Articles | Volume 11, issue 22
Biogeosciences, 11, 6307–6322, 2014
https://doi.org/10.5194/bg-11-6307-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Biogeosciences, 11, 6307–6322, 2014
https://doi.org/10.5194/bg-11-6307-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article 24 Nov 2014
Research article | 24 Nov 2014
Annual CO2 budget and seasonal CO2 exchange signals at a high Arctic permafrost site on Spitsbergen, Svalbard archipelago
J. Lüers et al.
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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, https://doi.org/10.5194/essd-14-179-2022, https://doi.org/10.5194/essd-14-179-2022, 2022
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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.
Katharina Jentzsch, Julia Boike, and Thomas Foken
Atmos. Meas. Tech., 14, 7291–7296, https://doi.org/10.5194/amt-14-7291-2021, https://doi.org/10.5194/amt-14-7291-2021, 2021
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Very small CO2 fluxes are measured at night in Arctic regions. If the sensible heat flux is not close to zero under these conditions, the WPL correction will take values on the order of the flux. A special quality control is proposed for these cases.
Noah D. Smith, Sarah E. Chadburn, Eleanor J. Burke, Kjetil Schanke Aas, Inge H. J. Althuizen, Julia Boike, Casper Tai Christiansen, Bernd Etzelmüller, Thomas Friborg, Hanna Lee, Heather Rumbold, Rachael Turton, and Sebastian Westermann
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-285, https://doi.org/10.5194/gmd-2021-285, 2021
Preprint under review for GMD
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The arctic has large areas of small mounds, caused by ice lifting up the soil. Snow blown by wind gathers in hollows next to these mounds, insulating them in winter. The hollows tend to be wetter, so the soil absorbs more heat in summer. The warm wet soil in the hollows decomposes, releasing methane: a powerful greenhouse gas. We’ve made a model of this, tested how it behaves and whether it looks like sites in Scandinavia and Siberia. Sometimes, we get more methane than a model without mounds.
Sarah E. Chadburn, Eleanor J. Burke, Angela V. Gallego-Sala, Noah D. Smith, M. Syndonia Bret-Harte, Dan J. Charman, Julia Drewer, Colin W. Edgar, Eugenie S. Euskirchen, Krzysztof Fortuniak, Yao Gao, Mahdi Nakhavali, Włodzimierz Pawlak, Edward A. G. Schuur, and Sebastian Westermann
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-263, https://doi.org/10.5194/gmd-2021-263, 2021
Revised manuscript accepted for GMD
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We present a new method to include peatlands in an Earth System Model (ESM). Peatlands store huge amounts of carbon that accumulates very slowly, yet can be rapidly destabilised, emitting greenhouse gases. Our model captures the dynamic nature of peat by simulating the change of surface height and physical properties of the soil as carbon is added (from plants) or decomposed. Thus we model peat dynamics and its threshold behaviours that can lead to destabilisation for the first time in an ESM.
Stefan Kruse, Simone M. Stuenzi, Julia Boike, Moritz Langer, Josias Gloy, and Ulrike Herzschuh
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2021-304, https://doi.org/10.5194/gmd-2021-304, 2021
Preprint under review for GMD
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We coupled established models for boreal forest (LAVESI) and permafrost dynamics (CryoGrid) in Siberia for investigating interactions of the diverse vegetation layer with permafrost soils. Our tests showed improved active layer depth estimations and newly included species grow according to their species-specific limits. We conclude that the new model system can be applied to simulate boreal forest dynamics and transitions under global warming and disturbances expanding our knowledge.
Léo C. P. Martin, Jan Nitzbon, Johanna Scheer, Kjetil S. Aas, Trond Eiken, Moritz Langer, Simon Filhol, Bernd Etzelmüller, and Sebastian Westermann
The Cryosphere, 15, 3423–3442, https://doi.org/10.5194/tc-15-3423-2021, https://doi.org/10.5194/tc-15-3423-2021, 2021
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It is important to understand how permafrost landscapes respond to climate changes because their thaw can contribute to global warming. We investigate how a common permafrost morphology degrades using both field observations of the surface elevation and numerical modeling. We show that numerical models accounting for topographic changes related to permafrost degradation can reproduce the observed changes in nature and help us understand how parameters such as snow influence this phenomenon.
Lydia Stolpmann, Caroline Coch, Anne Morgenstern, Julia Boike, Michael Fritz, Ulrike Herzschuh, Kathleen Stoof-Leichsenring, Yury Dvornikov, Birgit Heim, Josefine Lenz, Amy Larsen, Katey Walter Anthony, Benjamin Jones, Karen Frey, and Guido Grosse
Biogeosciences, 18, 3917–3936, https://doi.org/10.5194/bg-18-3917-2021, https://doi.org/10.5194/bg-18-3917-2021, 2021
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Our new database summarizes DOC concentrations of 2167 water samples from 1833 lakes in permafrost regions across the Arctic to provide insights into linkages between DOC and environment. We found increasing lake DOC concentration with decreasing permafrost extent and higher DOC concentrations in boreal permafrost sites compared to tundra sites. Our study shows that DOC concentration depends on the environmental properties of a lake, especially permafrost extent, ecoregion, and vegetation.
Juditha Undine Schmidt, Bernd Etzelmüller, Thomas Vikhamar Schuler, Florence Magnin, Julia Boike, Moritz Langer, and Sebastian Westermann
The Cryosphere, 15, 2491–2509, https://doi.org/10.5194/tc-15-2491-2021, https://doi.org/10.5194/tc-15-2491-2021, 2021
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This study presents rock surface temperatures (RSTs) of steep high-Arctic rock walls on Svalbard from 2016 to 2020. The field data show that coastal cliffs are characterized by warmer RSTs than inland locations during winter seasons. By running model simulations, we analyze factors leading to that effect, calculate the surface energy balance and simulate different future scenarios. Both field data and model results can contribute to a further understanding of RST in high-Arctic rock walls.
Thomas Schneider von Deimling, Hanna Lee, Thomas Ingeman-Nielsen, Sebastian Westermann, Vladimir Romanovsky, Scott Lamoureux, Donald A. Walker, Sarah Chadburn, Erin Trochim, Lei Cai, Jan Nitzbon, Stephan Jacobi, and Moritz Langer
The Cryosphere, 15, 2451–2471, https://doi.org/10.5194/tc-15-2451-2021, https://doi.org/10.5194/tc-15-2451-2021, 2021
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Climate warming puts infrastructure built on permafrost at risk of failure. There is a growing need for appropriate model-based risk assessments. Here we present a modelling study and show an exemplary case of how a gravel road in a cold permafrost environment in Alaska might suffer from degrading permafrost under a scenario of intense climate warming. We use this case study to discuss the broader-scale applicability of our model for simulating future Arctic infrastructure failure.
Jan Nitzbon, Moritz Langer, Léo C. P. Martin, Sebastian Westermann, Thomas Schneider von Deimling, and Julia Boike
The Cryosphere, 15, 1399–1422, https://doi.org/10.5194/tc-15-1399-2021, https://doi.org/10.5194/tc-15-1399-2021, 2021
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We used a numerical model to investigate how small-scale landscape heterogeneities affect permafrost thaw under climate-warming scenarios. Our results show that representing small-scale heterogeneities in the model can decide whether a landscape is water-logged or well-drained in the future. This in turn affects how fast permafrost thaws under warming. Our research emphasizes the importance of considering small-scale processes in model assessments of permafrost thaw under climate change.
Bernd Etzelmüller, Justyna Czekirda, Florence Magnin, Pierre-Allain Duvillard, Emmanuel Malet, Ludo Ravanel, Andreas Aspaas, Lene Kristensen, Ingrid Skrede, Gudrun D. Majala, Benjamin Jacobs, Johannes Leinauer, Christian Hauck, Christin Hilbich, Martina Böhme, Reginald Hermanns, Harald Ø. Eriksen, Michael Krautblatter, and Sebastian Westermann
Earth Surf. Dynam. Discuss., https://doi.org/10.5194/esurf-2021-10, https://doi.org/10.5194/esurf-2021-10, 2021
Revised manuscript accepted for ESurf
Simone Maria Stuenzi, Julia Boike, William Cable, Ulrike Herzschuh, Stefan Kruse, Luidmila A. Pestryakova, Thomas Schneider von Deimling, Sebastian Westermann, Evgenii S. Zakharov, and Moritz Langer
Biogeosciences, 18, 343–365, https://doi.org/10.5194/bg-18-343-2021, https://doi.org/10.5194/bg-18-343-2021, 2021
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Boreal forests in eastern Siberia are an essential component of global climate patterns. We use a physically based model and field measurements to study the interactions between forests, permanently frozen ground and the atmosphere. We find that forests exert a strong control on the thermal state of permafrost through changing snow cover dynamics and altering the surface energy balance, through absorbing most of the incoming solar radiation and suppressing below-canopy turbulent fluxes.
Lei Cai, Hanna Lee, Kjetil Schanke Aas, and Sebastian Westermann
The Cryosphere, 14, 4611–4626, https://doi.org/10.5194/tc-14-4611-2020, https://doi.org/10.5194/tc-14-4611-2020, 2020
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A sub-grid representation of excess ground ice in the Community Land Model (CLM) is developed as novel progress in modeling permafrost thaw and its impacts under the warming climate. The modeled permafrost degradation with sub-grid excess ice follows the pathway that continuous permafrost transforms into discontinuous permafrost before it disappears, including surface subsidence and talik formation, which are highly permafrost-relevant landscape changes excluded from most land models.
Jean-Louis Bonne, Hanno Meyer, Melanie Behrens, Julia Boike, Sepp Kipfstuhl, Benjamin Rabe, Toni Schmidt, Lutz Schönicke, Hans Christian Steen-Larsen, and Martin Werner
Atmos. Chem. Phys., 20, 10493–10511, https://doi.org/10.5194/acp-20-10493-2020, https://doi.org/10.5194/acp-20-10493-2020, 2020
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This study introduces 2 years of continuous near-surface in situ observations of the stable isotopic composition of water vapour in parallel with precipitation in north-eastern Siberia. We evaluate the atmospheric transport of moisture towards the region of our observations with simulations constrained by meteorological reanalyses and use this information to interpret the temporal variations of the vapour isotopic composition from seasonal to synoptic timescales.
