Simulating Deglacial Radiocarbon Anomalies With pH‐Neutral Geologic Carbon
Year: 2026
Type: article
Abstract: There is currently no explanation or carbon cycle model scenario for severe radiocarbon ( 14 C) depletion reconstructed in the intermediate depth eastern tropical North Pacific Ocean (ETNP) at the end of the last ice age. Here, we develop new constraints on hypothesized geologic carbon release based on the boron isotope pH proxy and regional refinement of a global carbon cycle model. We find that pH‐neutral release of ∼800 Pg C over 5,000 years can produce the radiocarbon anomalies in the ETNP while inducing neither a large pH anomaly nor CaCO 3 dissolution (as observed) and causing minimal atmospheric CO 2 rise. Mass‐balance considerations dictate that the anomalous carbon was concentrated near the geologic source in the ETNP without significantly affecting radiocarbon‐based reconstructions of global ocean circulation change.
DOI: 10.1029/2025pa005217
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: green
Funder: National Science Foundation
Awards: RCN: Improving reconstructions of Cenozoic pCO2 and temperature change, Collaborative Research: Characterizing Northern Hemisphere Atmospheric Variability from Central American Wind Gap-Induced Upwelling, Collaborative Research: Was there an anomalous Indian Ocean carbon reservoir? Searching for old radiocarbon and quantifying Ice Age changes in deep Indian Ocean ventilation, Collaborative Research: Uncovering marine carbon chemistry dynamics during the deglaciation with boron isotopes and radiocarbon
OpenAlex ID: W7160420202