The DOI matches its Crossref record; 54 of the 55 references it cites were found in a registry or an index; 12 of the 45 sources its claims cite were checked for support.
Regulation of atmospheric CO 2 by deep‐sea sediments in an Earth system model
Open accessAbstract
We have extended the GENIE‐1 Earth system model to include a representation of sedimentary stratigraphy and the preservation of biogenic carbonates delivered to the ocean floor. This has enabled us to take a novel approach in diagnosing modern marine carbon cycling: assimilating observation of the calcium carbonate (CaCO 3 ) content of deep‐sea sediments with an ensemble Kalman filter. The resulting calibrated model predicts a mean surface sediment content (32.5 wt%) close to the observed value (34.8 wt%), and a global burial rate of CaCO 3 in deep sea sediments of 0.121 PgC yr −1 , in line with recent budget estimates of 0.10−0.14 PgC yr −1 . We employ the GENIE‐1 model in quantifying the multimillennial‐scale fate of fossil fuel CO 2 emitted to the atmosphere. In the absence of any interaction between ocean and sediments, an equilibrium partitioning of CO 2 is reached within ∼1000 years of emissions ceasing, with 34% (645 ppm) remaining in the atmosphere out of a total fossil fuel burn of 4173 PgC. An additional 12% of CO 2 emissions (223 ppm) are sequestered as bicarbonate ions (HCO 3 − ) by reaction with deep‐sea carbonates (“seafloor CaCO 3 neutralization”) on a timescale of ∼1.7 ka. Excess of carbonate weathering on land over deep‐sea burial results in a further net transformation of 14% of CO 2 emissions (261 ppm) into HCO 3 − (“terrestrial CaCO 3 neutralization”) on a timescale of ∼8.3 ka. We have also assessed the importance of a changing climate in modulating the stabilization of atmospheric CO 2 through ocean‐sediment interaction. Increased ocean stratification suppresses particulate organic carbon export, which in turn enhances seafloor CaCO 3 preservation. The resulting reduction in the sequestration of fossil fuel CO 2 represents a new positive feedback on millennial‐scale climate change.
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Claims the paper makes
30 Own result · 16 Own interpretation · 13 No full text of the sources · 13 No basis given · 5 Supported so far · 3 Supported · 3 Partly supported · 2 Not checked yet · 2 Own method · 1 Sources not found · accuracy not yet measured
Every source the paper cites for this claim was checked and supports it.
In the paper
“because of large uncertainties in model structure, meaning that the model is known a priori to be a far from perfect model, using the full ensemble results to provide probabilistic estimates of model variables or parameters would not be a valid approach, as discussed by Ridgwell et al. [2007].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 3. Data Assimilation and Calibration of Ocean-Sediment Carbon Cycling
What the sources say
- Supportedcites Ridgwell et al. [2007] source
Section 3.1 (p. 9) says ensemble spread indicates uncertainty only when all uncertainties are well defined. Because the paper’s model parameterizations may be inadequate, the authors say they cannot estimate the calibrated model’s true uncertainty and instead use the ensemble mean as a single best parameter set. (LLM, conf=0.92)
plaindirect- Asserted: passes — The authors put it forward as true.
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- Supported
Every source the paper cites for this claim was checked and supports it.
In the paper
“The improvement in wt% CaCO 3 afforded by the addition of 2-D sediment data in the EnKF resulted in only a very slight degradation in the quality of alkalinity and phosphate fields compared to observations, less than 1% increase in the mean square difference between the data and the model fields compared to that presented by Ridgwell et al. [2007].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 4. Present-Day Global Carbonate Cycling
What the sources say
- Supportedcites Ridgwell et al. [2007] source
The citation identifies Ridgwell et al. (2007) as the comparison baseline, not as the source of the later study’s less-than-1% result. Section 3.1 (pp. 8–9) describes Ridgwell et al.’s EnKF calibration against observed alkalinity and phosphate fields, supporting that use of the citation. (LLM, conf=0.88)
plaindirect- Asserted: passes — The authors put it forward as true.
