Low-latitude glaciation in the Palaeoproterozoic era

Evans, David A.D.; Beukes, N. J.; Kirschvink, Joseph L.

doi:10.1038/386262a0

Cited by 311 publications

(170 citation statements)

References 19 publications

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“…Bekker et al (2001) suggest that the Rooihoogte and Timeball Hill formations in South Africa coincide with the second and third of the Huronian glaciations. Some glaciations in Canada and South Africa, however, may not necessarily correlate at all: only one glaciation (the Makganyene) in South Africa has been demonstrated to be global (Evans et al 1997), whereas reliable palaeolatitude data are missing from the Huronian . Thus, Kopp et al (2005) argue that all three Huronian glaciations precede the 'snowball' Makganyene glaciation in South Africa.…”

Section: Triggering Of the Palaeoproterozoic Glaciationsmentioning

confidence: 99%

Palaeoclimates: the first two billion years

Kasting

Ono

2006

Phil. Trans. R. Soc. B

124

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Earth's climate during the Archaean remains highly uncertain, as the relevant geologic evidence is sparse and occasionally contradictory. Oxygen isotopes in cherts suggest that between 3.5 and 3.2 Gyr ago (Ga) the Archaean climate was hot (55-85 8C); however, the fact that these cherts have experienced only a modest amount of weathering suggests that the climate was temperate, as today. The presence of diamictites in the Pongola Supergroup and the Witwatersrand Basin of South Africa suggests that by 2.9 Ga the climate was glacial. The Late Archaean was relatively warm; then glaciation (possibly of global extent) reappeared in the Early Palaeoproterozoic, around 2.3-2.4 Ga.Fitting these climatic constraints with a model requires high concentrations of atmospheric CO 2 or CH 4 , or both. Solar luminosity was 20-25% lower than today, so elevated greenhouse gas concentrations were needed just to keep the mean surface temperature above freezing. A rise in O 2 at approximately 2.4 Ga, and a concomitant decrease in CH 4 , provides a natural explanation for the Palaeoproterozoic glaciations. The Mid-Archaean glaciations may have been caused by a drawdown in H 2 and CH 4 caused by the origin of bacterial sulphate reduction. More work is needed to test this latter hypothesis.

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Section: Triggering Of the Palaeoproterozoic Glaciationsmentioning

confidence: 99%

Palaeoclimates: the first two billion years

Kasting

Ono

2006

Phil. Trans. R. Soc. B

124

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“…Evans et al 1997;Hoffman et al 1998) that are to the left of the MEP state in figure 1 could only be reached in transient states. Since radiative gradients would not be at their maximum value, the strength of the atmospheric circulation would be weaker than at the MEP state, allowing for less hydrologic and geochemical cycling.…”

Section: Application To Earth-system Evolutionmentioning

confidence: 99%

Non-equilibrium thermodynamics, maximum entropy production and Earth-system evolution

Kleidon

2010

Phil. Trans. R. Soc. A.

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The present-day atmosphere is in a unique state far from thermodynamic equilibrium. This uniqueness is for instance reflected in the high concentration of molecular oxygen and the low relative humidity in the atmosphere. Given that the concentration of atmospheric oxygen has likely increased throughout Earth-system history, we can ask whether this trend can be generalized to a trend of Earth-system evolution that is directed away from thermodynamic equilibrium, why we would expect such a trend to take place and what it would imply for Earth-system evolution as a whole. The justification for such a trend could be found in the proposed general principle of maximum entropy production (MEP), which states that non-equilibrium thermodynamic systems maintain steady states at which entropy production is maximized. Here, I justify and demonstrate this application of MEP to the Earth at the planetary scale. I first describe the non-equilibrium thermodynamic nature of Earth-system processes and distinguish processes that drive the system's state away from equilibrium from those that are directed towards equilibrium. I formulate the interactions among these processes from a thermodynamic perspective and then connect them to a holistic view of the planetary thermodynamic state of the Earth system. In conclusion, non-equilibrium thermodynamics and MEP have the potential to provide a simple and holistic theory of Earth-system functioning. This theory can be used to derive overall evolutionary trends of the Earth's past, identify the role that life plays in driving thermodynamic states far from equilibrium, identify habitability in other planetary environments and evaluate human impacts on Earth-system functioning.

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“…The accumulation of O 2 in the habitats of oxygenic photosynthetic organisms using Rubisco as their autotrophic carboxylase permits Rubisco oxygenase activity to occur, provided the CO 2 concentration is below saturation for Rubisco. Such decreased CO 2 concentrations, combined with at least local O 2 accumulation, probably occurred about 2 Ga, when there is evidence of an ice age extending to low palaeolatitudes [35,83].…”

Section: Oxygen Accumulation Rubisco Oxygenase and The Metabolism Ofmentioning

confidence: 99%

Algal evolution in relation to atmospheric CO ₂ : carboxylases, carbon-concentrating mechanisms and carbon oxidation cycles

Raven

Giordano

Beardall

et al. 2012

Phil. Trans. R. Soc. B

251

209

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Oxygenic photosynthesis evolved at least 2.4 Ga; all oxygenic organisms use the ribulose bisphosphate carboxylase-oxygenase (Rubisco) -photosynthetic carbon reduction cycle (PCRC) rather than one of the five other known pathways of autotrophic CO 2 assimilation. The high CO 2 and (initially) O 2 -free conditions permitted the use of a Rubisco with a high maximum specific reaction rate. As CO 2 decreased and O 2 increased, Rubisco oxygenase activity increased and 2-phosphoglycolate was produced, with the evolution of pathways recycling this inhibitory product to sugar phosphates. Changed atmospheric composition also selected for Rubiscos with higher CO 2 affinity and CO 2 /O 2 selectivity correlated with decreased CO 2 -saturated catalytic capacity and/or for CO 2 -concentrating mechanisms (CCMs). These changes increase the energy, nitrogen, phosphorus, iron, zinc and manganese cost of producing and operating Rubisco -PCRC, while biosphere oxygenation decreased the availability of nitrogen, phosphorus and iron. The majority of algae today have CCMs; the timing of their origins is unclear. If CCMs evolved in a low-CO 2 episode followed by one or more lengthy high-CO 2 episodes, CCM retention could involve a combination of environmental factors known to favour CCM retention in extant organisms that also occur in a warmer high-CO 2 ocean. More investigations, including studies of genetic adaptation, are needed.

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Low-latitude glaciation in the Palaeoproterozoic era

Cited by 311 publications

References 19 publications

Palaeoclimates: the first two billion years

Palaeoclimates: the first two billion years

Non-equilibrium thermodynamics, maximum entropy production and Earth-system evolution

Algal evolution in relation to atmospheric CO ₂ : carboxylases, carbon-concentrating mechanisms and carbon oxidation cycles

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Low-latitude glaciation in the Palaeoproterozoic era

Cited by 311 publications

References 19 publications

Palaeoclimates: the first two billion years

Palaeoclimates: the first two billion years

Non-equilibrium thermodynamics, maximum entropy production and Earth-system evolution

Algal evolution in relation to atmospheric CO 2 : carboxylases, carbon-concentrating mechanisms and carbon oxidation cycles

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Product

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Algal evolution in relation to atmospheric CO ₂ : carboxylases, carbon-concentrating mechanisms and carbon oxidation cycles