You are here: Home
/ Publication Information
Title: Is the northern high-latitude land-based CO2 sink weakening?
Author: Hayes, D.J.; McGuire, A.D.; Kicklighter, D.W.; Gurney, K.R.; Burnside, T.J.; Melillo, J.M.
Source: Global Biogeochemical Cycles. 25: GB3018. 14 p. doi: 10.1029/2010GB003813
Description: Studies indicate that, historically, terrestrial ecosystems of the northern high-latitude region may have been responsible for up to 60% of the global net land-based sink for atmospheric C02. However, these regions have recently experienced remarkable modification of the major driving forces of the carbon cycle, including surface air temperature warming that is significantly greater than the global average and associated increases in the frequency and severity of disturbances. Whether Arctic tundra and boreal forest ecosystems will continue to sequester atmospheric C02 in the face of these dramatic changes is unknown. Here we show the results of model simulations that estimate a 41 Tg C yr-1 sink in the boreal land regions from 1997 to 2006, which represents a 73% reduction in the strength of the sink estimated for previous decades in the late 20th century. Our results suggest that C02 uptake by the region in previous decades may not be as strong as previously estimated. The recent decline in sink strength is the combined result of (1) weakening sinks due to warming-induced increases in soil organic matter decomposition and (2) strengthening sources from pyrogenic C02 emissions as a result of the substantial area of boreal forest burned in wildfires across the region in recent years. Such changes create positive feedbacks to the climate system that accelerate global warming, putting further pressure on emission reductions to achieve atmospheric stabilization targets.
Keywords: carbon, climate change, boreal
View or Print this Publication (1.3 MB)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
Hayes, D.J.; McGuire, A.D.; Kicklighter, D.W.; Gurney, K.R.; Burnside, T.J.; Melillo, J.M. 2011. Is the northern high-latitude land-based CO2 sink weakening? Global Biogeochemical Cycles. 25: GB3018. 14 p. doi:10.1029/2010GB003813.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility