im, M. Kanakidou, Z. Klimont, K. Kupiainen, K. S. Law, M. T. Lund, R. Maas, C. R. MacIntosh, G. Myhre, S. Myriokefalitakis, D. Olivié, J. Quaas, B. Quennehen, J.-C. Raut, S. T. Rumbold, B. H. Samset, M. Schulz, Ø. Seland, K. P. Shine, R. B. Skeie, S. Wang, K. E. Yttri, and T. Zhu
Atmos. Chem. Phys., 15, 10529–10566, https://doi.org/10.5194/acp-15-10529-2015, https://doi.org/10.5194/acp-15-10529-2015, 2015
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This paper presents a summary of the findings of the ECLIPSE EU project. The project has investigated the climate and air quality impacts of short-lived climate pollutants (especially methane, ozone, aerosols) and has designed a global mitigation strategy that maximizes co-benefits between air quality and climate policy. Transient climate model simulations allowed quantifying the impacts on temperature (e.g., reduction in global warming by 0.22K for the decade 2041-2050) and precipitation.
L. H. Baker, W. J. Collins, D. J. L. Olivié, R. Cherian, Ø. Hodnebrog, G. Myhre, and J. Quaas
Atmos. Chem. Phys., 15, 8201–8216, https://doi.org/10.5194/acp-15-8201-2015, https://doi.org/10.5194/acp-15-8201-2015, 2015
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We investigate the impact of removing land-based anthropogenic emissions of three aerosol species, using four fully-coupled atmosphere-ocean global climate models. Removing SO2 emissions leads to warming globally, strongest in the Northern Hemisphere (NH), and an increase in NH precipitation. Organic and black carbon (OC, BC) have a weaker impact, and less certainty on the response; OC (BC) removal shows a weak overall warming (cooling), and both show small increases in precipitation globally.
G. Myhre and B. H. Samset
Atmos. Chem. Phys., 15, 2883–2888, https://doi.org/10.5194/acp-15-2883-2015, https://doi.org/10.5194/acp-15-2883-2015, 2015
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Radiative forcing (RF) of black carbon (BC) in the atmosphere is estimated using radiative transfer codes of various complexities. Here we show that the two-stream radiative transfer codes used most in climate models give overly strong forward scattering, leading to enhanced absorption at the surface and overly weak absorption by BC. Such calculations are found to underestimate RF in all sky conditions by 10% for global mean, relative to the more sophisticated multi-stream model.
B. H. Samset, G. Myhre, A. Herber, Y. Kondo, S.-M. Li, N. Moteki, M. Koike, N. Oshima, J. P. Schwarz, Y. Balkanski, S. E. Bauer, N. Bellouin, T. K. Berntsen, H. Bian, M. Chin, T. Diehl, R. C. Easter, S. J. Ghan, T. Iversen, A. Kirkevåg, J.-F. Lamarque, G. Lin, X. Liu, J. E. Penner, M. Schulz, Ø. Seland, R. B. Skeie, P. Stier, T. Takemura, K. Tsigaridis, and K. Zhang
Atmos. Chem. Phys., 14, 12465–12477, https://doi.org/10.5194/acp-14-12465-2014, https://doi.org/10.5194/acp-14-12465-2014, 2014
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Far from black carbon (BC) emission sources, present climate models are unable to reproduce flight measurements. By comparing recent models with data, we find that the atmospheric lifetime of BC may be overestimated in models. By adjusting modeled BC concentrations to measurements in remote regions - over oceans and at high altitudes - we arrive at a reduced estimate for BC radiative forcing over the industrial era.
K. Tsigaridis, N. Daskalakis, M. Kanakidou, P. J. Adams, P. Artaxo, R. Bahadur, Y. Balkanski, S. E. Bauer, N. Bellouin, A. Benedetti, T. Bergman, T. K. Berntsen, J. P. Beukes, H. Bian, K. S. Carslaw, M. Chin, G. Curci, T. Diehl, R. C. Easter, S. J. Ghan, S. L. Gong, A. Hodzic, C. R. Hoyle, T. Iversen, S. Jathar, J. L. Jimenez, J. W. Kaiser, A. Kirkevåg, D. Koch, H. Kokkola, Y. H Lee, G. Lin, X. Liu, G. Luo, X. Ma, G. W. Mann, N. Mihalopoulos, J.-J. Morcrette, J.-F. Müller, G. Myhre, S. Myriokefalitakis, N. L. Ng, D. O'Donnell, J. E. Penner, L. Pozzoli, K. J. Pringle, L. M. Russell, M. Schulz, J. Sciare, Ø. Seland, D. T. Shindell, S. Sillman, R. B. Skeie, D. Spracklen, T. Stavrakou, S. D. Steenrod, T. Takemura, P. Tiitta, S. Tilmes, H. Tost, T. van Noije, P. G. van Zyl, K. von Salzen, F. Yu, Z. Wang, Z. Wang, R. A. Zaveri, H. Zhang, K. Zhang, Q. Zhang, and X. Zhang
Atmos. Chem. Phys., 14, 10845–10895, https://doi.org/10.5194/acp-14-10845-2014, https://doi.org/10.5194/acp-14-10845-2014, 2014
J. Huttunen, A. Arola, G. Myhre, A. V. Lindfors, T. Mielonen, S. Mikkonen, J. S. Schafer, S. N. Tripathi, M. Wild, M. Komppula, and K. E. J. Lehtinen
Atmos. Chem. Phys., 14, 6103–6110, https://doi.org/10.5194/acp-14-6103-2014, https://doi.org/10.5194/acp-14-6103-2014, 2014
R. B. Skeie, T. Berntsen, M. Aldrin, M. Holden, and G. Myhre
Earth Syst. Dynam., 5, 139–175, https://doi.org/10.5194/esd-5-139-2014, https://doi.org/10.5194/esd-5-139-2014, 2014
R. M. Bright and M. M. Kvalevåg
Atmos. Chem. Phys., 13, 11169–11174, https://doi.org/10.5194/acp-13-11169-2013, https://doi.org/10.5194/acp-13-11169-2013, 2013
A. Arola, T. F. Eck, J. Huttunen, K. E. J. Lehtinen, A. V. Lindfors, G. Myhre, A. Smirnov, S. N. Tripathi, and H. Yu
Atmos. Chem. Phys., 13, 7895–7901, https://doi.org/10.5194/acp-13-7895-2013, https://doi.org/10.5194/acp-13-7895-2013, 2013
M. S. Eide, S. B. Dalsøren, Ø. Endresen, B. Samset, G. Myhre, J. Fuglestvedt, and T. Berntsen
Atmos. Chem. Phys., 13, 4183–4201, https://doi.org/10.5194/acp-13-4183-2013, https://doi.org/10.5194/acp-13-4183-2013, 2013
