Articles | Volume 18, issue 16
26 Aug 2021
Research article | 26 Aug 2021
Cushion bog plant community responses to passive warming in southern Patagonia
Verónica Pancotto et al.
No articles found.
Zoé Rehder, Thomas Kleinen, Lars Kutzbach, Victor Stepanenko, Moritz Langer, and Victor Brovkin
Preprint under review for BGShort summary
We use a new model to investigate how methane emissions from Arctic ponds change with warming. We fine that emissions increase substantially. Under annual temperatures 5 °C above present temperatures pond methane emissions are more than three times higher than now. Most of this increase is caused by an increase in plant productivity as plant provide the substrate microbes use to produce methane. We conclude that vegetation changes need to be included in predictions of pond methane emissions.
Lutz Beckebanze, Benjamin R. K. Runkle, Josefine Walz, Christian Wille, David Holl, Manuel Helbig, Julia Boike, Torsten Sachs, and Lars Kutzbach
Biogeosciences, 19, 3863–3876,Short summary
In this study, we present observations of lateral and vertical carbon fluxes from a permafrost-affected study site in the Russian Arctic. From this dataset we estimate the net ecosystem carbon balance for this study site. We show that lateral carbon export has a low impact on the net ecosystem carbon balance during the complete study period (3 months). Nevertheless, our results also show that lateral carbon export can exceed vertical carbon uptake at the beginning of the growing season.
Elodie Salmon, Fabrice Jégou, Bertrand Guenet, Line Jourdain, Chunjing Qiu, Vladislav Bastrikov, Christophe Guimbaud, Dan Zhu, Philippe Ciais, Philippe Peylin, Sébastien Gogo, Fatima Laggoun-Défarge, Mika Aurela, M. Syndonia Bret-Harte, Jiquan Chen, Bogdan H. Chojnicki, Housen Chu, Colin W. Edgar, Eugenie S. Euskirchen, Lawrence B. Flanagan, Krzysztof Fortuniak, David Holl, Janina Klatt, Olaf Kolle, Natalia Kowalska, Lars Kutzbach, Annalea Lohila, Lutz Merbold, Włodzimierz Pawlak, Torsten Sachs, and Klaudia Ziemblińska
Geosci. Model Dev., 15, 2813–2838,Short summary
A methane model that features methane production and transport by plants, the ebullition process and diffusion in soil, oxidation to CO2, and CH4 fluxes to the atmosphere has been embedded in the ORCHIDEE-PEAT land surface model, which includes an explicit representation of northern peatlands. This model, ORCHIDEE-PCH4, was calibrated and evaluated on 14 peatland sites. Results show that the model is sensitive to temperature and substrate availability over the top 75 cm of soil depth.
Lutz Beckebanze, Zoé Rehder, David Holl, Christian Wille, Charlotta Mirbach, and Lars Kutzbach
Biogeosciences, 19, 1225–1244,Short summary
Arctic permafrost landscapes feature many water bodies. In contrast to the terrestrial parts of the landscape, the water bodies release carbon to the atmosphere. We compare carbon dioxide and methane fluxes from small water bodies to the surrounding tundra and find not accounting for the carbon dioxide emissions leads to an overestimation of the tundra uptake by 11 %. Consequently, changes in hydrology and water body distribution may substantially impact the overall carbon budget of the Arctic.
Anna-Maria Virkkala, Susan M. Natali, Brendan M. Rogers, Jennifer D. Watts, Kathleen Savage, Sara June Connon, Marguerite Mauritz, Edward A. G. Schuur, Darcy Peter, Christina Minions, Julia Nojeim, Roisin Commane, Craig A. Emmerton, Mathias Goeckede, Manuel Helbig, David Holl, Hiroki Iwata, Hideki Kobayashi, Pasi Kolari, Efrén López-Blanco, Maija E. Marushchak, Mikhail Mastepanov, Lutz Merbold, Frans-Jan W. Parmentier, Matthias Peichl, Torsten Sachs, Oliver Sonnentag, Masahito Ueyama, Carolina Voigt, Mika Aurela, Julia Boike, Gerardo Celis, Namyi Chae, Torben R. Christensen, M. Syndonia Bret-Harte, Sigrid Dengel, Han Dolman, Colin W. Edgar, Bo Elberling, Eugenie Euskirchen, Achim Grelle, Juha Hatakka, Elyn Humphreys, Järvi Järveoja, Ayumi Kotani, Lars Kutzbach, Tuomas Laurila, Annalea Lohila, Ivan Mammarella, Yojiro Matsuura, Gesa Meyer, Mats B. Nilsson, Steven F. Oberbauer, Sang-Jong Park, Roman Petrov, Anatoly S. Prokushkin, Christopher Schulze, Vincent L. St. Louis, Eeva-Stiina Tuittila, Juha-Pekka Tuovinen, William Quinton, Andrej Varlagin, Donatella Zona, and Viacheslav I. Zyryanov
Earth Syst. Sci. Data, 14, 179–208,Short summary
The effects of climate warming on carbon cycling across the Arctic–boreal zone (ABZ) remain poorly understood due to the relatively limited distribution of ABZ flux sites. Fortunately, this flux network is constantly increasing, but new measurements are published in various platforms, making it challenging to understand the ABZ carbon cycle as a whole. Here, we compiled a new database of Arctic–boreal CO2 fluxes to help facilitate large-scale assessments of the ABZ carbon cycle.
Zoé Rehder, Anne Laura Niederdrenk, Lars Kaleschke, and Lars Kutzbach
The Cryosphere, 14, 4201–4215,Short summary
To better understand the connection between sea ice and permafrost, we investigate how sea ice interacts with the atmosphere over the adjacent landmass in the Laptev Sea region using a climate model. Melt of sea ice in spring is mainly controlled by the atmosphere; in fall, feedback mechanisms are important. Throughout summer, lower-than-usual sea ice leads to more southward transport of heat and moisture, but these links from sea ice to the atmosphere over land are weak.
David Holl, Eva-Maria Pfeiffer, and Lars Kutzbach
Biogeosciences, 17, 2853–2874,Short summary
We measured greenhouse gas (GHG) fluxes at a bog site in northwestern Germany that has been heavily degraded by peat mining. During the 2-year investigation period, half of the area was still being mined, whereas the remaining half had been rewetted shortly before. We could therefore estimate the impact of rewetting on GHG flux dynamics. Rewetting had a considerable effect on the annual GHG balance and led to increased (up to 84 %) methane and decreased (up to 40 %) carbon dioxide release.
David Holl, Verónica Pancotto, Adrian Heger, Sergio Jose Camargo, and Lars Kutzbach
Biogeosciences, 16, 3397–3423,Short summary
We present 2 years of eddy covariance carbon dioxide flux data from two Southern Hemisphere peatlands on Tierra del Fuego. One of the investigated sites is a type of bog exclusive to the Southern Hemisphere, which is dominated by vascular, cushion-forming plants and is particularly understudied. One result of this study is that these cushion bogs apparently are highly productive in comparison to Northern and Southern Hemisphere moss-dominated bogs.
Olli Peltola, Timo Vesala, Yao Gao, Olle Räty, Pavel Alekseychik, Mika Aurela, Bogdan Chojnicki, Ankur R. Desai, Albertus J. Dolman, Eugenie S. Euskirchen, Thomas Friborg, Mathias Göckede, Manuel Helbig, Elyn Humphreys, Robert B. Jackson, Georg Jocher, Fortunat Joos, Janina Klatt, Sara H. Knox, Natalia Kowalska, Lars Kutzbach, Sebastian Lienert, Annalea Lohila, Ivan Mammarella, Daniel F. Nadeau, Mats B. Nilsson, Walter C. Oechel, Matthias Peichl, Thomas Pypker, William Quinton, Janne Rinne, Torsten Sachs, Mateusz Samson, Hans Peter Schmid, Oliver Sonnentag, Christian Wille, Donatella Zona, and Tuula Aalto
Earth Syst. Sci. Data, 11, 1263–1289,Short summary
Here we develop a monthly gridded dataset of northern (> 45 N) wetland methane (CH4) emissions. The data product is derived using a random forest machine-learning technique and eddy covariance CH4 fluxes from 25 wetland sites. Annual CH4 emissions from these wetlands calculated from the derived data product are comparable to prior studies focusing on these areas. This product is an independent estimate of northern wetland CH4 emissions and hence could be used, e.g. for process model evaluation.
