OS Ocean Science OS Ocean Sci. 1812-0792 Copernicus Publications Göttingen, Germany 10.5194/os-6-381-2010 Sediment <sup>231</sup>Pa/<sup>230</sup>Th as a recorder of the rate of the Atlantic meridional overturning circulation: insights from a 2-D model Luo Y. 1 Francois R. 1 Allen S. E. 1 Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, BC, V6T 1Z4, Canada 19 03 2010 6 1 381 400 Copyright: © 2010 Y. Luo et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://os.copernicus.org/articles/6/381/2010/os-6-381-2010.html The full text article is available as a PDF file from https://os.copernicus.org/articles/6/381/2010/os-6-381-2010.pdf

A two dimensional scavenging model is used to investigate the patterns of sediment <sup>231</sup>Pa/<sup>230</sup>Th generated by the Atlantic Meridional Overturning Circulation (AMOC) and further advance the application of this proxy for ocean paleocirculation studies. The scavenging parameters and the geometry of the overturning circulation cell have been chosen so that the model generates meridional sections of dissolved <sup>230</sup>Th and <sup>231</sup>Pa consistent with published water column profiles and an additional 12 previously unpublished profiles measured in the North and Equatorial Atlantic. The processes that generate the meridional sections of dissolved and particulate <sup>230</sup>Th, dissolved and particulate <sup>231</sup>Pa, dissolved and particulate <sup>231</sup>Pa/<sup>230</sup>Th, and sediment <sup>231</sup>Pa/<sup>230</sup>Th are discussed in detail. The results indicate that the relationship between sediment <sup>231</sup>Pa/<sup>230</sup>Th at any given site and the overturning circulation is very complex. They clearly show that constraining past changes in the strength and geometry of the AMOC requires an extensive data set and they suggest strategies to maximize information from a limited number of samples.

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