Article
Energy & Fuels
Zhen Li, Erik Spangenberg, Judith M. Schicks, Thomas Kempka
Summary: The Mackenzie Delta is a permafrost-bearing region in the Canadian Arctic with high sub-permafrost gas hydrate reserves. The gas hydrates in the region are dominated by thermogenic methane migrated from deep hydrocarbon reservoirs. A numerical model simulation validates the hypothesis that dissolved methane from deeper reservoirs forms the gas hydrate accumulations in the delta. The simulation also reveals the impact of global temperature increase and Arctic Amplification effect on permafrost temperatures.
Article
Environmental Sciences
Mark J. Lara, Yaping Chen, Benjamin M. Jones
Summary: The study analyzed the drivers of gradual and catastrophic lake drainage in northern Alaska over 45 years using Landsat observations. Results showed that drivers of gradual drainage were mainly related to lake morphology and temperature, while catastrophic drainage was associated with thawing season length and precipitation.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Green & Sustainable Science & Technology
Lin Chen, Yuanming Lai, Daniel Fortier, Stuart A. Harris
Summary: This study investigates the impacts of snow cover on the air circulation pattern and finds that snow greatly weakens the cooling effect of closed embankment slopes. On the other hand, a U-shape closed embankment performs better in cooling due to stronger air convection in winter. The results suggest that a U-shape embankment can be a potential long-term solution to mitigate permafrost thaw.
Article
Environmental Sciences
Jason A. Clark, Ken D. Tape, Latha Baskaran, Clayton Elder, Charles Miller, Kimberley Miner, Jonathan A. O'Donnell, Benjamin M. Jones
Summary: Beaver engineering in the Arctic tundra leads to hydrologic and geomorphic changes that promote methane production. This methane emission is caused by factors such as vegetation inundation, conversion from flowing to stagnant systems, accumulation of organic sediments, elevated water tables, anaerobic conditions, and permafrost thawing. A study using hyperspectral remote sensing data found that methane hotspots were concentrated within 30 meters of water bodies, and there was a significantly higher occurrence of methane hotspots around beaver ponds compared to non-beaver water bodies. This highlights the impact of beaver-mediated methane emissions on the Arctic carbon cycle and the effects of climate change.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
Julia Steinbach, Henry Holmstrand, Kseniia Shcherbakova, Denis Kosmach, Volker Bruchert, Natalia Shakhova, Anatoly Salyuk, Celia J. Sapart, Denis Chernykh, Riko Noormets, Igor Semiletov, Orjan Gustafsson
Summary: The study investigates the sources of methane release in the East Siberian Arctic Shelf, indicating a significant contribution from submerged carbon and methane. Methane concentrations in the Laptev Sea showed large fluctuations and isotopic composition suggested a thermogenic/natural gas source in two seepage areas, with methane oxidation occurring further from the seeps. This knowledge is crucial for predicting future methane emissions in the region.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Meteorology & Atmospheric Sciences
Lori Bruhwiler, Frans-Jan W. Parmentier, Patrick Crill, Mark Leonard, Paul Palmer
Summary: The Arctic has experienced rapid climate change, driving changes in the carbon budget through vegetation, soil, fires, and wetlands; Observations suggest a more active CO2 cycle in high northern latitude ecosystems, with increased uptake by boreal forests and Arctic ecosystems; However, there is currently no strong evidence of increased CH4 emissions.
CURRENT CLIMATE CHANGE REPORTS
(2021)
Article
Environmental Sciences
Li Zhi-Long, Mu Cui-Cui, Chen Xu, Wang Xing-Yu, Dong Wen-Wen, Jia Lin, Mu Mei, Irina Streletskaya, Valery Grebenets, Sergey Sokratov, Alexander Kizyakov, Wu Xiao-Dong
Summary: The study revealed the annual net ecosystem carbon exchange (NEE) in the Arctic regions from 2002 to 2017, showing that forest, shrub, grassland, wetland, and tundra have varying levels of CO2 exchange. Grassland emissions decreased, while shrub and forest assimilation increased, and wetland and tundra shifted from carbon sources to sinks. Seasonal variations in NEE temperature sensitivities(Q(10)) were observed, with higher values in winter and lower values in summer, suggesting that the Arctic terrestrial ecosystem acts as a carbon sink currently, but future warming could potentially reduce this carbon sink capacity.