Norman Rößger, Christian Wille, David Holl, Mathias Göckede, and Lars Kutzbach
Biogeosciences, 16, 2591–2615,
Tim Eckhardt, Christian Knoblauch, Lars Kutzbach, David Holl, Gillian Simpson, Evgeny Abakumov, and Eva-Maria Pfeiffer
Biogeosciences, 16, 1543–1562,Short summary
We quantified the contribution of individual components governing the net ecosystem exchange of CO2 and how these fluxes respond to environmental changes in a drained and water-saturated site in the polygonal tundra of northeast Siberia. This work finds both sites as a sink for atmospheric CO2 during the growing season, but sink strengths varied between the sites. Furthermore, it was shown that soil hydrological conditions were one of the key drivers for differing CO2 fluxes between the sites.
Julia Boike, Jan Nitzbon, Katharina Anders, Mikhail Grigoriev, Dmitry Bolshiyanov, Moritz Langer, Stephan Lange, Niko Bornemann, Anne Morgenstern, Peter Schreiber, Christian Wille, Sarah Chadburn, Isabelle Gouttevin, Eleanor Burke, and Lars Kutzbach
Earth Syst. Sci. Data, 11, 261–299,Short summary
Long-term observational data are available from the Samoylov research site in northern Siberia, where meteorological parameters, energy balance, and subsurface observations have been recorded since 1998. This paper presents the temporal data set produced between 2002 and 2017, explaining the instrumentation, calibration, processing, and data quality control. Furthermore, we present a merged dataset of the parameters, which were measured from 1998 onwards.
David Holl, Christian Wille, Torsten Sachs, Peter Schreiber, Benjamin R. K. Runkle, Lutz Beckebanze, Moritz Langer, Julia Boike, Eva-Maria Pfeiffer, Irina Fedorova, Dimitry Y. Bolshianov, Mikhail N. Grigoriev, and Lars Kutzbach
Earth Syst. Sci. Data, 11, 221–240,Short summary
We present a multi-annual time series of land–atmosphere carbon dioxide fluxes measured in situ with the eddy covariance technique in the Siberian Arctic. In arctic permafrost regions, climate–carbon feedbacks are amplified. Therefore, increased efforts to better represent these regions in global climate models have been made in recent years. Up to now, the available database of in situ measurements from the Arctic was biased towards Alaska and records from the Eurasian Arctic were scarce.
Chunjing Qiu, Dan Zhu, Philippe Ciais, Bertrand Guenet, Gerhard Krinner, Shushi Peng, Mika Aurela, Christian Bernhofer, Christian Brümmer, Syndonia Bret-Harte, Housen Chu, Jiquan Chen, Ankur R. Desai, Jiří Dušek, Eugénie S. Euskirchen, Krzysztof Fortuniak, Lawrence B. Flanagan, Thomas Friborg, Mateusz Grygoruk, Sébastien Gogo, Thomas Grünwald, Birger U. Hansen, David Holl, Elyn Humphreys, Miriam Hurkuck, Gerard Kiely, Janina Klatt, Lars Kutzbach, Chloé Largeron, Fatima Laggoun-Défarge, Magnus Lund, Peter M. Lafleur, Xuefei Li, Ivan Mammarella, Lutz Merbold, Mats B. Nilsson, Janusz Olejnik, Mikaell Ottosson-Löfvenius, Walter Oechel, Frans-Jan W. Parmentier, Matthias Peichl, Norbert Pirk, Olli Peltola, Włodzimierz Pawlak, Daniel Rasse, Janne Rinne, Gaius Shaver, Hans Peter Schmid, Matteo Sottocornola, Rainer Steinbrecher, Torsten Sachs, Marek Urbaniak, Donatella Zona, and Klaudia Ziemblinska
Geosci. Model Dev., 11, 497–519,Short summary
Northern peatlands store large amount of soil carbon and are vulnerable to climate change. We implemented peatland hydrological and carbon accumulation processes into the ORCHIDEE land surface model. The model was evaluated against EC measurements from 30 northern peatland sites. The model generally well reproduced the spatial gradient and temporal variations in GPP and NEE at these sites. Water table depth was not well predicted but had only small influence on simulated NEE.
Sarah E. Chadburn, Gerhard Krinner, Philipp Porada, Annett Bartsch, Christian Beer, Luca Belelli Marchesini, Julia Boike, Altug Ekici, Bo Elberling, Thomas Friborg, Gustaf Hugelius, Margareta Johansson, Peter Kuhry, Lars Kutzbach, Moritz Langer, Magnus Lund, Frans-Jan W. Parmentier, Shushi Peng, Ko Van Huissteden, Tao Wang, Sebastian Westermann, Dan Zhu, and Eleanor J. Burke
Biogeosciences, 14, 5143–5169,Short summary
Earth system models (ESMs) are our main tools for understanding future climate. The Arctic is important for the future carbon cycle, particularly due to the large carbon stocks in permafrost. We evaluated the performance of the land component of three major ESMs at Arctic tundra sites, focusing on the fluxes and stocks of carbon. We show that the next steps for model improvement are to better represent vegetation dynamics, to include mosses and to improve below-ground carbon cycle processes.
Fabian Beermann, Moritz Langer, Sebastian Wetterich, Jens Strauss, Julia Boike, Claudia Fiencke, Lutz Schirrmeister, Eva-Maria Pfeiffer, and Lars Kutzbach
Revised manuscript not acceptedShort summary
This paper aims to quantify pools of inorganic nitrogen in permafrost soils of arctic Siberia and to estimate annual release rates of this nitrogen due to permafrost thaw. We report for the first time stores of inorganic nitrogen in Siberian permafrost soils. These nitrogen stores are important as permafrost thaw can mobilize substantial amounts of nitrogen, potentially changing the nutrient balance of these soils and representing a significant non-carbon permafrost climate feedback.
F. Cresto Aleina, B. R. K. Runkle, T. Kleinen, L. Kutzbach, J. Schneider, and V. Brovkin
Biogeosciences, 12, 5689–5704,Short summary
We developed a process-based model for peatland micro-topography and hydrology, the Hummock-Hollow (HH) model, which explicitly represents small-scale surface elevation changes. By coupling the HH model with a model for soil methane processes, we are able to model the effects of micro-topography on hydrology and methane emissions in a typical boreal peatland. We also identify potential biases that models without a micro-topographic representation can introduce in large-scale models.
