Jennifer Harden, PhD (Former Employee)
Science and Products
Filter Total Items: 144
Estimating heterotrophic respiration at large scales: Challenges, approaches, and next steps Estimating heterotrophic respiration at large scales: Challenges, approaches, and next steps
Heterotrophic respiration (HR), the aerobic and anaerobic processes mineralizing organic matter, is a key carbon flux but one impossible to measure at scales significantly larger than small experimental plots. This impedes our ability to understand carbon and nutrient cycles, benchmark models, or reliably upscale point measurements. Given that a new generation of highly mechanistic...
Authors
Ben Bond-Lamberty, Daniel Epron, Jennifer W. Harden, Mark E. Harmon, Forrest Hoffman, Jitendra Kumar, Anthony D. McGuire, Rodrigo Vargas
Effects of permafrost aggradation on peat properties as determined from a pan-Arctic synthesis of plant macrofossils Effects of permafrost aggradation on peat properties as determined from a pan-Arctic synthesis of plant macrofossils
Permafrost dynamics play an important role in high-latitude peatland carbon balance and are key to understanding the future response of soil carbon stocks. Permafrost aggradation can control the magnitude of the carbon feedback in peatlands through effects on peat properties. We compiled peatland plant macrofossil records for the northern permafrost zone (515 cores from 280 sites) and...
Authors
Claire C. Treat, Miriam C. Jones, P. Camill, A. Gallego-Sala, M. Garneau, Jennifer W. Harden, G. Hugelius, E.S. Klein, Ulla Kokfelt, P. Kuhry, Julie Loisel, J.H. Mathijssen, J.A. O'Donnell, P.O. Oksanen, T.M. Ronkainen, A. B. K. Sannel, J. J. Talbot, C.M. Tarnocal, M. Valiranta
Toward more realistic projections of soil carbon dynamics by Earth system models Toward more realistic projections of soil carbon dynamics by Earth system models
Soil carbon (C) is a critical component of Earth system models (ESMs), and its diverse representations are a major source of the large spread across models in the terrestrial C sink from the third to fifth assessment reports of the Intergovernmental Panel on Climate Change (IPCC). Improving soil C projections is of a high priority for Earth system modeling in the future IPCC and other...
Authors
Y. Luo, Anders Ahlstrom, Steven D. Allison, Niels H. Batjes, V. Brovkin, Nuno Carvalhais, Adrian Chappell, Philippe Ciais, Eric A. Davidson, Adien Finzi, Katerina Georgiou, Bertrand Guenet, Oleksandra Hararuk, Jennifer Harden, Yujie He, Francesca Hopkins, L. Jiang, Charles Koven, Robert B. Jackson, Chris D. Jones, M. Lara, J. Liang, A. David McGuire, William Parton, Changhui Peng, J. Randerson, Alejandro Salazar, Carlos A. Sierra, Matthew J. Smith, Hanqin Tian, Katherine E. O Todd-Brown, Margaret S. Torn, Kees Jan van Groenigen, Ying Wang, Tristram O. West, Yaxing Wei, William R. Wieder, Jianyang Xia, Xia Xu, Xiaofeng Xu, T. Zhou
Differential response of carbon fluxes to climate in three peatland ecosystems that vary in the presence and stability of permafrost Differential response of carbon fluxes to climate in three peatland ecosystems that vary in the presence and stability of permafrost
Changes in vegetation and soil properties following permafrost degradation and thermokarst development in peatlands may cause changes in net carbon storage. To better understand these dynamics, we established three sites in Alaska that vary in permafrost regime, including a black spruce peat plateau forest with stable permafrost, an internal collapse scar bog formed as a result of...
Authors
Eugenie S. Euskirchen, C.W. Edgar, M.R. Turetsky, Mark P. Waldrop, Jennifer W. Harden
A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback
We present an approach to estimate the feedback from large-scale thawing of permafrost soils using a simplified, data-constrained model that combines three elements: soil carbon (C) maps and profiles to identify the distribution and type of C in permafrost soils; incubation experiments to quantify the rates of C lost after thaw; and models of soil thermal dynamics in response to climate...
Authors
C.D. Koven, E.A.G. Schuur, C. Schädel, T. J. Bohn, E. J. Burke, G. Chen, X. Chen, P. Ciais, G. Grosse, J.W. Harden, D.J. Hayes, G. Hugelius, Elchin E. Jafarov, G. Krinner, P. Kuhry, D.M. Lawrence, A. H. MacDougall, Sergey S. Marchenko, A. David McGuire, Susan M. Natali, D.J. Nicolsky, David Olefeldt, S. Peng, V.E. Romanovsky, Kevin M. Schaefer, J. Strauss, Claire C. Treat, M. Turetsky
Climate change and the permafrost carbon feedback Climate change and the permafrost carbon feedback
Large quantities of organic carbon are stored in frozen soils (permafrost) within Arctic and sub-Arctic regions. A warming climate can induce environmental changes that accelerate the microbial breakdown of organic carbon and the release of the greenhouse gases carbon dioxide and methane. This feedback can accelerate climate change, but the magnitude and timing of greenhouse gas emission...