Inge Grünberg, Evan J. Wilcox, Simon Zwieback, Philip Marsh, and Julia Boike
Biogeosciences, 17, 4261–4279, https://doi.org/10.5194/bg-17-4261-2020, https://doi.org/10.5194/bg-17-4261-2020, 2020
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Based on topsoil temperature data for different vegetation types at a low Arctic tundra site, we found large small-scale variability. Winter temperatures were strongly influenced by vegetation through its effects on snow. Summer temperatures were similar below most vegetation types and not consistently related to late summer permafrost thaw depth. Given that vegetation type defines the relationship between winter and summer soil temperature and thaw depth, it controls permafrost vulnerability.
Jaroslav Obu, Sebastian Westermann, Gonçalo Vieira, Andrey Abramov, Megan Ruby Balks, Annett Bartsch, Filip Hrbáček, Andreas Kääb, and Miguel Ramos
The Cryosphere, 14, 497–519, https://doi.org/10.5194/tc-14-497-2020, https://doi.org/10.5194/tc-14-497-2020, 2020
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Little is known about permafrost in the Antarctic outside of the few research stations. We used a simple equilibrium permafrost model to estimate permafrost temperatures in the whole Antarctic. The lowest permafrost temperature on Earth is −36 °C in the Queen Elizabeth Range in the Transantarctic Mountains. Temperatures are commonly between −23 and −18 °C in mountainous areas rising above the Antarctic Ice Sheet, between −14 and −8 °C in coastal areas, and up to 0 °C on the Antarctic Peninsula.
Joel Fiddes, Kristoffer Aalstad, and Sebastian Westermann
Hydrol. Earth Syst. Sci., 23, 4717–4736, https://doi.org/10.5194/hess-23-4717-2019, https://doi.org/10.5194/hess-23-4717-2019, 2019
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In this paper we address one of the big challenges in snow hydrology, namely the accurate simulation of the seasonal snowpack in ungauged regions. We do this by assimilating satellite observations of snow cover into a modelling framework. Importantly (and a novelty of the paper), we include a clustering approach that permits highly efficient ensemble simulations. Efficiency gains and dependency on purely global datasets, means that this method can be applied over large areas anywhere on Earth.
Florence Magnin, Bernd Etzelmüller, Sebastian Westermann, Ketil Isaksen, Paula Hilger, and Reginald L. Hermanns
Earth Surf. Dynam., 7, 1019–1040, https://doi.org/10.5194/esurf-7-1019-2019, https://doi.org/10.5194/esurf-7-1019-2019, 2019
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This study proposes the first permafrost (i.e. ground with temperature permanently < 0 °C) map covering the steep rock slopes of Norway. It was created by using rock temperature data collected at the near surface of 25 rock walls spread across the country between 2010 and 2018. The map shows that permafrost mostly exists above 1300–1400 m a.s.l. in southern Norway and close to sea level in northern Norway. The results have strong potential for the study of rock wall sliding and failure.
Lei Cai, Hanna Lee, Sebastian Westermann, and Kjetil Schanke Aas
The Cryosphere Discuss., https://doi.org/10.5194/tc-2019-230, https://doi.org/10.5194/tc-2019-230, 2019
Preprint withdrawn
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We develop a sub-grid representation of excess ground ice in the Community Land Model (CLM) by adding three landunits to the original CLM sub-grid hierarchy, in order to prescribe three different excess ice conditions in one grid cell. Single-grid simulations verify the potential of the model development on better projecting excess ice melt in a warming climate. Global simulations recommend the proper way of applying the model development with the existing excess ice dataset.
Jan Nitzbon, Moritz Langer, Sebastian Westermann, Léo Martin, Kjetil Schanke Aas, and Julia Boike
The Cryosphere, 13, 1089–1123, https://doi.org/10.5194/tc-13-1089-2019, https://doi.org/10.5194/tc-13-1089-2019, 2019
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We studied the stability of ice wedges (massive bodies of ground ice in permafrost) under recent climatic conditions in the Lena River delta of northern Siberia. For this we used a novel modelling approach that takes into account lateral transport of heat, water, and snow and the subsidence of the ground surface due to melting of ground ice. We found that wetter conditions have a destabilizing effect on the ice wedges and associated our simulation results with observations from the study area.
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, https://doi.org/10.5194/essd-11-261-2019, https://doi.org/10.5194/essd-11-261-2019, 2019
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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, https://doi.org/10.5194/essd-11-221-2019, https://doi.org/10.5194/essd-11-221-2019, 2019
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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.
Kjetil S. Aas, Léo Martin, Jan Nitzbon, Moritz Langer, Julia Boike, Hanna Lee, Terje K. Berntsen, and Sebastian Westermann
The Cryosphere, 13, 591–609, https://doi.org/10.5194/tc-13-591-2019, https://doi.org/10.5194/tc-13-591-2019, 2019
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Many permafrost landscapes contain large amounts of excess ground ice, which gives rise to small-scale elevation differences. This results in lateral fluxes of snow, water, and heat, which we investigate and show how it can be accounted for in large-scale models. Using a novel model technique which can account for these differences, we are able to model both the current state of permafrost and how these landscapes change as permafrost thaws, in a way that could not previously be achieved.
Gerhard Krinner, Chris Derksen, Richard Essery, Mark Flanner, Stefan Hagemann, Martyn Clark, Alex Hall, Helmut Rott, Claire Brutel-Vuilmet, Hyungjun Kim, Cécile B. Ménard, Lawrence Mudryk, Chad Thackeray, Libo Wang, Gabriele Arduini, Gianpaolo Balsamo, Paul Bartlett, Julia Boike, Aaron Boone, Frédérique Chéruy, Jeanne Colin, Matthias Cuntz, Yongjiu Dai, Bertrand Decharme, Jeff Derry, Agnès Ducharne, Emanuel Dutra, Xing Fang, Charles Fierz, Josephine Ghattas, Yeugeniy Gusev, Vanessa Haverd, Anna Kontu, Matthieu Lafaysse, Rachel Law, Dave Lawrence, Weiping Li, Thomas Marke, Danny Marks, Martin Ménégoz, Olga Nasonova, Tomoko Nitta, Masashi Niwano, John Pomeroy, Mark S. Raleigh, Gerd Schaedler, Vladimir Semenov, Tanya G. Smirnova, Tobias Stacke, Ulrich Strasser, Sean Svenson, Dmitry Turkov, Tao Wang, Nander Wever, Hua Yuan, Wenyan Zhou, and Dan Zhu
Geosci. Model Dev., 11, 5027–5049, https://doi.org/10.5194/gmd-11-5027-2018, https://doi.org/10.5194/gmd-11-5027-2018, 2018
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This paper provides an overview of a coordinated international experiment to determine the strengths and weaknesses in how climate models treat snow. The models will be assessed at point locations using high-quality reference measurements and globally using satellite-derived datasets. How well climate models simulate snow-related processes is important because changing snow cover is an important part of the global climate system and provides an important freshwater resource for human use.
Isabelle Gouttevin, Moritz Langer, Henning Löwe, Julia Boike, Martin Proksch, and Martin Schneebeli
The Cryosphere, 12, 3693–3717, https://doi.org/10.5194/tc-12-3693-2018, https://doi.org/10.5194/tc-12-3693-2018, 2018
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Snow insulates the ground from the cold air in the Arctic winter, majorly affecting permafrost. This insulation depends on snow characteristics and is poorly quantified. Here, we characterize it at a carbon-rich permafrost site, using a recent technique that retrieves the 3-D structure of snow and its thermal properties. We adapt a snowpack model enabling the simulation of this insulation over a whole winter. We estimate that local snow variations induce up to a 6 °C spread in soil temperatures.
Julia Boike, Inge Juszak, Stephan Lange, Sarah Chadburn, Eleanor Burke, Pier Paul Overduin, Kurt Roth, Olaf Ippisch, Niko Bornemann, Lielle Stern, Isabelle Gouttevin, Ernst Hauber, and Sebastian Westermann
Earth Syst. Sci. Data, 10, 355–390, https://doi.org/10.5194/essd-10-355-2018, https://doi.org/10.5194/essd-10-355-2018, 2018
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A 20-year data record from the Bayelva site at Ny-Ålesund, Svalbard, is presented on meteorology, energy balance components, surface and subsurface observations. This paper presents the data set, instrumentation, calibration, processing and data quality control. The data show that mean annual, summer and winter soil temperature data from shallow to deeper depths have been warming over the period of record, indicating the degradation and loss of permafrost at this site.
Simon Zwieback, Steven V. Kokelj, Frank Günther, Julia Boike, Guido Grosse, and Irena Hajnsek
The Cryosphere, 12, 549–564, https://doi.org/10.5194/tc-12-549-2018, https://doi.org/10.5194/tc-12-549-2018, 2018
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We analyse elevation losses at thaw slumps, at which icy sediments are exposed. As ice requires a large amount of energy to melt, one would expect that mass wasting is governed by the available energy. However, we observe very little mass wasting in June, despite the ample energy supply. Also, in summer, mass wasting is not always energy limited. This highlights the importance of other processes, such as the formation of a protective veneer, in shaping mass wasting at sub-seasonal scales.
Kristoffer Aalstad, Sebastian Westermann, Thomas Vikhamar Schuler, Julia Boike, and Laurent Bertino
The Cryosphere, 12, 247–270, https://doi.org/10.5194/tc-12-247-2018, https://doi.org/10.5194/tc-12-247-2018, 2018
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We demonstrate how snow cover data from satellites can be used to constrain estimates of snow distributions at sites in the Arctic. In this effort, we make use of data assimilation to combine the information contained in the snow cover data with a simple snow model. By comparing our snow distribution estimates to independent observations, we find that this method performs favorably. Being modular, this method could be applied to other areas as a component of a larger reanalysis system.
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, https://doi.org/10.5194/bg-14-5143-2017, https://doi.org/10.5194/bg-14-5143-2017, 2017
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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.
