Articles | Volume 14, issue 11
https://doi.org/10.5194/amt-14-7291-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-14-7291-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Importance of the Webb, Pearman, and Leuning (WPL) correction for the measurement of small CO2 fluxes
Katharina Jentzsch
Alfred Wegener Institute, Telegrafenberg A6, 14473 Potsdam, Germany
Julia Boike
Alfred Wegener Institute, Telegrafenberg A6, 14473 Potsdam, Germany
Geography Department, Humboldt-Universität zu Berlin, 12489
Berlin, Germany
Thomas Foken
CORRESPONDING AUTHOR
University of Bayreuth, Bayreuth Center of Ecology and
Environmental Research (BayCEER), 95440 Bayreuth, Germany
Related authors
Katharina Jentzsch, Lona van Delden, Matthias Fuchs, and Claire C. Treat
Earth Syst. Sci. Data, 17, 2331–2372, https://doi.org/10.5194/essd-17-2331-2025, https://doi.org/10.5194/essd-17-2331-2025, 2025
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Methane is a greenhouse gas that contributes to global warming, but we do not fully understand how much is released from natural sources like wetlands. To measure methane over large areas, many measurements are needed, often from small chambers that are placed on the ground. However, different researchers use different measurement setups, making it hard to combine data. We surveyed 36 researchers about their methods, summarized the responses, and identified ways to make the data more comparable.
Katharina Jentzsch, Elisa Männistö, Maija E. Marushchak, Aino Korrensalo, Lona van Delden, Eeva-Stiina Tuittila, Christian Knoblauch, and Claire C. Treat
Biogeosciences, 21, 3761–3788, https://doi.org/10.5194/bg-21-3761-2024, https://doi.org/10.5194/bg-21-3761-2024, 2024
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During cold seasons, methane release from northern wetlands is important but often underestimated. We studied a boreal bog to understand methane emissions in spring and fall. At cold temperatures, methane release decreases due to lower production rates, but efficient methane transport through plant structures, decaying plants, and the release of methane stored in the pore water keep emissions ongoing. Understanding these seasonal processes can improve models for methane release in cold climates.
Mehriban Aliyeva, Michael Angelopoulos, Julia Boike, Moritz Langer, Frederieke Miesner, Scott Dallimore, Dustin Whalen, Lukas U. Arenson, and Pier Paul Overduin
EGUsphere, https://doi.org/10.5194/egusphere-2025-2675, https://doi.org/10.5194/egusphere-2025-2675, 2025
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In this study, we investigate the ongoing transformation of terrestrial permafrost into subsea permafrost on a rapidly eroding Arctic island using electrical resistivity tomography and numerical modelling. We draw on 60 years of shoreline data to support our findings. This work is important for understanding permafrost loss in Arctic coastal areas and for guiding future efforts to protect vulnerable shorelines.
Katharina Jentzsch, Lona van Delden, Matthias Fuchs, and Claire C. Treat
Earth Syst. Sci. Data, 17, 2331–2372, https://doi.org/10.5194/essd-17-2331-2025, https://doi.org/10.5194/essd-17-2331-2025, 2025
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Methane is a greenhouse gas that contributes to global warming, but we do not fully understand how much is released from natural sources like wetlands. To measure methane over large areas, many measurements are needed, often from small chambers that are placed on the ground. However, different researchers use different measurement setups, making it hard to combine data. We surveyed 36 researchers about their methods, summarized the responses, and identified ways to make the data more comparable.
Ephraim Erkens, Michael Angelopoulos, Jens Tronicke, Scott R. Dallimore, Dustin Whalen, Julia Boike, and Pier Paul Overduin
The Cryosphere, 19, 997–1012, https://doi.org/10.5194/tc-19-997-2025, https://doi.org/10.5194/tc-19-997-2025, 2025
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We investigate the depth of subsea permafrost formed by inundation of terrestrial permafrost due to marine transgression around the rapidly disappearing, permafrost-cored Tuktoyaktuk Island (Beaufort Sea, NWT, Canada). We use geoelectrical surveys with floating electrodes to identify the boundary between unfrozen and frozen sediment. Our findings indicate that permafrost thaw depths beneath the seabed can be explained by coastal erosion rates and landscape features before inundation.
