Including the triple isotopic composition of dissolved oxygen in the ocean into the iLOVECLIM model (version 1.1.7): development and evaluation

By Clermont, Yang, Roche +1Geoscientific model developmentOct 27, 2026

Score████░░░░░░4.4

VerdictWorth a reader's time today.

Abstract

Abstract. Contributing around half of the oxygen produced on Earth, marine photosynthetic production is one of the main mechanisms for carbon fixation, with a central role in the oxygen cycle. The triple isotopic composition of atmospheric oxygen (17Δ), measured in ice cores, provides a global integrator of past biospheric oxygen fluxes, and by extension carbon fluxes. However, deconvolving the signal of 17Δ requires to isolate the oceanic biosphere productivity (17Δocean). Here, we present the first implementation of 17Δocean in the intermediate-complexity climate model iLOVECLIM. The three main processes controlling 17Δocean, i.e. photosynthesis, respiration, and air-sea gas exchange, are explicitly represented and evaluated under preindustrial conditions. Model results show overall good agreement with available measurements, particularly in the Pacific Ocean. In contrast, systematic overestimation is found in the Southern Ocean. At fixed stations, seasonality is reproduced but with underestimated amplitude. These discrepancies mainly reflect challenges in representing remineralization and oxygen minimum zones, and highlight opportunities to refine the representation of primary productivity and vertical mixing. Overall, this new implementation provides the first coupled model framework for simulating 17Δocean, both as a diagnostic of biogeochemical processes and as a tool for reconstructing past changes in marine productivity. Extending the implementation to the terrestrial biosphere will further allow reconstruction of the past global biosphere and direct comparison with 17Δ records from ice cores.

Emeline Clermont, Ji‐Woong Yang, Didier M. Roche, Thomas Extier

The editor's rubric

Heuristic review

Leverage3 / 5: A method or resource many groups across the field will adopt within a year.; 16% of this desk’s rubric
Magnitude3 / 5: Large gain: roughly 2x, or a clear new state of the art on a hard, unsaturated problem.; 20% of this desk’s rubric
Evidence3 / 5: Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.; 20% of this desk’s rubric
Novelty3 / 5: A genuinely new approach to an open problem.; 10% of this desk’s rubric
Trajectory2 / 5: Some room to improve with obvious engineering.; 14% of this desk’s rubric
Stakes3 / 5: Meaningful benefit to many people within a few years.; 20% of this desk’s rubric

Dimension	Level	Weight	What that level means
Leverage	███░░3/5	16%	A method or resource many groups across the field will adopt within a year.
Magnitude	███░░3/5	20%	Large gain: roughly 2x, or a clear new state of the art on a hard, unsaturated problem.
Evidence	███░░3/5	20%	Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.
Novelty	███░░3/5	10%	A genuinely new approach to an open problem.
Trajectory	██░░░2/5	14%	Some room to improve with obvious engineering.
Stakes	███░░3/5	20%	Meaningful benefit to many people within a few years.

Editor’s rationale

Heuristic triage from title and abstract text only, not a reading of the paper. Cues found: method (we propose); firsts (first); verification (error bars, independent replication); stakes (global scale, climate).

How the score was computed

rank-2026-10-18

Score████░░░░░░4.4

Score = 10 × (75% × adjusted merit / 10 + 15% × attention + 10% × freshness)

Desks place stronger verdicts first, then use this score to order work within the same verdict.

Merit: 5.7 / 10; Weighted rubric, evidence-gated.
Adjusted merit: 4.7 / 10; Shrunk toward the desk prior by editor confidence (42%).
Attention: 0%; Citations, upvotes, points, mentions.
Freshness: 85%; Half-life decay since publication.

Citations0 (reference 15, via openalex, Oct 29, 2026, 07:29 UTC)

The record

Reviewed by heuristic-v10 on Oct 29, 2026, 07:29 UTC. Paper type: method.
Categories: Marine and coastal ecosystems, Geology and Paleoclimatology Research, Paleontology and Stratigraphy of Fossils, Oceanography, Earth and Planetary Sciences
TOP, No.2 in the Climate & Energy edition of October 29, 2026.