‘Volcanic Winter’ Contributed to Earth’s Worst Mass Extinction 250 Million Years Ago: Study | The Weather Channel – Articles de The Weather Channel

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Minerals rich in copper indicating extensive volcanic activity at the end of the Permian mass extinction in different regions of southern China (A: locality of Taoshujing; B: locality of Lubei; C: Guanbachong; D: locality of Taoshujing; E: Longmendong locality). The minerals are all copper sulfides, mainly malachite – the green spots of the minerals.

(H. Zhang, Nanjing Institute of Geology and Paleontology)

Perhaps the most well-known extinction event is the fifth mass extinction event about 66 million years ago that destroyed the giant dinosaurs. But around 250 million years ago, the planet witnessed an even larger mass extinction event, possibly the largest in Earth’s history.

The geological period is known as the Permian, and the Late Permian extinction occurred around 250 million years ago. It was the largest in terms of impact in the timeline of over 500 million years when most familiar animal forms first evolved. The event killed nearly 90% of marine species as well as 75% of Earth’s then-terrestrial species.

But what drove this extinction event to be so powerful has always left scientists in awe. They have long speculated that there must be a combination of several forces that led to this global ecological catastrophe, including microbes, anaerobic conditions, climate change, and emissions of hydrogen sulfide.

And it turns out that an additional force had triggered this catastrophic event: the volcanic winter. The new idea comes from a study by New York University in which scientists analyzed minerals in southern China.

Diagram showing the formation process of copper-rich deposits in the EPME interval in southern China.  (NIGPAS)

Diagram showing the formation process of copper-rich deposits in the EPME interval in southern China.

(NIGPAS)

“Taking a closer look at the geological records around the time of the Great Extinction, we find that the late Permian global environmental catastrophe may have had multiple causes among marine and non-marine species,” says Michael Rampino, professor at the university’s biology department, in a statement from NYU.

Examination of these minerals from China (copper and mercury) helped scientists conclude that massive volcanic eruptions led to a volcanic winter during this period. The accumulation of volcanic ash and sulfur aerosols has led to a sharp drop in global temperatures.

The byproducts of massive volcanic eruptions can mask sunlight and increase Earth’s albedo or the ability to reflect solar radiation rather than absorb it. According to the official statement, this change was added to the environmental effects resulting from other phenomena 250 million years ago.

“Atmospheric sulfuric acid aerosols produced by the eruptions may have been the cause of a rapid global cooling of several degrees, before the severe warming observed throughout the Late Permian mass extinction interval.” , explains Michael Rampino, one of the co-authors of this study.

Previous scientists have projected several theories, the most plausible reason being extensive lava flooding through the Siberian traps. However, scientists were unable to understand how this triggered the extinction of so many species living both on land and at sea. This study advanced our understanding of how various extinction events shaped the life history of the planet.

The results of this study were published in the journal Scientists progress and can be accessed here.

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