Sabrina Marx, Katharina Anders, Sofia Antonova, Inga Beck, Julia Boike, Philip Marsh, Moritz Langer, and Bernhard Höfle
Earth Surf. Dynam. Discuss., https://doi.org/10.5194/esurf-2017-49, https://doi.org/10.5194/esurf-2017-49, 2017
Revised manuscript has not been submitted
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Global climate warming causes permafrost to warm and thaw, and, consequently, to release the carbon into the atmosphere. Terrestrial laser scanning is evaluated and current methods are extended in the context of monitoring subsidence in Arctic permafrost regions. The extracted information is important to gain a deeper understanding of permafrost-related subsidence processes and provides highly accurate ground-truth data which is necessary for further developing area-wide monitoring methods.
Sebastian Westermann, Maria Peter, Moritz Langer, Georg Schwamborn, Lutz Schirrmeister, Bernd Etzelmüller, and Julia Boike
The Cryosphere, 11, 1441–1463, https://doi.org/10.5194/tc-11-1441-2017, https://doi.org/10.5194/tc-11-1441-2017, 2017
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We demonstrate a remote-sensing-based scheme estimating the evolution of ground temperature and active layer thickness by means of a ground thermal model. A comparison to in situ observations from the Lena River delta in Siberia indicates that the model is generally capable of reproducing the annual temperature regime and seasonal thawing of the ground. The approach could hence be a first step towards remote detection of ground thermal conditions in permafrost areas.
Sina Muster, Kurt Roth, Moritz Langer, Stephan Lange, Fabio Cresto Aleina, Annett Bartsch, Anne Morgenstern, Guido Grosse, Benjamin Jones, A. Britta K. Sannel, Ylva Sjöberg, Frank Günther, Christian Andresen, Alexandra Veremeeva, Prajna R. Lindgren, Frédéric Bouchard, Mark J. Lara, Daniel Fortier, Simon Charbonneau, Tarmo A. Virtanen, Gustaf Hugelius, Juri Palmtag, Matthias B. Siewert, William J. Riley, Charles D. Koven, and Julia Boike
Earth Syst. Sci. Data, 9, 317–348, https://doi.org/10.5194/essd-9-317-2017, https://doi.org/10.5194/essd-9-317-2017, 2017
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Waterbodies are abundant in Arctic permafrost lowlands. Most waterbodies are ponds with a surface area smaller than 100 x 100 m. The Permafrost Region Pond and Lake Database (PeRL) for the first time maps ponds as small as 10 x 10 m. PeRL maps can be used to document changes both by comparing them to historical and future imagery. The distribution of waterbodies in the Arctic is important to know in order to manage resources in the Arctic and to improve climate predictions in the Arctic.
Amund F. Borge, Sebastian Westermann, Ingvild Solheim, and Bernd Etzelmüller
The Cryosphere, 11, 1–16, https://doi.org/10.5194/tc-11-1-2017, https://doi.org/10.5194/tc-11-1-2017, 2017
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Palsas and peat plateaus are permafrost landforms in subarctic mires which constitute sensitive ecosystems with strong significance for vegetation, wildlife, hydrology and carbon cycle. We have systematically mapped the occurrence of palsas and peat plateaus in northern Norway by interpretation of aerial images from the 1950s until today. The results show that about half of the area of palsas and peat plateaus has disappeared due to lateral erosion and melting of ground ice in the last 50 years.
Kjersti Gisnås, Sebastian Westermann, Thomas Vikhamar Schuler, Kjetil Melvold, and Bernd Etzelmüller
The Cryosphere, 10, 1201–1215, https://doi.org/10.5194/tc-10-1201-2016, https://doi.org/10.5194/tc-10-1201-2016, 2016
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In wind exposed areas snow redistribution results in large spatial variability in ground temperatures. In these areas, the ground temperature of a grid cell must be determined based on the distribution, and not the average, of snow depths. We employ distribution functions of snow in a regional permafrost model, showing highly improved representation of ground temperatures. By including snow distributions, we find the permafrost area to be nearly twice as large as what is modelled without.
Fabian Beermann, Moritz Langer, Sebastian Wetterich, Jens Strauss, Julia Boike, Claudia Fiencke, Lutz Schirrmeister, Eva-Maria Pfeiffer, and Lars Kutzbach
Biogeosciences Discuss., https://doi.org/10.5194/bg-2016-117, https://doi.org/10.5194/bg-2016-117, 2016
Revised manuscript not accepted
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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.
S. Westermann, M. Langer, J. Boike, M. Heikenfeld, M. Peter, B. Etzelmüller, and G. Krinner
Geosci. Model Dev., 9, 523–546, https://doi.org/10.5194/gmd-9-523-2016, https://doi.org/10.5194/gmd-9-523-2016, 2016
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Thawing of permafrost is governed by a complex interplay of different processes, of which only conductive heat transfer is taken into account in most model studies. We present a new land-surface scheme designed for permafrost applications, CryoGrid 3, which constitutes a flexible platform to explore new parameterizations for a range of permafrost processes.
J. Boike, C. Georgi, G. Kirilin, S. Muster, K. Abramova, I. Fedorova, A. Chetverova, M. Grigoriev, N. Bornemann, and M. Langer
Biogeosciences, 12, 5941–5965, https://doi.org/10.5194/bg-12-5941-2015, https://doi.org/10.5194/bg-12-5941-2015, 2015
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We show that lakes in northern Siberia are very efficient with respect to energy absorption and mixing using measurements as well as numerical modeling. We show that (i) the lakes receive substantial energy for warming from net short-wave radiation; (ii) convective mixing occurs beneath the ice cover, follow beneath the ice cover, following ice break-up, summer, and fall (iii) modeling suggests that the annual mean net heat flux across the bottom sediment boundary is approximately zero.
I. Beck, R. Ludwig, M. Bernier, T. Strozzi, and J. Boike
Earth Surf. Dynam., 3, 409–421, https://doi.org/10.5194/esurf-3-409-2015, https://doi.org/10.5194/esurf-3-409-2015, 2015
S. E. Chadburn, E. J. Burke, R. L. H. Essery, J. Boike, M. Langer, M. Heikenfeld, P. M. Cox, and P. Friedlingstein
The Cryosphere, 9, 1505–1521, https://doi.org/10.5194/tc-9-1505-2015, https://doi.org/10.5194/tc-9-1505-2015, 2015
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In this paper we use a global land-surface model to study the dynamics of Arctic permafrost. We examine the impact of new and improved processes in the model, namely soil depth and resolution, organic soils, moss and the representation of snow. These improvements make the simulated soil temperatures and thaw depth significantly more realistic. Simulations under future climate scenarios show that permafrost thaws more slowly in the new model version, but still a large amount is lost by 2100.
A. Ekici, S. Chadburn, N. Chaudhary, L. H. Hajdu, A. Marmy, S. Peng, J. Boike, E. Burke, A. D. Friend, C. Hauck, G. Krinner, M. Langer, P. A. Miller, and C. Beer
The Cryosphere, 9, 1343–1361, https://doi.org/10.5194/tc-9-1343-2015, https://doi.org/10.5194/tc-9-1343-2015, 2015
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This paper compares the performance of different land models in estimating soil thermal regimes at distinct cold region landscape types. Comparing models with different processes reveal the importance of surface insulation (snow/moss layer) and soil internal processes (heat/water transfer). The importance of model processes also depend on site conditions such as high/low snow cover, dry/wet soil types.
S. Westermann, T. I. Østby, K. Gisnås, T. V. Schuler, and B. Etzelmüller
The Cryosphere, 9, 1303–1319, https://doi.org/10.5194/tc-9-1303-2015, https://doi.org/10.5194/tc-9-1303-2015, 2015
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We use remotely sensed land surface temperature and land cover in conjunction with air temperature and snowfall from a reanalysis product as input for a simple permafrost model. The scheme is applied to the permafrost regions bordering the North Atlantic. A comparison with ground temperatures in boreholes suggests a modeling accuracy of 2 to 2.5 °C.
T. Schneider von Deimling, G. Grosse, J. Strauss, L. Schirrmeister, A. Morgenstern, S. Schaphoff, M. Meinshausen, and J. Boike
Biogeosciences, 12, 3469–3488, https://doi.org/10.5194/bg-12-3469-2015, https://doi.org/10.5194/bg-12-3469-2015, 2015
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We have modelled the carbon release from thawing permafrost soils under various scenarios of future warming. Our results suggests that up to about 140Pg of carbon could be released under strong warming by end of the century. We have shown that abrupt thaw processes under thermokarst lakes can unlock large amounts of perennially frozen carbon stored in deep deposits (which extend many metres into the soil).
S. Chadburn, E. Burke, R. Essery, J. Boike, M. Langer, M. Heikenfeld, P. Cox, and P. Friedlingstein
Geosci. Model Dev., 8, 1493–1508, https://doi.org/10.5194/gmd-8-1493-2015, https://doi.org/10.5194/gmd-8-1493-2015, 2015
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Permafrost, ground that is frozen for 2 or more years, is found extensively in the Arctic. It stores large quantities of carbon, which may be released under climate warming, so it is important to include it in climate models. Here we improve the representation of permafrost in a climate model land-surface scheme, both in the numerical representation of soil and snow, and by adding the effects of organic soils and moss. Site simulations show significantly improved soil temperature and thaw depth.
S. Westermann, B. Elberling, S. Højlund Pedersen, M. Stendel, B. U. Hansen, and G. E. Liston
The Cryosphere, 9, 719–735, https://doi.org/10.5194/tc-9-719-2015, https://doi.org/10.5194/tc-9-719-2015, 2015
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The development of ground temperatures in permafrost areas is influenced by many factors varying on different spatial and temporal scales. We present numerical simulations of ground temperatures for the Zackenberg valley in NE Greenland, which take into account the spatial variability of snow depths, surface and ground properties at a scale of 10m. The ensemble of the model grid cells suggests a spatial variability of annual average ground temperatures of up to 5°C.
M. Langer, S. Westermann, K. Walter Anthony, K. Wischnewski, and J. Boike
Biogeosciences, 12, 977–990, https://doi.org/10.5194/bg-12-977-2015, https://doi.org/10.5194/bg-12-977-2015, 2015
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Methane production rates of Arctic ponds during the freezing period within a typical tundra landscape in northern Siberia are presented. Production rates were inferred by inverse modeling based on measured methane concentrations in the ice cover. Results revealed marked differences in early winter methane production among ponds showing different stages of shore degradation. This suggests that shore erosion can increase methane production of Arctic ponds by 2 to 3 orders of magnitude.