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- Supported
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In the paper
“Previous analysis of the role of deep-sea sediments in the long-term fate of fossil fuel CO 2 employed off-line tracer-transport marine carbon cycle models in which the ocean circulation was prescribed [e.g., Archer et al., 1997Archer et al., , 1998;;Sundquist, 1990].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Not checked — no full text of the sourcecites Archer et al., 1997 source
- Partly supportedcites Archer et al., 1998 sourceExperimental — accuracy not yet measured
The Model Description (page unavailable) says the authors coupled an ocean-circulation and water-column chemistry model to a deep-sea sediment model, supporting the citation as an example of the stated research. It does not specify that the model was off-line or that ocean circulation was prescribed; searches for those terms did not establish that methodological detail. (LLM, conf=0.82)
- Not checked — no full text of the sourcecites Sundquist, 1990 source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Because the GENIE-1 model contains a climate component we are able to extend the analysis made in formative earlier studies [e.g., Archer et al. , 1997Archer et al. , , 1998;;Sundquist, 1990] by now explicitly assessing the impact of major feedbacks between CO 2 and climate on carbonate compensation.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Not checked — no full text of the sourcecites Archer et al., 1997 source
- Supportedcites Archer et al., 1998 source
The citation identifies Archer et al. (1998) as an earlier study of carbonate compensation, not as the study using GENIE-1 or assessing climate–CO2 feedbacks. The Model Description says it simulates the ocean and sediment response to anthropogenic CO2, and §5.3 explicitly describes its treatment of CaCO3 compensation. No page number is available in our copy. (LLM, conf=0.90)
- Not checked — no full text of the sourcecites Sundquist, 1990 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Important feedback may also exist between CO 2 and marine carbonate production.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Supportedcites Orr et al., 2005 source
The introduction (p. 1) says increasing CO2 reduces carbonate availability and calcification. The “Ocean CO2 uptake” section (p. 4) describes the reverse effect: reduced CaCO3 export could increase ocean CO2 uptake and decrease atmospheric CO2. This supports the hedged claim that feedback may exist, although the paper says it would provide little compensation for other reductions in ocean CO2 uptake. (LLM, conf=0.90)
- Not checked — no full text of the sourcecites Caldeira and Wickett, 2003 source
- Supportedcites Zondervan et al., 2001 source
The Discussion (pp. 7–8) models how CO2-related decreases in marine calcification could reverse an expected positive feedback on atmospheric CO2 into a negative one. It also describes the broader ocean–atmosphere response as speculative, consistent with the claim’s ‘may exist’ qualifier. (LLM, conf=0.94)
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Supported
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“With a fixed ocean circulation and climatology it is difficult to account for the importance of feedbacks with climate except in a highly parameterized manner [Archer et al., 2004;Archer, 2005].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Partly supportedcites Archer et al., 2004 sourceExperimental — accuracy not yet measured
Section 4.1.1 describes Hamocc2 as an offline model in which temperature changes affect CO₂ solubility but not ocean circulation; it imposes a uniform temperature response to atmospheric CO₂. The Fig. 3 caption describes that response as “hard wired” into the model. These passages support the claim’s description of parameterized climate feedback under fixed circulation, but do not establish the broader assertion that accounting for such feedbacks is generally difficult except in that manner. (LLM, conf=0.78)
- Not checked — no full text of the sourcecites Archer, 2005 source
plain- Asserted: passes — The authors put it forward as true.
