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Global reorganization of deep-sea circulation and carbon storage after the last ice age.

ABSTRACT: Using new and published marine fossil radiocarbon (¹⁴C/C) measurements, a tracer uniquely sensitive to circulation and air-sea gas exchange, we establish several benchmarks for Atlantic, Southern, and Pacific deep-sea circulation and ventilation since the last ice age. We find the most ¹⁴C-depleted water in glacial Pacific bottom depths, rather than the mid-depths as they are today, which is best explained by a slowdown in glacial deep-sea overturning in addition to a "flipped" glacial Pacific overturning configuration. These observations cannot be produced by changes in air-sea gas exchange alone, and they underscore the major role for changes in the overturning circulation for glacial deep-sea carbon storage in the vast Pacific abyss and the concomitant drawdown of atmospheric CO₂.

SUBMITTER: Rafter PA

PROVIDER: S-EPMC9668286 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature

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Global reorganization of deep-sea circulation and carbon storage after the last ice age.

Rafter Patrick A PA Gray William R WR Hines Sophia K V SKV Burke Andrea A Costa Kassandra M KM Gottschalk Julia J Hain Mathis P MP Rae James W B JWB Southon John R JR Walczak Maureen H MH Yu Jimin J Adkins Jess F JF DeVries Timothy T

Science advances 20221116 46

Using new and published marine fossil radiocarbon (14C/C) measurements, a tracer uniquely sensitive to circulation and air-sea gas exchange, we establish several benchmarks for Atlantic, Southern, and Pacific deep-sea circulation and ventilation since the last ice age. We find the most 14C-depleted water in glacial Pacific bottom depths, rather than the mid-depths as they are today, which is best explained by a slowdown in glacial deep-sea overturning in addition to a "flip ...[more]

PMID: 36383653

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