Tabea Rettelbach, Ingmar Nitze, Inge Grünberg, Jennika Hammar, Simon Schäffler, Daniel Hein, Matthias Gessner, Tilman Bucher, Jörg Brauchle, Jörg Hartmann, Torsten Sachs, Julia Boike, and Guido Grosse
Earth Syst. Sci. Data, 16, 5767–5798, https://doi.org/10.5194/essd-16-5767-2024, https://doi.org/10.5194/essd-16-5767-2024, 2024
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Permafrost landscapes in the Arctic are rapidly changing due to climate warming. Here, we publish aerial images and elevation models with very high spatial detail that help study these landscapes in northwestern Canada and Alaska. The images were collected using the Modular Aerial Camera System (MACS). This dataset has significant implications for understanding permafrost landscape dynamics in response to climate change. It is publicly available for further research.
Katharina Jentzsch, Elisa Männistö, Maija E. Marushchak, Aino Korrensalo, Lona van Delden, Eeva-Stiina Tuittila, Christian Knoblauch, and Claire C. Treat
Biogeosciences, 21, 3761–3788, https://doi.org/10.5194/bg-21-3761-2024, https://doi.org/10.5194/bg-21-3761-2024, 2024
Short summary
Short summary
During cold seasons, methane release from northern wetlands is important but often underestimated. We studied a boreal bog to understand methane emissions in spring and fall. At cold temperatures, methane release decreases due to lower production rates, but efficient methane transport through plant structures, decaying plants, and the release of methane stored in the pore water keep emissions ongoing. Understanding these seasonal processes can improve models for methane release in cold climates.
Soraya Kaiser, Julia Boike, Guido Grosse, and Moritz Langer
Earth Syst. Sci. Data, 16, 3719–3753, https://doi.org/10.5194/essd-16-3719-2024, https://doi.org/10.5194/essd-16-3719-2024, 2024
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Arctic warming, leading to permafrost degradation, poses primary threats to infrastructure and secondary ecological hazards from possible infrastructure failure. Our study created a comprehensive Alaska inventory combining various data sources with which we improved infrastructure classification and data on contaminated sites. This resource is presented as a GeoPackage allowing planning of infrastructure damage and possible implications for Arctic communities facing permafrost challenges.
Frederieke Miesner, William Lambert Cable, Pier Paul Overduin, and Julia Boike
The Cryosphere, 18, 2603–2611, https://doi.org/10.5194/tc-18-2603-2024, https://doi.org/10.5194/tc-18-2603-2024, 2024
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The temperature in the sediment below Arctic lakes determines the stability of the permafrost and microbial activity. However, measurements are scarce because of the remoteness. We present a robust and portable device to fill this gap. Test campaigns have demonstrated its utility in a range of environments during winter and summer. The measured temperatures show a great variability within and across locations. The data can be used to validate models and estimate potential emissions.
Victoria R. Dutch, Nick Rutter, Leanne Wake, Oliver Sonnentag, Gabriel Hould Gosselin, Melody Sandells, Chris Derksen, Branden Walker, Gesa Meyer, Richard Essery, Richard Kelly, Phillip Marsh, Julia Boike, and Matteo Detto
Biogeosciences, 21, 825–841, https://doi.org/10.5194/bg-21-825-2024, https://doi.org/10.5194/bg-21-825-2024, 2024
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We undertake a sensitivity study of three different parameters on the simulation of net ecosystem exchange (NEE) during the snow-covered non-growing season at an Arctic tundra site. Simulations are compared to eddy covariance measurements, with near-zero NEE simulated despite observed CO2 release. We then consider how to parameterise the model better in Arctic tundra environments on both sub-seasonal timescales and cumulatively throughout the snow-covered non-growing season.