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- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Partly supported
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“most ($70À80%) of the CaCO 3 rain flux reaching the sediment surface dissolves and is returned to the ocean anyway”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 2.3. Ocean-Sediment System Configuration and Spinup
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Excess of carbonate weathering on land over deep-sea burial results in a further net transformation of 14% of CO 2 emissions (261 ppm) into HCO 3 À (''terrestrial CaCO 3 neutralization'') on a timescale of $8.3 ka.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The resulting calibrated model predicts a mean surface sediment content (32.5 wt%) close to the observed value (34.8 wt%)”
- Also stated in: § 4. Present-Day Global Carbonate Cycling · plain
“Global mean surface sediment CaCO 3 content is now 32.5 wt% and much closer to the observational-based estimate of 34.8 wt%”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § 4. Present-Day Global Carbonate Cycling · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“An additional 12% of CO 2 emissions (223 ppm) are sequestered as bicarbonate ions (HCO 3 À ) by reaction with deep-sea carbonates (''seafloor CaCO 3 neutralization'') on a timescale of $1.7 ka.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- It may state two separate claims as one. 24
- Probably not a substantial claim. 5
- The quote only partly states this claim. 2
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“The response of atmospheric CO 2 to ocean-sediment interaction actually comprises contributions from two different mechanisms: (1) the dissolution of carbonates previously deposited to the sediments (seafloor CaCO 3 neutralization) and (2) imbalance between weathering and sedimentation (terrestrial CaCO 3 neutralization) [Archer et al., 1997[Archer et al., , 1998]].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
What the sources say
- Not checked — no full text of the sourcecites Archer et al., 1997 source
- Supportedcites Archer et al., 1998 source
Section 5.3 (CaCO3 Steady State) identifies two complementary neutralization responses: dissolution of previously deposited seafloor CaCO3 and net dissolution of terrestrial CaCO3 when weathering is not balanced by seafloor deposition. This matches the two mechanisms attributed to the paper. (LLM, conf=0.94)
plaindirect- Asserted: passes — The authors put it forward as true.
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- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“This is consistent with a 1500-to 2700-year timescale estimated for a primary alkalinity response in box models [Sundquist, 1990], but about 3 times shorter than the 5À6 ka estimated by Archer et al. [1997Archer et al. [ , 1998]].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
What the sources say
- Not checked — no full text of the sourcecites Sundquist, 1990 source
- Not checked — no full text of the sourcecites Archer et al., 1997 source
- Supportedcites Archer et al., 1998 source
Split into 2 atoms — 2 confirmed, 0 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The sources with a verdict support this claim; the rest weren’t checked yet, have no full text we could read, or their verdicts aren’t rated yet.
In the paper
“Our estimated timescale of 8.3 ka (Figure 7c) is near identical to previous 3-D ocean-based model analyses (8.2À8.5 ka [Archer et al., 1997[Archer et al., , 1998]]) and consistent with the 6300À11,800 year ''secondary alkalinity response'' of Sundquist [1990].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
What the sources say
- Not checked — no full text of the sourcecites Archer et al., 1997 source
- Supportedcites Archer et al., 1998 source
Section 5.2 reports that the modeled relaxation slows to an 8.3 kyr timescale after year 10,000; the Figure 9 caption in Section 5.3 gives the value as 8,260 years. That supports citing this paper for a previous model timescale within 8.2–8.5 ka. The Sundquist response is attributed separately to Sundquist [1990] in the citing sentence. (LLM, conf=0.91)
- Not checked — no full text of the sourcecites Sundquist, 1990 source
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
Every source the paper cites for this claim was checked and supports it.
In the paper
“In the GENIE-1 model, a substantial reduction in CaCO 3 export occurs in response to ocean surface acidification [Ridgwell et al., 2006] (Figure 8c) resulting in a pronounced acceleration of both seafloor and terrestrial CaCO 3 neutralization processes, indicated by the steepening of initial and long-term slopes in Figure 9.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Supportedcites Ridgwell et al., 2006 source
The citation follows the claim that GENIE-1 predicts reduced CaCO3 export in response to acidification. The Results (section 4, p. 5) report that falling calcite saturation led to a 13% decrease in marine carbonate production by 1994. The subsequent claim about accelerated neutralization is presented as the citing paper’s interpretation of its own Figure 9, not as a finding attributed to Ridgwell et al. (LLM, conf=0.91)
plaindirect- Asserted: passes — The authors put it forward as true.
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- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
- Supported
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“Although there are substantial uncertainties in the likely global response of calcifiers to lower surface pH [Kleypas et al., 2006;Ridgwell et al., 2006]”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Not matchedcites Kleypas et al., 2006
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Supportedcites Ridgwell et al., 2006 source
The Conclusions (p. 10) explicitly highlight uncertainties about calcifier responses to anthropogenic ocean acidification and say that experimental responses may not predict ecosystem- or global-level responses. The Discussion (p. 9) also identifies uncertainty in how models represent the calcification response. (LLM, conf=0.94)
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“After a further 10 ka of open system integration we find that the mean sedimentary composition changes by <0.1 wt% CaCO 3 suggesting that configuration as a closed system is not an important source of error.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 2.3. Ocean-Sediment System Configuration and Spinup
hedgedSingle case- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
In the paper
“the global mean carbonate preservation efficiency of 25.8% is consistent with the 20À30% range estimated by Archer [1996].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 2.3. Ocean-Sediment System Configuration and Spinup
What the sources say
- Not checked — no full text of the sourcecites Archer [1996] source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
In the paper
“and a global burial rate of CaCO 3 in deep sea sediments of 0.121 PgC yr À1 , in line with recent budget estimates of 0.10À0.14PgC yr À1 .”