I. Fedorova, A. Chetverova, D. Bolshiyanov, A. Makarov, J. Boike, B. Heim, A. Morgenstern, P. P. Overduin, C. Wegner, V. Kashina, A. Eulenburg, E. Dobrotina, and I. Sidorina
Biogeosciences, 12, 345–363, https://doi.org/10.5194/bg-12-345-2015, https://doi.org/10.5194/bg-12-345-2015, 2015
K. Gisnås, S. Westermann, T. V. Schuler, T. Litherland, K. Isaksen, J. Boike, and B. Etzelmüller
The Cryosphere, 8, 2063–2074, https://doi.org/10.5194/tc-8-2063-2014, https://doi.org/10.5194/tc-8-2063-2014, 2014
S. Yi, K. Wischnewski, M. Langer, S. Muster, and J. Boike
Geosci. Model Dev., 7, 1671–1689, https://doi.org/10.5194/gmd-7-1671-2014, https://doi.org/10.5194/gmd-7-1671-2014, 2014
S. Westermann, T. V. Schuler, K. Gisnås, and B. Etzelmüller
The Cryosphere, 7, 719–739, https://doi.org/10.5194/tc-7-719-2013, https://doi.org/10.5194/tc-7-719-2013, 2013
Related subject area
Biogeochemistry: Air - Land Exchange
Versatile soil gas concentration and isotope monitoring: optimization and integration of novel soil gas probes with online trace gas detection
On the impact of canopy model complexity on simulated carbon, water, and solar-induced chlorophyll fluorescence fluxes
Mercury accumulation in leaves of different plant types – the significance of tissue age and specific leaf area
Isolation of subpollen particles (SPPs) of birch: SPPs are potential carriers of ice nucleating macromolecules
Physiological and climate controls on foliar mercury uptake by European tree species
Choosing an optimal β factor for relaxed eddy accumulation applications across vegetated and non-vegetated surfaces
Bioaerosols in the Amazon rain forest: temporal variations and vertical profiles of Eukarya, Bacteria, and Archaea
Effects of soil water content on carbon sink strength in an alpine swamp meadow of the northeastern Qinghai-Tibet Plateau
Ice nucleation by viruses and their potential for cloud glaciation
Representativeness assessment of the pan-Arctic eddy-covariance site network, and optimized future enhancements
Carbon dioxide fluxes and carbon balance of an agricultural grassland in southern Finland
Sun-induced fluorescence and near-infrared reflectance of vegetation track the seasonal dynamics of gross primary production over Africa
Measurement and modelling of the dynamics of NH3 surface–atmosphere exchange over the Amazonian rainforest
Isoprene and monoterpene emissions from alder, aspen and spruce short-rotation forest plantations in the United Kingdom
Winter atmospheric nutrient and pollutant deposition on Western Sayan Mountain lakes (Siberia)
Methane efflux from an American bison herd
Technical note: Inexpensive modification of Exetainers for the reliable storage of trace-level hydrogen and carbon monoxide gas samples
Ideas and perspectives: Emerging contours of a dynamic exogenous kerogen cycle
A climate-dependent global model of ammonia emissions from chicken farming
Calculating canopy stomatal conductance from eddy covariance measurements, in light of the energy budget closure problem
Decoupling of a Douglas fir canopy: a look into the subcanopy with continuous vertical temperature profiles
Variations in diurnal and seasonal net ecosystem carbon dioxide exchange in a semiarid sandy grassland ecosystem in China's Horqin Sandy Land
Biogenic volatile organic compound ambient mixing ratios and emission rates in the Alaskan Arctic tundra
Surfaces of silver birch (Betula pendula) are sources of biological ice nuclei: in vivo and in situ investigations
Ideas and perspectives: enhancing the impact of the FLUXNET network of eddy covariance sites
Evapotranspiration over agroforestry sites in Germany
Forest-atmosphere exchange of reactive nitrogen in a low polluted area – temporal dynamics and annual budgets
OH reactivity from the emissions of different tree species: investigating the missing reactivity in a boreal forest
Vegetation influence and environmental controls on greenhouse gas fluxes from a drained thermokarst lake in the western Canadian Arctic
Examining the link between vegetation leaf area and land–atmosphere exchange of water, energy, and carbon fluxes using FLUXNET data
CloudRoots: integration of advanced instrumental techniques and process modelling of sub-hourly and sub-kilometre land–atmosphere interactions
Environmental controls on ecosystem-scale cold-season methane and carbon dioxide fluxes in an Arctic tundra ecosystem
Distinguishing between early- and late-covering crops in the land surface model Noah-MP: impact on simulated surface energy fluxes and temperature
A robust data cleaning procedure for eddy covariance flux measurements
Scaling carbon fluxes from eddy covariance sites to globe: synthesis and evaluation of the FLUXCOM approach
Leveraging the signature of heterotrophic respiration on atmospheric CO2 for model benchmarking
Estimating causal networks in biosphere–atmosphere interaction with the PCMCI approach
A double peak in the seasonality of California's photosynthesis as observed from space
Nitrogen use efficiency and N2O and NH3 losses attributed to three fertiliser types applied to an intensively managed silage crop
Biogenic isoprenoid emissions under drought stress: different responses for isoprene and terpenes
Insights from mercury stable isotopes on terrestrial–atmosphere exchange of Hg(0) in the Arctic tundra
Reviews and syntheses: Turning the challenges of partitioning ecosystem evaporation and transpiration into opportunities
El Niño–Southern Oscillation (ENSO) event reduces CO2 uptake of an Indonesian oil palm plantation
Carbon–water flux coupling under progressive drought
Reviews and syntheses: influences of landscape structure and land uses on local to regional climate and air quality
Identification of secondary fatty alcohols in atmospheric aerosols in temperate forests
Modelling land–atmosphere daily exchanges of NO, NH3, and CO2 in a semi-arid grazed ecosystem in Senegal
Simulating the atmospheric CO2 concentration across the heterogeneous landscape of Denmark using a coupled atmosphere–biosphere mesoscale model system
Evaluating multi-year, multi-site data on the energy balance closure of eddy-covariance flux measurements at cropland sites in southwestern Germany
Interpreting eddy covariance data from heterogeneous Siberian tundra: land-cover-specific methane fluxes and spatial representativeness
Juliana Gil-Loaiza, Joseph R. Roscioli, Joanne H. Shorter, Till H. M. Volkmann, Wei-Ren Ng, Jordan E. Krechmer, and Laura K. Meredith
Biogeosciences, 19, 165–185, https://doi.org/10.5194/bg-19-165-2022, https://doi.org/10.5194/bg-19-165-2022, 2022
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We evaluated a new diffusive soil probe integrated with high-resolution gas analyzers to measure soil gases in real time at a centimeter scale. Using columns with simple silica and soil, we captured changes in carbon dioxide (CO2), volatile organic compounds (VOCs), and nitrous oxide (N2O) with its isotopes to distinguish potential nutrient sources and microbial metabolism. This approach will advance the use of soil gases as important signals to understand and monitor soil fertility and health.
Yujie Wang and Christian Frankenberg
Biogeosciences, 19, 29–45, https://doi.org/10.5194/bg-19-29-2022, https://doi.org/10.5194/bg-19-29-2022, 2022
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Modeling vegetation canopy is important in predicting whether the land remains a carbon sink to mitigate climate change in the near future. Vegetation canopy model complexity, however, impacts the model-predicted carbon and water fluxes as well as canopy fluorescence, even if the same suite of model inputs is used. Given the biases caused by canopy model complexity, we recommend not misusing parameters inverted using different models or assumptions.
Håkan Pleijel, Jenny Klingberg, Michelle Nerentorp, Malin C. Broberg, Brigitte Nyirambangutse, John Munthe, and Göran Wallin
Biogeosciences, 18, 6313–6328, https://doi.org/10.5194/bg-18-6313-2021, https://doi.org/10.5194/bg-18-6313-2021, 2021
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Mercury is a problematic metal in the environment. It is crucial to understand the Hg circulation in ecosystems. We explored the mercury concentration in foliage from a diverse set of plants, locations and sampling periods to study the accumulation of Hg in leaves–needles over time. Mercury was always higher in older tissue: in broadleaved trees, conifers and wheat. Specific leaf area, the leaf area per unit leaf mass, turned out to be critical for Hg accumulation in leaves–needles.
Julia Burkart, Jürgen Gratzl, Teresa M. Seifried, Paul Bieber, and Hinrich Grothe
Biogeosciences, 18, 5751–5765, https://doi.org/10.5194/bg-18-5751-2021, https://doi.org/10.5194/bg-18-5751-2021, 2021
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Extracts of birch pollen grains are known to be ice nucleation active and thus impact cloud formation and climate. In this study we develop an extraction method to separate subpollen particles from ice nucleating macromolecules. Our results thereby illustrate that ice nucleating macromolecules can be washed off the subpollen particles and that the ice activity is linked to the presence of proteins.
Lena Wohlgemuth, Pasi Rautio, Bernd Ahrends, Alexander Russ, Lars Vesterdal, Peter Waldner, Volkmar Timmermann, Nadine Eickenscheidt, Alfred Fürst, Martin Greve, Peter Roskams, Anne Thimonier, Manuel Nicolas, Anna Kowalska, Morten Ingerslev, Päivi Merilä, Sue Benham, Carmen Iacoban, Günter Hoch, Christine Alewell, and Martin Jiskra
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-239, https://doi.org/10.5194/bg-2021-239, 2021
Revised manuscript accepted for BG
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Gaseous mercury is present in the atmosphere all over the globe. During the growing season, plants take up mercury from the air in a similar way as CO2. We investigated, which factors impact this vegetational mercury uptake by analyzing a large dataset of mercury uptake rates by forest trees in Europe. As a result, we conclude, that mercury uptake is foremost controlled by tree-intrinsic traits like physiological activity, but also by climatic factors like dry conditions in the air and in soils.
