Dinosaur Death Theories: Did Carbon Dioxide from Volcanic Major Eruptions Killed Them?

Scientists have been studying the reasons for the demise of dinosaurs and assembled a timeline for the volcanic eruptions in India's Deccan Traps, EurekAlert! reported. Although many believe that an asteroid hitting Earth might have caused the extinction of dinosaurs, there are still other mass extinctions that coincide, like carbon dioxide outgassing from volcanic eruptions the role of volcanism in the dinosaurs' extinction.

In the past 500 million years, five mass extinctions already happened, and massive volcanic eruptions have been identified as the major driver that precipitated at least three of these extinctions. The most recent one happened 66 million years ago, the time when dinosaurs went extinct.

Researchers debated whether it was due to gas emissions from volcanic eruptions from the Deccan Traps or the impact of the large asteroid hitting Earth that has caused climate change and triggered the event.

But a recent study by a multinational research team led by The Graduate Center scientists analyzed the amount and timing of carbon dioxide outgassing to know what role volcanism played in climate change during the End-Cretaceous mass extinction, Mirage News reported.

The study, entitled "Reconciling early Deccan Traps CO2 outgassing and pre-KPB global climate," is published in the journal Proceedings of the National Academy of Sciences.

Deccan Traps Released Enough Carbon Dioxide To Cause Warming Event

Scientists have long debated whether the lavas that erupted have released enough carbon dioxide to cause warming.

Andres Hernandez Nava, a Ph.D. student in The Graduate Center, said that they analyzed the amount of outgassing of carbon dioxide from the lava volumes of Deccan Traps and found that it was not enough to cause global warming.

But when they included the outgassing of carbon dioxide from magmas that were frozen beneath the surface that did not erupt, they found that it could have released enough carbon dioxide to cause that level of global warming.

According to the news outlet, the team's data showed that the carbon dioxide outgassing from Deccan Traps magmas explains the global temperature warming that increased by almost 3 degrees Celsius during the early stage of Deccan volcanic activities.

But their data also showed that the warming lessened during the event of the mass extinction. That disfavors the theory that carbon dioxide was a major driver of the mass extinction 66 million years ago.

ALSO READ: New Theory of Dinosaur Extinction Involves Long-Distance Comet from Solar System's Edge

Measuring Amount of Carbon Dioxide

According to Phys.org, the team used lasers ad beams of ions to measure how much trapped carbon dioxide a tiny droplet of magma has. They also used the same method to measure other elements, including barium and niobium, that serve as proxies for how much carbon dioxide magmas have at the start.

Then they created a model of the climate of the Cretaceous at the time to determine the impacts of carbon dioxide releasing in Deccan Traps on surface temperatures. Their findings fill in the gap on how magmas interacted with the climate during the End-Cretaceous mass extinction.

"This work brings us closer to understanding the role of magmas in fundamentally shaping our planet's climate, and specifically helps us test the contributions of volcanism and the asteroid impact in the End-Cretaceous mass extinction," said Professor Black, the principal investigator of the study.