Throughout the deglaciation, the Pacific Ocean circulation in C‐iTRACE responds strongly to glacial meltwater forcing, leading to large changes in deep Pacific Δ¹⁴C age. Here we use the C‐iTRACE simulation, a transient ocean‐only, isotope‐enabled version of the Community Earth System Model, to better understand deglacial deep Pacific radiocarbon evolution in the context of circulation and reservoir age changes. Although proxy records have significantly improved our understanding of climate during this period, questions remain regarding the connection between ocean circulation evolution and resulting geotracer distributions, including those of deep waters in the Pacific. AMOC = Atlantic Meridional Overturning Circulation LGM = Last Glacial Maximum.ĭuring the last deglaciation Earth’s climate experienced strong and abrupt variations, resulting in major changes in global temperature, sea level, and ocean circulation. (f) δ¹⁸Oc distribution at 530 m during LGM in C‐iTRACE, with velocity overlaid as vectors. (e) The Sverdrup transport in the Florida Straits in C‐iTRACE. (d)The average meridional velocity at 530 m in the Florida Straits (orange), the Florida Current transport (purple), and the maximum of the Atlantic meridional overturning stream function at 24.5°N (red). (c) δ¹⁸Oc contrast (black) and density contrast (magenta) between the two Florida Straits sites in C‐iTRACE. (2014) is shown as black circles, and the location of the model grids for these two observational sites are shown as magenta triangles in (f). The location of the two observational sites in Lynch‐Stieglitz et al. Dots are observations (Lynch‐Stieglitz et al., 2014), and curves are model results. (b) δ¹⁸Oc evolution from two cores located on either side of the Florida Current (blue for the west site red for the east site). The strength of AMOC is defined as the maximum of the Atlantic meridional overturning stream function below 500 m between 30°N and 60°N (in Sverdrup, Sv). (a) AMOC strength (black) and observational (red dot McManus et al., 2004) and model (red curve) ²³¹Pa/²³⁰Th from site OCE326‐GGC5 (33☄2′N, 57☃5′W, 4.55 km). Time evolutions in the Florida Straits and the d¹⁸Oc distribution in C‐iTRACE.
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