Teresa Vogl, Amy Hrdina, and Christoph K. Thomas
Biogeosciences, 18, 5097–5115, https://doi.org/10.5194/bg-18-5097-2021, https://doi.org/10.5194/bg-18-5097-2021, 2021
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The relaxed eddy accumulation technique is a method used for measuring fluxes of chemical species in the atmosphere. It relies on a proportionality factor, β, which can be determined using different methods. Also, different techniques for sampling can be used by only drawing air into the measurement system when vertical wind velocity exceeds a certain threshold. We compare different ways to obtain β and different threshold techniques to direct flux measurements for three different sites.
Maria Prass, Meinrat O. Andreae, Alessandro C. de Araùjo, Paulo Artaxo, Florian Ditas, Wolfgang Elbert, Jan-David Förster, Marco Aurélio Franco, Isabella Hrabe de Angelis, Jürgen Kesselmeier, Thomas Klimach, Leslie Ann Kremper, Eckhard Thines, David Walter, Jens Weber, Bettina Weber, Bernhard M. Fuchs, Ulrich Pöschl, and Christopher Pöhlker
Biogeosciences, 18, 4873–4887, https://doi.org/10.5194/bg-18-4873-2021, https://doi.org/10.5194/bg-18-4873-2021, 2021
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Bioaerosols in the atmosphere over the Amazon rain forest were analyzed by molecular biological staining and microscopy. Eukaryotic, bacterial, and archaeal aerosols were quantified in time series and altitude profiles which exhibited clear differences in number concentrations and vertical distributions. Our results provide insights into the sources and dispersion of different Amazonian bioaerosol types as a basis for a better understanding of biosphere–atmosphere interactions.
Junqi Wei, Xiaoyan Li, Lei Liu, Torben Røjle Christensen, Zhiyun Jiang, Yujun Ma, Xiuchen Wu, Hongyun Yao, and Efrén López-Blanco
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-193, https://doi.org/10.5194/bg-2021-193, 2021
Revised manuscript accepted for BG
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Although water availability has been linked to the response of ecosystem carbon (C) sink/source to climate warming, the mechanisms by which C uptake responds to soil moisture remain unclear. We explored how soil water and other environmental drivers modulate net C uptake in an alpine swamp meadow. Results reveal that nearly saturated soil conditions during warm seasons can help to maintain lower ecosystem respiration and therefore enhance the C sequestration capacity in this alpine swamp meadow.
Michael P. Adams, Nina S. Atanasova, Svetlana Sofieva, Janne Ravantti, Aino Heikkinen, Zoé Brasseur, Jonathan Duplissy, Dennis H. Bamford, and Benjamin J. Murray
Biogeosciences, 18, 4431–4444, https://doi.org/10.5194/bg-18-4431-2021, https://doi.org/10.5194/bg-18-4431-2021, 2021
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The formation of ice in clouds is critically important for the planet's climate. Hence, we need to know which aerosol types nucleate ice and how effectively they do so. Here we show that virus particles, with a range of architectures, nucleate ice when immersed in supercooled water. However, we also show that they only make a minor contribution to the ice-nucleating particle population in the terrestrial atmosphere, but we cannot rule them out as being important in the marine environment.
Martijn Pallandt, Jitendra Kumar, Marguerite Mauritz, Edward Schuur, Anna-Maria Virkkala, Gerardo Celis, Forrest Hoffman, and Mathias Göckede
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-133, https://doi.org/10.5194/bg-2021-133, 2021
Revised manuscript accepted for BG
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Thawing of Arctic permafrost soils could trigger the release of vast amounts of carbon to the atmosphere, thus enhance climate change. Our study investigated how well the current network of eddy-covariance sites, a technique to monitor greenhouse gas exchange at local scales, captures pan-Arctic flux patterns. We identified large coverage gaps, e.g. in Siberia, but also demonstrated that a targeted addition of relatively few sites can significantly improve network performance.
Laura Heimsch, Annalea Lohila, Juha-Pekka Tuovinen, Henriikka Vekuri, Jussi Heinonsalo, Olli Nevalainen, Mika Korkiakoski, Jari Liski, Tuomas Laurila, and Liisa Kulmala
Biogeosciences, 18, 3467–3483, https://doi.org/10.5194/bg-18-3467-2021, https://doi.org/10.5194/bg-18-3467-2021, 2021
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CO2 and H2O fluxes were measured at a newly established eddy covariance site in southern Finland for 2 years from 2018 to 2020. This agricultural grassland site focuses on the conversion from intensive towards more sustainable agricultural management. The first summer experienced prolonged dry periods, and notably larger fluxes were observed in the second summer. The field acted as a net carbon sink during both study years.
Anteneh Getachew Mengistu, Gizaw Mengistu Tsidu, Gerbrand Koren, Maurits L. Kooreman, K. Folkert Boersma, Torbern Tagesson, Jonas Ardö, Yann Nouvellon, and Wouter Peters
Biogeosciences, 18, 2843–2857, https://doi.org/10.5194/bg-18-2843-2021, https://doi.org/10.5194/bg-18-2843-2021, 2021
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In this study, we assess the usefulness of Sun-Induced Fluorescence of Terrestrial Ecosystems Retrieval (SIFTER) data from the GOME-2A instrument and near-infrared reflectance of vegetation (NIRv) from MODIS to capture the seasonality and magnitudes of gross primary production (GPP) derived from six eddy-covariance flux towers in Africa in the overlap years between 2007–2014. We also test the robustness of sun-induced fluoresence and NIRv to compare the seasonality of GPP for the major biomes.
Robbie Ramsay, Chiara F. Di Marco, Mathew R. Heal, Matthias Sörgel, Paulo Artaxo, Meinrat O. Andreae, and Eiko Nemitz
Biogeosciences, 18, 2809–2825, https://doi.org/10.5194/bg-18-2809-2021, https://doi.org/10.5194/bg-18-2809-2021, 2021
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The exchange of the gas ammonia between the atmosphere and the surface is an important biogeochemical process, but little is known of this exchange for certain ecosystems, such as the Amazon rainforest. This study took measurements of ammonia exchange over an Amazon rainforest site and subsequently modelled the observed deposition and emission patterns. We observed emissions of ammonia from the rainforest, which can be simulated accurately by using a canopy resistance modelling approach.
Gemma Purser, Julia Drewer, Mathew R. Heal, Robert A. S. Sircus, Lara K. Dunn, and James I. L. Morison
Biogeosciences, 18, 2487–2510, https://doi.org/10.5194/bg-18-2487-2021, https://doi.org/10.5194/bg-18-2487-2021, 2021
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Short-rotation forest plantations could help reduce greenhouse gases but can emit biogenic volatile organic compounds. Emissions were measured at a plantation trial in Scotland. Standardised emissions of isoprene from foliage were higher from hybrid aspen than from Sitka spruce and low from Italian alder. Emissions of total monoterpene were lower. The forest floor was only a small source. Model estimates suggest an SRF expansion of 0.7 Mha could increase total UK emissions between < 1 %–35 %.
Daniel Diaz-de-Quijano, Aleksander Vladimirovich Ageev, Elena Anatolevna Ivanova, and Olesia Valerevna Anishchenko
Biogeosciences, 18, 1601–1618, https://doi.org/10.5194/bg-18-1601-2021, https://doi.org/10.5194/bg-18-1601-2021, 2021
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Winter atmospheric nitrogen (N) and phosphorus (P) depositions were measured for the first time in the Western Sayan Mountains (Siberia). The low and very low atmospheric N and P depositions could be responsible for the observed lake phytoplankton N–P colimitation. We hypothesize that slight imbalances in the nutrient deposition, as expected in the context of global change (climate, forest fires and anthropogenic nitrogen emissions), could have important effects on the ecology of these lakes.
Paul C. Stoy, Adam A. Cook, John E. Dore, Natascha Kljun, William Kleindl, E. N. Jack Brookshire, and Tobias Gerken
Biogeosciences, 18, 961–975, https://doi.org/10.5194/bg-18-961-2021, https://doi.org/10.5194/bg-18-961-2021, 2021
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The reintroduction of American bison creates multiple environmental benefits. Ruminants like bison also emit methane – a potent greenhouse gas – to the atmosphere, which has not been measured to date in a field setting. We measured methane efflux from an American bison herd during winter using eddy covariance. Automated cameras were used to approximate their location to calculate per-animal flux. From the measurements, bison do not emit more methane than the cattle they often replace.
Philipp A. Nauer, Eleonora Chiri, Thanavit Jirapanjawat, Chris Greening, and Perran L. M. Cook
Biogeosciences, 18, 729–737, https://doi.org/10.5194/bg-18-729-2021, https://doi.org/10.5194/bg-18-729-2021, 2021
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Hydrogen (H2) and carbon monoxide (CO) are atmospheric trace gases cycled via microbial metabolisms. We observed strong H2 and CO contamination from rubber septa used to seal common gas sample storage vials. Here we propose a simple and inexpensive modification of such vials to allow reliable storage of H2, CO and methane trace-gas samples for timescales of weeks to months, thus enabling extensive field campaigns to investigate H2 and CO biogeochemistry in remote areas.
Thomas M. Blattmann
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-4, https://doi.org/10.5194/bg-2021-4, 2021
Revised manuscript accepted for BG
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This work enunciates the possibility of kerogen oxidation as a major driver of atmospheric CO2 increase in the wake of glacial episodes. This hypothesis is substantiated by several lines of independent evidence synthesized in this contribution. The author hypothesizes that the deglaciation of kerogen-rich lithologies in western Canada contributed majorly to the characteristic deglacial increase in atmospheric CO2.
Jize Jiang, David S. Stevenson, Aimable Uwizeye, Giuseppe Tempio, and Mark A. Sutton
Biogeosciences, 18, 135–158, https://doi.org/10.5194/bg-18-135-2021, https://doi.org/10.5194/bg-18-135-2021, 2021
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Ammonia is a key water and air pollutant and impacts human health and climate change. Ammonia emissions mainly originate from agriculture. We find that chicken agriculture contributes to large ammonia emissions, especially in hot and wet regions. These emissions can be greatly affected by the local environment, i.e. temperature and humidity, and also by human management. We develop a model that suggests ammonia emissions from chicken farming are likely to increase under a warming climate.
