This paper reveals a previously unrecognized bias in the marine sediment record, challenging conventional interpretations of long-term carbon sequestration and weathering trends. While biases in the fossil and geological records are well-studied, this study demonstrates that deep-sea sedimentation data are also systematically skewed, necessitating a critical reevaluation of widely used paleoceanographic proxies. As a comprehensive meta-analysis of marine core data, these findings have far-reaching implications, highlighting the need to account for age-dependent biases in sedimentation-related proxies to refine our understanding of Earth's past climate and carbon cycle dynamics.

This study presents new insights into autotrophic carbon fixation in shallow-water hydrothermal systems, emphasizing the dominance of reductive tricarboxylic acid (rTCA) cycle-utilizing Campylobacteria. Low isotopic fractionation values in vent fluids, possibly due to very acidic pH levels, extend the isotopic fractionation range of rTCA. The study also highlights the ecological significance of chemosynthetically fixed carbon, observed in higher trophic levels like the vent endemic crab Xenograpsus testudinatus, improving our understanding of carbon cycling in extreme environments and the interplay between microbial chemosynthesis and higher organisms.

The ocean plays a key role in the global carbon cycle and its carbon sink strength is critical for removing atmospheric carbon dioxide and stabilizing global climate. This oceanic carbon sink strength is difficult to measure and models provide estimates that differ from one another. Terhaar combines multiple modeling approaches using composite model-based averages and fully coupled Earth System Models to take advantages of the benefits of both, and in doing so derives a similar sink strength to existing estimates but with reduced uncertainty.