- Also stated in: § 4. Present-Day Global Carbonate Cycling · plain
“Of the CaCO 3 rain to the sediment surface, 0.121 PgC yr À1 is preserved and buried, a value that lies at the centre of recent global carbonate budget estimates of 0.1-0.14PgC yr À1 [Feely et al., 2004].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > Abstract
What the sources say
- Not checked — no full text of the sourcecites Feely et al., 2004 source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
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- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Also stated in: § 4. Present-Day Global Carbonate Cycling · plain
In the paper
“flux (43 Tmol C yr À1 ) falls slightly outside of previous model-based estimates (25À40 Tmol C yr À1 [Archer, 1996])”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 2.3. Ocean-Sediment System Configuration and Spinup
What the sources say
- Not checked — no full text of the sourcecites Archer, 1996 source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“By the start of the next millennium (year 3000), the ocean has achieved near equilibrium with atmospheric composition, with 1418 PgC of fossil fuel CO 2 remaining in the atmosphere, equivalent to 923 ppm above the pre-industrial concentration of 278 ppm.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5. Long-Term Fate of Fossil Fuel CO 2
plain- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Although with the inclusion of the new data constraint, a stable solution to the calibration of 10 parameters was obtained, the two new parameters do not change much from the assumed prior ranges (see auxiliary material).In addition, when adopting these prior ranges, the overall cost was not significantly improved but the global mean and distribution of wt% CaCO 3 in the sediments was degraded.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 3. Data Assimilation and Calibration of Ocean-Sediment Carbon Cycling
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We find that the effects of seafloor and terrestrial carbonate neutralization are approximately equal in magnitude, accounting for the sequestration of 12.4% and 13.7%, respectively, of fossil fuel CO 2 emissions.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We now capture much more of the observed variability in sediment composition (Figure 4d), although the same broad-scale modeldata mismatches remain.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 4. Present-Day Global Carbonate Cycling
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The CaCO 3 rain flux to the sediments of the open ocean (>175 m water depth in the model) is 0.64 PgC yr À1 and is associated with a flux of particulate organic carbon (POC) of 0.87 PgC yr À1 .”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 4. Present-Day Global Carbonate Cycling
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean sedimentary CaCO 3 content of deep-sea sediments (33.3 wt%) and global deep-sea carbonate sink (0.121 PgC yr À1 ) are little changed.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 4. Present-Day Global Carbonate Cycling
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Associated with the warming-driven stratification of the ocean is a restriction in nutrient supply and thus biological (export) production [Plattner et al., 2001;Sarmiento et al., 1998], with a peak year $2200 reduction of about 16% (Figure 8b).”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Not matchedcites Plattner et al., 2001
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not checked — no full text of the sourcecites Sarmiento et al., 1998 source
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Not matched
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Higher atmospheric CO 2 induces a 5.8°C peak warming of annual mean ocean surface temperature and a weakening of Atlantic meridional overturning from 16.3 to 14.1 Sv.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Feedback between CO 2 and calcification is overall negative, enhancing fossil fuel CO 2 sequestration.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Although stratification affects both particulate organic carbon (POC) and CaCO 3 fluxes (Figure 8c) proportionally, the reduction in POC rather than CaCO 3 rain dominates the net effect on the sediments compared to the no-feedbacks case and carbonate preservation is overall enhanced (Figure 8d).”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“A larger difference is observed if the ''PAC_10'' parameter set is used at 36 Â 36 resolution; year CO 2 is 3 ppm lower and declines much quicker with time than under ''PAC_8'', reaching 30 ppm lower by the year 10000.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.3. Sensitivity of Future CO 2 Predictions to Model Configuration
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“The control on atmospheric CO 2 exerted by terrestrial CaCO 3 neutralization is more gradual.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
The quote only partly states this claim.