Richard Wehr and Scott R. Saleska
Biogeosciences, 18, 13–24, https://doi.org/10.5194/bg-18-13-2021, https://doi.org/10.5194/bg-18-13-2021, 2021
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Water and carbon exchange between plants and the atmosphere is governed by stomata: adjustable pores in the surfaces of leaves. The combined gas conductance of all the stomata in a canopy has long been estimated using an equation that is shown here to be systematically incorrect because it relies on measurements that are generally inadequate. An alternative approach is shown to be more accurate in all probable scenarios and to imply different responses of stomatal conductance to the environment.
Bart Schilperoort, Miriam Coenders-Gerrits, César Jiménez Rodríguez, Christiaan van der Tol, Bas van de Wiel, and Hubert Savenije
Biogeosciences, 17, 6423–6439, https://doi.org/10.5194/bg-17-6423-2020, https://doi.org/10.5194/bg-17-6423-2020, 2020
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With distributed temperature sensing (DTS) we measured a vertical temperature profile in a forest, from the forest floor to above the treetops. Using this temperature profile we can see which parts of the forest canopy are colder (thus more dense) or warmer (and less dense) and study the effect this has on the suppression of turbulent mixing. This can be used to improve our knowledge of the interaction between the atmosphere and forests and improve carbon dioxide flux measurements over forests.
Yayi Niu, Yuqiang Li, Hanbo Yun, Xuyang Wang, Xiangwen Gong, Yulong Duan, and Jing Liu
Biogeosciences, 17, 6309–6326, https://doi.org/10.5194/bg-17-6309-2020, https://doi.org/10.5194/bg-17-6309-2020, 2020
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We report the results from continuous year-round CO2 observations from a sandy grassland in the Horqin Sandy Land using the eddy covariance technique. To quantify the diurnal, seasonal, and annual variation in net ecosystem CO2 exchange, gross primary productivity, and ecosystem respiration and to identify the different scales of environmental factors and the underlying mechanisms, we also explored how the annual precipitation affects the net ecosystem CO2 exchange and its components.
Hélène Angot, Katelyn McErlean, Lu Hu, Dylan B. Millet, Jacques Hueber, Kaixin Cui, Jacob Moss, Catherine Wielgasz, Tyler Milligan, Damien Ketcherside, M. Syndonia Bret-Harte, and Detlev Helmig
Biogeosciences, 17, 6219–6236, https://doi.org/10.5194/bg-17-6219-2020, https://doi.org/10.5194/bg-17-6219-2020, 2020
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We report biogenic volatile organic compounds (BVOCs) ambient levels and emission rates from key vegetation species in the Alaskan arctic tundra, providing a new data set to further constrain isoprene chemistry under low NOx conditions in models. We add to the growing body of evidence that climate-induced changes in the vegetation composition will significantly affect the BVOC emission potential of the tundra, with implications for atmospheric oxidation processes and climate feedbacks.
Teresa M. Seifried, Paul Bieber, Laura Felgitsch, Julian Vlasich, Florian Reyzek, David G. Schmale III, and Hinrich Grothe
Biogeosciences, 17, 5655–5667, https://doi.org/10.5194/bg-17-5655-2020, https://doi.org/10.5194/bg-17-5655-2020, 2020
Dario Papale
Biogeosciences, 17, 5587–5598, https://doi.org/10.5194/bg-17-5587-2020, https://doi.org/10.5194/bg-17-5587-2020, 2020
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FLUXNET is a large, bottom-up, self-coordinated network of sites. It provided ecosystem–atmosphere greenhouse gas fluxes from stations around the world that were used as bases for a large number of publications and studies. Today many applications require recent updates on the data to track more closely the ecosystem responses to climate change and link ground data with satellite programs. For this reason, a new organization of FLUXNET is needed, keeping as its target the FAIR principles.
Christian Markwitz, Alexander Knohl, and Lukas Siebicke
Biogeosciences, 17, 5183–5208, https://doi.org/10.5194/bg-17-5183-2020, https://doi.org/10.5194/bg-17-5183-2020, 2020
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Agroforestry has been shown to alter the microclimate and to lead to higher carbon sequestration above ground and in the soil. In this study, we investigated the impact of agroforestry systems on system-scale evapotranspiration (ET) due to concerns about increased water losses to the atmosphere. Results showed small differences in annual sums of ET over agroforestry relative to monoculture systems, indicating that agroforestry in Germany can be a land use alternative to monoculture agriculture.
Pascal Wintjen, Frederik Schrader, Martijn Schaap, Burkhard Beudert, and Christian Brümmer
Biogeosciences Discuss., https://doi.org/10.5194/bg-2020-364, https://doi.org/10.5194/bg-2020-364, 2020
Revised manuscript accepted for BG
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Eddy covariance flux measurements of total reactive nitrogen (∑Nr) over a low polluted forest were compared to in-situ modeled fluxes, results from a large-scale chemical transport model (CTM), and canopy outflow measurements. Annual dry deposition budgets after 2.5 years of measurements ranged from 4.5 to 7.5 kg N ha−1 a−1, depending on the applied method. Modeled NH3 concentrations were found to be the primary contributor to a mismatch between measured ∑Nr fluxes and those modeled with a CTM.
Arnaud P. Praplan, Toni Tykkä, Simon Schallhart, Virpi Tarvainen, Jaana Bäck, and Heidi Hellén
Biogeosciences, 17, 4681–4705, https://doi.org/10.5194/bg-17-4681-2020, https://doi.org/10.5194/bg-17-4681-2020, 2020
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In this paper, we study emissions of volatile organic compounds (VOCs) from three boreal tree species. Individual compounds are quantified with on-line separation analytical techniques, while the total reactivity of the emissions is measured using a custom-built instrument. On some occasions, in particular when the trees suffer from stress, the total reactivity measured is higher than the sum of the reactivity of individual compounds. This indicates that the threes emit VOCs that remain unknown.
June Skeeter, Andreas Christen, Andrée-Anne Laforce, Elyn Humphreys, and Greg Henry
Biogeosciences, 17, 4421–4441, https://doi.org/10.5194/bg-17-4421-2020, https://doi.org/10.5194/bg-17-4421-2020, 2020
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This study investigates carbon fluxes at Illisarvik, an artificial drained thermokarst lake basin (DTLB) in Canada's Northwest Territories. This is the first carbon balance study in a DTLB outside of Alaska. We used neural networks to identify the factors controlling fluxes and to model the effects of the controlling factors. We discuss the role of vegetation heterogeneity in fluxes, especially of methane, and we show how the carbon fluxes differ from Alaskan DTLBs.
Anne J. Hoek van Dijke, Kaniska Mallick, Martin Schlerf, Miriam Machwitz, Martin Herold, and Adriaan J. Teuling
Biogeosciences, 17, 4443–4457, https://doi.org/10.5194/bg-17-4443-2020, https://doi.org/10.5194/bg-17-4443-2020, 2020
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We investigated the link between the vegetation leaf area index (LAI) and the land–atmosphere exchange of water, energy, and carbon fluxes. We show that the correlation between the LAI and water and energy fluxes depends on the vegetation type and aridity. For carbon fluxes, however, the correlation with the LAI was strong and independent of vegetation and aridity. This study provides insight into when the vegetation LAI can be used to model or extrapolate land–atmosphere fluxes.
Jordi Vilà-Guerau de Arellano, Patrizia Ney, Oscar Hartogensis, Hugo de Boer, Kevin van Diepen, Dzhaner Emin, Geiske de Groot, Anne Klosterhalfen, Matthias Langensiepen, Maria Matveeva, Gabriela Miranda-García, Arnold F. Moene, Uwe Rascher, Thomas Röckmann, Getachew Adnew, Nicolas Brüggemann, Youri Rothfuss, and Alexander Graf
Biogeosciences, 17, 4375–4404, https://doi.org/10.5194/bg-17-4375-2020, https://doi.org/10.5194/bg-17-4375-2020, 2020
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The CloudRoots field experiment has obtained an open comprehensive observational data set that includes soil, plant, and atmospheric variables to investigate the interactions between a heterogeneous land surface and its overlying atmospheric boundary layer, including the rapid perturbations of clouds in evapotranspiration. Our findings demonstrate that in order to understand and represent diurnal variability, we need to measure and model processes from the leaf to the landscape scales.
Dean Howard, Yannick Agnan, Detlev Helmig, Yu Yang, and Daniel Obrist
Biogeosciences, 17, 4025–4042, https://doi.org/10.5194/bg-17-4025-2020, https://doi.org/10.5194/bg-17-4025-2020, 2020
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The Arctic tundra represents a vast store of carbon that may be broken down by microbial activity into greenhouse gases such as CO2 and CH4. Though microbes are less active in winter, the long duration of the cold season makes this period very important for carbon cycling. We show that, under conditions of warmer winter air temperatures and greater snowfall, deeper soils can remain warm enough to sustain significantly enhanced CH4 emission. This could have large implications for future climates.
Kristina Bohm, Joachim Ingwersen, Josipa Milovac, and Thilo Streck
Biogeosciences, 17, 2791–2805, https://doi.org/10.5194/bg-17-2791-2020, https://doi.org/10.5194/bg-17-2791-2020, 2020
Domenico Vitale, Gerardo Fratini, Massimo Bilancia, Giacomo Nicolini, Simone Sabbatini, and Dario Papale
Biogeosciences, 17, 1367–1391, https://doi.org/10.5194/bg-17-1367-2020, https://doi.org/10.5194/bg-17-1367-2020, 2020
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This work describes a data cleaning procedure for the detection of eddy covariance fluxes affected by systematic errors. We believe that the proposed procedure can serve as a basis toward a unified quality control strategy suitable for the centralized data processing pipelines, where the use of completely data-driven and scalable procedures that guarantee high-quality standards and reproducibility of the released products constitutes an essential prerequisite.
