During the Great Oxidation Event, the rapid rise of atmospheric oxygen ( $O2\text{O}_2$ ) produced by early photosynthetic organisms drastically altered the Earth's climate system. Which of the following describes the primary geochemical mechanism by which this rise in $O2\text{O}_2$ triggered the Huronian glaciation (the 'Snowball Earth' epoch)?

$O2\text{O}_2$ reacted with atmospheric methane ( $CH4\text{CH}_4$ ), a highly potent greenhouse gas, converting it to carbon dioxide ( $CO2\text{CO}_2$ ) and water, which dramatically weakened the greenhouse effect.

$O2\text{O}_2$ accelerated the global rate of silicate weathering, which drew down vast amounts of nitrogen ( $N2\text{N}_2$ ) from the atmosphere and reduced atmospheric pressure and global temperatures.

The rise in $O2\text{O}_2$ accelerated the evolution and expansion of early terrestrial land plants, which directly sequestered water vapour from the atmosphere, leading to severe cooling.

$O2\text{O}_2$ precipitated dissolved oceanic iron to form banded iron formations, a highly exothermic reaction that disrupted atmospheric convection and caused runaway cloud formation.

The rise in $O2\text{O}_2$ accelerated the evolution and expansion of early terrestrial land plants, which directly sequestered water vapour from the atmosphere, leading to severe cooling.

$O2\text{O}_2$ precipitated dissolved oceanic iron to form banded iron formations, a highly exothermic reaction that disrupted atmospheric convection and caused runaway cloud formation.

Interpreting and interacting with earth systems

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Interpreting and interacting with earth systems

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Interpreting and interacting with earth systems

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Interpreting and interacting with earth systems Questions

Interpreting and interacting with earth systems

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Interpreting and interacting with earth systems Questions