K. W. Bowman, D. T. Shindell, H. M. Worden, J.F. Lamarque, P. J. Young, D. S. Stevenson, Z. Qu, M. de la Torre, D. Bergmann, P. J. Cameron-Smith, W. J. Collins, R. Doherty, S. B. Dalsøren, G. Faluvegi, G. Folberth, L. W. Horowitz, B. M. Josse, Y. H. Lee, I. A. MacKenzie, G. Myhre, T. Nagashima, V. Naik, D. A. Plummer, S. T. Rumbold, R. B. Skeie, S. A. Strode, K. Sudo, S. Szopa, A. Voulgarakis, G. Zeng, S. S. Kulawik, A. M. Aghedo, and J. R. Worden
Atmos. Chem. Phys., 13, 4057–4072, https://doi.org/10.5194/acp-13-4057-2013, https://doi.org/10.5194/acp-13-4057-2013, 2013
P. Stier, N. A. J. Schutgens, N. Bellouin, H. Bian, O. Boucher, M. Chin, S. Ghan, N. Huneeus, S. Kinne, G. Lin, X. Ma, G. Myhre, J. E. Penner, C. A. Randles, B. Samset, M. Schulz, T. Takemura, F. Yu, H. Yu, and C. Zhou
Atmos. Chem. Phys., 13, 3245–3270, https://doi.org/10.5194/acp-13-3245-2013, https://doi.org/10.5194/acp-13-3245-2013, 2013
D. T. Shindell, J.-F. Lamarque, M. Schulz, M. Flanner, C. Jiao, M. Chin, P. J. Young, Y. H. Lee, L. Rotstayn, N. Mahowald, G. Milly, G. Faluvegi, Y. Balkanski, W. J. Collins, A. J. Conley, S. Dalsoren, R. Easter, S. Ghan, L. Horowitz, X. Liu, G. Myhre, T. Nagashima, V. Naik, S. T. Rumbold, R. Skeie, K. Sudo, S. Szopa, T. Takemura, A. Voulgarakis, J.-H. Yoon, and F. Lo
Atmos. Chem. Phys., 13, 2939–2974, https://doi.org/10.5194/acp-13-2939-2013, https://doi.org/10.5194/acp-13-2939-2013, 2013
D. S. Stevenson, P. J. Young, V. Naik, J.-F. Lamarque, D. T. Shindell, A. Voulgarakis, R. B. Skeie, S. B. Dalsoren, G. Myhre, T. K. Berntsen, G. A. Folberth, S. T. Rumbold, W. J. Collins, I. A. MacKenzie, R. M. Doherty, G. Zeng, T. P. C. van Noije, A. Strunk, D. Bergmann, P. Cameron-Smith, D. A. Plummer, S. A. Strode, L. Horowitz, Y. H. Lee, S. Szopa, K. Sudo, T. Nagashima, B. Josse, I. Cionni, M. Righi, V. Eyring, A. Conley, K. W. Bowman, O. Wild, and A. Archibald
Atmos. Chem. Phys., 13, 3063–3085, https://doi.org/10.5194/acp-13-3063-2013, https://doi.org/10.5194/acp-13-3063-2013, 2013
Y. H. Lee, J.-F. Lamarque, M. G. Flanner, C. Jiao, D. T. Shindell, T. Berntsen, M. M. Bisiaux, J. Cao, W. J. Collins, M. Curran, R. Edwards, G. Faluvegi, S. Ghan, L. W. Horowitz, J. R. McConnell, J. Ming, G. Myhre, T. Nagashima, V. Naik, S. T. Rumbold, R. B. Skeie, K. Sudo, T. Takemura, F. Thevenon, B. Xu, and J.-H. Yoon
Atmos. Chem. Phys., 13, 2607–2634, https://doi.org/10.5194/acp-13-2607-2013, https://doi.org/10.5194/acp-13-2607-2013, 2013
C. A. Randles, S. Kinne, G. Myhre, M. Schulz, P. Stier, J. Fischer, L. Doppler, E. Highwood, C. Ryder, B. Harris, J. Huttunen, Y. Ma, R. T. Pinker, B. Mayer, D. Neubauer, R. Hitzenberger, L. Oreopoulos, D. Lee, G. Pitari, G. Di Genova, J. Quaas, F. G. Rose, S. Kato, S. T. Rumbold, I. Vardavas, N. Hatzianastassiou, C. Matsoukas, H. Yu, F. Zhang, H. Zhang, and P. Lu
Atmos. Chem. Phys., 13, 2347–2379, https://doi.org/10.5194/acp-13-2347-2013, https://doi.org/10.5194/acp-13-2347-2013, 2013
B. H. Samset, G. Myhre, M. Schulz, Y. Balkanski, S. Bauer, T. K. Berntsen, H. Bian, N. Bellouin, T. Diehl, R. C. Easter, S. J. Ghan, T. Iversen, S. Kinne, A. Kirkevåg, J.-F. Lamarque, G. Lin, X. Liu, J. E. Penner, Ø. Seland, R. B. Skeie, P. Stier, T. Takemura, K. Tsigaridis, and K. Zhang
Atmos. Chem. Phys., 13, 2423–2434, https://doi.org/10.5194/acp-13-2423-2013, https://doi.org/10.5194/acp-13-2423-2013, 2013
S. B. Dalsøren, B. H. Samset, G. Myhre, J. J. Corbett, R. Minjares, D. Lack, and J. S. Fuglestvedt
Atmos. Chem. Phys., 13, 1941–1955, https://doi.org/10.5194/acp-13-1941-2013, https://doi.org/10.5194/acp-13-1941-2013, 2013
G. Myhre, B. H. Samset, M. Schulz, Y. Balkanski, S. Bauer, T. K. Berntsen, H. Bian, N. Bellouin, M. Chin, T. Diehl, R. C. Easter, J. Feichter, S. J. Ghan, D. Hauglustaine, T. Iversen, S. Kinne, A. Kirkevåg, J.-F. Lamarque, G. Lin, X. Liu, M. T. Lund, G. Luo, X. Ma, T. van Noije, J. E. Penner, P. J. Rasch, A. Ruiz, Ø. Seland, R. B. Skeie, P. Stier, T. Takemura, K. Tsigaridis, P. Wang, Z. Wang, L. Xu, H. Yu, F. Yu, J.-H. Yoon, K. Zhang, H. Zhang, and C. Zhou
Atmos. Chem. Phys., 13, 1853–1877, https://doi.org/10.5194/acp-13-1853-2013, https://doi.org/10.5194/acp-13-1853-2013, 2013
C. D. Holmes, M. J. Prather, O. A. Søvde, and G. Myhre
Atmos. Chem. Phys., 13, 285–302, https://doi.org/10.5194/acp-13-285-2013, https://doi.org/10.5194/acp-13-285-2013, 2013
Ø. Hodnebrog, T. K. Berntsen, O. Dessens, M. Gauss, V. Grewe, I. S. A. Isaksen, B. Koffi, G. Myhre, D. Olivié, M. J. Prather, F. Stordal, S. Szopa, Q. Tang, P. van Velthoven, and J. E. Williams
Atmos. Chem. Phys., 12, 12211–12225, https://doi.org/10.5194/acp-12-12211-2012, https://doi.org/10.5194/acp-12-12211-2012, 2012
Related subject area
Earth System Science/Response to Global Change: Climate Change
The effectiveness of agricultural carbon dioxide removal using the University of Victoria Earth System Climate Model
Consistency of global carbon budget between concentration- and emission-driven historical experiments simulated by CMIP6 Earth system models and suggestions for improved simulation of CO2 concentration
Selecting allometric equations to estimate forest biomass from plot- rather than individual-level predictive performance
Impact of winter warming on CO2 fluxes in evergreen needleleaf forests
Effects of pH/pCO2 fluctuations on photosynthesis and fatty acid composition of two marine diatoms, with reference to consequences of coastal acidification
Long-term impacts of global temperature stabilization and overshoot on exploited marine species
Modelling ozone-induced changes in wheat amino acids and protein quality using a process-based crop model
Toward more robust net primary production projections in the North Atlantic Ocean
Assessment framework to predict sensitivity of marine calcifiers to ocean alkalinity enhancement – identification of biological thresholds and importance of precautionary principle