Martin Jung, Christopher Schwalm, Mirco Migliavacca, Sophia Walther, Gustau Camps-Valls, Sujan Koirala, Peter Anthoni, Simon Besnard, Paul Bodesheim, Nuno Carvalhais, Frédéric Chevallier, Fabian Gans, Daniel S. Goll, Vanessa Haverd, Philipp Köhler, Kazuhito Ichii, Atul K. Jain, Junzhi Liu, Danica Lombardozzi, Julia E. M. S. Nabel, Jacob A. Nelson, Michael O'Sullivan, Martijn Pallandt, Dario Papale, Wouter Peters, Julia Pongratz, Christian Rödenbeck, Stephen Sitch, Gianluca Tramontana, Anthony Walker, Ulrich Weber, and Markus Reichstein
Biogeosciences, 17, 1343–1365, https://doi.org/10.5194/bg-17-1343-2020, https://doi.org/10.5194/bg-17-1343-2020, 2020
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We test the approach of producing global gridded carbon fluxes based on combining machine learning with local measurements, remote sensing and climate data. We show that we can reproduce seasonal variations in carbon assimilated by plants via photosynthesis and in ecosystem net carbon balance. The ecosystem’s mean carbon balance and carbon flux trends require cautious interpretation. The analysis paves the way for future improvements of the data-driven assessment of carbon fluxes.
Samantha J. Basile, Xin Lin, William R. Wieder, Melannie D. Hartman, and Gretchen Keppel-Aleks
Biogeosciences, 17, 1293–1308, https://doi.org/10.5194/bg-17-1293-2020, https://doi.org/10.5194/bg-17-1293-2020, 2020
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Soil heterotrophic respiration (HR) is an important component of land–atmosphere carbon exchange but is difficult to observe globally. We analyzed the imprint that this flux leaves on atmospheric CO2 using a set of simulations from HR models with common inputs. Models that represent microbial processes are more variable and have stronger temperature sensitivity than those that do not. Our results show that we can use atmospheric CO2 observations to evaluate and improve models of HR.
Christopher Krich, Jakob Runge, Diego G. Miralles, Mirco Migliavacca, Oscar Perez-Priego, Tarek El-Madany, Arnaud Carrara, and Miguel D. Mahecha
Biogeosciences, 17, 1033–1061, https://doi.org/10.5194/bg-17-1033-2020, https://doi.org/10.5194/bg-17-1033-2020, 2020
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Causal inference promises new insight into biosphere–atmosphere interactions using time series only. To understand the behaviour of a specific method on such data, we used artificial and observation-based data. The observed structures are very interpretable and reveal certain ecosystem-specific behaviour, as only a few relevant links remain, in contrast to pure correlation techniques. Thus, causal inference allows to us gain well-constrained insights into processes and interactions.
Alexander J. Turner, Philipp Köhler, Troy S. Magney, Christian Frankenberg, Inez Fung, and Ronald C. Cohen
Biogeosciences, 17, 405–422, https://doi.org/10.5194/bg-17-405-2020, https://doi.org/10.5194/bg-17-405-2020, 2020
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We present the highest resolution solar-induced chlorophyll fluorescence (SIF) dataset from satellite measurements, providing previously unobservable phenomena related to plant photosynthesis. We find a strong correspondence between TROPOMI SIF and AmeriFlux GPP. We then observe a double peak in the seasonality of California's photosynthesis, not seen by traditional vegetation indices (e.g., MODIS). This is further corroborated by EOF/PC analysis.
Nicholas Cowan, Peter Levy, Andrea Moring, Ivan Simmons, Colin Bache, Amy Stephens, Joana Marinheiro, Jocelyn Brichet, Ling Song, Amy Pickard, Connie McNeill, Roseanne McDonald, Juliette Maire, Benjamin Loubet, Polina Voylokov, Mark Sutton, and Ute Skiba
Biogeosciences, 16, 4731–4745, https://doi.org/10.5194/bg-16-4731-2019, https://doi.org/10.5194/bg-16-4731-2019, 2019
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Commonly used nitrogen fertilisers, ammonium nitrate, urea and urea coated with a urease inhibitor, were applied to experimental plots. Fertilisation with ammonium nitrate supported the largest yields but also resulted in the largest nitrous oxide emissions. Urea was the largest emitter of ammonia. The coated urea did not significantly increase yields; however, ammonia emissions were substantially smaller than urea. The coated urea was the best environmentally but is economically unattractive.
Boris Bonn, Ruth-Kristina Magh, Joseph Rombach, and Jürgen Kreuzwieser
Biogeosciences, 16, 4627–4645, https://doi.org/10.5194/bg-16-4627-2019, https://doi.org/10.5194/bg-16-4627-2019, 2019
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The effect of soil water availability (SWA) on emissions of isoprenoids by trees was studied by setting up a parameterization from published data. SWA impact on isoprene emissions can be described by a growth type curve, while monoterpene emissions display a pattern reflecting plants’ stomata opening. Sesquiterpene fluxes tend to increase at the start of severe drought until resources decline. Feedbacks on atmospheric processes such as ozone and aerosol particles are further studied.
Martin Jiskra, Jeroen E. Sonke, Yannick Agnan, Detlev Helmig, and Daniel Obrist
Biogeosciences, 16, 4051–4064, https://doi.org/10.5194/bg-16-4051-2019, https://doi.org/10.5194/bg-16-4051-2019, 2019
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The tundra plays a pivotal role in Arctic mercury cycling by storing atmospheric mercury deposition and shuttling it to the Arctic Ocean. We used the isotopic fingerprint of mercury to investigate the processes controlling atmospheric mercury deposition. We found that the uptake of atmospheric mercury by vegetation was the major deposition source. Direct deposition to snow or soils only played a minor role. These results improve our understanding of Arctic mercury cycling.
Paul C. Stoy, Tarek S. El-Madany, Joshua B. Fisher, Pierre Gentine, Tobias Gerken, Stephen P. Good, Anne Klosterhalfen, Shuguang Liu, Diego G. Miralles, Oscar Perez-Priego, Angela J. Rigden, Todd H. Skaggs, Georg Wohlfahrt, Ray G. Anderson, A. Miriam J. Coenders-Gerrits, Martin Jung, Wouter H. Maes, Ivan Mammarella, Matthias Mauder, Mirco Migliavacca, Jacob A. Nelson, Rafael Poyatos, Markus Reichstein, Russell L. Scott, and Sebastian Wolf
Biogeosciences, 16, 3747–3775, https://doi.org/10.5194/bg-16-3747-2019, https://doi.org/10.5194/bg-16-3747-2019, 2019
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Key findings are the nearly optimal response of T to atmospheric water vapor pressure deficits across methods and scales. Additionally, the notion that T / ET intermittently approaches 1, which is a basis for many partitioning methods, does not hold for certain methods and ecosystems. To better constrain estimates of E and T from combined ET measurements, we propose a combination of independent measurement techniques to better constrain E and T at the ecosystem scale.
Christian Stiegler, Ana Meijide, Yuanchao Fan, Ashehad Ashween Ali, Tania June, and Alexander Knohl
Biogeosciences, 16, 2873–2890, https://doi.org/10.5194/bg-16-2873-2019, https://doi.org/10.5194/bg-16-2873-2019, 2019
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We show the response of a commercial oil palm plantation in Indonesia to the extreme El Niño–Southern Oscillation (ENSO) event in 2015. Our measurements and model suggest that without human-induced forest fires and related smoke emissions, the observed negative impact on oil palm carbon dioxide greenhouse gas fluxes, carbon accumulation and yield due to ENSO-related drought would have been less pronounced. With respect to climate change we highlight the importance of fire prevention in the area.
Sven Boese, Martin Jung, Nuno Carvalhais, Adriaan J. Teuling, and Markus Reichstein
Biogeosciences, 16, 2557–2572, https://doi.org/10.5194/bg-16-2557-2019, https://doi.org/10.5194/bg-16-2557-2019, 2019
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This study examines how limited water availability during droughts affects water-use efficiency. This metric describes how much carbon an ecosystem can assimilate for each unit of water lost by transpiration. We test how well different water-use efficiency models can capture the dynamics of transpiration decrease due to increased soil-water limitation. Accounting for the interacting effects of radiation and water limitation is necessary to accurately predict transpiration during these periods.
Raia Silvia Massad, Juliette Lathière, Susanna Strada, Mathieu Perrin, Erwan Personne, Marc Stéfanon, Patrick Stella, Sophie Szopa, and Nathalie de Noblet-Ducoudré
Biogeosciences, 16, 2369–2408, https://doi.org/10.5194/bg-16-2369-2019, https://doi.org/10.5194/bg-16-2369-2019, 2019
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Human activities strongly interfere in the land–atmosphere interactions through changes in land use and land cover changes and land management. The objectives of this review are to synthesize the existing experimental and modelling works that investigate physical, chemical, and biogeochemical interactions between land surface and the atmosphere. Greater consideration of atmospheric chemistry, through land–atmosphere interactions, as a decision parameter for land management is essential.
Yuzo Miyazaki, Divyavani Gowda, Eri Tachibana, Yoshiyuki Takahashi, and Tsutom Hiura
Biogeosciences, 16, 2181–2188, https://doi.org/10.5194/bg-16-2181-2019, https://doi.org/10.5194/bg-16-2181-2019, 2019
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Fatty alcohols (FAs) are major components of surface lipids and can act as surface-active atmospheric organic aerosols, influencing the cloud formation. We identified five secondary FAs in atmospheric aerosols at two temperate forest sites and revealed their distinct seasonal variation for the first time. Our results suggest that they originated mostly from plant wax and could be used as useful tracers for primary biological aerosol particles.
Claire Delon, Corinne Galy-Lacaux, Dominique Serça, Erwan Personne, Eric Mougin, Marcellin Adon, Valérie Le Dantec, Benjamin Loubet, Rasmus Fensholt, and Torbern Tagesson
Biogeosciences, 16, 2049–2077, https://doi.org/10.5194/bg-16-2049-2019, https://doi.org/10.5194/bg-16-2049-2019, 2019
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In the Sahel region during the wet season, CO2 and NO are released to the atmosphere, and NH3 is deposited on the soil. During the dry season, processes are strongly reduced. This paper shows the temporal variation in these soil–atmosphere exchanges of trace gases for 2 years, their sharp increase when the first rains fall onto dry soils, and how microbial processes are involved. We use a modelling approach, which is necessary when continuous measurements are not possible in remote regions.
Anne Sofie Lansø, Thomas Luke Smallman, Jesper Heile Christensen, Mathew Williams, Kim Pilegaard, Lise-Lotte Sørensen, and Camilla Geels
Biogeosciences, 16, 1505–1524, https://doi.org/10.5194/bg-16-1505-2019, https://doi.org/10.5194/bg-16-1505-2019, 2019
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Although coastal regions only amount to 7 % of the global oceans, their contribution to the global oceanic surface exchange of CO2 is much greater. In this study, we gain detailed insight into how these coastal marine fluxes compare to CO2 exchange from coastal land regions. Annually, the coastal marine exchanges are smaller than the total uptake of CO2 from the land surfaces within the study area but comparable in size to terrestrial fluxes from individual land cover classes of the region.
