Charcoal Fluxes into Sediments of the North Pacific Ocean: The Cenozoic Record of Burning

  1. E.T. Sundquist and
  2. W.S. Broecker
  1. James R. Herring

Published Online: 18 MAR 2013

DOI: 10.1029/GM032p0419

The Carbon Cycle and Atmospheric CO: Natural Variations Archean to Present

The Carbon Cycle and Atmospheric CO: Natural Variations Archean to Present

How to Cite

Herring, J. R. (1985) Charcoal Fluxes into Sediments of the North Pacific Ocean: The Cenozoic Record of Burning, in The Carbon Cycle and Atmospheric CO: Natural Variations Archean to Present (eds E.T. Sundquist and W.S. Broecker), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM032p0419

Author Information

  1. U.S. Geological Survey, Lakewood, Colorado 80226

Publication History

  1. Published Online: 18 MAR 2013
  2. Published Print: 1 JAN 1985

ISBN Information

Print ISBN: 9780875900605

Online ISBN: 9781118664322

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Keywords:

  • Carbon cycle (Biogeochemistry)—Congresses;
  • Atmospheric carbon dioxide—Congresses;
  • Geological time—Congresses;
  • Paleothermometry—Congresses;
  • Geology, Stratigraphic—Congresses

Summary

Charcoal particles occur in sediments of the North Pacific Ocean at least as old as the earliest Cenozoic. The particles have morphologies similar to those from modern trees and shrubs. The charcoal results from plant burning on land; particles subsequently were blown into the ocean. This study measured charcoal concentrations in Cenozoic sediments from 11 Deep Sea Drilling Project sites. Although the charcoal concentrations in Holocene sediments vary considerably, they are consistently greater at temperate and high latitudes than at low latitudes. At each site, Holocene sediment charcoal concentrations also are consistently greater than older sediments at each site. Fluxes of charcoal to the sediment (mass per unit area per unit time) were calculated from the charcoal concentrations and the sediment accumulation rates. Through the Paleogene the charcoal flux remained small; but in the Neogene (at most sites, in the Miocene) the fluxes began to increase, and since the late Neogene the fluxes have been approximately two orders of magnitude greater than in the Paleogene. The increase appears to be real: there has been no chemical or biological destruction of the charcoal, which would cause older fluxes to appear smaller. The size distribution of the charcoal particles, which would be reduced by such destruction, shows no consistent trend through the sediment column. Much of the increased charcoal flux into upper Cenozoic sediments appears to be due to increased plant burning on land; the rest to increased wind transport of the charcoal from land to the ocean. An increase in burning is consistent with paleobotanical and paleoclimatic evidence, which indicates that an increasingly cool climate throughout the Cenozoic increased the relative abundance of temperate, hence more burnable, plants. The amount of burning in turn changed because of changes in the abundance of burnable plants or changes in combustion conditions affected by relative humidity, temperature, or oxygen-nitrogen concentration in the atmosphere. Over the past 5 million years, the estimate for the permanent removal of carbon from the atmosphere as inert charcoal is approximately 1014 g, or about 0.01% of the present atmosphere carbon mass, per year.