Influence of marine denitrification on atmospheric N2O variability during the Holocene

Abstract

Oceanic denitrification centers are thought to be important marine sources for atmospheric N2O. To consider Holocene variability in this source, we reconstruct the Holocene paleo-denitrification history of the Peru margin, a major marine denitrification center, using high-resolution sedimentary δ15N data. This record along with a contemporaneous one from the western Arabian Sea (Altabet et al., 2002) shows similarities with the recently available high-resolution atmospheric N2O record (Flückiger et al., 2002). While the role of terrestrial processes in the observed N2O changes remains uncertain, these results suggest that variability in marine denitrification in major upwelling centers such as the Peru margin and the Arabian Sea contributed significantly to atmospheric N 2O evolution during the Holocene. Copyright 2006 by the American Geophysical Union.