Jennika Hammar, Inge Grünberg, Steven V. Kokelj, Jurjen van der Sluijs, and Julia Boike
The Cryosphere, 17, 5357–5372, https://doi.org/10.5194/tc-17-5357-2023, https://doi.org/10.5194/tc-17-5357-2023, 2023
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Roads on permafrost have significant environmental effects. This study assessed the Inuvik to Tuktoyaktuk Highway (ITH) in Canada and its impact on snow accumulation, albedo and snowmelt timing. Our findings revealed that snow accumulation increased by up to 36 m from the road, 12-day earlier snowmelt within 100 m due to reduced albedo, and altered snowmelt patterns in seemingly undisturbed areas. Remote sensing aids in understanding road impacts on permafrost.
Juditha Aga, Julia Boike, Moritz Langer, Thomas Ingeman-Nielsen, and Sebastian Westermann
The Cryosphere, 17, 4179–4206, https://doi.org/10.5194/tc-17-4179-2023, https://doi.org/10.5194/tc-17-4179-2023, 2023
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This study presents a new model scheme for simulating ice segregation and thaw consolidation in permafrost environments, depending on ground properties and climatic forcing. It is embedded in the CryoGrid community model, a land surface model for the terrestrial cryosphere. We describe the model physics and functionalities, followed by a model validation and a sensitivity study of controlling factors.
Brian Groenke, Moritz Langer, Jan Nitzbon, Sebastian Westermann, Guillermo Gallego, and Julia Boike
The Cryosphere, 17, 3505–3533, https://doi.org/10.5194/tc-17-3505-2023, https://doi.org/10.5194/tc-17-3505-2023, 2023
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It is now well known from long-term temperature measurements that Arctic permafrost, i.e., ground that remains continuously frozen for at least 2 years, is warming in response to climate change. Temperature, however, only tells half of the story. In this study, we use computer modeling to better understand how the thawing and freezing of water in the ground affects the way permafrost responds to climate change and what temperature trends can and cannot tell us about how permafrost is changing.
Sebastian Westermann, Thomas Ingeman-Nielsen, Johanna Scheer, Kristoffer Aalstad, Juditha Aga, Nitin Chaudhary, Bernd Etzelmüller, Simon Filhol, Andreas Kääb, Cas Renette, Louise Steffensen Schmidt, Thomas Vikhamar Schuler, Robin B. Zweigel, Léo Martin, Sarah Morard, Matan Ben-Asher, Michael Angelopoulos, Julia Boike, Brian Groenke, Frederieke Miesner, Jan Nitzbon, Paul Overduin, Simone M. Stuenzi, and Moritz Langer
Geosci. Model Dev., 16, 2607–2647, https://doi.org/10.5194/gmd-16-2607-2023, https://doi.org/10.5194/gmd-16-2607-2023, 2023
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The CryoGrid community model is a new tool for simulating ground temperatures and the water and ice balance in cold regions. It is a modular design, which makes it possible to test different schemes to simulate, for example, permafrost ground in an efficient way. The model contains tools to simulate frozen and unfrozen ground, snow, glaciers, and other massive ice bodies, as well as water bodies.
Victoria R. Dutch, Nick Rutter, Leanne Wake, Melody Sandells, Chris Derksen, Branden Walker, Gabriel Hould Gosselin, Oliver Sonnentag, Richard Essery, Richard Kelly, Phillip Marsh, Joshua King, and Julia Boike
The Cryosphere, 16, 4201–4222, https://doi.org/10.5194/tc-16-4201-2022, https://doi.org/10.5194/tc-16-4201-2022, 2022
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Measurements of the properties of the snow and soil were compared to simulations of the Community Land Model to see how well the model represents snow insulation. Simulations underestimated snow thermal conductivity and wintertime soil temperatures. We test two approaches to reduce the transfer of heat through the snowpack and bring simulated soil temperatures closer to measurements, with an alternative parameterisation of snow thermal conductivity being more appropriate.
