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Cited by 216Paleontology and Stratigraphy of FossilsGeology and Paleoclimatology ResearchEarth Systems and Cosmic Evolution

Evolution of the Global Carbon Cycle and Climate Regulation on Earth

Open access
Isson, T. T., Planavsky, N. J., Coogan, L. A., Stewart, E. M., Ague, J. J., Bolton, E. W., Zhang, S., McKenzie, N. R. +1 more·2020·Global Biogeochemical Cycles
DOI 10.1029/2018gb006061
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Abstract

The existence of stabilizing feedbacks within Earth's climate system is generally thought to be necessary for the persistence of liquid water and life. Over the course of Earth's history, Earth's atmospheric composition appears to have adjusted to the gradual increase in solar luminosity, resulting in persistently habitable surface temperatures. With limited exceptions, the Earth system has been observed to recover rapidly from pulsed climatic perturbations. Carbon dioxide (CO 2) regulation via negative feedbacks within the coupled global carbon‐silica cycles are classically viewed as the main processes giving rise to climate stability on Earth. Here we review the long‐term global carbon cycle budget, and how the processes modulating Earth's climate system have evolved over time. Specifically, we focus on the relative roles that shifts in carbon sources and sinks have played in driving long‐term changes in atmospheric pCO 2. We make the case that marine processes are an important component of the canonical silicate weathering feedback, and have played a much more important role in p CO 2 regulation than traditionally imagined. Notably, geochemical evidence indicate that the weathering of marine sediments and off‐axis basalt alteration act as major carbon sinks. However, this sink was potentially dampened during Earth's early history when oceans had higher levels of dissolved silicon (Si), iron (Fe), and magnesium (Mg), and instead likely fostered more extensive carbon recycling within the ocean‐atmosphere system via reverse weathering—that in turn acted to elevate ocean‐atmosphere CO 2 levels.

Integrity signals

Registry

Crossref · 10.1029/2018gb006061

Cites

227 of 227 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 132 cited sources checked · 0 supported · 0 flagged

  • Findingreasoning

    Silicate weathering rates decline as a soil horizon matures because primary mineral phases become more depleted.

    “Silicate weathering rates decrease as a soil horizon matures given that primary phases become more depleted (Fig. 9).”
    Quote in the paperSubstantial claim
  • Findingcitation

    Flux estimates from different submarine groundwater discharge approaches are typically significantly different.

    “Unfortunately, flux estimates from these approaches are typically significantly different (see discussion in Zhang and Planavsky, 2019)”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Zhang and Planavsky, 2019

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  • Findingcitation

    The sedimentary record of zircon production from the Cryogenian to the present, about the past 720 million years, correlates with icehouse-greenhouse transitions.

    “The sedimentary record of zircon production was assessed in sediments ranging from the Cryogenian to the present (i.e., the past ~720 million years of Earth history) and demonstrated a correlation with icehousegreenhouse transitions.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites McKenzie et al., 2016

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  • Findingown data

    At 280 ppm pCO2, the water-rock mass balance model requires 10 m/yr of rainfall to neutralize volcanic CO2 if soil respiration is absent.

    “The model outputs indicate that at pCO 2 levels of 280 ppm, 10m yr -1 of rainfall is required to neutralize volcanic CO 2 if here was no soil respiration.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Rainwater is quantitatively neutralized by weathering in the water-rock mass balance model.
    • The authors state this as an assumption: All infiltrating carbon dioxide is neutralized in the water-rock mass balance model.
  • Findingown data

    The required rainfall at 280 ppm pCO2 is about an order of magnitude greater than modern average annual rainfall.

    “This is roughly an order of magnitude higher than modern average annual rainfall estimates.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Rainwater is quantitatively neutralized by weathering in the water-rock mass balance model.
    • The authors state this as an assumption: All infiltrating carbon dioxide is neutralized in the water-rock mass balance model.
  • May combine two claims. 46
  • Classified as probably not a substantial claim. 27

  • May combine two claims.

    Findingnone given

    There is no evidence for a step increase in surface temperatures associated with the emergence of deep-sea carbon burial; the Cretaceous is anomalously warm, but the Cenozoic is anomalously cool.

