The impacts of recent permafrost thaw on land–atmosphere greenhouse gas exchange

Datos Bibliográficos

ID15547804
AutoresDaniel J Hayes (0000-0002-3011-7934, Oak Ridge National Laboratory, autor de correspondencia), David W Kicklighter (0000-0001-6820-2651, Marine Biological Laboratory), A D McGuire (University of Alaska Fairbanks), Min Chen (0000-0001-8922-8789, Purdue University West Lafayette), Qianlai Zhuang (0000-0002-4536-9851, Purdue University West Lafayette), Fengming Yuan (0000-0003-0910-5231, Oak Ridge National Laboratory), Jerry M Melillo (0000-0002-4295-5396, Marine Biological Laboratory), Stan D Wullschleger (0000-0002-9869-0446, Oak Ridge National Laboratory)
Año2014
Volumen9
Número4
Páginas045005-045005
Fecha de publicación2014-04-01
Peer ReviewedSí
Open AccessSí
TipoARTICLE
RevistaEnvironmental Research Letters (JOURNAL)
Identificadores de la revistaISSN: 1748-9326 • E-ISSN: 1748-9326
EditorialIOP Publishing (PUBLISHER • GB)
DOI10.1088/1748-9326/9/4/045005
OpenAlexW1965495157
IdiomaEN
Citas recibidas7
Referencias citadas3

Permafrost thaw and the subsequent mobilization of carbon (C) stored in previously frozen soil organic matter (SOM) have the potential to be a strong positive feedback to climate. As the northern permafrost region experiences as much as a doubling of the rate of warming as the rest of the Earth, the vast amount of C in permafrost soils is vulnerable to thaw, decomposition and release as atmospheric greenhouse gases. Diagnostic and predictive estimates of high-latitude terrestrial C fluxes vary widely among different models depending on how dynamics in permafrost, and the seasonally thawed 'active layer' above it, are represented. Here, we employ a process-based model simulation experiment to assess the net effect of active layer dynamics on this 'permafrost carbon feedback' in recent decades, from 1970 to 2006, over the circumpolar domain of continuous and discontinuous permafrost. Over this time period, the model estimates a mean increase of 6.8 cm in active layer thickness across the domain, which exposes a total of 11.6 Pg C of thawed SOM to decomposition. According to our simulation experiment, mobilization of this previously frozen C results in an estimated cumulative net source of 3.7 Pg C to the atmosphere since 1970 directly tied to active layer dynamics. Enhanced decomposition from the newly exposed SOM accounts for the release of both CO 2 (4.0 Pg C) and CH 4 (0.03 Pg C), but is partially compensated by CO 2 uptake (0.3 Pg C) associated with enhanced net primary production of vegetation. This estimated net C transfer to the atmosphere from permafrost thaw represents a significant factor in the overall ecosystem carbon budget of the Pan-Arctic, and a non-trivial additional contribution on top of the combined fossil fuel emissions from the eight Arctic nations over this time period

Active layer · Atmosphere (unit · Atmospheric sciences · Climate change · Climatology · Ecosystem · Geography · Greenhouse gas · Latitude · Layer (electronics · Meteorology · Permafrost · Primary production · Soil water · Vegetation (pathology · Chemistry · Climate change and permafrost · Cryospheric studies and observations · Environmental Science · Geology and Paleoclimatology Research · Ecology · Geology · Oceanography · Soil Science