ADVANCES IN CLIMATE CHANGE RESEARCH
(2021)
Article
Multidisciplinary Sciences
Ken D. Tape, Jason A. Clark, Benjamin M. Jones, Seth Kantner, Benjamin Gaglioti, Guido Grosse, Ingmar Nitze
Summary: Recent findings show that beavers have moved into the Arctic tundra and are controlling surface water dynamics through the construction of beaver ponds. The rapid expansion of beaver engineering is important for understanding permafrost thawing and the exacerbation of climate change effects.
SCIENTIFIC REPORTS
(2022)
Article
Environmental Sciences
Dmitry A. Streletskiy, Sonia Clemens, Jean-Pierre Lanckman, Nikolay Shiklomanov
Summary: Climate change has negative impacts on Arctic ecosystems and northern communities, including disruptions in subsistence practices and threats to infrastructure. This study examines the effects of permafrost degradation on infrastructure in the Arctic region. Using climate models, the researchers estimate the changes in permafrost bearing capacity and ground subsidence, and identify infrastructure at risk. The results show significant costs associated with permafrost degradation, particularly in Russia. However, reducing greenhouse gas emissions can help mitigate these damages and inform adaptation strategies in Arctic states.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Geography, Physical
Taylor D. Sullivan, Andrew D. Parsekian, Janelle Sharp, Philip J. Hanke, Frederic Thalasso, Mark Shapley, Melanie Engram, Katey Walter Anthony
Summary: The occurrence and magnitude of natural fossil methane emissions in the Arctic are poorly known, with particular interest in geologic CH4 emissions due to the potential for positive feedback to climate warming. In Esieh Lake, geologic CH4 is being vented through pockmarks on the lake bottom, making it one of the highest flux geologic CH4 seep fields known on land. The poleward retreat of continuous permafrost may lead to more subcap methane release with increased permafrost thaw.
PERMAFROST AND PERIGLACIAL PROCESSES
(2021)
Article
Biodiversity Conservation
Donatella Zona, Peter M. Lafleur, Koen Hufkens, Beniamino Gioli, Barbara Bailey, George Burba, Eugenie S. Euskirchen, Jennifer D. Watts, Kyle A. Arndt, Mary Farina, John S. Kimball, Martin Heimann, Mathias Gockede, Martijn Pallandt, Torben R. Christensen, Mikhail Mastepanov, Efren Lopez-Blanco, Albertus J. Dolman, Roisin Commane, Charles E. Miller, Josh Hashemi, Lars Kutzbach, David Holl, Julia Boike, Christian Wille, Torsten Sachs, Aram Kalhori, Elyn R. Humphreys, Oliver Sonnentag, Gesa Meyer, Gabriel H. Gosselin, Philip Marsh, Walter C. Oechel
Summary: Long-term records of atmospheric CO2 concentration indicate a decrease in the positive effect of warming on carbon uptake in high-latitude regions since the 1990s. This study used data from permafrost tundra sites across the circumpolar Arctic to examine the temperature responses of ecosystem carbon fluxes and their relationship with soil moisture. The results suggest that reduced soil moisture during peak summer may limit plant productivity and carbon sequestration in tundra ecosystems.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Engineering, Environmental
Oleg Anisimov, Sergei Zimov
Summary: The study indicates that methane emission in Siberian permafrost regions will increase by less than 20 Tg/year by the mid-21st century, leading to a global temperature rise of less than 0.02 degrees Celsius. This challenges the methane bomb concept and suggests that the feedback between thawing Siberian wetlands and the global climate has been overestimated.
Article
Geography, Physical
Jeffrey M. McKenzie, Barret L. Kurylyk, Michelle A. Walvoord, Victor F. Bense, Daniel Fortier, Christopher Spence, Christophe Grenier
Summary: As permafrost thaws in the Arctic, new subsurface pathways open for the transport of groundwater, energy, and solutes, leading to increased contaminant transport, modification to water resources, and infrastructure damage. Groundwater is a catalyst of change in Arctic regions and cryohydrogeology should be more prominently included in research initiatives to understand these environmental and societal changes.