    “Interestingly, however, there is no evidence for a step increase in surface temperatures associated with the emergence of deep-sea carbon burial; although the Cretaceous is an anomalously warm period, the Cenozoic is an anomalously cool period.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingreasoning

    Under high pCO2 conditions, rainfall becomes the dominant CO2 source and soil respiration changes play a smaller role.

    “Under these conditions, rainfall becomes the dominant source of CO 2 , and changes in soil respiration will play a smaller role.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: Rainwater is quantitatively neutralized by weathering in the water-rock mass balance model.
    • The authors state this as an assumption: All infiltrating carbon dioxide is neutralized in the water-rock mass balance model.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Several studies argue that submarine groundwater discharge fluxes of dissolved inorganic carbon and alkalinity exceed regional river input and in some cases are an order of magnitude larger.

    “For dissolved inorganic carbon (DIC) and alkalinity, several studies argued that SGD-derived fluxes exceed regional river input and in some cases are one order of magnitude larger (Liu et al., 2014;Stewart et al., 2015).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Liu et al., 2014

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    • cites Stewart et al., 2015

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Cho et al. (2018) reported that dissolved inorganic nitrogen, phosphorus, and silicon derived from submarine groundwater discharge are comparable with river fluxes to the global ocean.

    “In terms of element fluxes, it is reported by Cho et al. (2018) that dissolved inorganic nitrogen, phosphorus, and silicon derived from SGD are comparable with the river fluxes to the global ocean.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Cho et al., 2018

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  • May combine two claims.

    Premisecitation

    Bryophytes such as liverworts, which evolved earlier in the Ordovician, have been shown to accelerate weathering rates, and comparing their effect with that of vascular plants with deeper roots is difficult.

    “First, the earlier evolving bryophytes (liverworts; in the Ordovician) (Quirk et al., 2015) have also been shown to accelerate weathering rates, and direct comparison of these with the effect of vascular plants (with more deeply penetrating roots) has proven challenging.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Quirk et al., 2015

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    It has been proposed that roughly one third of the alkalinity from CO2 neutralized by silicate dissolution in marine sediments precipitates as authigenic carbonate, with the rest fluxing into overlying seawater.

    “it has been proposed that roughly a third of this alkalinity is precipitated in marine sediments as authigenic carbonate, and the rest fluxed into overlying seawater (Wallmann and Aloisi, 2012;Wallmann et al., 2008).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Wallmann and Aloisi, 2012

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    • cites Wallmann et al., 2008

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    • The authors state this as an assumption: All CO2 produced by methanogenesis in marine sediments is neutralized by silicate mineral dissolution.

  • May combine two claims.

    Interpretationnone given

    Seepage meters lack global coverage, and up-scaling seepage measurements remains a challenge.

    “The installation of seepage meters lacks global coverage, and up-scaling of seepage measurement remains a challenge.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisenone given

    Silicate weathering rates have been observed to change with depth in the sediment pile and laterally between depositional environments.

    “Further, silicate weathering rates have been observed to evolve with depth into the sediment pile and laterally between depositional environments.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Groundwater has on average significantly higher bicarbonate concentrations than overlying surface waters, indicating that weathering occurs deeper within the crust as well as in soil horizons.

    “Groundwater contains, on average, significantly higher bicarbonate concentrations than overlying surface waters, indicating that weathering occurs not only in soil horizons but also deeper within the crust (Zhang and Planavsky, in press).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Zhang and Planavsky, in press

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  • May combine two claims.

    Premisenone given

    Seawater and porewaters are generally undersaturated with respect to primary silicate minerals, so their dissolution helps buffer pore fluid pH and chemistry.

    “This is perhaps unsurprising as seawater and porewaters are generally undersaturated with respect to primary silicate minerals, and thus their dissolution plays a role in buffering pore fluid pH and chemistry.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Combining global 228Ra observations and an inverse model, Kwon et al. (2014) argued that submarine groundwater discharge along coastlines between 60°S and 70°N is about three times greater than river discharge.

    “Combining global observations of 228 Ra and an inverse model, (Kwon et al., 2014) argued that the SGD along the coastlines between 60°S and 70°N is around 3 times greater than the river discharge.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kwon et al., 2014

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  • May combine two claims.

    Premisenone given

    The rate of silicate dissolution is ultimately determined by the availability of primary silicate minerals and by porewater chemistry.