In the paper
“Feedbacks between climatic changes such as these and CO 2 are overall positive [cf.Friedlingstein et al., 2006], resulting in an enhancement of the concentration of CO 2 in the atmosphere compared to the no-feedback case.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.2. Importance of Climatic and Calcification Feedbacks With CO 2
What the sources say
- Not checked — no full text of the sourcecites Friedlingstein et al., 2006 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“By doing this we find that seafloor CaCO 3 neutralization acts with a faster response time (1.7 ka) than previously estimated, making this process more important to future millennial-scale change than was assumed.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 6. Conclusions
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Increased ocean stratification suppresses particulate organic carbon export, which in turn enhances seafloor CaCO 3 preservation.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“The EnKF method is well converged after each ensemble member has been run for a total of 25,000 years.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 3. Data Assimilation and Calibration of Ocean-Sediment Carbon Cycling
boosted- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“There is also uncertainty as to whether the present-day marine carbonate cycle is at steady state or not [Milliman and Droxler, 1996].”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5. Long-Term Fate of Fossil Fuel CO 2
What the sources say
- Not matchedcites Milliman and Droxler, 1996
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This arises both owing to a larger initial erodable CaCO 3 inventory (38.4 wt%) as well as a greater weathering throughput (0.153 PgC yr À1 ), enhancing seafloor and terrestrial carbonate neutralization mechanisms, respectively.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.3. Sensitivity of Future CO 2 Predictions to Model Configuration
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In contrast, the initial slope of the total CO 2 response reflects both seafloor and terrestrial carbonate neutralization processes operating simultaneously”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one. The quote only partly states this claim.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Differences in model parameterization of bioturbation will affect the rate of exhumation of previously buried carbonates and thus the timescale of CO 2 drawdown.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5.1. Characterizing the Components of Ocean-Sediment Interaction
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: fails — The paper may give no reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“This time interval is necessary for the open system to approach a steady state balance between inputs (weathering) and outputs (sedimentary burial) as well as to accumulate a sufficient depth of calcareous sediments for subsequent CO 2 driven erosion.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5. Long-Term Fate of Fossil Fuel CO 2
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper relies on this without support.
The rate of dissolution of biogenic minerals deposited to marine sediments, particularly CaCO3 and opal, is responsive to changes in the overlying ocean geochemistry.
“This role arises because the rate of dissolution of biogenic minerals deposited to marine sediments, particularly calcium carbonate (CaCO 3 ) and opal (amorphous hydrated silica), is responsive to changes in the overlying ocean geochemistry.”
The paper relies on this without support.
Observed distributions of surface sedimentary properties, particularly CaCO3 and opal, reflect ecological patterns among marine plankton at the ocean surface as well as the depth of the seafloor and geochemistry of the abyssal ocean.
“For instance, observed distributions of surface sedimentary properties, particularly the major solid constituents CaCO 3 and opal, reflect ecological patterns among marine plankton at the ocean surface as well as the depth of the seafloor and geochemistry of the abyssal ocean.”
The authors state this as an assumption.
All organic matter is entirely remineralized in the surface sediments of the deep sea.
“We assume that all organic matter is entirely remineralized in the surface sediments of the deep sea and so omit organic matter as an explicit component of accumulating sediments.”
“It should be noted that particulate organic carbon reaching the sediments is assumed completely remineralized, although CO 2(aq) released by remineralization within the sediments is available for driving carbonate dissolution [Archer, 1991].”
The authors state this as an assumption.
The predicted CO2 trajectory assumes no change in land carbon storage either due to interaction with the terrestrial biosphere or changes in anthropogenic land use.
“The predicted CO 2 trajectory implicitly assumes no change in land carbon storage either due to interaction with the terrestrial biosphere (addressed elsewhere [Lenton et al., 2006]) or changes in anthropogenic land use [e.g., Sitch et al., 2005].”
The authors state this as an assumption.
Year 50,000 is reasonably close to steady state.
“eventual'' (assumed, year 50,000) anthropogenic CO 2 storage”
“assuming that steady state is approximately attained by the year 50,000.”