Review and syntheses: Ocean alkalinity enhancement and carbon dioxide removal through marine enhanced rock weathering using olivine
Southern Hemisphere tree-rings as proxies to reconstruct Southern Ocean upwelling
Particle fluxes by subtropical pelagic communities under ocean alkalinity enhancement
Responses of field-grown maize to different soil types, water regimes, and contrasting vapor pressure deficit
Effect of the 2022 summer drought across forest types in Europe
Simulating vertical phytoplankton dynamics in a stratified ocean using a two-layered ecosystem model
Ozone pollution may limit the benefits of irrigation to wheat productivity in India
Effect of terrestrial nutrient limitation on the estimation of the remaining carbon budget
Projected changes in forest fire season, the number of fires, and burnt area in Fennoscandia by 2100
New ozone–nitrogen model shows early senescence onset is the primary cause of ozone-induced reduction in grain quality of wheat
Ocean alkalinity enhancement approaches and the predictability of runaway precipitation processes: results of an experimental study to determine critical alkalinity ranges for safe and sustainable application scenarios
Variations of polyphenols and carbohydrates of Emiliania huxleyi grown under simulated ocean acidification conditions
Assessing the lifetime of anthropogenic CO2 and its sensitivity to different carbon cycle processes
Foliar nutrient uptake from dust sustains plant nutrition
Global and regional hydrological impacts of global forest expansion
Sensitivity of tropical woodland savannas to El Niño droughts
The biological and preformed carbon pumps in perpetually slower and warmer oceans
The Southern Ocean as the climate's freight train – driving ongoing global warming under zero-emission scenarios with ACCESS-ESM1.5
Mapping the future afforestation distribution of China constrained by a national afforestation plan and climate change
Southern Ocean phytoplankton under climate change: a shifting balance of bottom-up and top-down control
Coherency and time lag analyses between MODIS vegetation indices and climate across forests and grasslands in the European temperate zone
Direct foliar phosphorus uptake from wildfire ash
Disentangling future effects of climate change and forest disturbance on vegetation composition and land-surface properties of the boreal forest
The effect of forest cover changes on the regional climate conditions in Europe during the period 1986–2015
Carbon cycle feedbacks in an idealized simulation and a scenario simulation of negative emissions in CMIP6 Earth system models
Spatiotemporal heterogeneity in the increase in ocean acidity extremes in the northeastern Pacific
Anthropogenic climate change drives non-stationary phytoplankton internal variability
The response of wildfire regimes to Last Glacial Maximum carbon dioxide and climate
Simulated responses of soil carbon to climate change in CMIP6 Earth system models: the role of false priming
Alkalinity biases in CMIP6 Earth system models and implications for simulated CO2 drawdown via artificial alkalinity enhancement
Experiments of the efficacy of tree ring blue intensity as a climate proxy in central and western China
Burned area and carbon emissions across northwestern boreal North America from 2001–2019
Quantifying land carbon cycle feedbacks under negative CO2 emissions
The potential of an increased deciduous forest fraction to mitigate the effects of heat extremes in Europe
Ideas and perspectives: Alleviation of functional limitations by soil organisms is key to climate feedbacks from arctic soils
A comparison of the climate and carbon cycle effects of carbon removal by afforestation and an equivalent reduction in fossil fuel emissions
Stability of alkalinity in ocean alkalinity enhancement (OAE) approaches – consequences for durability of CO2 storage
Ideas and perspectives: Land–ocean connectivity through groundwater
Bioclimatic change as a function of global warming from CMIP6 climate projections
Reconciling different approaches to quantifying land surface temperature impacts of afforestation using satellite observations
Drivers of intermodel uncertainty in land carbon sink projections
Rebecca Chloe Evans and H. Damon Matthews
Biogeosciences, 22, 1969–1984, https://doi.org/10.5194/bg-22-1969-2025, https://doi.org/10.5194/bg-22-1969-2025, 2025
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To mitigate our impact on the climate, we must both drastically reduce emissions and perform carbon dioxide removal (CDR). We simulated agriculture as a form of CDR under three future climate scenarios to find out how the climate responds to CDR when the carbon is not permanently stored. We found that agricultural CDR is much more effective at reducing global temperatures if done in a low-emissions scenario and at a high rate, and it becomes less effective as removal continues.
Tomohiro Hajima, Michio Kawamiya, Akihiko Ito, Kaoru Tachiiri, Chris D. Jones, Vivek Arora, Victor Brovkin, Roland Séférian, Spencer Liddicoat, Pierre Friedlingstein, and Elena Shevliakova
Biogeosciences, 22, 1447–1473, https://doi.org/10.5194/bg-22-1447-2025, https://doi.org/10.5194/bg-22-1447-2025, 2025
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This study analyzes atmospheric CO2 concentrations and global carbon budgets simulated by multiple Earth system models, using several types of simulations (CO2 concentration- and emission-driven experiments). We successfully identified problems with regard to the global carbon budget in each model. We also found urgent issues with regard to land use change CO2 emissions that should be solved in the latest generation of models.
