Lessons from the past: The Triassic mass extinction

Paleogeographical location and the extent of CAMP are based on the work of Marzoli et al.

The end-Triassic mass extinction (ETME), one of the Phanerozoic’s largest mass extinctions, is typically attributed to climate change associated with degassing of basalt flows from the central Atlantic magmatic province (CAMP) emplaced during the initial rifting of Pangea. These massive volcanic eruptions released large quantities of carbon dioxide, sulphur dioxide, thermogenic methane, halocarbons, and heavy metals into the atmosphere, resulting in global warming, ocean acidification, and ozone layer depletion.

Most mammal-like reptiles and large amphibians disappeared, as well as early dinosaur groups. In the oceans, this event eliminated conodonts and nearly annihilated corals, ammonites, brachiopods, ostracods, radiolarians, and bivalves. The crisis amongst land plants at the end of the Triassic was severe with high occurrences of abnormal fern spores, indicating severe environmental stress.

A basaltic lava flow section from the Middle Atlas, Morocco. From Wikimedia Commons.

CAMP volcanism started about 100,000 years before the end-Triassic event (201.5 million years ago), with brief and intense eruptive pulses that released huge amounts of lava and greenhouse gases. A recent study estimated four short-lived (≤ 1000 years) volcanic pulses that triggered a cascade of catastrophic ecological and biological consequences. A single short-lived magmatic pulse of the first volcanic phase of CAMP would have released about 1.7 × 1017 mol CO2 in about 400 year. Moreover, the estimated degassing rate of each CAMP volcanic pulse is about 4.1 × 1014 mol/year CO2, the half of total amount of current anthropogenic emissions.

Human activity has significantly altered the climate in less than a century. Since 1970, global average temperatures have been rising at at 0.2°C per decade. Glaciers from the Greenland and Antarctic Ice Sheets are fading away, dumping 260 billion metric tons of water into the ocean every year. The ocean acidification is occurring at a rate faster than at any time in the last 300 million years, and the patterns of rainfall and drought are changing and undermining food security which have major implications for human health, welfare and social infrastructure. Other human societies have succumbed to climate change – like the Akkadians – while others have survived by changing their behavior in response to environmental change. If we want to stop the degradation of our planet, we need to act now.

References:

Capriolo, M., Mills, B. J., Newton, R. J., Dal Corso, J., Dunhill, A. M., Wignall, P. B., & Marzoli, A. (2022). Anthropogenic-scale CO2 degassing from the Central Atlantic Magmatic Province as a driver of the end-Triassic mass extinction. Global and Planetary Change, 103731 https://doi.org/10.1016/j.gloplacha.2021.103731

Lindström, S. (2021). Two-phased mass rarity and extinction in land plants during the end-Triassic climate crisis. Frontiers in Earth Science, 9, 1079 https://doi.org/10.3389/feart.2021.780343

He, Tianchen, et al. (2020). An enormous sulfur isotope excursion indicates marine anoxia during the end-Triassic mass extinction. Sci Adv. doi: 10.1126/sciadv.abb6704.

MARZOLI, Andrea, et al. (2018). The Central Atlantic magmatic province (CAMP): A review. The Late Triassic World, 91-125.