An improved comparison of atmospheric Ar/N2 time-series and paired ocean-atmosphere model predictions


Journal Article

Ar/N2 variations in the atmosphere reflect ocean heat fluxes, air-sea gas exchange, and atmospheric dynamics. Here atmospheric Ar/N2 time series are compared to paired ocean-atmosphere model predictions. Agreement between Ar/N2 observations and simulations has improved in comparison to a previous study because of longer time series and the introduction of automated samplers at several of the atmospheric stations, as well as the refinement of the paired ocean-atmosphere models by inclusion of Ar and N2 as active tracers in the ocean component. Although analytical uncertainties and collection artifacts are likely to be mainly responsible for observed Ar/N2 outliers, air parcel back-trajectory analysis suggests that some of the variability in Ar/N2 measurements could be due to the low-altitude history of the air mass collected and, by extension, the local oceanic Ar/N2 signal. Although the simulated climatological seasonal cycle can currently be evaluated with Ar/N2 observations, longer time series and additional improvements in the signal-to-noise ratio will be required to test other model predictions such as interannual variability, latitudinal gradients, and the secular increase in atmospheric Ar/N2 expected to result from ocean warming. Copyright 2008 by the American Geophysical Union.

Full Text

Duke Authors

Cited Authors

  • Cassar, N; McKinley, GA; Bender, ML; Mika, R; Battle, M

Published Date

  • November 16, 2008

Published In

Volume / Issue

  • 113 / D21

Published By

International Standard Serial Number (ISSN)

  • 0148-0227

Digital Object Identifier (DOI)

  • 10.1029/2008JD009817