Jan Nitzbon, Damir Gadylyaev, Steffen Schlüter, John Maximilian Köhne, Guido Grosse, and Julia Boike
The Cryosphere, 16, 3507–3515, https://doi.org/10.5194/tc-16-3507-2022, https://doi.org/10.5194/tc-16-3507-2022, 2022
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The microstructure of permafrost soils contains clues to its formation and its preconditioning to future change. We used X-ray computed tomography (CT) to measure the composition of a permafrost drill core from Siberia. By combining CT with laboratory measurements, we determined the the proportions of pore ice, excess ice, minerals, organic matter, and gas contained in the core at an unprecedented resolution. Our work demonstrates the potential of CT to study permafrost properties and processes.
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, https://doi.org/10.5194/bg-19-3863-2022, https://doi.org/10.5194/bg-19-3863-2022, 2022
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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.
Noah D. Smith, Eleanor J. Burke, Kjetil Schanke Aas, Inge H. J. Althuizen, Julia Boike, Casper Tai Christiansen, Bernd Etzelmüller, Thomas Friborg, Hanna Lee, Heather Rumbold, Rachael H. Turton, Sebastian Westermann, and Sarah E. Chadburn
Geosci. Model Dev., 15, 3603–3639, https://doi.org/10.5194/gmd-15-3603-2022, https://doi.org/10.5194/gmd-15-3603-2022, 2022
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The Arctic has large areas of small mounds that are 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, and thus the soil absorbs more heat in summer. The warm wet soil in the hollows decomposes, releasing methane. We have made a model of this, and we have tested how it behaves and whether it looks like sites in Scandinavia and Siberia. Sometimes we get more methane than a model without mounds.
Bruna R. F. Oliveira, Jan J. Keizer, and Thomas Foken
Biogeosciences, 19, 2235–2243, https://doi.org/10.5194/bg-19-2235-2022, https://doi.org/10.5194/bg-19-2235-2022, 2022
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This study analyzes the impacts of this windthrow on the aerodynamic characteristics of zero-plane displacement and roughness length and, ultimately, their implications for the turbulent fluxes. The turbulent fluxes were only affected to a minor degree by the windthrow, but the footprint area of the flux tower changed markedly so that the target area of the measurements had to be redetermined.
Stefan Kruse, Simone M. Stuenzi, Julia Boike, Moritz Langer, Josias Gloy, and Ulrike Herzschuh
Geosci. Model Dev., 15, 2395–2422, https://doi.org/10.5194/gmd-15-2395-2022, https://doi.org/10.5194/gmd-15-2395-2022, 2022
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We coupled established models for boreal forest (LAVESI) and permafrost dynamics (CryoGrid) in Siberia to investigate interactions of the diverse vegetation layer with permafrost soils. Our tests showed improved active layer depth estimations and newly included species growth 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.
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.
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.
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.
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.
Bruna R. F. Oliveira, Carsten Schaller, J. Jacob Keizer, and Thomas Foken
Biogeosciences, 18, 285–302, https://doi.org/10.5194/bg-18-285-2021, https://doi.org/10.5194/bg-18-285-2021, 2021
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Forest fires have a significant impact on carbon dioxide emissions. The present study from a pine forest in Portugal is one of the few where measurements of CO2 fluxes were started immediately (1.5 months) after the forest fire. Carbon dioxide emissions were linked to soil humidity. Therefore, they started after the beginning of the rainfall in autumn. Due to the beginning of vegetation, the site was already a carbon dioxide sink the following year.
Cited articles
Aubinet, M., Vesala, T., and Papale, D. (Eds.): Eddy covariance: A Practical Guide to Measurement and Data Analysis, Springer, Dordrecht, Heidelberg, London, New York, 438 pp., https://doi.org/10.1007/978-94-007-2351-1, 2012.