    “Both the availability of primary silicate minerals and porewater chemistry ultimately determine the rate of silicate dissolution.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Using 228Ra as a tracer, Moore et al. (2008) concluded that submarine groundwater discharge in the Atlantic coastal region is comparable to the corresponding river flux.

    “Using 228 Ra as a tracer, (Moore et al., 2008) concluded that the magnitude of SGD in coastal region of the Atlantic Ocean is comparable to the corresponding river flux.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Moore et al., 2008

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  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Iron oxidation likely accounts for a smaller portion of the acid that facilitates weathering, though this flux is poorly constrained.

    “Iron oxidation likely accounts for a smaller portion of the acid that facilitates weathering, although this flux is poorly constrained.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisenone given

    The uppermost layer of oceanic crust consists of high-porosity, high-permeability lavas through which seawater continually circulates.

    “The uppermost layer of this crust is made up of high-porosity and permeability lavas through which seawater continually circulates.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisenone given

    Porewater chemistry evolves with depth, especially between redox zones tied to organic matter oxidation, and can alter the saturation state and dissolution rate of silicate phases.

    “Critically, porewater chemistry evolves with depth, most notably between redox zones tied to the oxidation of organic matter, and has the potential to alter the saturation state (and thus dissolution rate) of silicate phases.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Interpretationnone given

    Recent studies suggest that silicate mineral dissolution in marine environments contributes to global alkalinity and carbon sequestration, so the terrestrial-to-marine transition is better viewed as a continuum rather than two distinct environments.

    “The emerging perspective from recent studies is that silicate mineral dissolution within marine environments contributes to global alkalinity and thus carbon sequestration, suggesting that the terrestrial to marine transition is better viewed as a continuum rather than two distinct environments.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Large uncertainties exist in estimating fresh submarine groundwater discharge and the extent of groundwater-mediated silicate weathering.

    “This estimate highlights foremost that large uncertainties exist for estimating fresh SGD and the extent of groundwater mediated silicate weathering.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    After correcting for salinity, Cho and Kim (2016) stated that global submarine groundwater discharge is approximately 1 to 1.5 times river discharge, not 3 to 4 times.

    “After correcting the salinity effect, (Cho and Kim, 2016) stated that instead of 3 to 4 times, global SGD is approximately 1-1.5 times the river discharge.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Cho and Kim, 2016

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  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Premisenone given

    Oceanic crust continually accreted along the global mid-ocean ridge network covers more than half of Earth's surface.

    “Oceanic crust that is continually accreted along the global mid-ocean ridge network covers more than half of Earth's surface.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Sulfuric acid from pyrite oxidation accounts for about 5% of silicate dissolution and 10% of carbonate dissolution in terrestrial weathering.

    “Sulfuric acid (H 2 SO 4 ) derived from the oxidation of pyrite: FeS 2 + 3.75 O 2 + 3.5 H 2 O ↔ 2 H 2 SO 4 + Fe(OH) 3 (4) also accounts for a portion of the acid that facilitates weathering in the terrestrial environment (~ 5% of silicate dissolution and 10% of carbonate dissolution) (Brantley, 2008;Torres et al., 2014).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Brantley, 2008 source

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    • cites Torres et al., 2014

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  • May combine two claims.

    Interpretationcitation

    Fresh submarine groundwater discharge might be significantly less than river discharge, and its element flux including dissolved carbon might be diminished.

    “Consequently, fresh SGD might be significantly less than river discharge (Taniguchi, 2002), and the element flux (including dissolved carbon) derived from fresh SGD might be diminished.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Taniguchi, 2002

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  • May combine two claims.

    Premisecitation

    Staudigel et al. (1989) found that lavas in three western Atlantic drill cores had taken up substantial seawater carbon, about 2.9 weight percent CO2, equivalent to about 2.9 times 10^12 mol per year if globally representative.

    “Staudigel et al. (1989) presented the first detailed study of C-uptake during seafloor weathering focusing on three closely spaced drill cores from the western Atlantic showing that the lavas in these holes had taken up substantial seawater C in the lava section (~2.9 wt% CO 2 , equivalent to ~2.9x10 12 mol yr -1 if these were globally representative).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Staudigel et al., 1989

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  • May combine two claims.

