Bounding cross-shelf transport time and degradation in Siberian-Arctic land-ocean carbon transfer

Details

• Journal Title:
  Nature Communications
• Personal Author:
  Bröder, Lisa ; Tesi, Tommaso ; Andersson, August ; Semiletov, Igor ; Gustafsson, Örjan
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; CPO (Climate Program Office)
• Description:
  The burial of terrestrial organic carbon (terrOC) in marine sediments contributes to the regulation of atmospheric CO2 on geological timescales and may mitigate positive feedback to present-day climate warming. However, the fate of terrOC in marine settings is debated, with uncertainties regarding its degradation during transport. Here, we employ compound-specific radiocarbon analyses of terrestrial biomarkers to determine cross-shelf transport times. For the World’s largest marginal sea, the East Siberian Arctic shelf, transport requires 3600 ± 300 years for the 600 km from the Lena River to the Laptev Sea shelf edge. TerrOC was reduced by ~85% during transit resulting in a degradation rate constant of 2.4 ± 0.6 kyr−1. Hence, terrOC degradation during cross-shelf transport constitutes a carbon source to the atmosphere over millennial time. For the contemporary carbon cycle on the other hand, slow terrOC degradation brings considerable attenuation of the decadal-centennial permafrost carbon-climate feedback caused by global warming.
• Keywords:
  Climatic Changes Organic Compounds Climatic Changes Organic Compounds
• Source:
  Nat Commun. 2018; 9: 806.
• DOI:
  https://doi.org/10.1038/s41467-018-03192-1
• Pubmed ID:
  29476050
• Pubmed Central ID:
  PMC5824890
• Document Type:
  Journal Article
• Funding:
  Grant no. NA08OAR4600758
• Rights Information:
  CC BY
• Compliance:
  PMC
• Main Document Checksum:
  urn:sha256:f7380e8af837a5c70904e24a563f58fb45e0c36b9a2dadd43e0516909565ff1a
• Download URL:
  https://repository.library.noaa.gov/view/noaa/27608/noaa_27608_DS1.pdf
• File Type:
  [PDF - 1.62 MB ]