M. Vanselow-Algan, S. R. Schmidt, M. Greven, C. Fiencke, L. Kutzbach, and E.-M. Pfeiffer
Biogeosciences, 12, 4361–4371,
Related subject area
Earth System Science/Response to Global Change: Climate ChangeBioclimatic change as a function of global warming from CMIP6 climate projectionsReconciling different approaches to quantifying land surface temperature impacts of afforestation using satellite observationsDrivers of intermodel uncertainty in land carbon sink projectionsReviews and syntheses: A framework to observe, understand and project ecosystem response to environmental change in the East Antarctic Southern OceanAcidification impacts and acclimation potential of Caribbean benthic foraminifera assemblages in naturally discharging low-pH waterMonitoring vegetation condition using microwave remote sensing: the standardized vegetation optical depth index (SVODI)Evaluation of soil carbon simulation in CMIP6 Earth system modelsDiazotrophy as a key driver of the response of marine net primary productivity to climate changeImpact of negative and positive CO2 emissions on global warming metrics using an ensemble of Earth system model simulationsAcidification, deoxygenation, and nutrient and biomass declines in a warming Mediterranean SeaOcean alkalinity enhancement – avoiding runaway CaCO3 precipitation during quick and hydrated lime dissolutionAssessment of the impacts of biological nitrogen fixation structural uncertainty in CMIP6 earth system modelsSoil carbon loss in warmed subarctic grasslands is rapid and restricted to topsoilThe European forest carbon budget under future climate conditions and current management practicesIdeas and perspectives: Land-ocean connectivity through groundwaterThe influence of mesoscale climate drivers on hypoxia in a fjord-like deep coastal inlet and its potential implications regarding climate change: examining a decade of water quality dataContrasting responses of phytoplankton productivity between coastal and offshore surface waters in the Taiwan Strait and the South China Sea to short-term seawater acidificationStability of alkalinity in Ocean Alkalinity Enhancement (OAE) approaches – consequences for durability of CO2 storageModeling interactions between tides, storm surges, and river discharges in the Kapuas River deltaThe application of dendrometers to alpine dwarf shrubs – a case study to investigate stem growth responses to environmental conditionsClimate, land cover and topography: essential ingredients in predicting wetland permanenceNot all biodiversity rich spots are climate refugiaEvaluating the dendroclimatological potential of blue intensity on multiple conifer species from Tasmania and New ZealandAnthropogenic CO2-mediated freshwater acidification limits survival, calcification, metabolism, and behaviour in stress-tolerant freshwater crustaceansQuantifying the role of moss in terrestrial ecosystem carbon dynamics in northern high latitudesOn the influence of erect shrubs on the irradiance profile in snowTolerance of tropical marine microphytobenthos exposed to elevated irradiance and temperaturePersistent impacts of the 2018 drought on forest disturbance regimes in EuropeReviews and syntheses: Arctic fire regimes and emissions in the 21st centurySlowdown of the greening trend in natural vegetation with further rise in atmospheric CO2Effects of elevated CO2 and extreme climatic events on forage quality and in vitro rumen fermentation in permanent grasslandBlue carbon stocks and exchanges along the California coastOceanic primary production decline halved in eddy-resolving simulations of global warmingAssessing climate change impacts on live fuel moisture and wildfire risk using a hydrodynamic vegetation modelDoes drought advance the onset of autumn leaf senescence in temperate deciduous forest trees?Ocean carbon cycle feedbacks in CMIP6 models: contributions from different basinsSensitivity of 21st-century projected ocean new production changes to idealized biogeochemical model structureOcean carbon uptake under aggressive emission mitigationEffects of Earth system feedbacks on the potential mitigation of large-scale tropical forest restorationWetter environment and increased grazing reduced the area burned in northern Eurasia from 2002 to 2016Physiological responses of Skeletonema costatum to the interactions of seawater acidification and the combination of photoperiod and temperatureTechnical note: Interpreting pH changesTiming of drought in the growing season and strong legacy effects determine the annual productivity of temperate grasses in a changing climateContrasting responses of woody and herbaceous vegetation to altered rainfall characteristics in the SahelReduced growth with increased quotas of particulate organic and inorganic carbon in the coccolithophore Emiliania huxleyi under future ocean climate change conditionsOcean-related global change alters lipid biomarker production in common marine phytoplanktonMulti-decadal changes in structural complexity following mass coral mortality on a Caribbean reefStable isotopes track the ecological and biogeochemical legacy of mass mangrove forest dieback in the Gulf of Carpentaria, AustraliaGlobal climate response to idealized deforestation in CMIP6 modelsCarbon–concentration and carbon–climate feedbacks in CMIP6 models and their comparison to CMIP5 models
Morgan Sparey, Peter Cox, and Mark S. Williamson
Biogeosciences, 20, 451–488,Short summary
Accurate climate models are vital for mitigating climate change; however, projections often disagree. Using Köppen–Geiger bioclimate classifications we show that CMIP6 climate models agree well on the fraction of global land surface that will change classification per degree of global warming. We find that 13 % of land will change climate per degree of warming from 1 to 3 K; thus, stabilising warming at 1.5 rather than 2 K would save over 7.5 million square kilometres from bioclimatic change.
Huanhuan Wang, Chao Yue, and Sebastiaan Luyssaert
Biogeosciences, 20, 75–92,Short summary
This study provided a synthesis of three influential methods to quantify afforestation impact on surface temperature. Results showed that actual effect following afforestation was highly dependent on afforestation fraction. When full afforestation is assumed, the actual effect approaches the potential effect. We provided evidence the afforestation faction is a key factor in reconciling different methods and emphasized that it should be considered for surface cooling impacts in policy evaluation.
Ryan S. Padrón, Lukas Gudmundsson, Laibao Liu, Vincent Humphrey, and Sonia I. Seneviratne
Biogeosciences, 19, 5435–5448,Short summary
The answer to how much carbon land ecosystems are projected to remove from the atmosphere until 2100 is different for each Earth system model. We find that differences across models are primarily explained by the annual land carbon sink dependence on temperature and soil moisture, followed by the dependence on CO2 air concentration, and by average climate conditions. Our insights on why each model projects a relatively high or low land carbon sink can help to reduce the underlying uncertainty.
Julian Gutt, Stefanie Arndt, David Keith Alan Barnes, Horst Bornemann, Thomas Brey, Olaf Eisen, Hauke Flores, Huw Griffiths, Christian Haas, Stefan Hain, Tore Hattermann, Christoph Held, Mario Hoppema, Enrique Isla, Markus Janout, Céline Le Bohec, Heike Link, Felix Christopher Mark, Sebastien Moreau, Scarlett Trimborn, Ilse van Opzeeland, Hans-Otto Pörtner, Fokje Schaafsma, Katharina Teschke, Sandra Tippenhauer, Anton Van de Putte, Mia Wege, Daniel Zitterbart, and Dieter Piepenburg
Biogeosciences, 19, 5313–5342,Short summary
Long-term ecological observations are key to assess, understand and predict impacts of environmental change on biotas. We present a multidisciplinary framework for such largely lacking investigations in the East Antarctic Southern Ocean, combined with case studies, experimental and modelling work. As climate change is still minor here but is projected to start soon, the timely implementation of this framework provides the unique opportunity to document its ecological impacts from the very onset.
Daniel François, Adina Paytan, Olga Maria Oliveira de Araújo, Ricardo Tadeu Lopes, and Cátia Fernandes Barbosa
Biogeosciences, 19, 5269–5285,Short summary
Our analysis revealed that under the two most conservative acidification projections foraminifera assemblages did not display considerable changes. However, a significant decrease in species richness was observed when pH decreases to 7.7 pH units, indicating adverse effects under high-acidification scenarios. A micro-CT analysis revealed that calcified tests of Archaias angulatus were of lower density in low pH, suggesting no acclimation capacity for this species.
Leander Moesinger, Ruxandra-Maria Zotta, Robin van der Schalie, Tracy Scanlon, Richard de Jeu, and Wouter Dorigo
Biogeosciences, 19, 5107–5123,Short summary
The standardized vegetation optical depth index (SVODI) can be used to monitor the vegetation condition, such as whether the vegetation is unusually dry or wet. SVODI has global coverage, spans the past 3 decades and is derived from multiple spaceborne passive microwave sensors of that period. SVODI is based on a new probabilistic merging method that allows the merging of normally distributed data even if the data are not gap-free.
Rebecca M. Varney, Sarah E. Chadburn, Eleanor J. Burke, and Peter M. Cox
Biogeosciences, 19, 4671–4704,Short summary
Soil carbon is the Earth’s largest terrestrial carbon store, and the response to climate change represents one of the key uncertainties in obtaining accurate global carbon budgets required to successfully militate against climate change. The ability of climate models to simulate present-day soil carbon is therefore vital. This study assesses soil carbon simulation in the latest ensemble of models which allows key areas for future model development to be identified.
Laurent Bopp, Olivier Aumont, Lester Kwiatkowski, Corentin Clerc, Léonard Dupont, Christian Ethé, Thomas Gorgues, Roland Séférian, and Alessandro Tagliabue
Biogeosciences, 19, 4267–4285,Short summary
The impact of anthropogenic climate change on the biological production of phytoplankton in the ocean is a cause for concern because its evolution could affect the response of marine ecosystems to climate change. Here, we identify biological N fixation and its response to future climate change as a key process in shaping the future evolution of marine phytoplankton production. Our results show that further study of how this nitrogen fixation responds to environmental change is essential.
Negar Vakilifard, Richard G. Williams, Philip B. Holden, Katherine Turner, Neil R. Edwards, and David J. Beerling
Biogeosciences, 19, 4249–4265,Short summary
To remain within the Paris climate agreement, there is an increasing need to develop and implement carbon capture and sequestration techniques. The global climate benefits of implementing negative emission technologies over the next century are assessed using an Earth system model covering a wide range of plausible climate states. In some model realisations, there is continued warming after emissions cease. This continued warming is avoided if negative emissions are incorporated.
Marco Reale, Gianpiero Cossarini, Paolo Lazzari, Tomas Lovato, Giorgio Bolzon, Simona Masina, Cosimo Solidoro, and Stefano Salon
Biogeosciences, 19, 4035–4065,Short summary
Future projections under the RCP8.5 and RCP4.5 emission scenarios of the Mediterranean Sea biogeochemistry at the end of the 21st century show different levels of decline in nutrients, oxygen and biomasses and an acidification of the water column. The signal intensity is stronger under RCP8.5 and in the eastern Mediterranean. Under RCP4.5, after the second half of the 21st century, biogeochemical variables show a recovery of the values observed at the beginning of the investigated period.
Charly A. Moras, Lennart T. Bach, Tyler Cyronak, Renaud Joannes-Boyau, and Kai G. Schulz
Biogeosciences, 19, 3537–3557,Short summary
This research presents the first laboratory results of quick and hydrated lime dissolution in natural seawater. These two minerals are of great interest for ocean alkalinity enhancement, a strategy aiming to decrease atmospheric CO2 concentrations. Following the dissolution of these minerals, we identified several hurdles and presented ways to avoid them or completely negate them. Finally, we proceeded to various simulations in today’s oceans to implement the strategy at its highest potential.
Taraka Davies-Barnard, Sönke Zaehle, and Pierre Friedlingstein
Biogeosciences, 19, 3491–3503,Short summary
Biological nitrogen fixation is the largest natural input of new nitrogen onto land. Earth system models mainly represent global total terrestrial biological nitrogen fixation within observational uncertainties but overestimate tropical fixation. The model range of increase in biological nitrogen fixation in the SSP3-7.0 scenario is 3 % to 87 %. While biological nitrogen fixation is a key source of new nitrogen, its predictive power for net primary productivity in models is limited.
Niel Verbrigghe, Niki I. W. Leblans, Bjarni D. Sigurdsson, Sara Vicca, Chao Fang, Lucia Fuchslueger, Jennifer L. Soong, James T. Weedon, Christopher Poeplau, Cristina Ariza-Carricondo, Michael Bahn, Bertrand Guenet, Per Gundersen, Gunnhildur E. Gunnarsdóttir, Thomas Kätterer, Zhanfeng Liu, Marja Maljanen, Sara Marañón-Jiménez, Kathiravan Meeran, Edda S. Oddsdóttir, Ivika Ostonen, Josep Peñuelas, Andreas Richter, Jordi Sardans, Páll Sigurðsson, Margaret S. Torn, Peter M. Van Bodegom, Erik Verbruggen, Tom W. N. Walker, Håkan Wallander, and Ivan A. Janssens
Biogeosciences, 19, 3381–3393,Short summary
In subarctic grassland on a geothermal warming gradient, we found large reductions in topsoil carbon stocks, with carbon stocks linearly declining with warming intensity. Most importantly, however, we observed that soil carbon stocks stabilised within 5 years of warming and remained unaffected by warming thereafter, even after > 50 years of warming. Moreover, in contrast to the large topsoil carbon losses, subsoil carbon stocks remained unaffected after > 50 years of soil warming.
Roberto Pilli, Ramdane Alkama, Alessandro Cescatti, Werner A. Kurz, and Giacomo Grassi
Biogeosciences, 19, 3263–3284,Short summary
To become carbon neutral by 2050, the European Union (EU27) forest C sink should increase to −450 Mt CO2 yr-1. Our study highlights that under current management practices (i.e. excluding any policy scenario) the forest C sink of the EU27 member states and the UK may decrease to about −250 Mt CO2eq yr-1 in 2050. The expected impacts of future climate change, however, add a considerable uncertainty, potentially nearly doubling or halving the sink associated with forest management.
Damian Leonardo Arévalo-Martínez, Amir Haroon, Hermann Werner 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 Weymer
Revised manuscript accepted for BGShort summary
Groundwater flows at the land-ocean transition and the extent of freshened groundwater below the seafloor are increasingly relevant in marine sciences both because they are a highly uncertain term of biogeochemical budgets, and also 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.
Johnathan Daniel Maxey, Neil David Hartstein, Aazani Mujahid, and Moritz Müller
Biogeosciences, 19, 3131–3150,Short summary
Deep coastal inlets are important sites for regulating land-based organic pollution before it enters coastal oceans. This study focused on how large climate forces, rainfall, and river flow impact organic loading and oxygen conditions in a coastal inlet in Tasmania. Increases in rainfall were linked to higher organic loading and lower oxygen in basin waters. Finally we observed a significant correlation between the Southern Annular Mode and oxygen concentrations in the system's basin waters.
Guang Gao, Tifeng Wang, Jiazhen Sun, Xin Zhao, Lifang Wang, Xianghui Guo, and Kunshan Gao
Biogeosciences, 19, 2795–2804,Short summary
After conducting large-scale deck-incubation experiments, we found that seawater acidification (SA) increased primary production (PP) in coastal waters but reduced it in pelagic zones, which is mainly regulated by local pH, light intensity, salinity, and community structure. In future oceans, SA combined with decreased upward transports of nutrients may synergistically reduce PP in pelagic zones.
Jens Hartmann, Niels Suitner, Carl Lim, Julieta Schneider, Laura Marín-Samper, Javier Arístegui, Phil Renforth, Jan Taucher, and Ulf Riebesell
Revised manuscript accepted for BGShort summary
CO2 can be stored in the ocean via increasing alkalinity of ocean water. Alkalinity is 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, as for example 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.
Joko Sampurno, Valentin Vallaeys, Randy Ardianto, and Emmanuel Hanert
Biogeosciences, 19, 2741–2757,Short summary
This study is the first assessment to evaluate the interactions between river discharges, tides, and storm surges and how they can drive compound flooding in the Kapuas River delta. We successfully created a realistic hydrodynamic model whose domain covers the land–sea continuum using a wetting–drying algorithm in a data-scarce environment. We then proposed a new method to delineate compound flooding hazard zones along the river channels based on the maximum water level profiles.
Svenja Dobbert, Roland Pape, and Jörg Löffler
Biogeosciences, 19, 1933–1958,Short summary
Understanding how vegetation might respond to climate change is especially important in arctic–alpine ecosystems, where major shifts in shrub growth have been observed. We studied how such changes come to pass and how future changes might look by measuring hourly variations in the stem diameter of dwarf shrubs from one common species. From these data, we are able to discern information about growth mechanisms and can thus show the complexity of shrub growth and micro-environment relations.
Jody Daniel, Rebecca C. Rooney, and Derek T. Robinson
Biogeosciences, 19, 1547–1570,Short summary
The threat posed by climate change to prairie pothole wetlands is well documented, but gaps remain in our ability to make meaningful predictions about how prairie pothole wetlands will respond. We integrate aspects of topography, land cover/land use and climate to model the permanence class of tens of thousands of wetlands at the western edge of the Prairie Pothole Region.
Ádám T. Kocsis, Qianshuo Zhao, Mark J. Costello, and Wolfgang Kiessling
Biogeosciences, 18, 6567–6578,Short summary
Biodiversity is under threat from the effects of global warming, and assessing the effects of climate change on areas of high species richness is of prime importance to conservation. Terrestrial and freshwater rich spots have been and will be less affected by climate change than other areas. However, marine rich spots of biodiversity are expected to experience more pronounced warming.
Rob Wilson, Kathy Allen, Patrick Baker, Gretel Boswijk, Brendan Buckley, Edward Cook, Rosanne D'Arrigo, Dan Druckenbrod, Anthony Fowler, Margaux Grandjean, Paul Krusic, and Jonathan Palmer
Biogeosciences, 18, 6393–6421,Short summary
We explore blue intensity (BI) – a low-cost method for measuring ring density – to enhance palaeoclimatology in Australasia. Calibration experiments, using several conifer species from Tasmania and New Zealand, model 50–80 % of the summer temperature variance. The implications of these results have profound consequences for high-resolution paleoclimatology in Australasia, as the speed and cheapness of BI generation could lead to a step change in our understanding of past climate in the region.
Alex R. Quijada-Rodriguez, Pou-Long Kuan, Po-Hsuan Sung, Mao-Ting Hsu, Garett J. P. Allen, Pung Pung Hwang, Yung-Che Tseng, and Dirk Weihrauch
Biogeosciences, 18, 6287–6300,Short summary
Anthropogenic CO2 is chronically acidifying aquatic ecosystems. We aimed to determine the impact of future freshwater acidification on the physiology and behaviour of an important aquaculture crustacean, Chinese mitten crabs. We report that elevated freshwater CO2 levels lead to impairment of calcification, locomotor behaviour, and survival and reduced metabolism in this species. Results suggest that present-day calcifying invertebrates could be heavily affected by freshwater acidification.
Junrong Zha and Qianlai Zhuang
Biogeosciences, 18, 6245–6269,Short summary
This study incorporated moss into an extant biogeochemistry model to simulate the role of moss in carbon dynamics in the Arctic. The interactions between higher plants and mosses and their competition for energy, water, and nutrients are considered in our study. We found that, compared with the previous model without moss, the new model estimated a much higher carbon accumulation in the region during the last century and this century.
Maria Belke-Brea, Florent Domine, Ghislain Picard, Mathieu Barrere, and Laurent Arnaud
Biogeosciences, 18, 5851–5869,Short summary
Expanding shrubs in the Arctic change snowpacks into a mix of snow, impurities and buried branches. Snow is a translucent medium into which light penetrates and gets partly absorbed by branches or impurities. Measurements of light attenuation in snow in Northern Quebec, Canada, showed (1) black-carbon-dominated light attenuation in snowpacks without shrubs and (2) buried branches influence radiation attenuation in snow locally, leading to melting and pockets of large crystals close to branches.