    Premisecitation

    O-isotope thermometry shows that both the minimum and average temperature of carbonate precipitation in the upper oceanic crust track bottom water temperature, being higher in the late Mesozoic than in the late Cenozoic.

    “Additionally, O-isotope thermometry shows that both the minimum and average temperature of precipitation of carbonate in the upper oceanic crust track bottom water temperature, being higher in the late Mesozoic than late Cenozoic (Coogan and Gillis, 2018;Gillis and Coogan, 2011).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Coogan and Gillis, 2018

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    • cites Gillis and Coogan, 2011

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  • May combine two claims.

    Premisecitation

    Observations from many ocean crust drill cores show that total CO2 uptake by the lava section of oceanic crust through time is variable and was significantly higher for late Mesozoic crust than for late Cenozoic crust.

    “Nonetheless, observations from a larger number of ocean crust drill cores have now shown that the total CO 2 uptake by the lava section of the oceanic crust through time is variable and was significantly higher for crust formed in the late Mesozoic than late Cenozoic (Alt and Teagle, 1999;Gillis and Coogan, 2011).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Alt and Teagle, 1999

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    • cites Gillis and Coogan, 2011

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  • May combine two claims.

    Premisecitation

    Zircon is an accessory mineral commonly produced in silicic magmas, which are produced in large volumes along continental arc systems.

    “Zircon is an accessory mineral commonly produced in silicic magmas (e.g., Lee and Bachmann, 2014), which are produced in large volumes along continental arc systems.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Lee and Bachmann, 2014

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The total amount of new silicon introduced into the ocean system is estimated at about 10.9 Tmol per year.

    “For reference, the total amount of new Si introduced into the ocean system is estimated at ~10.9 Tmol yr -1 (Tréguer and De La Rocha, 2013).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Tréguer and De La Rocha, 2013

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  • May combine two claims.

    Interpretationreasoning

    Outgassing history likely includes unidirectional changes tied to Earth's long-term thermal and tectonic evolution, with superimposed shorter-term cyclic changes on the order of several million years linked to tectonic processes.

    “There are likely unidirectional changes in the history of outgassing, tied to Earth's long-term thermal and tectonic evolution and, superimposed on this shorter-term cyclic changes on the order of several million years linked to tectonic processes.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationcitation

    The rapid spreading rate model clashes with empirical observations and first-principle geophysical modeling, which provide strong evidence that the early Earth had slow ocean ridge spreading rates.

    “But this rapid spreading rate model clashes strongly with empirical observations and first principle geophysical modeling, which provide strong evidence that the early Earth was instead characterized by slow rates of ocean ridge spreading (Korenaga, 2018).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Korenaga, 2018

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  • May combine two claims.

    Interpretationreasoning

    All else equal, the upper portion of an anoxic marine sediment pile above the sulfate-methane transition zone should favor reverse weathering, while below it should favor marine weathering.

    “Thus all else being equal, the chemistry of the upper portion of an anoxic marine sediment pile above the sulfate-methane transition zone would be expected to produce conditions that favor reverse weathering type reactions (increase saturation state of silicate minerals), and favor marine weathering below it (Section 3.2.5).”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisenone given

    Alkalinity-to-silica ratios of standard clay compositions span a large range from kaolinite up to 4.0.

    “Alk:Si ratios of standard clay compositions (note that many have flexible stoichiometries) span a large range between kaolinite and up to 4.0.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Sediment near an arc is generally dominated by relatively young arc-derived zircons, whereas sediment farther away contains mixed zircons from older bedrock sources with reduced abundance of young grains.

    “Sediment collected in close proximity to the arc will generally be dominated by relatively young arc-derived zircons, whereas zircon collected further away from the arc will likely contain mixed zircons from older bedrock sources and with the abundance of the young grains being reduced (Blum and Pecha, 2014;Capaldi et al., 2017).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Blum and Pecha, 2014

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    • cites Capaldi et al., 2017

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  • May combine two claims.

    Premisenone given

    Oxidation of organic matter via aerobic respiration and methanogenesis generates acidity, while iron and sulfate reduction consumes acidity.

