Can paleoceanographic tracers constrain meridional circulation rates?
Gebbie, Geoffrey A.
MetadataShow full item record
The ability of paleoceanographic tracers to constrain rates of transport is examined using an inverse method to combine idealized observations with a geostrophic model. Considered are the spatial distribution, accuracy, and types of tracers required to constrain changes in meridional transport within an idealized single-hemisphere basin. Measurements of density and radioactive tracers each act to constrain rates of transport. Conservative tracers, while not of themselves able to inform regarding rates of transport, improve constraints when coupled with density or radioactive observations. It is found that the tracer data would require an accuracy one order of magnitude better than is presently available for paleo-observations to conclusively rule out factor-of-2 changes in meridional transport, even when assumed available over the entire model domain. When data are available only at the margins and bottom of the model, radiocarbon is unable to constrain transport while density remains effective only when a reference velocity level is assumed. The difficulty in constraining the circulation in this idealized model indicates that placing firm bounds on past meridional transport rates will prove challenging.
Author Posting. © American Meteorological Society, 2007. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 37 (2007): 394-407, doi:10.1175/jpo3018.1.
Showing items related by title, author, creator and subject.
Mixing in the North Atlantic Tracer Release Experiment : observations and numerical simulations of Lagrangian particles and passive tracer Sundermeyer, Miles A. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1995-09)Mixing and stirring of passive tracer and Lagrangian particles in the open ocean was studied through comparison of observations from the North Atlantic Tracer Release Experiment, a numerical model, and existing theory. ...
Fate of nitrogen in riparian forest soils and trees : an N-15 tracer study simulating salmon decay Drake, Deanne C.; Naiman, Robert J.; Bechtold, J. Scott (2005-05-23)We introduced a 15N-NH4+ tracer to the riparian forest of a salmon-bearing stream (Kennedy Creek, Washington, USA) to quantify the cycling and fate of a late-season pulse of salmon-N, and, ultimately, mechanisms regulating ...
Ho, David T.; Ledwell, James R.; Smethie, William M. (American Geophysical Union, 2008-02-19)SF6 tracer release experiments (TREs) have provided fundamental insights in many areas of Oceanography. Recently, SF6 has emerged as a powerful transient tracer, generating a need for an alternative tracer for large-scale ...