Pangea on Acid: Extreme Environments, Climate, and Life during Permo-Triassic Time - Public Lecture

Ancient Warning Signs

The Permian-Triassic mass extinction, known as the Great Dying around 252 million years ago, eliminated over 80% of marine species and 70% of terrestrial vertebrates, driven primarily by massive volcanic eruptions in the Siberian Traps that released enormous volumes of CO₂ and sulfur compounds. These emissions caused rapid global warming of up to 10°C, ocean deoxygenation, and acidification, collapsing ecosystems worldwide.

Recent research from 2025 highlights why the aftermath proved so devastating: the collapse of tropical rainforests severely limited the planet's ability to draw down atmospheric carbon through vegetation and soils, turning a temporary spike into a multi-million-year hothouse. This vegetation loss amplified warming by reducing natural carbon sinks, with equatorial temperatures exceeding 34°C and polar regions shifting to temperate conditions.

Parallel concerns arise today as human emissions from fossil fuels drive similar changes—warming, acidification, and deoxygenation—at rates that some models suggest could accumulate to Permian-scale totals far faster than the ancient volcanic pulses. The stakes involve not just gradual shifts but potential crossing of tipping points where feedback loops, like reduced sequestration, entrench extreme conditions.

Non-obvious tensions include regional variations: equatorial and tropical zones suffered most severely due to lethal heat and acidified waters, while higher latitudes saw different recovery dynamics. Modern biodiversity loss, already exceeding the Great Dying's pace in some metrics, risks similar homogenization of marine communities as species track shifting habitable zones, with cascading effects on fisheries, coastal economies, and global food webs.

The event reshaped life on Earth, paving the way for dinosaurs and eventual mammalian dominance, but recovery took millions of years amid persistent instability—underscoring the long-term consequences of breaching climatic thresholds.