    “Specifically, the oxidation of organic matter tied to aerobic respiration and methanogenesis generates acidity while iron and sulfate reduction consumes acidity.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisereasoning

    Kaolinite formation does not consume soluble cations or alkalinity and therefore has no impact on the global carbon cycle.

    “The formation of kaolinite, for instance, does not consume soluble cations and thus alkalinity, and so has no impact on the global carbon cycle.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationcitation

    Most upper oceanic crust carbonate precipitates within the first 20 million years after crustal accretion, suggesting that the Mesozoic-Cenozoic CO2 content difference reflects differences in ocean temperature and composition.

    “Further, most upper oceanic crust carbonate is precipitated within the first 20 Myr after crustal accretion (Coogan and Dosso, 2015;Coogan et al., 2016;Staudigel and Hart, 1985), suggesting that this difference in CO 2 content reflects something intrinsically different about the system between these times-the most likely candidates being differences in ocean temperature and composition.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Coogan and Dosso, 2015

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    • cites Coogan et al., 2016

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    • cites Staudigel and Hart, 1985

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  • May combine two claims.

    Premisecitation

    A sandstone may contain zircons with crystallization ages billions of years older than the rock's depositional age; even modern river sands can yield Archean-aged zircon.

    “This is why a sandstone may contain a wide variety of zircons with crystallization ages billions of years older than the depositional age of the rock-even modern river sands can yield Archean aged zircon (Campbell and Allen, 2008).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Campbell and Allen, 2008

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  • May combine two claims.

    Interpretationcitation

    The marine environment changed dramatically with the advent of deep sea carbon burial in the Mesozoic, and this shift in the carbonate factory could have changed CO2 outgassing.

    “The marine environment has changed dramatically with the advent of a deep sea carbon burial in the Mesozoic (Ridgwell, 2005), and this shift in the carbonate factory could have changed CO 2 outgassing.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Ridgwell, 2005

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  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisenone given

    Mafic rocks can contain zircons but are far less abundant than higher-silica rocks.

    “Mafic rocks can certainly contain zircons; however, they are far less abundant than in the higher silicic content rocks.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisenone given

    Sepiolite has an alkalinity-to-silica ratio of 1.33, greenalite 3.0, and berthierine 4.0.

    “For instance, sepiolite has an Alk:Si= 1.33, greenalite = 3.0, berthierine = 4.0.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    A significant temperature dependence of seafloor basalt alteration was proposed from basalt-seawater experiments and is supported by Sr-isotope modeling and global carbon-cycle models.

    “A significant temperature dependence of seafloor basalt alteration was proposed by Brady and Gíslason (1997) based on basalt-seawater experiments and is supported by modeling Sr-isotope systematics in these systems (Coogan and Dosso, 2015) and by global C-cycle models (Krissansen-Totton and Catling, 2017).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Brady and Gíslason, 1997

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    • cites Coogan and Dosso, 2015

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    • cites Krissansen-Totton and Catling, 2017

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  • May combine two claims.

    Interpretationreasoning

    Thus, the temperature of seawater-basalt reactions in the upper oceanic crust increases, leading to elevated CO2 consumption and a stabilizing feedback on the carbon cycle.

    “Thus, the temperature of seawater-basalt reactions in the upper oceanic crust increases leading to elevated CO 2 consumption (alkalinity generation) and a stabilizing feedback on the C-cycle.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Premisenone given

    Kinetic data for basalt alteration and marine porewater conditions are much less abundant than for terrestrial soils.

    “The amount of kinetic data for conditions relevant to basalt alteration and marine porewaters is well short of that for terrestrial soils.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisenone given

    Ferric iron reduction and sulfate reduction produce alkalinity.

    “Sulfide and ferrous iron oxidation produce acidity while ferric iron and sulfate reduction produce alkalinity-potentially altering the ocean-atmosphere carbonic acid system balance and thus the ocean's capacity to hold inorganic carbon.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Recent studies have used global detrital zircon U-Pb data to track the spatial distribution of arc systems at various time scales.

    “Recent studies have utilized global detrital zircon U-Pb data to track the spatial distribution of arc systems at various time scales (McKenzie et al., 2016;McKenzie et al., 2014).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites McKenzie et al., 2016

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    • cites McKenzie et al., 2014

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  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Diffuse fluxes are more difficult to constrain than point sources.