Ravshan Eshonkulov, Arne Poyda, Joachim Ingwersen, Hans-Dieter Wizemann, Tobias K. D. Weber, Pascal Kremer, Petra Högy, Alim Pulatov, and Thilo Streck
Biogeosciences, 16, 521–540, https://doi.org/10.5194/bg-16-521-2019, https://doi.org/10.5194/bg-16-521-2019, 2019
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We compared the energy balance closure (EBC) under varying environmental conditions and investigated a wide range of possible reasons for the energy imbalance. As measures for the imbalance, we used ordinary linear regression, the energy balance ratio (EBR), and the energy residual. The EBR was also investigated as a function of buoyancy, friction velocity, and atmospheric stability. Moreover, the relationship between the EBC and flux source area or footprint was also investigated.
Juha-Pekka Tuovinen, Mika Aurela, Juha Hatakka, Aleksi Räsänen, Tarmo Virtanen, Juha Mikola, Viktor Ivakhov, Vladimir Kondratyev, and Tuomas Laurila
Biogeosciences, 16, 255–274, https://doi.org/10.5194/bg-16-255-2019, https://doi.org/10.5194/bg-16-255-2019, 2019
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We analysed ecosystem-scale measurements of methane exchange between Arctic tundra and the atmosphere, taking into account the large variations in vegetation and soil properties. The measurements are spatial averages, but using meteorological and statistical modelling techniques we could estimate methane emissions for different land cover types and quantify how well the measurements correspond to the spatial variability. This provides a more accurate estimate of the regional methane emission.
Cited articles
Abnizova, A., Siemens, J., Langer, M., and Boike, J.: Small ponds with major impact: The relevance of ponds and lakes in permafrost landscapes to carbon dioxide emissions, Global Biogeochem. Cy., 26, GB2041, https://doi.org/10.1029/2011gb004237, 2012.
Aubinet, M., Vesala, T., and Papale, D. (Eds.): Eddy Covariance - A Practical Guide to Measurement and Data Analysis, Series: Springer Atmospheric Sciences, Springer, Heidelberg, p. 438, 2012.
Aurela, M., Laurila, T., and Tuovinen, J. P.: The timing of snow melt controls the annual CO2 balance in a subarctic fen, Geophys. Res. Lett., 31, L16119, https://doi.org/10.1029/2004GL020315, 2004.
Björkman, M. P., Morgner, E., Björk, R. G., Cooper, E. J., Elberling, B., and Klemedtsson, L.: A comparison of annual and seasonal carbon dioxide effluxes between sub-Arctic Sweden and High-Arctic Svalbard, Polar Res., 29, 75–84, 2010a.
Björkman, M. P., Morgner, E., Cooper, E. J., Elberling, B., Klemedtsson, L., and Björk R. G.: Winter carbon dioxide effluxes from Arctic ecosystems: An overview and comparison of methodologies, Global Biogeochem. Cy., 24, GB3010, https://doi.org/10.1029/2009GB003667, 2010b.
Boike, J., Roth, K., and Ippisch, O.: Seasonal snow cover on frozen ground: Energy balance calculations of a permafrost site near Ny-Ålesund, Spitsbergen, J. Geophys. Res., 108, 8163, https://doi.org/10.1029/2001JD000939, 2003.
Boike, J., Ippisch, O., Overduin, P., Hagedorn, B., and Roth, K.: Water, heat and solute dynamics of a mud boil, Spitsbergen, Geomorphology, 95, 61–73, 2008.
Bowling D. R. and Massman, W. J.: Persistent wind-induced enhancement of diffusive CO2 transport in a mountain forest snowpack, J. Geophys. Res., 116, 1–15, https://doi.org/10.1029/2011JG001722, 2011.
Burba, G.: Eddy Covariance Method for Scientific, Industrial, Agricultural, and Regulatory Applications: A Field Book on Measuring Ecosystem Gas Exchange and Areal Emission Rates, LI-COR Biosciences Inc., Lincoln, NE, USA, 331 pp., 2013.
Burba, G. and Anderson, D.: A brief practical guide to eddy covariance flux measurements, Li-COR Biosciences Inc., Lincoln, NE, USA, 2010.
Burba, G., McDermitt, D. K., Grelle, A., Anderson, D., and Xu, L.: Addressing the influence of instrument surface heat exchange on the measurements of CO2 flux from open-path gas analyzers, Glob. Change Biol., 14, 1854–1876, 2008.
Chapin III, F. S., Miller, P. C., Billings, W. D., and Coyne, P. I.: Carbon and nutrient budgets and their control in coastal tundra, in: An arctic ecosystem: The coastal tundra at Barrow, Alaska, edited by: Brown, J., Miller, P. C., Tieszen, L. L., and Bunnell, F. L., Dowden, Hutchinson and Ross Inc., Stroudsburg/Pennsylvania, 458–482, 1980.
Corradi, C., Kolle, O., Walter, K., Zimov, S. A., and Schulze, E. D.: Carbon dioxide and methane exchange of a north-east Siberian tussock tundra, Glob. Change Biol., 11, 1910–1925, 2005.
Domine, F., Sparapani, R., Ianniello, A., and Beine, H. J.: The origin of sea salt in snow on Arctic sea ice and in coastal regions, Atmos. Chem. Phys., 4, 2259–2271, https://doi.org/10.5194/acp-4-2259-2004, 2004.
Eigenmann, R., Kalthoff, N., Foken, T., Dorninger, M., Kohler, M., Legain, D., Pigeon, G., Piguet, B., Schüttemeyer, D., and Traulle, O.: Surface energy balance and turbulence network during COPS, Q. J. Roy. Meteor. Soc., 137, 57–69, 2011.
Elberling, B. and Brandt, K. K.: Uncoupling of microbial CO2 production and CO2 release in frozen soil and its implications for field studies of arctic C cycling, Soil Biol. Biochem., 35, 263–272, 2003.
Euskirchen, E. S., Bret-Harte, M. S., Scott, G. J., Edgar, C., and Shaver, G. R.: Seasonal patterns of carbon dioxide and water fluxes in three representative tundra ecosystems in northern Alaska, Ecosphere, 3, 1–19, 2012.
Fahnestock, J. T., Jones, M. H., Brooks, P. D., Walker, D. A., and Welker, J. M.: Winter and spring CO2 Efflux from Tundra Communities of Northern Alaska, J. Geophys. Res., 103, 29023–29027, 1998.
Fahnestock, J. T., Jones, M. H., and Welker, J. M.: Wintertime CO2 efflux from arctic soils: implications for annual carbon budgets, Global Biogeochem. Cy., 13, 775–779, 1999.
Falge, E., Baldocchi, D., Olson, R., Anthoni, P., Aubinet, M., Bernhofer, C., Burba, G., Ceulemans, R., Clement, R., Dolman, H., Granier, A., Gross, P., Grunwald, T., Hollinger, D., Jensen, N. O., Katul, G., Keronen, P., Kowalski, A., Lai, C. T., Law, B. E., Meyers, T., Moncrieff, H., Moors, E., Munger, J. W., Pilegaard, K., Rannik, U., Rebmann, C., Suyker, A., Tenhunen, J., Tu, K., Verma, S., Vesala, T., Wilson, K., and Wofsy, S.: Gap filling strategies for defensible annual sums of net ecosystem exchange, Agr. Forest Meteorol., 107, 43–69, 2001.
Finnigan, J., Clement, R., Malhi, Y., Leuning, R., and Cleugh, H. A.: A reevaluation of long-term flux measurement techniques. Part I: Averaging and coordinate rotation, Bound-Lay Meteorol., 107, 1–48, 2003.
Foken, T.: Micrometeorology, Springer, Heidelberg, 2008.
Foken, T. and Wichura, B.: Tools for quality assessment of surface-based flux measurements, Agr. Forest Meteorol., 78, 83–105, 1996.
Foken, T., Göckede, M., Mauder, M., Mahrt, L., Amiro, B. D., and Munger, J. W.: Post-field data quality control, in: Handbook of Micrometeorology: A Guide for Surface Flux Measurement and Analysis, edited by: Lee, X., Massman, W., Law, B. E., Kluwer, Dordrecht, 181–208, 2004.
Foken, T., Leuning, R., Oncley, S. P., Mauder, M., and Aubinet, M.: Corrections and data quality, in: Eddy Covariance: A Practical Guide to Measurement and Data Analysis, edited by: Aubinet, M., Vesala, T., and Papale, D., Springer, Berlin, Heidelberg, 85–131, 2012.
Graven, H., Keeling, R., Piper, S., Patra, P., Stephens, B., Wofsy, S., Welp, L., Sweeney, C., Tans, P., Kelley, J., Daube, B. C., Kort, E. A., Santoni, G. W., and Bent, J. D.: Enhanced seasonal exchange of CO2 by northern ecosystems since 1960, Science, 341, 1085–1089, 2013.
Grelle, A. and Burba, G.: Fine-wire thermometer to correct CO2 fluxes by open-path analyzers for artificial density fluctuations, Agr. Forest Meteorol., 147, 48–57, 2007.
Groendahl, L., Friborg, T., and Soegaard, H.: Temperature and snow-melt controls on interannual variability in carbon exchange in the high Arctic, Theor. Appl. Climatol., 88, 111–125, 2007.
Grogan, P. and Chapin III, F. S.: Arctic soil respiration: Effects of climate and vegetation depend on season, Ecosystems, 2, 451–459, 1999.
Hanssen-Bauer, I. and Førland, E. J.: Long-term trends in precipitation and temperature in the Norwegian Arctic: can they be explained by changes in atmospheric circulation patterns?, Clim. Res., 10, 143–153, 1998.
Heikkinen, J. E. P., Virtanen, T., Huttunen, J. T., Elsakov, V., and Martikainen, P. J.: Carbon balance in East European tundra, Global Biogeochem. Cy., 18, GB1023, https://doi.org/10.1029/2003GB002054, 2004.
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