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 4. Present-Day Global Carbonate Cycling
“The mean sedimentary CaCO 3 content of deep-sea sediments (33.3 wt%) and global deep-sea carbonate sink (0.121 PgC yr À1 ) are little changed.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 6. Conclusions
“| PAC_8 | 33.1 | 0.121 | 1311 | 918 | 569 | 424 | 8-parameter PO 4 + ALK + CaCO 3 assimilation, 72 Â 72 grid |”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 5. Long-Term Fate of Fossil Fuel CO 2
“with 1418 PgC of fossil fuel CO 2 remaining in the atmosphere, equivalent to 923 ppm above the pre-industrial concentration of 278 ppm.”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > Abstract
“with 34% (645 ppm) remaining in the atmosphere out of a total fossil fuel burn of 4173 PgC.”
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 4. Present-Day Global Carbonate Cycling
“Global mean surface sediment CaCO 3 content is now 32.5 wt%”
§ Regulation of atmospheric CO 2 by deep-sea sediments in an Earth system model > 6. Conclusions
“| PAC_8 | 32.4 | 0.121 | 1311 | 914 | 557 | 423 | 8-parameter PO 4 + ALK + CaCO 3 assimilation, 36 Â 36 grid |”
Citations
Cites
Discussion Reporting of 14 C Data
Stuiver, M., & Polach, H. A. (1977) · Radiocarbon · doi:10.1017/s0033822200003672 · Cited by 5,640
Characterizing aquatic dissolved organic matter.
Leenheer, J. A., & Croué, J.-P. (2003) · PubMed · Cited by 4,891
Orr, J. C., Fabry, V. J., Aumont, O., Bopp, L., Doney, S. C., Feely, R. A., Gnanadesikan, A., Gruber, N., Ishida, A., Joos, F., et al. (2005) · Nature · doi:10.1038/nature04095 · Cited by 4,590
Anthropogenic carbon and ocean pH
Caldeira, K., & Wickett, M. E. (2003) · Nature · doi:10.1038/425365a · Cited by 3,549
Climate–Carbon Cycle Feedback Analysis: Results from the C4MIP Model Intercomparison
Friedlingstein, P., Cox, P., Betts, R., Bopp, L., von Bloh, W., Brovkin, V., Cadule, P., Doney, S., Eby, M., Fung, I., et al. (2006) · Journal of Climate · doi:10.1175/jcli3800.1 · Cited by 2,902
Impact of Anthropogenic CO 2 on the CaCO 3 System in the Oceans
Feely, R. A., Sabine, C. L., Lee, K., Berelson, W., Kleypas, J., Fabry, V. J., & Millero, F. J. (2004) · Science · doi:10.1126/science.1097329 · Cited by 2,262
TRENDS '90: A compendium of data on global change
Sepanski, R. J., Boden, T. A., Kanciruk, P., & Farrell, M. P. (1990) · doi:10.2172/6448374 · Cited by 1,586
Armstrong, R. A., Lee, C., Hedges, J. I., Honjo, S., & Wakeham, S. G. (2001) · Deep Sea Research Part II: Topical Studies in Oceanography · doi:10.1016/s0967-0645(01)00101-1 · Cited by 1,064
Simulated response of the ocean carbon cycle to anthropogenic climate warming
Sarmiento, J. L., Hughes, T. M. C., Stouffer, R. J., & Manabe, S. (1998) · Nature · doi:10.1038/30455 · Cited by 899 · cited 1×
“Associated with the warming-driven stratification of the ocean is a restriction in nutrient supply and thus biological (export) production [Plattner et al., 2001; Sarmiento et al., 1998], with a peak year 2200 reduction of about 16% (Figure 8b).”
BackgroundKlaas, C., & Archer, D. E. (2002) · Global Biogeochemical Cycles · doi:10.1029/2001gb001765 · Cited by 821
Research works printed but not linked: 1
- Ridgwell A. J.(2001) Glacial‐interglacial perturbations in the global carbon cycle Ph.D. thesis Univ. of East Anglia at Norwich Norwich U.K.(Available athttp://andy.seao2.org/pubs/ridgwell_2001.pdf).