Nicolas Picard, Noël Fonton, Faustin Boyemba Bosela, Adeline Fayolle, Joël Loumeto, Gabriel Ngua Ayecaba, Bonaventure Sonké, Olga Diane Yongo Bombo, Hervé Martial Maïdou, and Alfred Ngomanda
Biogeosciences, 22, 1413–1426, https://doi.org/10.5194/bg-22-1413-2025, https://doi.org/10.5194/bg-22-1413-2025, 2025
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Allometric equations predict tree biomass and are crucial for estimating forest carbon storage, thus assessing the role of forests in climate change mitigation. Usually, these equations are selected based on tree-level predictive performance. However, we evaluated the model performance at plot and forest levels, finding it varies with plot size. This has significant implications for reducing uncertainty in biomass estimates at these levels.
Mana Gharun, Ankit Shekhar, Lukas Hörtnagl, Luana Krebs, Nicola Arriga, Mirco Migliavacca, Marilyn Roland, Bert Gielen, Leonardo Montagnani, Enrico Tomelleri, Ladislav Šigut, Matthias Peichl, Peng Zhao, Marius Schmidt, Thomas Grünwald, Mika Korkiakoski, Annalea Lohila, and Nina Buchmann
Biogeosciences, 22, 1393–1411, https://doi.org/10.5194/bg-22-1393-2025, https://doi.org/10.5194/bg-22-1393-2025, 2025
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The effect of winter warming on forest CO2 fluxes has rarely been investigated. We tested the effect of the warm winter of 2020 on the forest CO2 fluxes across 14 sites in Europe and found that the net ecosystem productivity (NEP) across most sites declined during the warm winter due to increased respiration fluxes.
Yu Shang, Jingmin Qiu, Yuxi Weng, Xin Wang, Di Zhang, Yuwei Zhou, Juntian Xu, and Futian Li
Biogeosciences, 22, 1203–1214, https://doi.org/10.5194/bg-22-1203-2025, https://doi.org/10.5194/bg-22-1203-2025, 2025
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Research on the influences of dynamic pH on the marine ecosystem is still in its infancy. We manipulated the culturing pH to simulate pH fluctuation and found lower pH could increase eicosapentaenoic acid and docosahexaenoic acid production with unaltered growth and photosynthesis in two marine diatoms. It is important to consider pH variation for more accurate predictions regarding the consequences of acidification in coastal waters.
Anne L. Morée, Fabrice Lacroix, William W. L. Cheung, and Thomas L. Frölicher
Biogeosciences, 22, 1115–1133, https://doi.org/10.5194/bg-22-1115-2025, https://doi.org/10.5194/bg-22-1115-2025, 2025
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Using novel Earth system model simulations and applying the Aerobic Growth Index, we show that only about half of the habitat loss for marine species is realized when temperature stabilization is initially reached. The maximum habitat loss happens over a century after peak warming in a temperature overshoot scenario peaking at 2 °C before stabilizing at 1.5 °C. We also emphasize that species adaptation may be key in mitigating the long-term impacts of temperature stabilization and overshoot.
Jo Cook, Durgesh Singh Yadav, Felicity Hayes, Nathan Booth, Sam Bland, Pritha Pande, Samarthia Thankappan, and Lisa Emberson
Biogeosciences, 22, 1035–1056, https://doi.org/10.5194/bg-22-1035-2025, https://doi.org/10.5194/bg-22-1035-2025, 2025
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Ozone (O3) pollution reduces wheat yields and quality in India, affecting amino acids essential for nutrition, like lysine and methionine. Here, we improve the DO3SE-CropN model to simulate wheat’s protective processes against O3 and their impact on protein and amino acid concentrations. While the model captures O3-induced yield losses, it underestimates amino acid reductions. Further research is needed to refine the model, enabling future risk assessments of O3's impact on yields and nutrition.
Stéphane Doléac, Marina Lévy, Roy El Hourany, and Laurent Bopp
Biogeosciences, 22, 841–862, https://doi.org/10.5194/bg-22-841-2025, https://doi.org/10.5194/bg-22-841-2025, 2025
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The marine biogeochemistry components of Coupled Model Intercomparison Project phase 6 (CMIP6) models vary widely in their process representations. Using an innovative bioregionalization of the North Atlantic, we reveal that this model diversity largely drives the divergence in net primary production projections under a high-emission scenario. The identification of the most mechanistically realistic models allows for a substantial reduction in projection uncertainty.
Nina Bednaršek, Hanna van de Mortel, Greg Pelletier, Marisol García-Reyes, Richard A. Feely, and Andrew G. Dickson
Biogeosciences, 22, 473–498, https://doi.org/10.5194/bg-22-473-2025, https://doi.org/10.5194/bg-22-473-2025, 2025
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The environmental impacts of ocean alkalinity enhancement (OAE) are unknown. Our synthesis, based on 68 collected studies with 84 unique species, shows that 35 % of species respond positively, 26 % respond negatively, and 39 % show a neutral response to alkalinity addition. Biological thresholds were found from 50 to 500 µmol kg−1 NaOH addition. A precautionary approach is warranted to avoid potential risks, while current regulatory framework needs improvements to assure safe biological limits.
Luna J. J. Geerts, Astrid Hylén, and Filip J. R. Meysman
Biogeosciences, 22, 355–384, https://doi.org/10.5194/bg-22-355-2025, https://doi.org/10.5194/bg-22-355-2025, 2025
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Marine enhanced rock weathering (mERW) with olivine is a promising method for capturing CO2 from the atmosphere, yet studies in field conditions are lacking. We bridge the gap between theoretical studies and the real-world environment by estimating the predictability of mERW parameters and identifying aspects to consider when applying mERW. A major source of uncertainty is the lack of experimental studies with sediment, which can heavily influence the speed and efficiency of CO2 drawdown.
Christian Blair Lewis, Rachel Corran, Sara Mikaloff-Fletcher, Erik Behrens, Rowena Moss, Gordon Brailsford, Andrew Lorrey, Margaret Norris, and Jocelyn Turnbull
EGUsphere, https://doi.org/10.5194/egusphere-2024-4107, https://doi.org/10.5194/egusphere-2024-4107, 2025
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The Southern Ocean carbon sink is a balance between two opposing forces: CO2 absorption at mid-latitudes and CO2 outgassing at high-latitudes. Radiocarbon analysis can be used to constrain the latter, as upwelling waters outgas old CO2, diluting atmospheric radiocarbon content. We present tree-ring radiocarbon measurements from New Zealand and Chile. We show that low radiocarbon in New Zealand’s Campbell Island is linked to outgassing in the critical Antarctic Southern Zone.
