What led to the extinction of the Triassic dinosaurs? Cold, New Study Suggests

The three great geological eras dominated by dinosaurs were the Triassic, Jurassic and Cretaceous. They weren’t identical at all. These include differences of hundreds of millions of years, unique climates, different dominant organisms, and different extinctions. Recent research from the Columbia Climate School suggests an alternative ending to the story of the first dinosaurs to inhabit the planet when the supercontinent Pangea existed.

Not all dinosaurs went extinct for the same reason or at the same time. To determine the reasons for its disappearance, paleontologists argue between several hypotheses, according to the available data. For example, dinosaurs of the Cretaceous period, the period when species were most widespread, likely went extinct due to the impact of a 10-kilometer-diameter asteroid and its environmental consequences. Meanwhile, Triassic dinosaurs are believed to have gone extinct due to the effects of geological activity in their habitat.

A new study from Columbia University suggests that it was cold that wiped out the Triassic dinosaurs, giving way to all Jurassic species. Until recently, scientists believed that abnormal warming of the planet caused by volcanic activity caused by the natural separation of Pangea was to blame. This theory suggests that carbon dioxide released from the planet’s surface formed a kind of greenhouse effect unsuitable for life and acidified the oceans, wiping out most species.

Volcanic winter of the Triassic.

Scientists at the Lamont-Doherty Earth Observatory of the School of Climate Change have found evidence to the contrary. Instead of events occurring over hundreds of thousands of years, the lava eruptions would be sudden and abundant. Much of the sulfate emitted by these volcanoes would escape the planet’s atmosphere, and their reflective properties would impede the passage of light rays, concludes a study published in Proceedings of the National Academy of Sciences.

Geology refers to these cold events after constant eruptions such as volcanic winters. They work as follows: an erupting volcano releases sulfur dioxide. Sulfur dioxide combines with water vapor to form sulfuric acid and eventually turns into sulfate aerosols. These particles reflect and scatter solar radiation, limiting the light that naturally reaches the planet. Over the past 200 years, two similar events have occurred on the planet: the eruption of Mount Tambora in Indonesia in 1815 and the eruption of Mount Pinatubo in the Philippines in 1991.

The study took data from the Central Atlantic Igneous Province (CAMP), one of the largest igneous zones on the planet. Its formation 200 million years ago is associated with the breakup of Pangea and the opening of the Atlantic Ocean. In CAMP deposits in Morocco, Scotland and New Jersey, scientists found magnetic particles that revealed the frequency of lava pulses in the Late Triassic.

Many volcanoes across the vast continent have erupted in less than 100 years. The release of sulfates by the volcanic impulse was so great that the Sun was “almost blocked” and the drop in temperature was irreversible. Aerosols by their nature do not last long, so it is assumed that the volcanic winter did not last that long. However, scientists estimate that after the Triassic climate event, up to 50% of marine species and 25% of terrestrial species disappeared.