Article
Geosciences, Multidisciplinary
Rebecca Rolph, Pier Paul Overduin, Thomas Ravens, Hugues Lantuit, Moritz Langer
Summary: Studies have shown that climate change is intensifying Arctic coastal erosion, necessitating numerical models to understand its impact. ArcticBeach v1.0 is a potential starting point for Arctic erosion modeling that can be applied on different types of Arctic coastlines.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Nitin Chaudhary, Wenxin Zhang, Shubhangi Lamba, Sebastian Westermann
Summary: In this study, the peatland-vegetation model (LPJ-GUESS) was used to simulate peatland carbon dynamics under different future climate conditions. It was found that under less pronounced warming, peatlands may enhance their carbon sink capacity and buffer the effects of climate change. However, in a warmer world, higher respiration rates will dominate the carbon dynamics and reduce the carbon sink capacity.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Matthew A. Thomas, Alejandro Mota, Benjamin M. Jones, R. Charles Choens, Jennifer M. Frederick, Diana L. Bull
FRONTIERS IN EARTH SCIENCE
(2020)
Article
Geosciences, Multidisciplinary
Rodrigo Chi-Duran, Margaret S. Avery, Nicholas Knezek, Bruce A. Buffett
GEOPHYSICAL RESEARCH LETTERS
(2020)
Article
Environmental Sciences
Sayedeh Sara Sayedi, Benjamin W. Abbott, Brett F. Thornton, Jennifer M. Frederick, Jorien E. Vonk, Paul Overduin, Christina Schadel, Edward A. G. Schuur, Annie Bourbonnais, Nikita Demidov, Anatoly Gavrilov, Shengping He, Gustaf Hugelius, Martin Jakobsson, Miriam C. Jones, DongJoo Joung, Gleb Kraev, Robie W. Macdonald, A. David McGuire, Cuicui Mu, Matt O'Regan, Kathryn M. Schreiner, Christian Stranne, Elena Pizhankova, Alexander Vasiliev, Sebastian Westermann, Jay P. Zarnetske, Tingjun Zhang, Mehran Ghandehari, Sarah Baeumler, Brian C. Brown, Rebecca J. Frei
ENVIRONMENTAL RESEARCH LETTERS
(2020)
Article
Geochemistry & Geophysics
B. A. Buffett
Summary: In this study, 3-D numerical calculations were used to assess the transition to turbulence in precessional flow, indicating that the transition to turbulence occurs near Re=500, higher than the typical value for stable Ekman layers. Complications due to fluid stratification or a magnetic field may suppress the transition to turbulence, reducing the likelihood of turbulent Ekman layers in the Earth's core.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Geochemistry & Geophysics
William K. Eymold, Jennifer M. Frederick, Michael Nole, Benjamin J. Phrampus, Warren T. Wood
Summary: Methane hydrates are solid structures containing methane that form under low temperature and high pressure conditions. This study developed a workflow to predict methane hydrate occurrence using statistical and machine learning methods. Results suggest that elevated hydrate formation is associated with high seafloor total organic carbon values at depths greater than 500 meters below sea level near Blake Ridge.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2021)
Article
Geochemistry & Geophysics
Daniel A. Frost, Margaret S. Avery, Bruce A. Buffett, Bethany A. Chidester, Jie Deng, Susannah M. Dorfman, Zhi Li, Lijun Liu, Mingda Lv, Joshua F. Martin
Summary: In this study, an interdisciplinary analysis is used to co-constrain core-mantle boundary heat flow and test the thermal boundary layer theory. The seismic properties consistent with a thermal boundary layer are described, and support for the existence of a long-lived basal mantle molten layer through much of Earth's history is provided.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2022)
Article
Geochemistry & Geophysics
William Davis, Bruce Buffett
Summary: Recent studies have shown that time variations in the Earth's axial magnetic dipole field are influenced by both deterministic and random elements, with the slowest decay mode and turbulent diffusion playing key roles. The amplitude and timescale of variations in dipole field generation, including contributions from both velocity and internal magnetic field variations, also have a significant impact on the field's behavior. Applying these findings to the palaeomagnetic field suggests that reversal rates are highly sensitive to changes in the field generation process.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Geosciences, Multidisciplinary
Rodrigo Chi-Duran, Margaret S. Avery, Bruce A. Buffett