Philipp Suessle, Jan Taucher, Silvan Urs Goldenberg, Moritz Baumann, Kristian Spilling, Andrea Noche-Ferreira, Mari Vanharanta, and Ulf Riebesell
Biogeosciences, 22, 71–86, https://doi.org/10.5194/bg-22-71-2025, https://doi.org/10.5194/bg-22-71-2025, 2025
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Ocean alkalinity enhancement (OAE) is a negative emission technology which may alter marine communities and the particle export they drive. Here, impacts of carbonate-based OAE on the flux and attenuation of sinking particles in an oligotrophic plankton community are presented. Whilst biological parameters remained unaffected, abiotic carbonate precipitation occurred. Among counteracting OAE’s efficiency, it influenced mineral ballasting and particle sinking velocities, requiring monitoring.
Thuy Huu Nguyen, Thomas Gaiser, Jan Vanderborght, Andrea Schnepf, Felix Bauer, Anja Klotzsche, Lena Lärm, Hubert Hüging, and Frank Ewert
Biogeosciences, 21, 5495–5515, https://doi.org/10.5194/bg-21-5495-2024, https://doi.org/10.5194/bg-21-5495-2024, 2024
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Leaf water potential was at certain thresholds, depending on soil type, water treatment, and weather conditions. In rainfed plots, the lower water availability in the stony soil resulted in fewer roots with a higher root tissue conductance than the silty soil. In the silty soil, higher stress in the rainfed soil led to more roots with a lower root tissue conductance than in the irrigated plot. Crop responses to water stress can be opposite, depending on soil water conditions that are compared.
Mana Gharun, Ankit Shekhar, Jingfeng Xiao, Xing Li, and Nina Buchmann
Biogeosciences, 21, 5481–5494, https://doi.org/10.5194/bg-21-5481-2024, https://doi.org/10.5194/bg-21-5481-2024, 2024
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In 2022, Europe's forests faced unprecedented dry conditions. Our study aimed to understand how different forest types respond to extreme drought. Using meteorological data and satellite imagery, we compared 2022 with two previous extreme years, 2003 and 2018. Despite less severe drought in 2022, forests showed a 30 % greater decline in photosynthesis compared to 2018 and 60 % more than 2003. This suggests an alarming level of vulnerability of forests across Europe to more frequent droughts.
Qi Zheng, Johannes J. Viljoen, Xuerong Sun, and Robert J. W. Brewin
EGUsphere, https://doi.org/10.5194/egusphere-2024-3502, https://doi.org/10.5194/egusphere-2024-3502, 2024
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Phytoplankton contribute to half of Earth’s primary production, but not a lot is known about subsurface phytoplankton, living at the base of the sunlit ocean. We develop a two-layered box model to simulate phytoplankton seasonal and interannual variations in different depth layers of the ocean. Our model captures seasonal and long-term trends of the two layers, explaining how they respond to a warming ocean, furthering our understanding of how phytoplankton are responding to climate change.
Gabriella Everett, Øivind Hodnebrog, Madhoolika Agrawal, Durgesh Singh Yadav, Connie O'Neill, Chubamenla Jamir, Jo Cook, Pritha Pande, and Lisa Emberson
EGUsphere, https://doi.org/10.5194/egusphere-2024-3371, https://doi.org/10.5194/egusphere-2024-3371, 2024
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Ground-level ozone (O3), heat, and water stress (WS) reduce wheat yields, threatening food security in India. O3, heat, and WS interact as stressed plants close stomata, limiting O3 entry and damage. This study models O3 uptake under rainfed (WS) and irrigated conditions for current and future climates. Results show little O3-related yield loss under wWS but higher losses with irrigation. Both climate scenarios increase O3-related losses, highlighting risks to India’s wheat productivity.
Makcim L. De Sisto and Andrew H. MacDougall
Biogeosciences, 21, 4853–4873, https://doi.org/10.5194/bg-21-4853-2024, https://doi.org/10.5194/bg-21-4853-2024, 2024
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The remaining carbon budget (RCB) represents the allowable future CO2 emissions before a temperature target is reached. Understanding the uncertainty in the RCB is critical for effective climate regulation and policy-making. One major source of uncertainty is the representation of the carbon cycle in Earth system models. We assessed how nutrient limitation affects the estimation of the RCB. We found a reduction in the estimated RCB when nutrient limitation is taken into account.
Outi Kinnunen, Leif Backman, Juha Aalto, Tuula Aalto, and Tiina Markkanen
Biogeosciences, 21, 4739–4763, https://doi.org/10.5194/bg-21-4739-2024, https://doi.org/10.5194/bg-21-4739-2024, 2024
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Climate change is expected to increase the risk of forest fires. Ecosystem process model simulations are used to project changes in fire occurrence in Fennoscandia under six climate projections. The findings suggest a longer fire season, more fires, and an increase in burnt area towards the end of the century.
Jo Cook, Clare Brewster, Felicity Hayes, Nathan Booth, Sam Bland, Pritha Pande, Samarthia Thankappan, Håkan Pleijel, and Lisa Emberson
Biogeosciences, 21, 4809–4835, https://doi.org/10.5194/bg-21-4809-2024, https://doi.org/10.5194/bg-21-4809-2024, 2024
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At ground level, the air pollutant ozone (O3) damages wheat yield and quality. We modified the DO3SE-Crop model to simulate O3 effects on wheat quality and identified onset of leaf death as the key process affecting wheat quality upon O3 exposure. This aligns with expectations, as the onset of leaf death aids nutrient transfer from leaves to grains. Breeders should prioritize wheat varieties resistant to protein loss from delayed leaf death, to maintain yield and quality under O3 exposure.
Niels Suitner, Giulia Faucher, Carl Lim, Julieta Schneider, Charly A. Moras, Ulf Riebesell, and Jens Hartmann
Biogeosciences, 21, 4587–4604, https://doi.org/10.5194/bg-21-4587-2024, https://doi.org/10.5194/bg-21-4587-2024, 2024
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Recent studies described the precipitation of carbonates as a result of alkalinity enhancement in seawater, which could adversely affect the carbon sequestration potential of ocean alkalinity enhancement (OAE) approaches. By conducting experiments in natural seawater, this study observed uniform patterns during the triggered runaway carbonate precipitation, which allow the prediction of safe and efficient local application levels of OAE scenarios.
Milagros Rico, Paula Santiago-Díaz, Guillermo Samperio-Ramos, Melchor González-Dávila, and Juana Magdalena Santana-Casiano
Biogeosciences, 21, 4381–4394, https://doi.org/10.5194/bg-21-4381-2024, https://doi.org/10.5194/bg-21-4381-2024, 2024
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Changes in pH generate stress conditions, either because high pH drastically decreases the availability of trace metals such as Fe(II), a restrictive element for primary productivity, or because reactive oxygen species are increased with low pH. The metabolic functions and composition of microalgae can be affected. These modifications in metabolites are potential factors leading to readjustments in phytoplankton community structure and diversity and possible alteration in marine ecosystems.