    “This should not be a surprise since diffuse fluxes are of course more difficult to constrain than point sources.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Marine authigenic clay mineral assemblages likely changed over time.

    “Marine authigenic clay mineral assemblages are likely to have evolved through time.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Bachan and Kump proposed that siderite oxidation was likely important during the Archean-Paleoproterozoic transition.

    “Bachan and Kump (2015) proposed that this process was likely important during the Archean-Paleoproterozoic transition, which saw Earth's first notable rise in atmospheric oxygen levels.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Bachan and Kump (2015)

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  • Classified as probably not a substantial claim.

    Interpretationcitation

    Enhanced carbon recycling in the early Precambrian could have sustained a significantly elevated pCO2 baseline.

    “In this view, enhanced carbon recycling during this time could have sustained a significantly elevated pCO 2 baseline, providing a solution to the faint young Sun paradox that does not necessitate invoking a significant reduction to the weatherability of Earth's surface.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Isson and Planavsky, 2018

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  • May combine two claims.

    Premisereasoning

    Extensive continental arc systems existed during the Ediacaran and early Paleozoic to form Gondwana, during the mid-Paleozoic to form Pangea, and during the Mesozoic to early Cenozoic following Pangea breakup.

    “Extensive continental arc systems existed throughout the Ediacaran and early Paleozoic to form Gondwana, during the mid-Paleozoic to form Pangea, and the Mesozoic to early Cenozoic following the breakup of Pangea.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The exoplanet habitable zone is typically defined by assuming a planet's maximum greenhouse gas capacity.

    “The 'habitable zone' for exoplanets-where liquid water can exist-is typically delineated by assuming the maximum greenhouse gas capacity of a planet (Kasting et al., 1993).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kasting et al., 1993

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    An elevated early Precambrian pCO2 baseline could solve the faint young Sun paradox without requiring a large decrease in Earth's surface weatherability.

    “In this view, enhanced carbon recycling during this time could have sustained a significantly elevated pCO 2 baseline, providing a solution to the faint young Sun paradox that does not necessitate invoking a significant reduction to the weatherability of Earth's surface.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Marine weathering and reverse weathering are likely more important controls on long-term climate than traditionally thought.

    “We make a case that marine processes (marine weathering and reverse weathering) are likely more important controls on long-term climate than traditionally envisioned (e.g., in contrast to Berner, 2004).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Berner, 2004

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  • May combine two claims.

    Premisenone given

    Major uncertainties exist in the processes controlling terrestrial silicate weathering rates and in the balance between terrestrial and marine silicate weathering.

    “However, there are major uncertainties in the processes controlling terrestrial silicate weathering rates and in the balance between terrestrial and marine silicate weathering.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Authigenic clays form a significant portion of the mineralogical and textural composition of marine sediments.

    “While authigenic clays have long been recognized to make up a significant portion of the mineralogical and textural makeup of marine sediments (e.g., Hazen et al., 2013), a wide variety of species have been reported”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Hazen et al., 2013

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    Intervals of extensive continental arcs correspond with greenhouse climates, whereas the final collisions forming Gondwana, Pangea, and the closure of Tethys correspond with icehouses.

    “These intervals correspond with greenhouse climates, whereas the final collisions that formed Gondwana, Pangea, and the closure of the Tethys ocean (Cawood and Buchan, 2007;Lee et al., 2013) all correspond with icehouses (McKenzie et al., 2016;McKenzie et al., 2014).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Cawood and Buchan, 2007

      Not checked in the free run.

    • cites Lee et al., 2013

      Not checked in the free run.

    • cites McKenzie et al., 2016

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Reverse weathering rates were likely elevated in early Precambrian oceans, linked to higher dissolved Si, Fe, and Mg levels characteristic of that time.

    “In particular, it was recently proposed that reverse weathering rates were likely elevated in early Precambrian oceans, directly linked to the higher dissolved Si, Fe and Mg levels that are traditionally viewed to be characteristic features of this time period (Isson and Planavsky, 2018).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Isson and Planavsky, 2018

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    As plates break up and migrate, volcanic arc systems become more prevalent, whereas continental collision shuts down and reduces arc systems.