Sazlina Salleh and Andrew McMinn
Biogeosciences, 18, 5313–5326,Short summary
The benthic diatom communities in Tanjung Rhu, Malaysia, were regularly exposed to high light and temperature variability during the tidal cycle, resulting in low photosynthetic efficiency. We examined the impact of high temperatures on diatoms' photosynthetic capacities, and temperatures beyond 50 °C caused severe photoinhibition. At the same time, those diatoms exposed to temperatures of 40 °C did not show any sign of photoinhibition.
Cornelius Senf and Rupert Seidl
Biogeosciences, 18, 5223–5230,Short summary
Europe was affected by an extreme drought in 2018. We show that this drought has increased forest disturbances across Europe, especially central and eastern Europe. Disturbance levels observed 2018–2020 were the highest on record for 30 years. Increased forest disturbances were correlated with low moisture and high atmospheric water demand. The unprecedented impacts of the 2018 drought on forest disturbances demonstrate an urgent need to adapt Europe’s forests to a hotter and drier future.
Jessica L. McCarty, Juha Aalto, Ville-Veikko Paunu, Steve R. Arnold, Sabine Eckhardt, Zbigniew Klimont, Justin J. Fain, Nikolaos Evangeliou, Ari Venäläinen, Nadezhda M. Tchebakova, Elena I. Parfenova, Kaarle Kupiainen, Amber J. Soja, Lin Huang, and Simon Wilson
Biogeosciences, 18, 5053–5083,Short summary
Fires, including extreme fire seasons, and fire emissions are more common in the Arctic. A review and synthesis of current scientific literature find climate change and human activity in the north are fuelling an emerging Arctic fire regime, causing more black carbon and methane emissions within the Arctic. Uncertainties persist in characterizing future fire landscapes, and thus emissions, as well as policy-relevant challenges in understanding, monitoring, and managing Arctic fire regimes.
Alexander J. Winkler, Ranga B. Myneni, Alexis Hannart, Stephen Sitch, Vanessa Haverd, Danica Lombardozzi, Vivek K. Arora, Julia Pongratz, Julia E. M. S. Nabel, Daniel S. Goll, Etsushi Kato, Hanqin Tian, Almut Arneth, Pierre Friedlingstein, Atul K. Jain, Sönke Zaehle, and Victor Brovkin
Biogeosciences, 18, 4985–5010,Short summary
Satellite observations since the early 1980s show that Earth's greening trend is slowing down and that browning clusters have been emerging, especially in the last 2 decades. A collection of model simulations in conjunction with causal theory points at climatic changes as a key driver of vegetation changes in natural ecosystems. Most models underestimate the observed vegetation browning, especially in tropical rainforests, which could be due to an excessive CO2 fertilization effect in models.
Vincent Niderkorn, Annette Morvan-Bertrand, Aline Le Morvan, Angela Augusti, Marie-Laure Decau, and Catherine Picon-Cochard
Biogeosciences, 18, 4841–4853,Short summary
Climate change can change vegetation characteristics in grasslands with a potential impact on forage chemical composition and quality, as well as its use by ruminants. Using controlled conditions mimicking a future climatic scenario, we show that forage quality and ruminant digestion are affected in opposite ways by elevated atmospheric CO2 and an extreme event (heat wave, severe drought), indicating that different factors of climate change have to be considered together.
Melissa A. Ward, Tessa M. Hill, Chelsey Souza, Tessa Filipczyk, Aurora M. Ricart, Sarah Merolla, Lena R. Capece, Brady C O'Donnell, Kristen Elsmore, Walter C. Oechel, and Kathryn M. Beheshti
Biogeosciences, 18, 4717–4732,Short summary
Salt marshes and seagrass meadows ("blue carbon" habitats) can sequester and store high levels of organic carbon (OC), helping to mitigate climate change. In California blue carbon sediments, we quantified OC storage and exchange between these habitats. We find that (1) these salt marshes store about twice as much OC as seagrass meadows do and (2), while OC from seagrass meadows is deposited into neighboring salt marshes, little of this material is sequestered as "long-term" carbon.
Damien Couespel, Marina Lévy, and Laurent Bopp
Biogeosciences, 18, 4321–4349,Short summary
An alarming consequence of climate change is the oceanic primary production decline projected by Earth system models. These coarse-resolution models parameterize oceanic eddies. Here, idealized simulations of global warming with increasing resolution show that the decline in primary production in the eddy-resolved simulations is half as large as in the eddy-parameterized simulations. This stems from the high sensitivity of the subsurface nutrient transport to model resolution.
Wu Ma, Lu Zhai, Alexandria Pivovaroff, Jacquelyn Shuman, Polly Buotte, Junyan Ding, Bradley Christoffersen, Ryan Knox, Max Moritz, Rosie A. Fisher, Charles D. Koven, Lara Kueppers, and Chonggang Xu
Biogeosciences, 18, 4005–4020,Short summary
We use a hydrodynamic demographic vegetation model to estimate live fuel moisture dynamics of chaparral shrubs, a dominant vegetation type in fire-prone southern California. Our results suggest that multivariate climate change could cause a significant net reduction in live fuel moisture and thus exacerbate future wildfire danger in chaparral shrub systems.
Bertold Mariën, Inge Dox, Hans J. De Boeck, Patrick Willems, Sebastien Leys, Dimitri Papadimitriou, and Matteo Campioli
Biogeosciences, 18, 3309–3330,Short summary
The drivers of the onset of autumn leaf senescence for several deciduous tree species are still unclear. Therefore, we addressed (i) if drought impacts the timing of autumn leaf senescence and (ii) if the relationship between drought and autumn leaf senescence depends on the tree species. Our study suggests that the timing of autumn leaf senescence is conservative across years and species and even independent of drought stress.
Anna Katavouta and Richard G. Williams
Biogeosciences, 18, 3189–3218,Short summary
Diagnostics of the latest-generation Earth system models reveal the ocean will continue to absorb a large fraction of the anthropogenic carbon released to the atmosphere in the next century, with the Atlantic Ocean storing a large amount of this carbon relative to its size. The ability of the ocean to absorb carbon will reduce in the future as the ocean warms and acidifies. This reduction is larger in the Atlantic Ocean due to a weakening of the meridional overturning with changes in climate.
Genevieve Jay Brett, Daniel B. Whitt, Matthew C. Long, Frank Bryan, Kate Feloy, and Kelvin J. Richards
Biogeosciences, 18, 3123–3145,Short summary
We quantify one form of uncertainty in modeled 21st-century changes in phytoplankton growth. The supply of nutrients from deep to surface waters decreases in the warmer future ocean, but the effect on phytoplankton growth also depends on changes in available light, how much light and nutrient the plankton need, and how fast they can grow. These phytoplankton properties can be summarized as a biological timescale: when it is short, future growth decreases twice as much as when it is long.
Sean M. Ridge and Galen A. McKinley
Biogeosciences, 18, 2711–2725,Short summary
Approximately 40 % of the CO2 emissions from fossil fuel combustion and cement production have been absorbed by the ocean. The goal of the UNFCCC Paris Agreement is to reduce humanity's emissions so as to limit global warming to no more than 2 °C, and ideally less than 1.5 °C. If we achieve this level of mitigation, the ocean's uptake of carbon will be strongly reduced. Excess carbon trapped in the near-surface ocean will begin to mix back to the surface and will limit additional uptake.
Alexander Koch, Chris Brierley, and Simon L. Lewis
Biogeosciences, 18, 2627–2647,Short summary
Estimates of large-scale tree planting and forest restoration as a carbon sequestration tool typically miss a crucial aspect: the Earth system response to the increased land carbon sink from new vegetation. We assess the impact of tropical forest restoration using an Earth system model under a scenario that limits warming to 2 °C. Almost two-thirds of the carbon impact of forest restoration is offset by negative carbon cycle feedbacks, suggesting a more modest benefit than in previous studies.
Wei Min Hao, Matthew C. Reeves, L. Scott Baggett, Yves Balkanski, Philippe Ciais, Bryce L. Nordgren, Alexander Petkov, Rachel E. Corley, Florent Mouillot, Shawn P. Urbanski, and Chao Yue
Biogeosciences, 18, 2559–2572,Short summary
We examined the trends in the spatial and temporal distribution of the area burned in northern Eurasia from 2002 to 2016. The annual area burned in this region declined by 53 % during the 15-year period under analysis. Grassland fires in Kazakhstan dominated the fire activity, comprising 47 % of the area burned but accounting for 84 % of the decline. A wetter climate and the increase in grazing livestock in Kazakhstan are the major factors contributing to the decline in the area burned.