Boike, J.: FLUXNET database, available at: http://www.europe-fluxdata.eu/;ID:Sj-Blv, last access: 17 November 2021.
Burba, G., McDermitt, D. K., Grelle, A., Anderson, D. J., 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, https://doi.org/10.1111/j.1365-2486.2008.01606.x, 2008.
Burba, G., Anderson, T., and Komissarov, A.: Accounting for spectroscopic
effects in laser-based open-path eddy covariance flux measurements, Glob.
Change Biol., 2019, 14614, https://doi.org/10.1111/gcb.14614, 2019.
Foken, T.: Anmerkungen zur Problematik möglicher Fehler bei der
Bestimmung turbulenter Austauschströme nach der Flux-Methode (Remarks on
the problem of possible errors in the determination of turbulent exchange
according to the flux method), Z. Meteorol., 39, 112–113, 1989.
Foken, T.: Micrometeorology, 2nd Edn., Springer, Berlin, Heidelberg, 362
pp., https://doi.org/10.1007/978-3-642-25440-6, 2017.
Foken, T. and Wichura, B.: Tools for quality assessment of surface-based
flux measurements, Agr. Forest Meteorol., 78, 83–105, https://doi.org/10.1016/0168-1923(95)02248-1, 1996.
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, Dordrecht, Heidelberg, London, New York, 85–131, https://doi.org/10.1007/978-94-007-2351-1_4, 2012.
Foken, T., Hellmuth, O., Huwe, B., and Sonntag, D.: Physical quantities, in: Springer
Handbook of Atmospheric Measurements, edited by: Foken, T., Springer Nature,
Switzerland, 107–151, https://doi.org/10.1007/978-3-030-51171-4_5, 2021.
Hesselberg, T.: Die Gesetze der ausgeglichenen atmosphärischen
Bewegungen, Beiträge zur Physik der freien Atmosphäre, 12, 141–160, 1926.
Jentzsch, K., Schulz, A., Pirk, N., Foken, T., Crewell, S., and Boike, J.:
High levels of CO2 exchange during synoptic-scale events introduce large
uncertainty into the Arctic carbon budget, Geophys. Res. Lett., 48,
e2020GL092256, https://doi.org/10.1029/2020GL092256, 2021.
Kittler, F., Eugster, W., Foken, T., Heimann, M., Kolle, O., and
Göckede, M.: High-quality eddy-covariance CO2 budgets under cold
climate conditions, J. Geophys. Res.-Biogeo., 122, 2064–2084, https://doi.org/10.1002/2017JG003830, 2017.
Kondo, F., Ono, K., Mano, M., Miyata, A., and Tsukamoto, O.: Experimental
evaluation of water vapour cross-sensitivity for accurate eddy covariance
measurement of CO2 flux using open-path CO2/H2O gas
analysers, Tellus B, 66, 23803, https://doi.org/10.3402/tellusb.v66.23803, 2014.
Kowalski, A. S. and Serrano-Ortiz, P.: On the relationship between the eddy
covariance, the turbulent flux, and surface exchange for a trace gas such as
CO2, Bound.-Lay. Meteorol., 124, 129–141, https://doi.org/10.1007/s10546-007-9171-z, 2007.
Kramm, G., Dlugi, R., and Lenschow, D. H.: A re-evaluation of the Webb
correction using density weighted averages, J. Hydrol., 166, 293–311, https://doi.org/10.1016/0022-1694(94)05088-F, 1995.
Leuning, R.: Measurements of trace gas fluxes in the atmosphere using eddy
covariance: WPL corrections revisited, in: Handbook of Micrometeorology: A
Guide for Surface Flux Measurements and Analysis, edited by: Lee, X.,
Massman, W. J., and Law, B., Kluwer, Dordrecht, 119–132, https://doi.org/10.1007/1-4020-2265-4_6, 2004.