    “Therefore, as plates break up and migrate around, volcanic arc systems will be more prevalent, whereas the collision of continental blocks shuts down and reduces arc systems.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    There is abundant evidence for deposition of Fe silicates and Fe oxides in the Archean.

    “Although there is strong evidence that the crust contained abundant Fe carbonates in the Archean-there is also abundant evidence for the deposition of Fe silicates (e.g., Johnson et al., 2018;Rasmussen et al., 2017) and Fe oxides (e.g., Bekker et al., 2014).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Johnson et al., 2018

      Not checked in the free run.

    • cites Rasmussen et al., 2017

      Not checked in the free run.

    • cites Bekker et al., 2014

      Not checked in the free run.

  • May combine two claims.

    Interpretationcitation

    The correlation suggests a causative link between arc activity and climate transitions: reduced volcanism leads to icehouse states, while expanded volcanic arcs lead to greenhouse climates.

    “This suggests a causative link between arc activity and climate transitions-when volcanism was reduced Earth moved into an icehouse state, whereas when volcanic arcs expanded, Earth moved into a greenhouse climate (McKenzie et al., 2016).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites McKenzie et al., 2016

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The Archean-Paleoproterozoic transition included Earth's first notable rise in atmospheric oxygen.

    “Bachan and Kump (2015) proposed that this process was likely important during the Archean-Paleoproterozoic transition, which saw Earth's first notable rise in atmospheric oxygen levels.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    A well-grounded general theory of carbon cycling on terrestrial planets is essential for predicting how likely a habitable-zone planet is to sustain life.

    “Therefore, a well-grounded general theory of carbon cycling on terrestrial planets is essential to predict how likely a planet within the habitable zone will sustain the evolution and persistence of life.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisenone given

    Sulfide oxidation and ferrous iron oxidation produce acidity.

    “Sulfide and ferrous iron oxidation produce acidity while ferric iron and sulfate reduction produce alkalinity-potentially altering the ocean-atmosphere carbonic acid system balance and thus the ocean's capacity to hold inorganic carbon.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The radiation of siliceous organisms forced a decrease in the extent of reverse weathering and in baseline pCO2 levels.

    “The subsequent radiation of siliceous organisms (sponges, radiolarians, and most recently diatoms) through the Phanerozoic forced a drop in dissolved marine Si levels, and thus the extent of reverse weathering and baseline pCO 2 levels.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisenone given

    Continental break-up requires rift systems and new ocean basins, which in turn require subduction zones to accommodate oceanic spreading.

    “Continental break-up requires the establishment of rift systems and the opening of new ocean basins, which also requires the establishment of subduction zones to accommodate oceanic spreading.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

    Premisenone given

    The debate is often reduced to whether carbon sources or carbon sinks drove climate shifts.

    “This debate is often distilled down into arguments about whether the sources or sinks of carbon sources have driven climate shifts.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Higher dissolved silica and iron levels in the Precambrian ocean favored enhanced reverse weathering and dampened marine weathering.

    “Higher dissolved silica and iron levels that are hallmark features of the Precambrian ocean gave rise to conditions that favored enhanced rates of reverse weathering, and dampened marine weathering rates (Isson and Planavsky, 2018).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Isson and Planavsky, 2018

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    The drop in dissolved marine silica concentrations would have lowered the saturation state of clay minerals, causing less reverse weathering and more marine weathering.

    “This drop in dissolved marine Si concentrations would have decreased the saturation state of clay minerals-leading to less reverse weathering and more marine weathering.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Because the modern carbon cycle mass balance is still debated, it is unsurprising that no clear consensus exists on the factors driving long-term climate shifts.

    “Given that there is still debate about the modern carbon cycle mass balance, it is unsurprising that there is not a clear consensus about the factors that have driven long term shifts in Earth's climate.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationnone given

    Reverse weathering stabilizes the climate system, and its rates depend on pH.

    “Reverse weathering, the rates of which are pH dependent, also stabilizes the climate system.”
    Quote in the paperSubstantial claim
69 of 69

  • The authors state this as an assumption.

    All CO2 produced by methanogenesis in marine sediments is neutralized by silicate mineral dissolution.

    “and the assumption that all this CO 2 is neutralized through silicate mineral dissolution in marine sediments (Wallmann et al., 2008)”

  • The authors state this as an assumption.