Christine Kaufhold, Matteo Willeit, Bo Liu, and Andrey Ganopolski
EGUsphere, https://doi.org/10.5194/egusphere-2024-2976, https://doi.org/10.5194/egusphere-2024-2976, 2024
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This study simulates long-term future climate scenarios to examine how long CO2 emissions will persist in the atmosphere. It shows that the effectiveness of carbon removal processes varies with the amount emitted. The removal of CO2 through silicate weathering is faster than previously thought, leading to a quicker reduction over time. The combined behaviour of different carbon cycle processes emphasizes the need to include all of them in models, as to better predict long-term atmospheric CO2.
Anton Lokshin, Daniel Palchan, Elnatan Golan, Ran Erel, Daniele Andronico, and Avner Gross
EGUsphere, https://doi.org/10.5194/egusphere-2024-2531, https://doi.org/10.5194/egusphere-2024-2531, 2024
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Our research explores how chickpea plants can absorb essential nutrients like phosphorus, iron, and nickel directly from dust deposited on their leaves, in addition to uptake through their roots. This process was particularly effective under higher levels of atmospheric CO2, leading to increased plant growth. By using Nd isotopic tools, we traced the nutrients from dust and found that certain leaf traits enhance this uptake. This discovery may become increasingly important as CO2 levels rise.
James A. King, James Weber, Peter Lawrence, Stephanie Roe, Abigail L. S. Swann, and Maria Val Martin
Biogeosciences, 21, 3883–3902, https://doi.org/10.5194/bg-21-3883-2024, https://doi.org/10.5194/bg-21-3883-2024, 2024
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Tackling climate change by adding, restoring, or enhancing forests is gaining global support. However, it is important to investigate the broader implications of this. We used a computer model of the Earth to investigate a future where tree cover expanded as much as possible. We found that some tropical areas were cooler because of trees pumping water into the atmosphere, but this also led to soil and rivers drying. This is important because it might be harder to maintain forests as a result.
Simone Matias Reis, Yadvinder Malhi, Ben Hur Marimon Junior, Beatriz S. Marimon, Huanyuan Zhang-Zheng, Renata Freitag, Cécile A. J. Girardin, Edmar Almeida de Oliveira, Karine da Silva Peixoto, Luciana Januário de Souza, Ediméia Laura Souza da Silva, Eduarda Bernardes Santos, Kamila Parreira da Silva, Maélly Dállet Alves Gonçalves, Cecilia A. L. Dahlsjö, Oliver L. Phillips, and Imma Oliveras Menor
EGUsphere, https://doi.org/10.5194/egusphere-2024-2118, https://doi.org/10.5194/egusphere-2024-2118, 2024
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The 2015–2016 El Niño caused severe droughts in tropical forests, but its impact on the Cerrado, largest savanna, was unclear. Our study tracked the productivity of two key Cerrado vegetation types over five years. Before El Niño, productivity was higher in the transitional forest-savanna, but it dropped sharply during the event. Meanwhile, the savanna showed minor changes. These findings suggest that transitional ecosystems are particularly vulnerable to drought and climate change.
Benoît Pasquier, Mark Holzer, and Matthew A. Chamberlain
Biogeosciences, 21, 3373–3400, https://doi.org/10.5194/bg-21-3373-2024, https://doi.org/10.5194/bg-21-3373-2024, 2024
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How do perpetually slower and warmer oceans sequester carbon? Compared to the preindustrial state, we find that biological productivity declines despite warming-stimulated growth because of a lower nutrient supply from depth. This throttles the biological carbon pump, which still sequesters more carbon because it takes longer to return to the surface. The deep ocean is isolated from the surface, allowing more carbon from the atmosphere to pass through the ocean without contributing to biology.
Matthew A. Chamberlain, Tilo Ziehn, and Rachel M. Law
Biogeosciences, 21, 3053–3073, https://doi.org/10.5194/bg-21-3053-2024, https://doi.org/10.5194/bg-21-3053-2024, 2024
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This paper explores the climate processes that drive increasing global average temperatures in zero-emission commitment (ZEC) simulations despite decreasing atmospheric CO2. ACCESS-ESM1.5 shows the Southern Ocean to continue to warm locally in all ZEC simulations. In ZEC simulations that start after the emission of more than 1000 Pg of carbon, the influence of the Southern Ocean increases the global temperature.
Shuaifeng Song, Xuezhen Zhang, and Xiaodong Yan
Biogeosciences, 21, 2839–2858, https://doi.org/10.5194/bg-21-2839-2024, https://doi.org/10.5194/bg-21-2839-2024, 2024
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We mapped the distribution of future potential afforestation regions based on future high-resolution climate data and climate–vegetation models. After considering the national afforestation policy and climate change, we found that the future potential afforestation region was mainly located around and to the east of the Hu Line. This study provides a dataset for exploring the effects of future afforestation.
Tianfei Xue, Jens Terhaar, A. E. Friederike Prowe, Thomas L. Frölicher, Andreas Oschlies, and Ivy Frenger
Biogeosciences, 21, 2473–2491, https://doi.org/10.5194/bg-21-2473-2024, https://doi.org/10.5194/bg-21-2473-2024, 2024
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Phytoplankton play a crucial role in marine ecosystems. However, climate change's impact on phytoplankton biomass remains uncertain, particularly in the Southern Ocean. In this region, phytoplankton biomass within the water column is likely to remain stable in response to climate change, as supported by models. This stability arises from a shallower mixed layer, favoring phytoplankton growth but also increasing zooplankton grazing due to phytoplankton concentration near the surface.
Kinga Kulesza and Agata Hościło
Biogeosciences, 21, 2509–2527, https://doi.org/10.5194/bg-21-2509-2024, https://doi.org/10.5194/bg-21-2509-2024, 2024
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We present coherence and time lags in spectral response of three vegetation types in the European temperate zone to the influencing meteorological factors and teleconnection indices for the period 2002–2022. Vegetation condition in broadleaved forest, coniferous forest and pastures was measured with MODIS NDVI and EVI, and the coherence between NDVI and EVI and meteorological elements was described using the methods of wavelet coherence and Pearson’s linear correlation with time lag.
Anton Lokshin, Daniel Palchan, and Avner Gross
Biogeosciences, 21, 2355–2365, https://doi.org/10.5194/bg-21-2355-2024, https://doi.org/10.5194/bg-21-2355-2024, 2024
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Ash particles from wildfires are rich in phosphorus (P), a crucial nutrient that constitutes a limiting factor in 43 % of the world's land ecosystems. We hypothesize that wildfire ash could directly contribute to plant nutrition. We find that fire ash application boosts the growth of plants, but the only way plants can uptake P from fire ash is through the foliar uptake pathway and not through the roots. The fertilization impact of fire ash was also maintained under elevated levels of CO2.