Hangxiao Li, Tianpeng Xu, Jing Ma, Futian Li, and Juntian Xu
Biogeosciences, 18, 1439–1449,Short summary
Few studies have investigated effects of ocean acidification and seasonal changes in temperature and day length on marine diatoms. We cultured a marine diatom under two CO2 levels and three combinations of temperature and day length, simulating different seasons, to investigate combined effects of these factors. Acidification had contrasting effects under different combinations, indicating that the future ocean may show different effects on diatoms in different clusters of factors.
Andrea J. Fassbender, James C. Orr, and Andrew G. Dickson
Biogeosciences, 18, 1407–1415,Short summary
A decline in upper-ocean pH with time is typically ascribed to ocean acidification. A more quantitative interpretation is often confused by failing to recognize the implications of pH being a logarithmic transform of hydrogen ion concentration rather than an absolute measure. This can lead to an unwitting misinterpretation of pH data. We provide three real-world examples illustrating this and recommend the reporting of both hydrogen ion concentration and pH in studies of ocean chemical change.
Claudia Hahn, Andreas Lüscher, Sara Ernst-Hasler, Matthias Suter, and Ansgar Kahmen
Biogeosciences, 18, 585–604,Short summary
While existing studies focus on the immediate effects of drought events on grassland productivity, long-term effects are mostly neglected. But, to conclude universal outcomes, studies must consider comprehensive ecosystem mechanisms. In our study, we found that the resistance of growth rates to drought in grasses varies across seasons, and positive legacy effects of drought indicate a high resilience. The high resilience compensates for immediate drought effects on grasses to a large extent.
Wim Verbruggen, Guy Schurgers, Stéphanie Horion, Jonas Ardö, Paulo N. Bernardino, Bernard Cappelaere, Jérôme Demarty, Rasmus Fensholt, Laurent Kergoat, Thomas Sibret, Torbern Tagesson, and Hans Verbeeck
Biogeosciences, 18, 77–93,Short summary
A large part of Earth's land surface is covered by dryland ecosystems, which are subject to climate extremes that are projected to increase under future climate scenarios. By using a mathematical vegetation model, we studied the impact of single years of extreme rainfall on the vegetation in the Sahel. We found a contrasting response of grasses and trees to these extremes, strongly dependent on the way precipitation is spread over the rainy season, as well as a long-term impact on CO2 uptake.
Yong Zhang, Sinéad Collins, and Kunshan Gao
Biogeosciences, 17, 6357–6375,Short summary
Our results show that ocean acidification, warming, increased light exposure and reduced nutrient availability significantly reduce the growth rate but increase particulate organic and inorganic carbon in cells in the coccolithophore Emiliania huxleyi, indicating biogeochemical consequences of future ocean changes on the calcifying microalga. Concurrent changes in nutrient concentrations and pCO2 levels predominantly affected E. huxleyi growth, photosynthetic carbon fixation and calcification.
Rong Bi, Stefanie M. H. Ismar-Rebitz, Ulrich Sommer, Hailong Zhang, and Meixun Zhao
Biogeosciences, 17, 6287–6307,Short summary
Lipids provide crucial insight into the trajectory of ecological functioning in changing environments. We experimentally explore responses of lipid biomarker production in phytoplankton to projected changes in temperature, nutrients and pCO2. Differential responses of lipid biomarkers indicate rearrangements of cellular carbon pools under future ocean scenarios. Such variations in lipid biomarker production would have important impacts on marine ecological functions and biogeochemical cycles.
George Roff, Jennifer Joseph, and Peter J. Mumby
Biogeosciences, 17, 5909–5918,Short summary
In recent decades, extensive mortality of reef-building corals throughout the Caribbean region has led to the erosion of reef frameworks and declines in biodiversity. Using field observations, models, and high-precision U–Th dating, we quantified changes in the structural complexity of coral reef frameworks over the past 2 decades. Structural complexity was stable at reef scales, yet bioerosion led to declines in small-scale microhabitat complexity with cascading effects on cryptic fauna.
Yota Harada, Rod M. Connolly, Brian Fry, Damien T. Maher, James Z. Sippo, Luke C. Jeffrey, Adam J. Bourke, and Shing Yip Lee
Biogeosciences, 17, 5599–5613,Short summary
In 2015–2016, an extensive area of mangroves along ~ 1000 km of coastline in the Gulf of Carpentaria, Australia, experienced dieback as a result of a climatic extreme event that included drought conditions and low sea levels. Multiannual field campaigns conducted from 2016 to 2018 show substantial recovery of the mangrove vegetation. However, stable isotopes suggest long-lasting changes in carbon, nitrogen and sulfur cycling following the dieback.
Lena R. Boysen, Victor Brovkin, Julia Pongratz, David M. Lawrence, Peter Lawrence, Nicolas Vuichard, Philippe Peylin, Spencer Liddicoat, Tomohiro Hajima, Yanwu Zhang, Matthias Rocher, Christine Delire, Roland Séférian, Vivek K. Arora, Lars Nieradzik, Peter Anthoni, Wim Thiery, Marysa M. Laguë, Deborah Lawrence, and Min-Hui Lo
Biogeosciences, 17, 5615–5638,Short summary
We find a biogeophysically induced global cooling with strong carbon losses in a 20 million square kilometre idealized deforestation experiment performed by nine CMIP6 Earth system models. It takes many decades for the temperature signal to emerge, with non-local effects playing an important role. Despite a consistent experimental setup, models diverge substantially in their climate responses. This study offers unprecedented insights for understanding land use change effects in CMIP6 models.
Vivek K. Arora, Anna Katavouta, Richard G. Williams, Chris D. Jones, Victor Brovkin, Pierre Friedlingstein, Jörg Schwinger, Laurent Bopp, Olivier Boucher, Patricia Cadule, Matthew A. Chamberlain, James R. Christian, Christine Delire, Rosie A. Fisher, Tomohiro Hajima, Tatiana Ilyina, Emilie Joetzjer, Michio Kawamiya, Charles D. Koven, John P. Krasting, Rachel M. Law, David M. Lawrence, Andrew Lenton, Keith Lindsay, Julia Pongratz, Thomas Raddatz, Roland Séférian, Kaoru Tachiiri, Jerry F. Tjiputra, Andy Wiltshire, Tongwen Wu, and Tilo Ziehn
Biogeosciences, 17, 4173–4222,Short summary
Since the preindustrial period, land and ocean have taken up about half of the carbon emitted into the atmosphere by humans. Comparison of different earth system models with the carbon cycle allows us to assess how carbon uptake by land and ocean differs among models. This yields an estimate of uncertainty in our understanding of how land and ocean respond to increasing atmospheric CO2. This paper summarizes results from two such model intercomparison projects that use an idealized scenario.