Summary: The acceleration of Earth's magnetic field at high latitudes is attributed to waves in the core, with potential involvement of magnetic Rossby waves and zonal MAC waves. Observations suggest that these waves may propagate within a stratified layer at the top of the core, and the predicted stratification will lead to a slowing down and change in propagation direction of high-latitude features.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Geochemistry & Geophysics
B. A. Buffett, M. S. Avery, W. Davis
Summary: Observations of relative paleointensity reveal various asymmetries in the time dependence of the virtual axial dipole moment (VADM). Stochastic models are used to examine the origin of this behavior, and it is found that a model generating the dipole through a series of impulsive events in time can better explain the observed asymmetry.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2022)
Review
Environmental Sciences
Benjamin W. Abbott, Michael Brown, Joanna C. Carey, Jessica Ernakovich, Jennifer M. Frederick, Laodong Guo, Gustaf Hugelius, Raymond M. Lee, Michael M. Loranty, Robie Macdonald, Paul J. Mann, Susan M. Natali, David Olefeldt, Pam Pearson, Abigail Rec, Martin Robards, Verity G. Salmon, Sayedeh Sara Sayedi, Christina Schadel, Edward A. G. Schuur, Sarah Shakil, Arial J. Shogren, Jens Strauss, Suzanne E. Tank, Brett F. Thornton, Rachael Treharne, Merritt Turetsky, Carolina Voigt, Nancy Wright, Yuanhe Yang, Jay P. Zarnetske, Qiwen Zhang, Scott Zolkos
Summary: Climate change poses a threat to the global permafrost domain, and protecting permafrost ecosystems is crucial for human rights, biosphere integrity, and global climate. Strengthened emissions reduction targets and support for local communities are necessary to preserve intact ecological communities and carbon sinks within the permafrost domain.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Geochemistry & Geophysics
D. Holdenried-Chernoff, B. A. Buffett
Summary: Fluctuations in the paleomagnetic field suggest that the dipole decay time is shorter than expected. The short decay time can be explained by turbulent diffusion, and mean-field theory can quantitatively account for the dynamo results. The predicted decay time depends on the amplitude and length scale of the flow that interacts with the magnetic field. By extending these predictions to the paleomagnetic field, it is found that the inferred decay time requires a bulk root-mean-square velocity less than 0.8-1.2 mm/s.
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS
(2022)
Article
Geochemistry & Geophysics
Quentin Nicolas, Bruce Buffett
Summary: Recent geomagnetic observations show localized oscillations in the field's secular acceleration at high latitudes with a period of about 20 years. This study examines the hypothesis that these observations are the result of MAC waves generated in Earth's core. By evaluating several generation mechanisms using dynamo simulations, the Lorentz force is found to be the most effective in producing high-latitude MAC waves with amplitudes consistent with observed oscillations.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geosciences, Multidisciplinary
Rodrigo Chi-Duran, Bruce A. Buffett
Summary: The rapid growth of magnetic-field observations through SWARM and other satellite missions has led to the development of new approaches for their analysis. The method of dynamic mode decomposition (DMD) is used in this study to analyze the geomagnetic radial field and its secular variation at high latitudes. The analysis reveals five modes, with one representing a slowly evolving background state and the other four describing a pair of waves. These waves have periods of approximately 19.1 and 58.4 years, and their characteristics are consistent with previous predictions and reports.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Physics, Multidisciplinary
Daria Holdenried-Chernoff, David A. King, Bruce A. Buffett
Summary: This paper introduces a stochastic fluid motion model for studying the generation of the geomagnetic field and obtains statistical properties similar to observations. This model helps to understand the long-term evolution of the geomagnetic field.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2023)
Article
Geosciences, Multidisciplinary
Matthias Morzfeld, Bruce A. Buffett
NONLINEAR PROCESSES IN GEOPHYSICS
(2019)
