Current CO2 levels are low compared to the last 590 million years
the verdict
SUPPORTED
the evidence backs this
confidence 92/100
Geological data and proxy reconstructions over the past several hundred million years show that Earth's atmospheric CO2 levels have frequently been much higher than they are today, making current concentrations relatively low in deep-time context.
Evidence for · 3
Atmospheric Carbon Dioxide Levels Over Phanerozoic Time
1990 · cited by 519
Geochemical modeling indicates that atmospheric CO2 levels were significantly higher during the early Paleozoic and Mesozoic, and are low during the late Cenozoic.
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More for · 2
A 485-million-year history of Earth’s surface temperature
2024 · cited by 196
Data assimilation reconstructions over the last 485 million years demonstrate that current CO2 levels are low compared to most of Earth's history.
A 300-million-year record of atmospheric carbon dioxide from fossil plant cuticles.
2001 · cited by 0
Stomatal proxy records from fossil plants confirm that CO2 concentrations were substantially higher across the Mesozoic than they are today.