Barnes, J. D., Balaguer, L., Manrique, E., Elvira, S., and Davison, A. W.: A reappraisal of the use of DMSO for the extraction and determination of chlorophylls, Environ. Exp. Bot., 32, 85–100, 1992. a
Biasi, C., Meyer, H., Rusalimova, O., Hämmerle, R., Kaiser, C., Baranyi, C., Daims, H., Lashchinsky, N., Barsukov, P., and Richter, A.: Initial effects of experimental warming on carbon exchange rates, plant growth and microbial dynamics of a lichen-rich dwarf shrub tundra in Siberia, Plant Soil, 307, 191–205, https://doi.org/10.1007/s11104-008-9596-2, 2008. a
Bokhorst, S., Bjerke, J. W., Davey, M. P., Taulavuori, K., Taulavuori, E., Laine, K., Callaghan, T. V., and Phoenix, G. K.: Impacts of extreme winter warming events on plant physiology in a sub-Arctic heath community, Physiol. Plantarum, 140, 128–140, https://doi.org/10.1111/j.1399-3054.2010.01386.x, 2010. a, b
Broder, T., Blodau, C., Biester, H., and Knorr, K. H.: Sea spray, trace elements, and decomposition patterns as possible constraints on the evolution of CH4 and CO2 concentrations and isotopic signatures in oceanic ombrotrophic bogs, Biogeochemistry, 122, 327–342, https://doi.org/10.1007/s10533-014-0044-5, 2015. a
Brooks, A. and Farquhar, G. D.: Effect of temperature on the CO2/O2 specificity of ribulose-1,5-bisphosphate carboxylase/oxygenase and the rate of respiration in the light, Planta, 165, 397–406, 1985. a
Edgington, E. and Onghena, P.: Randomization Tests, Fourth Edition, Statistics: A Series of Textbooks and Monographs, Taylor & Francis, New York, 2007. a
Fritz, C., Pancotto, V. A., Elzenga, J. T., Visser, E. J., Grootjans, A. P., Pol, A., Iturraspe, R., Roelofs, J. G., and Smolders, A. J.: Zero methane emission bogs: Extreme rhizosphere oxygenation by cushion plants in Patagonia, New Phytol., 190, 398–408, https://doi.org/10.1111/j.1469-8137.2010.03604.x, 2011. a, b, c
Gallego-Sala, A. V., Charman, D. J., Brewer, S., Page, S. E., Prentice, I. C., Friedlingstein, P., Moreton, S., Amesbury, M. J., Beilman, D. W., Björck, S., Blyakharchuk, T., Bochicchio, C., Booth, R. K., Bunbury, J., Camill, P., Carless, D., Chimner, R. A., Clifford, M., Cressey, E., Courtney-Mustaphi, C., De Vleeschouwer, F., de Jong, R., Fialkiewicz-Koziel, B., Finkelstein, S. A., Garneau, M., Githumbi, E., Hribjlan, J., Holmquist, J., Hughes, P. D., Jones, C., Jones, M. C., Karofeld, E., Klein, E. S., Kokfelt, U., Korhola, A., Lacourse, T., Le Roux, G., Lamentowicz, M., Large, D., Lavoie, M., Loisel, J., Mackay, H., MacDonald, G. M., Makila, M., Magnan, G., Marchant, R., Marcisz, K., Martínez Cortizas, A., Massa, C., Mathijssen, P., Mauquoy, D., Mighall, T., Mitchell, F. J., Moss, P., Nichols, J., Oksanen, P. O., Orme, L., Packalen, M. S., Robinson, S., Roland, T. P., Sanderson, N. K., Sannel, A. B. K., Silva-Sánchez, N., Steinberg, N., Swindles, G. T., Turner, T. E., Uglow, J., Väliranta, M., van Bellen, S., van der Linden, M., van Geel, B., Wang, G., Yu, Z., Zaragoza-Castells, J., and Zhao, Y.: Latitudinal limits to the predicted increase of the peatland carbon sink with warming, Nat. Clim. Change, 8, 907–913, https://doi.org/10.1038/s41558-018-0271-1, 2018. a
Grootjans, A., Iturraspe, R., Lanting, A., Fritz, C., and Joosten, H.: Ecohydrological features of some contrasting mires in Tierra del Fuego, Mires and Peat, Argentina, 6, 1–15, 2010. a
Holl, D., Pancotto, V., Heger, A., Camargo, S. J., and Kutzbach, L.: Cushion bogs are stronger carbon dioxide net sinks than moss-dominated bogs as revealed by eddy covariance measurements on Tierra del Fuego, Argentina, Biogeosciences, 16, 3397–3423, https://doi.org/10.5194/bg-16-3397-2019, 2019. a, b, c, d, e
Kleinebecker, T., Hölzel, N., and Vogel, A.: Gradients of continentality and moisture in South Patagonian ombrotrophic peatland vegetation, Folia Geobot., 42, 363–382, 2007. a
Kleinebecker, T., Hölzel, N., and Vogel, A.: South Patagonian ombrotrophic bog vegetation reflects biogeochemical gradients at the landscape level, Journal of Vegetation Science, 19, 151–160, 2008. a
Liancourt, P., Sharkhuu, A., Ariuntsetseg, L., Boldgiv, B., Helliker, B. R., Plante, A. F., Petraitis, P. S., and Casper, B. B.: Temporal and spatial variation in how vegetation alters the soil moisture response to climate manipulation, Plant Soil, 351, 249–261, https://doi.org/10.1007/s11104-011-0956-y, 2012. a
Livingston, G. and Hutchinson, G.: Enclosure-based measurement of trace gas exchange: applications and sources of error, in: Biogenic trace gases: measuring emissions from soil and water, 51, 14–51, Blackwell Science, Cambridge, 1995. a
Mahecha, M. D., Reichstein, M., Carvalhais, N., Lasslop, G., Lange, H., Seneviratne, S. I., Vargas, R., Ammann, C., Arain, M. A., Cescatti, A., Janssens, I. A., Migliavacca, M., Montagnani, L., and Richardson, A. D.: Global Convergence in the Temperature Sensitivity of Respiration at Ecosystem Level, Science, 329, 838–840, 2010. a
Mäkiranta, P., Laiho, R., Mehtätalo, L., Straková, P., Sormunen, J., Minkkinen, K., Penttilä, T., Fritze, H., and Tuittila, E.-S.: Responses of phenology and biomass production of boreal fens to climate warming under different water-table level regimes, Glob. Change Biol., 24, 944–956, https://doi.org/10.1111/gcb.13934, 2017. a
Marion, G. M., Henry, G. H., Freckman, D. W., Johnstone, J., Jones, G., Jones, M. H., Lévesque, E., Molau, U., Mølgaard, P., Parsons, A. N., Svoboda, J., and Virginia, R. A.: Open-top designs for manipulating field temperature in high-latitude ecosystems, Glob. Change Biol., 3, 20–32, https://doi.org/10.1111/j.1365-2486.1997.gcb136.x, 1997. a, b, c, d, e
Münchberger, W., Knorr, K.-H., Blodau, C., Pancotto, V. A., and Kleinebecker, T.: Zero to moderate methane emissions in a densely rooted, pristine Patagonian bog – biogeochemical controls as revealed from isotopic evidence, Biogeosciences, 16, 541–559, https://doi.org/10.5194/bg-16-541-2019, 2019. a, b, c
Parish, F., Sirin, A., Charman, D., Joosten, H., Minaeva, T., and Silvius, M.: Assessment on peatlands, biodiversity and climate change, Global Environment Centre, Kuala Lumpur, 2008. a
Peñuelas, J., Gordon, C., Llorens, L., Nielsen, T., Tietema, A., Beier, C., Bruna, P., Emmett, B., Estiarte, M., and Gorissen, A.: Nonintrusive field experiments show different plant responses to warming and drought among sites, seasons, and species in a north-south European gradient, Ecosystems, 7, 598–612, https://doi.org/10.1007/s10021-004-0179-7, 2004. a
Pérez-Harguindeguy, N., Díaz, S., Garnier, E., Lavorel, S., Poorter, H., Jaureguiberry, P., Cornwell, W. K., Craine, J. M., Gurvich, D. E., Urcelay, C., Veneklaas, E. J., Reich, P. B., Poorter, L., Wright, I. J., Ray, P., Enrico, L., Pausas, J. G., Vos, A. C. D., Buchmann, N., Funes, G., Quétier, F., Hodgson, J. G., Thompson, K., Morgan, H. D., Steege, H., Heijden, M. G. A. V. D., Sack, L., Blonder, B., Poschlod, P., Vaieretti, M. V., Conti, G., Staver, A. C., Aquino, S., and Cornelissen, J. H. C.: New handbook for standardised measurement of plant functional traits worldwide, Aust. J. Bot., 64, 715–716, https://doi.org/10.1071/BT12225, 2016. a
Ponce, J. F. and Fernández, M.: Climatic and environmental history of Isla de los Estados, Argentina, Springer, New York, 2014. a
Robson, T. M., Pancotto, V. A., Flint, S. D., Ballaré, C. L., Sala, O. E., Scopel, A. L., and Caldwell, M. M.: Six years of solar UV-B manipulations affect growth of Sphagnum and vascular plants in a Tierra del Fuego peatland, New Phytol., 160, 379–389, https://doi.org/10.1046/j.1469-8137.2003.00898.x, 2003. a