Leuning, R.: The correct form of the Webb, Pearman and Leuning equation for
eddy fluxes of trace gases in steady and non-steady state, horizontally
homogeneous flows, Bound.-Lay. Meteorol., 123, 263–267, https://doi.org/10.1007/s10546-006-9138-5, 2007.
Liebethal, C. and Foken, T.: On the significance of the Webb correction to
fluxes, Bound.-Lay. Meteorol., 109, 99–106, https://doi.org/10.1023/A:1025421903542,
2003.
Liebethal, C. and Foken, T.: On the significance of the Webb correction to
fluxes, Corrigendum, Bound.-Lay. Meteorol., 113, 301, https://doi.org/10.1023/B:BOUN.0000039451.75031.ce, 2004.
Lloyd, J. and Taylor, J. A.: On the temperature dependence of soil
respiration, Funct. Ecol., 8, 315–323, https://doi.org/10.2307/2389824, 1994.
Lüers, J., Westermann, S., Piel, K., and Boike, J.: Annual CO2 budget and seasonal CO2 exchange signals at a high Arctic permafrost site on Spitsbergen, Svalbard archipelago, Biogeosciences, 11, 6307–6322, https://doi.org/10.5194/bg-11-6307-2014, 2014.
Mauder, M., Cuntz, M., Drüe, C., Graf, A., Rebmann, C., Schmid, H. P.,
Schmidt, M., and Steinbrecher, R.: A strategy for quality and uncertainty
assessment of long-term eddy-covariance measurements, Agr. Forest Meteorol.,
169, 122–135, https://doi.org/10.1016/j.agrformet.2012.09.006, 2013.
Mauder, M., Foken, T., Aubinet, M., and Ibrom, A.: Eddy-Covariance
Measurements, in: Springer Handbook of Atmospheric Measurements, edited by:
Foken, T., Springer Nature, Switzerland, 1473–1504, https://doi.org/10.1007/978-3-030-51171-4_55, 2021.
Oliveira, B. R. F., Schaller, C., Keizer, J. J., and Foken, T.: Estimating immediate post-fire carbon fluxes using the eddy-covariance technique, Biogeosciences, 18, 285–302, https://doi.org/10.5194/bg-18-285-2021, 2021.
Papale, D., Reichstein, M., Aubinet, M., Canfora, E., Bernhofer, C., Kutsch, W., Longdoz, B., Rambal, S., Valentini, R., Vesala, T., and Yakir, D.: Towards a standardized processing of Net Ecosystem Exchange measured with eddy covariance technique: algorithms and uncertainty estimation, Biogeosciences, 3, 571–583, https://doi.org/10.5194/bg-3-571-2006, 2006.
Stull, R. B.: An Introduction to Boundary Layer Meteorology, Kluwer,
Dordrecht, 666 pp., https://doi.org/10.1007/978-94-009-3027-8, 1988.
Su, Y. G., Wu, L., Zhou, Z. B., Liu, Y. B., and Zhang, Y. M.: Carbon flux in
deserts depends on soil cover type: A case study in the Gurbantunggute
desert, North China, Soil Biol. Biochem., 58, 332–340, doi:https://doi.org/10.1016/j.soilbio.2012.12.006, 2013.
Webb, E. K., Pearman, G. I., and Leuning, R.: Correction of the flux
measurements for density effects due to heat and water vapour transfer,
Q. J. Roy. Meteor. Soc., 106, 85–100, https://doi.org/10.1002/qj.49710644707,
1980.
Westermann, S., Lüers, J., Langer, M., Piel, K., and Boike, J.: The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway, The Cryosphere, 3, 245–263, https://doi.org/10.5194/tc-3-245-2009, 2009.
Short summary
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.
Very small CO2 fluxes are measured at night in Arctic regions. If the sensible heat flux is not...