Lucia S. Layritz, Konstantin Gregor, Andreas Krause, Stefan Kruse, Ben F. Meyer, Tom A. M. Pugh, and Anja Rammig
EGUsphere, https://doi.org/10.5194/egusphere-2024-1028, https://doi.org/10.5194/egusphere-2024-1028, 2024
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Disturbances (e.g. fire) can change which species grow in a forest, affecting water, carbon, energy flows, and the climate. They are expected to increase with climate change, but it is uncertain by how much. We studied how future climate and disturbances might impact vegetation with a simulation model. Our findings highlight the importance of considering both factors, with future disturbance patterns posing significant uncertainty. More research is needed to understand their future development.
Marcus Breil, Vanessa K. M. Schneider, and Joaquim G. Pinto
Biogeosciences, 21, 811–824, https://doi.org/10.5194/bg-21-811-2024, https://doi.org/10.5194/bg-21-811-2024, 2024
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The general impact of afforestation on the regional climate conditions in Europe during the period 1986–2015 is investigated. For this purpose, a regional climate model simulation is performed, in which afforestation during this period is considered, and results are compared to a simulation in which this is not the case. Results show that afforestation had discernible impacts on the climate change signal in Europe, which may have mitigated the local warming trend, especially in summer in Europe.
Ali Asaadi, Jörg Schwinger, Hanna Lee, Jerry Tjiputra, Vivek Arora, Roland Séférian, Spencer Liddicoat, Tomohiro Hajima, Yeray Santana-Falcón, and Chris D. Jones
Biogeosciences, 21, 411–435, https://doi.org/10.5194/bg-21-411-2024, https://doi.org/10.5194/bg-21-411-2024, 2024
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Carbon cycle feedback metrics are employed to assess phases of positive and negative CO2 emissions. When emissions become negative, we find that the model disagreement in feedback metrics increases more strongly than expected from the assumption that the uncertainties accumulate linearly with time. The geographical patterns of such metrics over land highlight that differences in response between tropical/subtropical and temperate/boreal ecosystems are a major source of model disagreement.
Flora Desmet, Matthias Münnich, and Nicolas Gruber
Biogeosciences, 20, 5151–5175, https://doi.org/10.5194/bg-20-5151-2023, https://doi.org/10.5194/bg-20-5151-2023, 2023
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Ocean acidity extremes in the upper 250 m depth of the northeastern Pacific rapidly increase with atmospheric CO2 rise, which is worrisome for marine organisms that rapidly experience pH levels outside their local environmental conditions. Presented research shows the spatiotemporal heterogeneity in this increase between regions and depths. In particular, the subsurface increase is substantially slowed down by the presence of mesoscale eddies, often not resolved in Earth system models.
Geneviève W. Elsworth, Nicole S. Lovenduski, Kristen M. Krumhardt, Thomas M. Marchitto, and Sarah Schlunegger
Biogeosciences, 20, 4477–4490, https://doi.org/10.5194/bg-20-4477-2023, https://doi.org/10.5194/bg-20-4477-2023, 2023
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Anthropogenic climate change will influence marine phytoplankton over the coming century. Here, we quantify the influence of anthropogenic climate change on marine phytoplankton internal variability using an Earth system model ensemble and identify a decline in global phytoplankton biomass variance with warming. Our results suggest that climate mitigation efforts that account for marine phytoplankton changes should also consider changes in phytoplankton variance driven by anthropogenic warming.
Olivia Haas, Iain Colin Prentice, and Sandy P. Harrison
Biogeosciences, 20, 3981–3995, https://doi.org/10.5194/bg-20-3981-2023, https://doi.org/10.5194/bg-20-3981-2023, 2023
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We quantify the impact of CO2 and climate on global patterns of burnt area, fire size, and intensity under Last Glacial Maximum (LGM) conditions using three climate scenarios. Climate change alone did not produce the observed LGM reduction in burnt area, but low CO2 did through reducing vegetation productivity. Fire intensity was sensitive to CO2 but strongly affected by changes in atmospheric dryness. Low CO2 caused smaller fires; climate had the opposite effect except in the driest scenario.
Rebecca M. Varney, Sarah E. Chadburn, Eleanor J. Burke, Simon Jones, Andy J. Wiltshire, and Peter M. Cox
Biogeosciences, 20, 3767–3790, https://doi.org/10.5194/bg-20-3767-2023, https://doi.org/10.5194/bg-20-3767-2023, 2023
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This study evaluates soil carbon projections during the 21st century in CMIP6 Earth system models. In general, we find a reduced spread of changes in global soil carbon in CMIP6 compared to the previous CMIP5 generation. The reduced CMIP6 spread arises from an emergent relationship between soil carbon changes due to change in plant productivity and soil carbon changes due to changes in turnover time. We show that this relationship is consistent with false priming under transient climate change.
Claudia Hinrichs, Peter Köhler, Christoph Völker, and Judith Hauck
Biogeosciences, 20, 3717–3735, https://doi.org/10.5194/bg-20-3717-2023, https://doi.org/10.5194/bg-20-3717-2023, 2023
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This study evaluated the alkalinity distribution in 14 climate models and found that most models underestimate alkalinity at the surface and overestimate it in the deeper ocean. It highlights the need for better understanding and quantification of processes driving alkalinity distribution and calcium carbonate dissolution and the importance of accounting for biases in model results when evaluating potential ocean alkalinity enhancement experiments.
Yonghong Zheng, Huanfeng Shen, Rory Abernethy, and Rob Wilson
Biogeosciences, 20, 3481–3490, https://doi.org/10.5194/bg-20-3481-2023, https://doi.org/10.5194/bg-20-3481-2023, 2023
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Investigations in central and western China show that tree ring inverted latewood intensity expresses a strong positive relationship with growing-season temperatures, indicating exciting potential for regions south of 30° N that are traditionally not targeted for temperature reconstructions. Earlywood BI also shows good potential to reconstruct hydroclimate parameters in some humid areas and will enhance ring-width-based hydroclimate reconstructions in the future.
Stefano Potter, Sol Cooperdock, Sander Veraverbeke, Xanthe Walker, Michelle C. Mack, Scott J. Goetz, Jennifer Baltzer, Laura Bourgeau-Chavez, Arden Burrell, Catherine Dieleman, Nancy French, Stijn Hantson, Elizabeth E. Hoy, Liza Jenkins, Jill F. Johnstone, Evan S. Kane, Susan M. Natali, James T. Randerson, Merritt R. Turetsky, Ellen Whitman, Elizabeth Wiggins, and Brendan M. Rogers
Biogeosciences, 20, 2785–2804, https://doi.org/10.5194/bg-20-2785-2023, https://doi.org/10.5194/bg-20-2785-2023, 2023
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Here we developed a new burned-area detection algorithm between 2001–2019 across Alaska and Canada at 500 m resolution. We estimate 2.37 Mha burned annually between 2001–2019 over the domain, emitting 79.3 Tg C per year, with a mean combustion rate of 3.13 kg C m−2. We found larger-fire years were generally associated with greater mean combustion. The burned-area and combustion datasets described here can be used for local- to continental-scale applications of boreal fire science.