Cited by
Sorted by citations
The Geological Record of Ocean Acidification
Hönisch, B., Ridgwell, A. J., Schmidt, D. N., Thomas, E., Gibbs, S. J., Sluijs, A., Zeebe, R. E., Kump, L. R., Martindale, R. C., Greene, S. E., et al. (2012) · Science · doi:10.1126/science.1208277 · Cited by 1,065
Self-citationQuantifying the degradation of organic matter in marine sediments: A review and synthesis
Arndt, S., Jørgensen, B. B., LaRowe, D. E., Middelburg, J. J., Pancost, R. D., & Regnier, P. (2013) · Earth-Science Reviews · doi:10.1016/j.earscirev.2013.02.008 · Cited by 1,040
“…in marine sediments are essential for understanding the global carbon cycle and climate (e.g. Arthur et al., 1988; Berner and Canfield, 1989; Berner, 1990; Siegenthaler and Sarmiento, 1993; Archer and Maier-Reimer, 1994; Mackenzie, 2004; Ridgwell and Zeebe, 2005; Ridgwell and Hargreaves, 2007).”
BackgroundMethodAtmospheric Lifetime of Fossil Fuel Carbon Dioxide
Archer, D. E., Eby, M., Brovkin, V. A., Ridgwell, A. J., Cao, L., Mikolajewicz, U., Caldeira, K., Matsumoto, K., Munhoven, G., Montenegro, Á., et al. (2009) · Annual Review of Earth and Planetary Sciences · doi:10.1146/annurev.earth.031208.100206 · Cited by 965
“Other previous studies (Archer et al. 1997, Ridgwell & Hargreaves 2007, Tyrrell et al. 2007) predicted CaCO3 neutralization timescales of millennia and longer, consistent with our results.”
BackgroundMethodResultInfluentialSelf-citationJoos, F., Roth, R., Fuglestvedt, J. S., Peters, G. P., Enting, I. G., von Bloh, W., Brovkin, V., Burke, E. J., Eby, M., Edwards, N. R., et al. (2013) · Atmospheric Chemistry and Physics · doi:10.5194/acp-13-2793-2013 · Cited by 839
Very large release of mostly volcanic carbon during the Palaeocene–Eocene Thermal Maximum
Gutjahr, M., Ridgwell, A. J., Sexton, P. F., Anagnostou, E., Pearson, P. N., Pälike, H., Norris, R. D., Thomas, E., & Foster, G. L. (2017) · Nature · doi:10.1038/nature23646 · Cited by 448
Self-citation
Metadata
- Authors
- Ridgwell, A., & Hargreaves, J. C.
- Affiliations
- University of British Columbia (CA)
- Frontier Research Center for Global Change Yokohama Japan
- Venue
- Global Biogeochemical Cycles
- Publisher
- American Geophysical Union (AGU)
- Published
- 2007-05-04
- Volume
- 21
- Issue
- 2
- ISSN
- 0886-6236 (ISSN-L)
- 1944-9224
- OpenAlex
- W1597746381
- Semantic Scholar
- 1a64d352d5d8dd91b7a6fe37f3761aad2506664f
- Cited by
- 213
- References
- 55
- Citations by year
- 2026: 3 · 2025: 14 · 2024: 12 · 2023: 11 · 2022: 23 · 2021: 26 · 2020: 7 · 2019: 12 · 2018: 8 · 2017: 11 · 2016: 8 · 2015: 9 · 2014: 4 · 2013: 13 · 2012: 9
- FWCI
- 7.99
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Global Biogeochemical Cycles (publishedVersion)
- Explore Bristol Research (submittedVersion)
- Funders
- Canadian Foundation for Climate and Atmospheric Sciences
- Royal Society
- Canada Research Chairs
- Natural Environment Research Council (NE/C515904/1)
- Japan Agency for Marine-Earth Science and Technology
- Topics
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Geology and Paleoclimatology Research
- Physical Sciences › Earth and Planetary Sciences › Oceanography › Marine Plankton and Biogeochemistry
- Physical Sciences › Environmental Science › Global and Planetary Change › Climate variability and models
- Keywords
- deep-sea sediments, ocean carbon cycle, ocean stratification, particulate organic carbon export, carbon cycle feedbacks, ensemble Kalman filter, sedimentary stratigraphy
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-10-11, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-10-11 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Cited sources are checked with a language model’s help (gpt-6-sol).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
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