edu.ucar.opensky::articles:17776 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T03:00:15.008707 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7fb54dj A simplified, data-constrained approach to estimate the permafrost carbon–climate feedback 2015-11-01T00:00:00Z publication https://n2t.org/ark:/85065/d7fb54dj https://doi.org/10.1098/rsta.2014.0423 Koven, C. author Schuur, E. author Schädel, C. author Bohn, T. author Burke, E. author Chen, G. author Chen, X. author Ciais, P. author Grosse, G. author Harden, J. author Hayes, J. author Hugelius, G. author Jafarov, E. author Krinner, G. author Kuhry, P. author Lawrence, David M. author MacDougall, A. author Marchenko, S. author McGuire, A. author Natali, S. author Nicolsky, D. author Olefeldt, D. author Peng, S. author Romanovsky, V. author Schaefer, K. author Strauss, J. author Treat, C. author Turetsky, M. author UCAR/NCAR - Library publisher 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 warming. We call the approach the Permafrost Carbon Network Incubation-Panarctic Thermal scaling approach (PInc-PanTher). The approach assumes that C stocks do not decompose at all when frozen, but once thawed follow set decomposition trajectories as a function of soil temperature. The trajectories are determined according to a three-pool decomposition model fitted to incubation data using parameters specific to soil horizon types. We calculate litterfall C inputs required to maintain steady-state C balance for the current climate, and hold those inputs constant. Soil temperatures are taken from the soil thermal modules of ecosystem model simulations forced by a common set of future climate change anomalies under two warming scenarios over the period 2010 to 2100. Under a medium warming scenario (RCP4.5), the approach projects permafrost soil C losses of 12.2-33.4 Pg C; under a high warming scenario (RCP8.5), the approach projects C losses of 27.9-112.6 Pg C. Projected C losses are roughly linearly proportional to global temperature changes across the two scenarios. These results indicate a global sensitivity of frozen soil C to climate change (γ sensitivity) of -14 to -19 Pg C °C⁻¹ on a 100 year time scale. For CH₄ emissions, our approach assumes a fixed saturated area and that increases in CH₄ emissions are related to increased heterotrophic respiration in anoxic soil, yielding CH₄ emission increases of 7% and 35% for the RCP4.5 and RCP8.5 scenarios, respectively, which add an additional greenhouse gas forcing of approximately 10-18%. The simplified approach presented here neglects many important processes that may amplify or mitigate C release from permafrost soils, but serves as a data-constrained estimate on the forced, large-scale permafrost C response to warming. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright Author(s) 2015. None eng geoscientificInformation