V. Rachel Chimuka, Claude-Michel Nzotungicimpaye, and Kirsten Zickfeld
Biogeosciences, 20, 2283–2299, https://doi.org/10.5194/bg-20-2283-2023, https://doi.org/10.5194/bg-20-2283-2023, 2023
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We propose a new method to quantify carbon cycle feedbacks under negative CO2 emissions. Our method isolates the lagged carbon cycle response to preceding positive emissions from the response to negative emissions. Our findings suggest that feedback parameters calculated with the novel approach are larger than those calculated with the conventional approach whereby carbon cycle inertia is not corrected for, with implications for the effectiveness of carbon dioxide removal in reducing CO2 levels.
Marcus Breil, Annabell Weber, and Joaquim G. Pinto
Biogeosciences, 20, 2237–2250, https://doi.org/10.5194/bg-20-2237-2023, https://doi.org/10.5194/bg-20-2237-2023, 2023
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A promising strategy for mitigating burdens of heat extremes in Europe is to replace dark coniferous forests with brighter deciduous forests. The consequence of this would be reduced absorption of solar radiation, which should reduce the intensities of heat periods. In this study, we show that deciduous forests have a certain cooling effect on heat period intensities in Europe. However, the magnitude of the temperature reduction is quite small.
Gesche Blume-Werry, Jonatan Klaminder, Eveline J. Krab, and Sylvain Monteux
Biogeosciences, 20, 1979–1990, https://doi.org/10.5194/bg-20-1979-2023, https://doi.org/10.5194/bg-20-1979-2023, 2023
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Northern soils store a lot of carbon. Most research has focused on how this carbon storage is regulated by cold temperatures. However, it is soil organisms, from minute bacteria to large earthworms, that decompose the organic material. Novel soil organisms from further south could increase decomposition rates more than climate change does and lead to carbon losses. We therefore advocate for including soil organisms when predicting the fate of soil functions in warming northern ecosystems.
Koramanghat Unnikrishnan Jayakrishnan and Govindasamy Bala
Biogeosciences, 20, 1863–1877, https://doi.org/10.5194/bg-20-1863-2023, https://doi.org/10.5194/bg-20-1863-2023, 2023
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Afforestation and reducing fossil fuel emissions are two important mitigation strategies to reduce the amount of global warming. Our work shows that reducing fossil fuel emissions is relatively more effective than afforestation for the same amount of carbon removed from the atmosphere. However, understanding of the processes that govern the biophysical effects of afforestation should be improved before considering our results for climate policy.
Jens Hartmann, Niels Suitner, Carl Lim, Julieta Schneider, Laura Marín-Samper, Javier Arístegui, Phil Renforth, Jan Taucher, and Ulf Riebesell
Biogeosciences, 20, 781–802, https://doi.org/10.5194/bg-20-781-2023, https://doi.org/10.5194/bg-20-781-2023, 2023
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CO2 can be stored in the ocean via increasing alkalinity of ocean water. Alkalinity can be created via dissolution of alkaline materials, like limestone or soda. Presented research studies boundaries for increasing alkalinity in seawater. The best way to increase alkalinity was found using an equilibrated solution, for example as produced from reactors. Adding particles for dissolution into seawater on the other hand produces the risk of losing alkalinity and degassing of CO2 to the atmosphere.
Damian L. Arévalo-Martínez, Amir Haroon, Hermann W. Bange, Ercan Erkul, Marion Jegen, Nils Moosdorf, Jens Schneider von Deimling, Christian Berndt, Michael Ernst Böttcher, Jasper Hoffmann, Volker Liebetrau, Ulf Mallast, Gudrun Massmann, Aaron Micallef, Holly A. Michael, Hendrik Paasche, Wolfgang Rabbel, Isaac Santos, Jan Scholten, Katrin Schwalenberg, Beata Szymczycha, Ariel T. Thomas, Joonas J. Virtasalo, Hannelore Waska, and Bradley A. Weymer
Biogeosciences, 20, 647–662, https://doi.org/10.5194/bg-20-647-2023, https://doi.org/10.5194/bg-20-647-2023, 2023
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Groundwater flows at the land–ocean transition and the extent of freshened groundwater below the seafloor are increasingly relevant in marine sciences, both because they are a highly uncertain term of biogeochemical budgets and due to the emerging interest in the latter as a resource. Here, we discuss our perspectives on future research directions to better understand land–ocean connectivity through groundwater and its potential responses to natural and human-induced environmental changes.
Morgan Sparey, Peter Cox, and Mark S. Williamson
Biogeosciences, 20, 451–488, https://doi.org/10.5194/bg-20-451-2023, https://doi.org/10.5194/bg-20-451-2023, 2023
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Accurate climate models are vital for mitigating climate change; however, projections often disagree. Using Köppen–Geiger bioclimate classifications we show that CMIP6 climate models agree well on the fraction of global land surface that will change classification per degree of global warming. We find that 13 % of land will change climate per degree of warming from 1 to 3 K; thus, stabilising warming at 1.5 rather than 2 K would save over 7.5 million square kilometres from bioclimatic change.
Huanhuan Wang, Chao Yue, and Sebastiaan Luyssaert
Biogeosciences, 20, 75–92, https://doi.org/10.5194/bg-20-75-2023, https://doi.org/10.5194/bg-20-75-2023, 2023
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This study provided a synthesis of three influential methods to quantify afforestation impact on surface temperature. Results showed that actual effect following afforestation was highly dependent on afforestation fraction. When full afforestation is assumed, the actual effect approaches the potential effect. We provided evidence the afforestation faction is a key factor in reconciling different methods and emphasized that it should be considered for surface cooling impacts in policy evaluation.
Ryan S. Padrón, Lukas Gudmundsson, Laibao Liu, Vincent Humphrey, and Sonia I. Seneviratne
Biogeosciences, 19, 5435–5448, https://doi.org/10.5194/bg-19-5435-2022, https://doi.org/10.5194/bg-19-5435-2022, 2022
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The answer to how much carbon land ecosystems are projected to remove from the atmosphere until 2100 is different for each Earth system model. We find that differences across models are primarily explained by the annual land carbon sink dependence on temperature and soil moisture, followed by the dependence on CO2 air concentration, and by average climate conditions. Our insights on why each model projects a relatively high or low land carbon sink can help to reduce the underlying uncertainty.
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