Paleocene-Eocene Thermal Maximum
c. 56 MYA · Prehistoric
Approximately 55.8 million years ago, a massive release of carbon raised global temperatures by 5 to 8 degrees Celsius over roughly 200,000 years. Ocean acidification dissolved carbonate shells of deep-sea benthic foraminifera, causing a severe deep-ocean extinction event. Simultaneously, mammalian species diversified and migrated across continents, with new orders appearing in North America and Europe. Atmospheric CO2 may have exceeded 2,000 parts per million during the peak warming interval.
Locations
North Atlantic Igneous Province
Topics
carbon cycleocean acidificationmammalian diversificationvolcanismgreenhouse climatepaleoclimatology
Connected Events — 5 Connections
PETM greenhouse conditions preceded the long cooling trend toward the Oligocene icehouse Oligocene Epoch begins
The Azolla bloom helped reverse the greenhouse conditions established during the PETM Arctic Azolla Bloom Draws Down Atmospheric CO2
Post-PETM cooling trends gradually shifted climate toward conditions favoring open grasslands Miocene Grassland Ecosystems Spread Across Continents
Post-extinction warming event following the K-Pg boundary Chicxulub Impact: Mass Extinction
The PETM 38 million years later repeated the pattern of volcanic CO₂ driving rapid global warming and ocean anoxia, though at smaller scale and shorter duration Oceanic Anoxic Event 2 Triggers the Cretaceous Thermal Maximum
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