    Careful assessment of detrital zircon age data can provide first-order insights into global continental magmatism and CO2 outgassing through time.

    “it is reasonable to assume that careful assessment of detrital zircon age-data may provide first order insights into global continental magmatism and CO 2 outgassing through time.”

  • The paper relies on this without support.

    The oceans remained anoxic through most of the Precambrian and possibly into the early Phanerozoic.

    “Further, the oceans appear to have remained anoxic through most of the Precambrian and potentially even in the early Phanerozoic.”

  • The paper relies on this without support.

    The Archean continental crust contained abundant iron carbonates.

    “Although there is strong evidence that the crust contained abundant Fe carbonates in the Archean-there is also abundant evidence for the deposition of Fe silicates (e.g., Johnson et al., 2018;Rasmussen et al., 2017) and Fe oxides (e.g., Bekker et al., 2014).”

  • The authors state this as an assumption.

    Rainwater is quantitatively neutralized by weathering in the water-rock mass balance model.

    “This model assumes quantitative neutralization of rainwater through weathering.”

  • The authors state this as an assumption.

    All infiltrating carbon dioxide is neutralized in the water-rock mass balance model.

    “New CO 2 input into the system is set at 10 Tmol yr -1 and all infiltrating CO 2 is assumed to be neutralized.”
6 of 6

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.

  • Arc-volcanism upper estimate differs between text and budget table

    Minor

    The text gives 3.2 Tmol CO2 per year as the upper end of the modern arc-volcanic degassing range, while the budget table gives 3.5 for the same flux.

1 of 1

Cites

Flagged first, then by citations

Research works printed but not linked: 6

  1. Algeo T. J., 1995, Late Devonian oceanic anoxic events and biotic crises:“rooted” in the evolution of vascular land plants, GSA Today, 5, 45
  2. Dole S., 1964, Habitable planets for man
  3. Högbom A., 1894, On the probability of secular variations of atmospheric carbon dioxide (in Swedish), Svensk Kemisk Tidskrift, 6, 169
  4. Hoyle F., 1957, The black cloud, 26
  5. Krissansen‐Totton J., 2017, Constraining climate sensitivity and continental versus seafioor weathering using an inverse geological carbon cycle model, Nature, 8, 1
  6. Ronov A., 1990, Chemical composition of the Earth's crust and geochemical balance of main elements

Cited by

Sorted by citations

Related

Authors
Isson, T. T., Planavsky, N. J., Coogan, L. A., Stewart, E. M., Ague, J. J., Bolton, E. W., Zhang, S., McKenzie, N. R., & Kump, L. R.
Affiliations
  • Yale University (US)
  • University of Victoria (CA)
  • University of Hong Kong (HK)
  • Pennsylvania State University (US)
Corresponding author
  • Isson, T. T.
  • Planavsky, N. J.
ORCID
Venue
Global Biogeochemical Cycles
Publisher
American Geophysical Union (AGU)
Published
2020-01-31
Volume
34
Issue
2
ISSN
  • 0886-6236 (ISSN-L)
  • 1944-9224
DOI
10.1029/2018gb006061
OpenAlex
W2998006343
Cited by
216
References
227
Citations by year
2026: 32 · 2025: 42 · 2024: 40 · 2023: 44 · 2022: 23 · 2021: 27 · 2020: 8
FWCI
11.05
Type
journal article
Language
en
Open access
Licence
onlinelibrary.wiley.com/termsAndConditions#vor (vor)
Locations
  • Global Biogeochemical Cycles (publishedVersion)
  • Research Commons (University of Waikato) (submittedVersion)
Funders
  • National Science Foundation (EAR‐1650329)
  • Heising-Simons Foundation
  • NASA Astrobiology Institute
  • National Aeronautics and Space Administration
Topics
  • Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
  • Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Geology and Paleoclimatology Research
  • Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Earth Systems and Cosmic Evolution
Keywords
carbon cycle, climate regulation, atmospheric pCO2, silicate weathering, basalt alteration, reverse weathering, carbon sink, carbon source, climate stability, early Earth, air-sea CO2 flux, dissolved silica, Earth system evolution

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.

Claims read under definition version 3 (extract-v3) on 2026-09-28.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-09-28.

Statistics and arithmetic are recomputed, not judged.

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