Rousseaux, M. C., Scopel, A. L., Searles, P. S., Caldwell, M. M., Sala, O. E., and Ballaré, C. L.: Responses to solar ultraviolet-B radiation in a shrub-dominated natural ecosystem of Tierra del Fuego (southern Argentina), Glob. Change Biol., 7, 467–478, https://doi.org/10.1046/j.1365-2486.2001.00413.x, 2001. a
Runkle, B. R. K., Sachs, T., Wille, C., Pfeiffer, E.-M., and Kutzbach, L.: Bulk partitioning the growing season net ecosystem exchange of CO2 in Siberian tundra reveals the seasonality of its carbon sequestration strength, Biogeosciences, 10, 1337–1349, https://doi.org/10.5194/bg-10-1337-2013, 2013. a
Rustad, L. E., Campbell, J. L., Marion, G. M., Norby, R. J., Mitchell, M. J., Hartley, A. E., Cornelissen, J. H., Gurevitch, J., Alward, R., Beier, C., Burke, I., Canadell, J., Callaghan, T., Christensen, T. R., Fahnestock, J., Fernandez, I., Harte, J., Hollister, R., John, H., Ineson, P., Johnson, M. G., Jonasson, S., John, L., Linder, S., Lukewille, A., Masters, G., Melillo, J., Mickelsen, A., Neill, C., Olszyk, D. M., Press, M., Pregitzer, K., Robinson, C., Rygiewiez, P. T., Sala, O., Schmidt, I. K., Shaver, G., Thompson, K., Tingey, D. T., Verburg, P., Wall, D., Welker, J., and Wright, R.: A meta-analysis of the response of soil respiration, net nitrogen mineralization, and aboveground plant growth to experimental ecosystem warming, Oecologia, 126, 543–562, https://doi.org/10.1007/s004420000544, 2001. a
Santana, A., Porter, C., Butorovic, N., and Olave, C.: Primeros Antecedentes Climatológicos De Estaciones (Aws) En El Canal Beagle, Anales Instituto Patagonia (Chile), 34, 5–20, 2006. a
Sharkhuu, A., Plante, A. F., Enkhmandal, O., Casper, B. B., Helliker, B. R., Boldgiv, B., and Petraitis, P. S.: Effects of open-top passive warming chambers on soil respiration in the semi-arid steppe to taiga forest transition zone in Northern Mongolia, Biogeochemistry, 115, 333–348, https://doi.org/10.1007/s10533-013-9839-z, 2013. a
Tuhkanen, S.: The climate of Tierra del Fuego from a vegetation geographical point of view and its ecoclimatic counterparts elsewhere, Finnish Botanical Publishing Board, Helsinki, 1992. a
van Bellen, S., Mauquoy, D., Hughes, P. D., Roland, T. P., Daley, T. J., Loader, N. J., Street-Perrott, F. A., Rice, E. M., Pancotto, V. A., and Payne, R. J.: Late-Holocene climate dynamics recorded in the peat bogs of Tierra del Fuego, South America, Holocene, 26, 489–501, https://doi.org/10.1177/0959683615609756, 2016. a
Virtanen, P., Gommers, R., Oliphant, T. E., Haberland, M., Reddy, T., Cournapeau, D., Burovski, E., Peterson, P., Weckesser, W., Bright, J., van der Walt, S. J., Brett, M., Wilson, J., Millman, K. J., Mayorov, N., Nelson, A. R., Jones, E., Kern, R., Larson, E., Carey, C. J., Polat, I., Feng, Y., Moore, E. W., VanderPlas, J., Laxalde, D., Perktold, J., Cimrman, R., Henriksen, I., Quintero, E. A., Harris, C. R., Archibald, A. M., Ribeiro, A. H., Pedregosa, F., van Mulbregt, P., Vijaykumar, A., Bardelli, A. P., Rothberg, A., Hilboll, A., Kloeckner, A., Scopatz, A., Lee, A., Rokem, A., Woods, C. N., Fulton, C., Masson, C., Häggström, C., Fitzgerald, C., Nicholson, D. A., Hagen, D. R., Pasechnik, D. V., Olivetti, E., Martin, E., Wieser, E., Silva, F., Lenders, F., Wilhelm, F., Young, G., Price, G. A., Ingold, G. L., Allen, G. E., Lee, G. R., Audren, H., Probst, I., Dietrich, J. P., Silterra, J., Webber, J. T., Slavič, J., Nothman, J., Buchner, J., Kulick, J., Schönberger, J. L., de Miranda Cardoso, J. V., Reimer, J., Harrington, J., Rodríguez, J. L. C., Nunez-Iglesias, J., Kuczynski, J., Tritz, K., Thoma, M., Newville, M., Kümmerer, M., Bolingbroke, M., Tartre, M., Pak, M., Smith, N. J., Nowaczyk, N., Shebanov, N., Pavlyk, O., Brodtkorb, P. A., Lee, P., McGibbon, R. T., Feldbauer, R., Lewis, S., Tygier, S., Sievert, S., Vigna, S., Peterson, S., More, S., Pudlik, T., Oshima, T., Pingel, T. J., Robitaille, T. P., Spura, T., Jones, T. R., Cera, T., Leslie, T., Zito, T., Krauss, T., Upadhyay, U., Halchenko, Y. O., and Vázquez-Baeza, Y.: SciPy 1.0: fundamental algorithms for scientific computing in Python, Nat. Methods, 17, 261–272, https://doi.org/10.1038/s41592-019-0686-2, 2020. a, b
Walker, M. D., Wahren, C. H., Hollister, R. D., Henry, G. H., Ahlquist, L. E., Alatalo, J. M., Bret-Harte, M. S., Calef, M. P., Callaghan, T. V., Carroll, A. B., Epstein, H. E., Jónsdóttir, I. S., Klein, J. A., Magnússon, B., Molau, U., Oberbauer, S. F., Rewa, S. P., Robinson, C. H., Shaver, G. R., Suding, K. N., Thompson, C. C., Tolvanen, A., Totland, Ø., Turner, P. L., Tweedie, C. E., Webber, P. J., and Wookey, P. A.: Plant community responses to experimental warming across the tundra biome, Proc. Natl. Acad. Sci. USA, 103, 1342–1346, https://doi.org/10.1073/pnas.0503198103, 2006. a, b, c
Wieners, K.-H., Giorgetta, M., Jungclaus, J., Reick, C., Esch, M., Bittner, M., Gayler, V., Haak, H., de Vrese, P., Raddatz, T., Mauritsen, T., von Storch, J.-S., Behrens, J., Brovkin, V., Claussen, M., Crueger, T., Fast, I., Fiedler, S., Hagemann, S., Hohenegger, C., Jahns, T., Kloster, S., Kinne, S., Lasslop, G., Kornblueh, L., Marotzke, J., Matei, D., Meraner, K., Mikolajewicz, U., Modali, K., Müller, W., Nabel, J., Notz, D., Peters, K., Pincus, R., Pohlmann, H., Pongratz, J., Rast, S., Schmidt, H., Schnur, R., Schulzweida, U., Six, K., Stevens, B., Voigt, A., and Roeckner, E.: MPI-M MPI-ESM1.2-LR model output prepared for CMIP6 ScenarioMIP ssp126. Version 20210323, https://doi.org/10.22033/ESGF/CMIP6.6690, 2019a. a
Wieners, K.-H., Giorgetta, M., Jungclaus, J., Reick, C., Esch, M., Bittner, M., Gayler, V., Haak, H., de Vrese, P., Raddatz, T., Mauritsen, T., von Storch, J.-S., Behrens, J., Brovkin, V., Claussen, M., Crueger, T., Fast, I., Fiedler, S., Hagemann, S., Hohenegger, C., Jahns, T., Kloster, S., Kinne, S., Lasslop, G., Kornblueh, L., Marotzke, J., Matei, D., Meraner, K., Mikolajewicz, U., Modali, K., Müller, W., Nabel, J., Notz, D., Peters, K., Pincus, R., Pohlmann, H., Pongratz, J., Rast, S., Schmidt, H., Schnur, R., Schulzweida, U., Six, K., Stevens, B., Voigt, A., and Roeckner, E.: MPI-M MPI-ESM1.2-LR model output prepared for CMIP6 ScenarioMIP ssp585. Version 20210323, https://doi.org/10.22033/ESGF/CMIP6.6705, 2019b. a
Wilson, R. M., Hopple, A. M., Tfaily, M. M., Sebestyen, S. D., Schadt, C. W., Pfeifer-Meister, L., Medvedeff, C., Mcfarlane, K. J., Kostka, J. E., Kolton, M., Kolka, R. K., Kluber, L. A., Keller, J. K., Guilderson, T. P., Griffiths, N. A., Chanton, J. P., Bridgham, S. D., and Hanson, P. J.: Stability of peatland carbon to rising temperatures, Nat. Commun., 7, 1–10, https://doi.org/10.1038/ncomms13723, 2016. a
Zhang, Z., Zhang, R., Cescatti, A., Wohlfahrt, G., Buchmann, N., Zhu, J., Chen, G., Moyano, F., Pumpanen, J., Hirano, T., Takagi, K., and Merbold, L.: Effect of climate warming on the annual terrestrial net ecosystem CO2 exchange globally in the boreal and temperate regions, Sci. Rep., 7, 1–11, https://doi.org/10.1038/s41598-017-03386-5, 2017. a
We investigated the response of a wetland plant community to elevated temperature conditions in a cushion bog on Tierra del Fuego, Argentina. We measured carbon dioxide fluxes at experimentally warmed plots and at control plots. Warmed plant communities sequestered between 55 % and 85 % less carbon dioxide than untreated control cushions over the main growing season. Our results suggest that even moderate future warming could decrease the carbon sink function of austral cushion bogs.
We investigated the response of a wetland plant community to elevated temperature conditions in...