Authors
E.A.G. Schuur, A. David McGuire, C. Schädel, G. Grosse, J.W. Harden, D.J. Hayes, G. Hugelius, C.D. Koven, P. Kuhry, D.M. Lawrence, Susan M. Natali, David Olefeldt, V.E. Romanovsky, K. Schaefer, M.R. Turetsky, Claire C. Treat, J.E. Vonk
Science and Products
Filter Total Items: 144
Estimating heterotrophic respiration at large scales: Challenges, approaches, and next steps Estimating heterotrophic respiration at large scales: Challenges, approaches, and next steps
Heterotrophic respiration (HR), the aerobic and anaerobic processes mineralizing organic matter, is a key carbon flux but one impossible to measure at scales significantly larger than small experimental plots. This impedes our ability to understand carbon and nutrient cycles, benchmark models, or reliably upscale point measurements. Given that a new generation of highly mechanistic...
Authors
Ben Bond-Lamberty, Daniel Epron, Jennifer W. Harden, Mark E. Harmon, Forrest Hoffman, Jitendra Kumar, Anthony D. McGuire, Rodrigo Vargas
Effects of permafrost aggradation on peat properties as determined from a pan-Arctic synthesis of plant macrofossils Effects of permafrost aggradation on peat properties as determined from a pan-Arctic synthesis of plant macrofossils
Permafrost dynamics play an important role in high-latitude peatland carbon balance and are key to understanding the future response of soil carbon stocks. Permafrost aggradation can control the magnitude of the carbon feedback in peatlands through effects on peat properties. We compiled peatland plant macrofossil records for the northern permafrost zone (515 cores from 280 sites) and...
Authors
Claire C. Treat, Miriam C. Jones, P. Camill, A. Gallego-Sala, M. Garneau, Jennifer W. Harden, G. Hugelius, E.S. Klein, Ulla Kokfelt, P. Kuhry, Julie Loisel, J.H. Mathijssen, J.A. O'Donnell, P.O. Oksanen, T.M. Ronkainen, A. B. K. Sannel, J. J. Talbot, C.M. Tarnocal, M. Valiranta
Toward more realistic projections of soil carbon dynamics by Earth system models Toward more realistic projections of soil carbon dynamics by Earth system models
Soil carbon (C) is a critical component of Earth system models (ESMs), and its diverse representations are a major source of the large spread across models in the terrestrial C sink from the third to fifth assessment reports of the Intergovernmental Panel on Climate Change (IPCC). Improving soil C projections is of a high priority for Earth system modeling in the future IPCC and other...
Authors
Y. Luo, Anders Ahlstrom, Steven D. Allison, Niels H. Batjes, V. Brovkin, Nuno Carvalhais, Adrian Chappell, Philippe Ciais, Eric A. Davidson, Adien Finzi, Katerina Georgiou, Bertrand Guenet, Oleksandra Hararuk, Jennifer Harden, Yujie He, Francesca Hopkins, L. Jiang, Charles Koven, Robert B. Jackson, Chris D. Jones, M. Lara, J. Liang, A. David McGuire, William Parton, Changhui Peng, J. Randerson, Alejandro Salazar, Carlos A. Sierra, Matthew J. Smith, Hanqin Tian, Katherine E. O Todd-Brown, Margaret S. Torn, Kees Jan van Groenigen, Ying Wang, Tristram O. West, Yaxing Wei, William R. Wieder, Jianyang Xia, Xia Xu, Xiaofeng Xu, T. Zhou
Differential response of carbon fluxes to climate in three peatland ecosystems that vary in the presence and stability of permafrost Differential response of carbon fluxes to climate in three peatland ecosystems that vary in the presence and stability of permafrost
Changes in vegetation and soil properties following permafrost degradation and thermokarst development in peatlands may cause changes in net carbon storage. To better understand these dynamics, we established three sites in Alaska that vary in permafrost regime, including a black spruce peat plateau forest with stable permafrost, an internal collapse scar bog formed as a result of...
Authors
Eugenie S. Euskirchen, C.W. Edgar, M.R. Turetsky, Mark P. Waldrop, Jennifer W. Harden
A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback
We present an approach to estimate the feedback from large-scale thawing of permafrost soils using a simplified, data-constrained model that combines three elements: soil carbon (C) maps and profiles to identify the distribution and type of C in permafrost soils; incubation experiments to quantify the rates of C lost after thaw; and models of soil thermal dynamics in response to climate...
Authors
C.D. Koven, E.A.G. Schuur, C. Schädel, T. J. Bohn, E. J. Burke, G. Chen, X. Chen, P. Ciais, G. Grosse, J.W. Harden, D.J. Hayes, G. Hugelius, Elchin E. Jafarov, G. Krinner, P. Kuhry, D.M. Lawrence, A. H. MacDougall, Sergey S. Marchenko, A. David McGuire, Susan M. Natali, D.J. Nicolsky, David Olefeldt, S. Peng, V.E. Romanovsky, Kevin M. Schaefer, J. Strauss, Claire C. Treat, M. Turetsky
Climate change and the permafrost carbon feedback Climate change and the permafrost carbon feedback
Large quantities of organic carbon are stored in frozen soils (permafrost) within Arctic and sub-Arctic regions. A warming climate can induce environmental changes that accelerate the microbial breakdown of organic carbon and the release of the greenhouse gases carbon dioxide and methane. This feedback can accelerate climate change, but the magnitude and timing of greenhouse gas emission...
Authors
E.A.G. Schuur, A. David McGuire, C. Schädel, G. Grosse, J.W. Harden, D.J. Hayes, G. Hugelius, C.D. Koven, P. Kuhry, D.M. Lawrence, Susan M. Natali, David Olefeldt, V.E. Romanovsky, K. Schaefer, M.R. Turetsky, Claire C. Treat, J.E. Vonk
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government